SemaDecl.cpp revision d6efafa5144a3e9942d1b09a246b118b1ba77a48
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 the 40/// declaration corresponding to that type. Otherwise, returns NULL. 41/// 42/// If name lookup results in an ambiguity, this routine will complain 43/// and then return NULL. 44Sema::DeclTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 45 Scope *S, const CXXScopeSpec *SS) { 46 Decl *IIDecl = 0; 47 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, false); 48 switch (Result.getKind()) { 49 case LookupResult::NotFound: 50 case LookupResult::FoundOverloaded: 51 return 0; 52 53 case LookupResult::AmbiguousBaseSubobjectTypes: 54 case LookupResult::AmbiguousBaseSubobjects: 55 case LookupResult::AmbiguousReference: 56 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 57 return 0; 58 59 case LookupResult::Found: 60 IIDecl = Result.getAsDecl(); 61 break; 62 } 63 64 if (IIDecl) { 65 if (isa<TypedefDecl>(IIDecl) || 66 isa<ObjCInterfaceDecl>(IIDecl) || 67 isa<TagDecl>(IIDecl) || 68 isa<TemplateTypeParmDecl>(IIDecl)) 69 return IIDecl; 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 } 608 } 609 } 610} 611 612/// MergeVarDecl - We just parsed a variable 'New' which has the same name 613/// and scope as a previous declaration 'Old'. Figure out how to resolve this 614/// situation, merging decls or emitting diagnostics as appropriate. 615/// 616/// Tentative definition rules (C99 6.9.2p2) are checked by 617/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 618/// definitions here, since the initializer hasn't been attached. 619/// 620VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 621 // Verify the old decl was also a variable. 622 VarDecl *Old = dyn_cast<VarDecl>(OldD); 623 if (!Old) { 624 Diag(New->getLocation(), diag::err_redefinition_different_kind) 625 << New->getDeclName(); 626 Diag(OldD->getLocation(), diag::note_previous_definition); 627 return New; 628 } 629 630 MergeAttributes(New, Old); 631 632 // Merge the types 633 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 634 if (MergedT.isNull()) { 635 Diag(New->getLocation(), diag::err_redefinition_different_type) 636 << New->getDeclName(); 637 Diag(Old->getLocation(), diag::note_previous_definition); 638 return New; 639 } 640 New->setType(MergedT); 641 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 642 if (New->getStorageClass() == VarDecl::Static && 643 (Old->getStorageClass() == VarDecl::None || 644 Old->getStorageClass() == VarDecl::Extern)) { 645 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 646 Diag(Old->getLocation(), diag::note_previous_definition); 647 return New; 648 } 649 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 650 if (New->getStorageClass() != VarDecl::Static && 651 Old->getStorageClass() == VarDecl::Static) { 652 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 653 Diag(Old->getLocation(), diag::note_previous_definition); 654 return New; 655 } 656 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 657 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 658 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 659 Diag(Old->getLocation(), diag::note_previous_definition); 660 } 661 return New; 662} 663 664/// CheckParmsForFunctionDef - Check that the parameters of the given 665/// function are appropriate for the definition of a function. This 666/// takes care of any checks that cannot be performed on the 667/// declaration itself, e.g., that the types of each of the function 668/// parameters are complete. 669bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 670 bool HasInvalidParm = false; 671 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 672 ParmVarDecl *Param = FD->getParamDecl(p); 673 674 // C99 6.7.5.3p4: the parameters in a parameter type list in a 675 // function declarator that is part of a function definition of 676 // that function shall not have incomplete type. 677 if (!Param->isInvalidDecl() && 678 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 679 diag::err_typecheck_decl_incomplete_type)) { 680 Param->setInvalidDecl(); 681 HasInvalidParm = true; 682 } 683 684 // C99 6.9.1p5: If the declarator includes a parameter type list, the 685 // declaration of each parameter shall include an identifier. 686 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 687 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 688 } 689 690 return HasInvalidParm; 691} 692 693/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 694/// no declarator (e.g. "struct foo;") is parsed. 695Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 696 TagDecl *Tag 697 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 698 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 699 if (!Record->getDeclName() && Record->isDefinition() && 700 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 701 return BuildAnonymousStructOrUnion(S, DS, Record); 702 703 // Microsoft allows unnamed struct/union fields. Don't complain 704 // about them. 705 // FIXME: Should we support Microsoft's extensions in this area? 706 if (Record->getDeclName() && getLangOptions().Microsoft) 707 return Tag; 708 } 709 710 if (!DS.isMissingDeclaratorOk()) { 711 // Warn about typedefs of enums without names, since this is an 712 // extension in both Microsoft an GNU. 713 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 714 Tag && isa<EnumDecl>(Tag)) { 715 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 716 << DS.getSourceRange(); 717 return Tag; 718 } 719 720 // FIXME: This diagnostic is emitted even when various previous 721 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 722 // DeclSpec has no means of communicating this information, and the 723 // responsible parser functions are quite far apart. 724 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 725 << DS.getSourceRange(); 726 return 0; 727 } 728 729 return Tag; 730} 731 732/// InjectAnonymousStructOrUnionMembers - Inject the members of the 733/// anonymous struct or union AnonRecord into the owning context Owner 734/// and scope S. This routine will be invoked just after we realize 735/// that an unnamed union or struct is actually an anonymous union or 736/// struct, e.g., 737/// 738/// @code 739/// union { 740/// int i; 741/// float f; 742/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 743/// // f into the surrounding scope.x 744/// @endcode 745/// 746/// This routine is recursive, injecting the names of nested anonymous 747/// structs/unions into the owning context and scope as well. 748bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 749 RecordDecl *AnonRecord) { 750 bool Invalid = false; 751 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 752 FEnd = AnonRecord->field_end(); 753 F != FEnd; ++F) { 754 if ((*F)->getDeclName()) { 755 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 756 LookupOrdinaryName, true); 757 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 758 // C++ [class.union]p2: 759 // The names of the members of an anonymous union shall be 760 // distinct from the names of any other entity in the 761 // scope in which the anonymous union is declared. 762 unsigned diagKind 763 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 764 : diag::err_anonymous_struct_member_redecl; 765 Diag((*F)->getLocation(), diagKind) 766 << (*F)->getDeclName(); 767 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 768 Invalid = true; 769 } else { 770 // C++ [class.union]p2: 771 // For the purpose of name lookup, after the anonymous union 772 // definition, the members of the anonymous union are 773 // considered to have been defined in the scope in which the 774 // anonymous union is declared. 775 Owner->makeDeclVisibleInContext(*F); 776 S->AddDecl(*F); 777 IdResolver.AddDecl(*F); 778 } 779 } else if (const RecordType *InnerRecordType 780 = (*F)->getType()->getAsRecordType()) { 781 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 782 if (InnerRecord->isAnonymousStructOrUnion()) 783 Invalid = Invalid || 784 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 785 } 786 } 787 788 return Invalid; 789} 790 791/// ActOnAnonymousStructOrUnion - Handle the declaration of an 792/// anonymous structure or union. Anonymous unions are a C++ feature 793/// (C++ [class.union]) and a GNU C extension; anonymous structures 794/// are a GNU C and GNU C++ extension. 795Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 796 RecordDecl *Record) { 797 DeclContext *Owner = Record->getDeclContext(); 798 799 // Diagnose whether this anonymous struct/union is an extension. 800 if (Record->isUnion() && !getLangOptions().CPlusPlus) 801 Diag(Record->getLocation(), diag::ext_anonymous_union); 802 else if (!Record->isUnion()) 803 Diag(Record->getLocation(), diag::ext_anonymous_struct); 804 805 // C and C++ require different kinds of checks for anonymous 806 // structs/unions. 807 bool Invalid = false; 808 if (getLangOptions().CPlusPlus) { 809 const char* PrevSpec = 0; 810 // C++ [class.union]p3: 811 // Anonymous unions declared in a named namespace or in the 812 // global namespace shall be declared static. 813 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 814 (isa<TranslationUnitDecl>(Owner) || 815 (isa<NamespaceDecl>(Owner) && 816 cast<NamespaceDecl>(Owner)->getDeclName()))) { 817 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 818 Invalid = true; 819 820 // Recover by adding 'static'. 821 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 822 } 823 // C++ [class.union]p3: 824 // A storage class is not allowed in a declaration of an 825 // anonymous union in a class scope. 826 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 827 isa<RecordDecl>(Owner)) { 828 Diag(DS.getStorageClassSpecLoc(), 829 diag::err_anonymous_union_with_storage_spec); 830 Invalid = true; 831 832 // Recover by removing the storage specifier. 833 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 834 PrevSpec); 835 } 836 837 // C++ [class.union]p2: 838 // The member-specification of an anonymous union shall only 839 // define non-static data members. [Note: nested types and 840 // functions cannot be declared within an anonymous union. ] 841 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 842 MemEnd = Record->decls_end(); 843 Mem != MemEnd; ++Mem) { 844 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 845 // C++ [class.union]p3: 846 // An anonymous union shall not have private or protected 847 // members (clause 11). 848 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 849 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 850 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 851 Invalid = true; 852 } 853 } else if ((*Mem)->isImplicit()) { 854 // Any implicit members are fine. 855 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 856 // This is a type that showed up in an 857 // elaborated-type-specifier inside the anonymous struct or 858 // union, but which actually declares a type outside of the 859 // anonymous struct or union. It's okay. 860 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 861 if (!MemRecord->isAnonymousStructOrUnion() && 862 MemRecord->getDeclName()) { 863 // This is a nested type declaration. 864 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 865 << (int)Record->isUnion(); 866 Invalid = true; 867 } 868 } else { 869 // We have something that isn't a non-static data 870 // member. Complain about it. 871 unsigned DK = diag::err_anonymous_record_bad_member; 872 if (isa<TypeDecl>(*Mem)) 873 DK = diag::err_anonymous_record_with_type; 874 else if (isa<FunctionDecl>(*Mem)) 875 DK = diag::err_anonymous_record_with_function; 876 else if (isa<VarDecl>(*Mem)) 877 DK = diag::err_anonymous_record_with_static; 878 Diag((*Mem)->getLocation(), DK) 879 << (int)Record->isUnion(); 880 Invalid = true; 881 } 882 } 883 } else { 884 // FIXME: Check GNU C semantics 885 if (Record->isUnion() && !Owner->isRecord()) { 886 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 887 << (int)getLangOptions().CPlusPlus; 888 Invalid = true; 889 } 890 } 891 892 if (!Record->isUnion() && !Owner->isRecord()) { 893 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 894 << (int)getLangOptions().CPlusPlus; 895 Invalid = true; 896 } 897 898 // Create a declaration for this anonymous struct/union. 899 NamedDecl *Anon = 0; 900 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 901 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 902 /*IdentifierInfo=*/0, 903 Context.getTypeDeclType(Record), 904 /*BitWidth=*/0, /*Mutable=*/false); 905 Anon->setAccess(AS_public); 906 if (getLangOptions().CPlusPlus) 907 FieldCollector->Add(cast<FieldDecl>(Anon)); 908 } else { 909 VarDecl::StorageClass SC; 910 switch (DS.getStorageClassSpec()) { 911 default: assert(0 && "Unknown storage class!"); 912 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 913 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 914 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 915 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 916 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 917 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 918 case DeclSpec::SCS_mutable: 919 // mutable can only appear on non-static class members, so it's always 920 // an error here 921 Diag(Record->getLocation(), diag::err_mutable_nonmember); 922 Invalid = true; 923 SC = VarDecl::None; 924 break; 925 } 926 927 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 928 /*IdentifierInfo=*/0, 929 Context.getTypeDeclType(Record), 930 SC, DS.getSourceRange().getBegin()); 931 } 932 Anon->setImplicit(); 933 934 // Add the anonymous struct/union object to the current 935 // context. We'll be referencing this object when we refer to one of 936 // its members. 937 Owner->addDecl(Anon); 938 939 // Inject the members of the anonymous struct/union into the owning 940 // context and into the identifier resolver chain for name lookup 941 // purposes. 942 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 943 Invalid = true; 944 945 // Mark this as an anonymous struct/union type. Note that we do not 946 // do this until after we have already checked and injected the 947 // members of this anonymous struct/union type, because otherwise 948 // the members could be injected twice: once by DeclContext when it 949 // builds its lookup table, and once by 950 // InjectAnonymousStructOrUnionMembers. 951 Record->setAnonymousStructOrUnion(true); 952 953 if (Invalid) 954 Anon->setInvalidDecl(); 955 956 return Anon; 957} 958 959bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 960 bool DirectInit) { 961 // Get the type before calling CheckSingleAssignmentConstraints(), since 962 // it can promote the expression. 963 QualType InitType = Init->getType(); 964 965 if (getLangOptions().CPlusPlus) { 966 // FIXME: I dislike this error message. A lot. 967 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 968 return Diag(Init->getSourceRange().getBegin(), 969 diag::err_typecheck_convert_incompatible) 970 << DeclType << Init->getType() << "initializing" 971 << Init->getSourceRange(); 972 973 return false; 974 } 975 976 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 977 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 978 InitType, Init, "initializing"); 979} 980 981bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 982 const ArrayType *AT = Context.getAsArrayType(DeclT); 983 984 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 985 // C99 6.7.8p14. We have an array of character type with unknown size 986 // being initialized to a string literal. 987 llvm::APSInt ConstVal(32); 988 ConstVal = strLiteral->getByteLength() + 1; 989 // Return a new array type (C99 6.7.8p22). 990 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 991 ArrayType::Normal, 0); 992 } else { 993 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 994 // C99 6.7.8p14. We have an array of character type with known size. 995 // FIXME: Avoid truncation for 64-bit length strings. 996 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 997 Diag(strLiteral->getSourceRange().getBegin(), 998 diag::warn_initializer_string_for_char_array_too_long) 999 << strLiteral->getSourceRange(); 1000 } 1001 // Set type from "char *" to "constant array of char". 1002 strLiteral->setType(DeclT); 1003 // For now, we always return false (meaning success). 1004 return false; 1005} 1006 1007StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1008 const ArrayType *AT = Context.getAsArrayType(DeclType); 1009 if (AT && AT->getElementType()->isCharType()) { 1010 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 1011 } 1012 return 0; 1013} 1014 1015bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1016 SourceLocation InitLoc, 1017 DeclarationName InitEntity, 1018 bool DirectInit) { 1019 if (DeclType->isDependentType() || Init->isTypeDependent()) 1020 return false; 1021 1022 // C++ [dcl.init.ref]p1: 1023 // A variable declared to be a T&, that is "reference to type T" 1024 // (8.3.2), shall be initialized by an object, or function, of 1025 // type T or by an object that can be converted into a T. 1026 if (DeclType->isReferenceType()) 1027 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1028 1029 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1030 // of unknown size ("[]") or an object type that is not a variable array type. 1031 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1032 return Diag(InitLoc, diag::err_variable_object_no_init) 1033 << VAT->getSizeExpr()->getSourceRange(); 1034 1035 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1036 if (!InitList) { 1037 // FIXME: Handle wide strings 1038 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1039 return CheckStringLiteralInit(strLiteral, DeclType); 1040 1041 // C++ [dcl.init]p14: 1042 // -- If the destination type is a (possibly cv-qualified) class 1043 // type: 1044 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1045 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1046 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1047 1048 // -- If the initialization is direct-initialization, or if it is 1049 // copy-initialization where the cv-unqualified version of the 1050 // source type is the same class as, or a derived class of, the 1051 // class of the destination, constructors are considered. 1052 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1053 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1054 CXXConstructorDecl *Constructor 1055 = PerformInitializationByConstructor(DeclType, &Init, 1, 1056 InitLoc, Init->getSourceRange(), 1057 InitEntity, 1058 DirectInit? IK_Direct : IK_Copy); 1059 return Constructor == 0; 1060 } 1061 1062 // -- Otherwise (i.e., for the remaining copy-initialization 1063 // cases), user-defined conversion sequences that can 1064 // convert from the source type to the destination type or 1065 // (when a conversion function is used) to a derived class 1066 // thereof are enumerated as described in 13.3.1.4, and the 1067 // best one is chosen through overload resolution 1068 // (13.3). If the conversion cannot be done or is 1069 // ambiguous, the initialization is ill-formed. The 1070 // function selected is called with the initializer 1071 // expression as its argument; if the function is a 1072 // constructor, the call initializes a temporary of the 1073 // destination type. 1074 // FIXME: We're pretending to do copy elision here; return to 1075 // this when we have ASTs for such things. 1076 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1077 return false; 1078 1079 if (InitEntity) 1080 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1081 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1082 << Init->getType() << Init->getSourceRange(); 1083 else 1084 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1085 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1086 << Init->getType() << Init->getSourceRange(); 1087 } 1088 1089 // C99 6.7.8p16. 1090 if (DeclType->isArrayType()) 1091 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1092 << Init->getSourceRange(); 1093 1094 return CheckSingleInitializer(Init, DeclType, DirectInit); 1095 } 1096 1097 bool hadError = CheckInitList(InitList, DeclType); 1098 Init = InitList; 1099 return hadError; 1100} 1101 1102/// GetNameForDeclarator - Determine the full declaration name for the 1103/// given Declarator. 1104DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1105 switch (D.getKind()) { 1106 case Declarator::DK_Abstract: 1107 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1108 return DeclarationName(); 1109 1110 case Declarator::DK_Normal: 1111 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1112 return DeclarationName(D.getIdentifier()); 1113 1114 case Declarator::DK_Constructor: { 1115 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1116 Ty = Context.getCanonicalType(Ty); 1117 return Context.DeclarationNames.getCXXConstructorName(Ty); 1118 } 1119 1120 case Declarator::DK_Destructor: { 1121 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1122 Ty = Context.getCanonicalType(Ty); 1123 return Context.DeclarationNames.getCXXDestructorName(Ty); 1124 } 1125 1126 case Declarator::DK_Conversion: { 1127 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1128 Ty = Context.getCanonicalType(Ty); 1129 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1130 } 1131 1132 case Declarator::DK_Operator: 1133 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1134 return Context.DeclarationNames.getCXXOperatorName( 1135 D.getOverloadedOperator()); 1136 } 1137 1138 assert(false && "Unknown name kind"); 1139 return DeclarationName(); 1140} 1141 1142/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1143/// functions Declaration and Definition are "nearly" matching. This 1144/// heuristic is used to improve diagnostics in the case where an 1145/// out-of-line member function definition doesn't match any 1146/// declaration within the class. 1147static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1148 FunctionDecl *Declaration, 1149 FunctionDecl *Definition) { 1150 if (Declaration->param_size() != Definition->param_size()) 1151 return false; 1152 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1153 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1154 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1155 1156 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1157 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1158 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1159 return false; 1160 } 1161 1162 return true; 1163} 1164 1165Sema::DeclTy * 1166Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1167 bool IsFunctionDefinition) { 1168 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1169 DeclarationName Name = GetNameForDeclarator(D); 1170 1171 // All of these full declarators require an identifier. If it doesn't have 1172 // one, the ParsedFreeStandingDeclSpec action should be used. 1173 if (!Name) { 1174 if (!D.getInvalidType()) // Reject this if we think it is valid. 1175 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1176 diag::err_declarator_need_ident) 1177 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1178 return 0; 1179 } 1180 1181 // The scope passed in may not be a decl scope. Zip up the scope tree until 1182 // we find one that is. 1183 while ((S->getFlags() & Scope::DeclScope) == 0 || 1184 (S->getFlags() & Scope::TemplateParamScope) != 0) 1185 S = S->getParent(); 1186 1187 DeclContext *DC; 1188 NamedDecl *PrevDecl; 1189 NamedDecl *New; 1190 bool InvalidDecl = false; 1191 1192 // See if this is a redefinition of a variable in the same scope. 1193 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1194 DC = CurContext; 1195 PrevDecl = LookupName(S, Name, LookupOrdinaryName); 1196 } else { // Something like "int foo::x;" 1197 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1198 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName); 1199 1200 // C++ 7.3.1.2p2: 1201 // Members (including explicit specializations of templates) of a named 1202 // namespace can also be defined outside that namespace by explicit 1203 // qualification of the name being defined, provided that the entity being 1204 // defined was already declared in the namespace and the definition appears 1205 // after the point of declaration in a namespace that encloses the 1206 // declarations namespace. 1207 // 1208 // Note that we only check the context at this point. We don't yet 1209 // have enough information to make sure that PrevDecl is actually 1210 // the declaration we want to match. For example, given: 1211 // 1212 // class X { 1213 // void f(); 1214 // void f(float); 1215 // }; 1216 // 1217 // void X::f(int) { } // ill-formed 1218 // 1219 // In this case, PrevDecl will point to the overload set 1220 // containing the two f's declared in X, but neither of them 1221 // matches. 1222 if (!CurContext->Encloses(DC)) { 1223 // The qualifying scope doesn't enclose the original declaration. 1224 // Emit diagnostic based on current scope. 1225 SourceLocation L = D.getIdentifierLoc(); 1226 SourceRange R = D.getCXXScopeSpec().getRange(); 1227 if (isa<FunctionDecl>(CurContext)) { 1228 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1229 } else { 1230 Diag(L, diag::err_invalid_declarator_scope) 1231 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1232 } 1233 InvalidDecl = true; 1234 } 1235 } 1236 1237 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1238 // Maybe we will complain about the shadowed template parameter. 1239 InvalidDecl = InvalidDecl 1240 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1241 // Just pretend that we didn't see the previous declaration. 1242 PrevDecl = 0; 1243 } 1244 1245 // In C++, the previous declaration we find might be a tag type 1246 // (class or enum). In this case, the new declaration will hide the 1247 // tag type. Note that this does does not apply if we're declaring a 1248 // typedef (C++ [dcl.typedef]p4). 1249 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1250 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1251 PrevDecl = 0; 1252 1253 QualType R = GetTypeForDeclarator(D, S); 1254 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1255 1256 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1257 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1258 InvalidDecl); 1259 } else if (R.getTypePtr()->isFunctionType()) { 1260 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1261 IsFunctionDefinition, InvalidDecl); 1262 } else { 1263 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1264 InvalidDecl); 1265 } 1266 1267 if (New == 0) 1268 return 0; 1269 1270 // Set the lexical context. If the declarator has a C++ scope specifier, the 1271 // lexical context will be different from the semantic context. 1272 New->setLexicalDeclContext(CurContext); 1273 1274 // If this has an identifier, add it to the scope stack. 1275 if (Name) 1276 PushOnScopeChains(New, S); 1277 // If any semantic error occurred, mark the decl as invalid. 1278 if (D.getInvalidType() || InvalidDecl) 1279 New->setInvalidDecl(); 1280 1281 return New; 1282} 1283 1284NamedDecl* 1285Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1286 QualType R, Decl* LastDeclarator, 1287 Decl* PrevDecl, bool& InvalidDecl) { 1288 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1289 if (D.getCXXScopeSpec().isSet()) { 1290 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1291 << D.getCXXScopeSpec().getRange(); 1292 InvalidDecl = true; 1293 // Pretend we didn't see the scope specifier. 1294 DC = 0; 1295 } 1296 1297 // Check that there are no default arguments (C++ only). 1298 if (getLangOptions().CPlusPlus) 1299 CheckExtraCXXDefaultArguments(D); 1300 1301 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1302 if (!NewTD) return 0; 1303 1304 // Handle attributes prior to checking for duplicates in MergeVarDecl 1305 ProcessDeclAttributes(NewTD, D); 1306 // Merge the decl with the existing one if appropriate. If the decl is 1307 // in an outer scope, it isn't the same thing. 1308 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1309 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1310 if (NewTD == 0) return 0; 1311 } 1312 1313 if (S->getFnParent() == 0) { 1314 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1315 // then it shall have block scope. 1316 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1317 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1318 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1319 else 1320 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1321 1322 InvalidDecl = true; 1323 } 1324 } 1325 return NewTD; 1326} 1327 1328NamedDecl* 1329Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1330 QualType R, Decl* LastDeclarator, 1331 Decl* PrevDecl, bool& InvalidDecl) { 1332 DeclarationName Name = GetNameForDeclarator(D); 1333 1334 // Check that there are no default arguments (C++ only). 1335 if (getLangOptions().CPlusPlus) 1336 CheckExtraCXXDefaultArguments(D); 1337 1338 if (R.getTypePtr()->isObjCInterfaceType()) { 1339 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1340 << D.getIdentifier(); 1341 InvalidDecl = true; 1342 } 1343 1344 VarDecl *NewVD; 1345 VarDecl::StorageClass SC; 1346 switch (D.getDeclSpec().getStorageClassSpec()) { 1347 default: assert(0 && "Unknown storage class!"); 1348 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1349 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1350 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1351 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1352 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1353 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1354 case DeclSpec::SCS_mutable: 1355 // mutable can only appear on non-static class members, so it's always 1356 // an error here 1357 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1358 InvalidDecl = true; 1359 SC = VarDecl::None; 1360 break; 1361 } 1362 1363 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1364 if (!II) { 1365 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1366 << Name.getAsString(); 1367 return 0; 1368 } 1369 1370 if (DC->isRecord()) { 1371 // This is a static data member for a C++ class. 1372 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1373 D.getIdentifierLoc(), II, 1374 R); 1375 } else { 1376 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1377 if (S->getFnParent() == 0) { 1378 // C99 6.9p2: The storage-class specifiers auto and register shall not 1379 // appear in the declaration specifiers in an external declaration. 1380 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1381 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1382 InvalidDecl = true; 1383 } 1384 } 1385 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1386 II, R, SC, 1387 // FIXME: Move to DeclGroup... 1388 D.getDeclSpec().getSourceRange().getBegin()); 1389 NewVD->setThreadSpecified(ThreadSpecified); 1390 } 1391 NewVD->setNextDeclarator(LastDeclarator); 1392 1393 // Handle attributes prior to checking for duplicates in MergeVarDecl 1394 ProcessDeclAttributes(NewVD, D); 1395 1396 // Handle GNU asm-label extension (encoded as an attribute). 1397 if (Expr *E = (Expr*) D.getAsmLabel()) { 1398 // The parser guarantees this is a string. 1399 StringLiteral *SE = cast<StringLiteral>(E); 1400 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1401 SE->getByteLength()))); 1402 } 1403 1404 // Emit an error if an address space was applied to decl with local storage. 1405 // This includes arrays of objects with address space qualifiers, but not 1406 // automatic variables that point to other address spaces. 1407 // ISO/IEC TR 18037 S5.1.2 1408 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1409 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1410 InvalidDecl = true; 1411 } 1412 // Merge the decl with the existing one if appropriate. If the decl is 1413 // in an outer scope, it isn't the same thing. 1414 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1415 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1416 // The user tried to define a non-static data member 1417 // out-of-line (C++ [dcl.meaning]p1). 1418 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1419 << D.getCXXScopeSpec().getRange(); 1420 NewVD->Destroy(Context); 1421 return 0; 1422 } 1423 1424 NewVD = MergeVarDecl(NewVD, PrevDecl); 1425 if (NewVD == 0) return 0; 1426 1427 if (D.getCXXScopeSpec().isSet()) { 1428 // No previous declaration in the qualifying scope. 1429 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1430 << Name << D.getCXXScopeSpec().getRange(); 1431 InvalidDecl = true; 1432 } 1433 } 1434 return NewVD; 1435} 1436 1437NamedDecl* 1438Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1439 QualType R, Decl *LastDeclarator, 1440 Decl* PrevDecl, bool IsFunctionDefinition, 1441 bool& InvalidDecl) { 1442 assert(R.getTypePtr()->isFunctionType()); 1443 1444 DeclarationName Name = GetNameForDeclarator(D); 1445 FunctionDecl::StorageClass SC = FunctionDecl::None; 1446 switch (D.getDeclSpec().getStorageClassSpec()) { 1447 default: assert(0 && "Unknown storage class!"); 1448 case DeclSpec::SCS_auto: 1449 case DeclSpec::SCS_register: 1450 case DeclSpec::SCS_mutable: 1451 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1452 InvalidDecl = true; 1453 break; 1454 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1455 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1456 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1457 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1458 } 1459 1460 bool isInline = D.getDeclSpec().isInlineSpecified(); 1461 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1462 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1463 1464 FunctionDecl *NewFD; 1465 if (D.getKind() == Declarator::DK_Constructor) { 1466 // This is a C++ constructor declaration. 1467 assert(DC->isRecord() && 1468 "Constructors can only be declared in a member context"); 1469 1470 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1471 1472 // Create the new declaration 1473 NewFD = CXXConstructorDecl::Create(Context, 1474 cast<CXXRecordDecl>(DC), 1475 D.getIdentifierLoc(), Name, R, 1476 isExplicit, isInline, 1477 /*isImplicitlyDeclared=*/false); 1478 1479 if (InvalidDecl) 1480 NewFD->setInvalidDecl(); 1481 } else if (D.getKind() == Declarator::DK_Destructor) { 1482 // This is a C++ destructor declaration. 1483 if (DC->isRecord()) { 1484 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1485 1486 NewFD = CXXDestructorDecl::Create(Context, 1487 cast<CXXRecordDecl>(DC), 1488 D.getIdentifierLoc(), Name, R, 1489 isInline, 1490 /*isImplicitlyDeclared=*/false); 1491 1492 if (InvalidDecl) 1493 NewFD->setInvalidDecl(); 1494 } else { 1495 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1496 1497 // Create a FunctionDecl to satisfy the function definition parsing 1498 // code path. 1499 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1500 Name, R, SC, isInline, 1501 // FIXME: Move to DeclGroup... 1502 D.getDeclSpec().getSourceRange().getBegin()); 1503 InvalidDecl = true; 1504 NewFD->setInvalidDecl(); 1505 } 1506 } else if (D.getKind() == Declarator::DK_Conversion) { 1507 if (!DC->isRecord()) { 1508 Diag(D.getIdentifierLoc(), 1509 diag::err_conv_function_not_member); 1510 return 0; 1511 } else { 1512 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1513 1514 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1515 D.getIdentifierLoc(), Name, R, 1516 isInline, isExplicit); 1517 1518 if (InvalidDecl) 1519 NewFD->setInvalidDecl(); 1520 } 1521 } else if (DC->isRecord()) { 1522 // This is a C++ method declaration. 1523 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1524 D.getIdentifierLoc(), Name, R, 1525 (SC == FunctionDecl::Static), isInline); 1526 } else { 1527 NewFD = FunctionDecl::Create(Context, DC, 1528 D.getIdentifierLoc(), 1529 Name, R, SC, isInline, 1530 // FIXME: Move to DeclGroup... 1531 D.getDeclSpec().getSourceRange().getBegin()); 1532 } 1533 NewFD->setNextDeclarator(LastDeclarator); 1534 1535 // Set the lexical context. If the declarator has a C++ 1536 // scope specifier, the lexical context will be different 1537 // from the semantic context. 1538 NewFD->setLexicalDeclContext(CurContext); 1539 1540 // Handle GNU asm-label extension (encoded as an attribute). 1541 if (Expr *E = (Expr*) D.getAsmLabel()) { 1542 // The parser guarantees this is a string. 1543 StringLiteral *SE = cast<StringLiteral>(E); 1544 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1545 SE->getByteLength()))); 1546 } 1547 1548 // Copy the parameter declarations from the declarator D to 1549 // the function declaration NewFD, if they are available. 1550 if (D.getNumTypeObjects() > 0) { 1551 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1552 1553 // Create Decl objects for each parameter, adding them to the 1554 // FunctionDecl. 1555 llvm::SmallVector<ParmVarDecl*, 16> Params; 1556 1557 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1558 // function that takes no arguments, not a function that takes a 1559 // single void argument. 1560 // We let through "const void" here because Sema::GetTypeForDeclarator 1561 // already checks for that case. 1562 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1563 FTI.ArgInfo[0].Param && 1564 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1565 // empty arg list, don't push any params. 1566 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1567 1568 // In C++, the empty parameter-type-list must be spelled "void"; a 1569 // typedef of void is not permitted. 1570 if (getLangOptions().CPlusPlus && 1571 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1572 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1573 } 1574 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1575 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1576 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1577 } 1578 1579 NewFD->setParams(Context, &Params[0], Params.size()); 1580 } else if (R->getAsTypedefType()) { 1581 // When we're declaring a function with a typedef, as in the 1582 // following example, we'll need to synthesize (unnamed) 1583 // parameters for use in the declaration. 1584 // 1585 // @code 1586 // typedef void fn(int); 1587 // fn f; 1588 // @endcode 1589 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1590 if (!FT) { 1591 // This is a typedef of a function with no prototype, so we 1592 // don't need to do anything. 1593 } else if ((FT->getNumArgs() == 0) || 1594 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1595 FT->getArgType(0)->isVoidType())) { 1596 // This is a zero-argument function. We don't need to do anything. 1597 } else { 1598 // Synthesize a parameter for each argument type. 1599 llvm::SmallVector<ParmVarDecl*, 16> Params; 1600 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1601 ArgType != FT->arg_type_end(); ++ArgType) { 1602 Params.push_back(ParmVarDecl::Create(Context, DC, 1603 SourceLocation(), 0, 1604 *ArgType, VarDecl::None, 1605 0)); 1606 } 1607 1608 NewFD->setParams(Context, &Params[0], Params.size()); 1609 } 1610 } 1611 1612 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1613 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1614 else if (isa<CXXDestructorDecl>(NewFD)) { 1615 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1616 Record->setUserDeclaredDestructor(true); 1617 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1618 // user-defined destructor. 1619 Record->setPOD(false); 1620 } else if (CXXConversionDecl *Conversion = 1621 dyn_cast<CXXConversionDecl>(NewFD)) 1622 ActOnConversionDeclarator(Conversion); 1623 1624 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1625 if (NewFD->isOverloadedOperator() && 1626 CheckOverloadedOperatorDeclaration(NewFD)) 1627 NewFD->setInvalidDecl(); 1628 1629 // Merge the decl with the existing one if appropriate. Since C functions 1630 // are in a flat namespace, make sure we consider decls in outer scopes. 1631 if (PrevDecl && 1632 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1633 bool Redeclaration = false; 1634 1635 // If C++, determine whether NewFD is an overload of PrevDecl or 1636 // a declaration that requires merging. If it's an overload, 1637 // there's no more work to do here; we'll just add the new 1638 // function to the scope. 1639 OverloadedFunctionDecl::function_iterator MatchedDecl; 1640 if (!getLangOptions().CPlusPlus || 1641 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1642 Decl *OldDecl = PrevDecl; 1643 1644 // If PrevDecl was an overloaded function, extract the 1645 // FunctionDecl that matched. 1646 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1647 OldDecl = *MatchedDecl; 1648 1649 // NewFD and PrevDecl represent declarations that need to be 1650 // merged. 1651 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1652 1653 if (NewFD == 0) return 0; 1654 if (Redeclaration) { 1655 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1656 1657 // An out-of-line member function declaration must also be a 1658 // definition (C++ [dcl.meaning]p1). 1659 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1660 !InvalidDecl) { 1661 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1662 << D.getCXXScopeSpec().getRange(); 1663 NewFD->setInvalidDecl(); 1664 } 1665 } 1666 } 1667 1668 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1669 // The user tried to provide an out-of-line definition for a 1670 // member function, but there was no such member function 1671 // declared (C++ [class.mfct]p2). For example: 1672 // 1673 // class X { 1674 // void f() const; 1675 // }; 1676 // 1677 // void X::f() { } // ill-formed 1678 // 1679 // Complain about this problem, and attempt to suggest close 1680 // matches (e.g., those that differ only in cv-qualifiers and 1681 // whether the parameter types are references). 1682 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1683 << cast<CXXRecordDecl>(DC)->getDeclName() 1684 << D.getCXXScopeSpec().getRange(); 1685 InvalidDecl = true; 1686 1687 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1688 true); 1689 assert(!Prev.isAmbiguous() && 1690 "Cannot have an ambiguity in previous-declaration lookup"); 1691 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1692 Func != FuncEnd; ++Func) { 1693 if (isa<CXXMethodDecl>(*Func) && 1694 isNearlyMatchingMemberFunction(Context, cast<FunctionDecl>(*Func), 1695 NewFD)) 1696 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1697 } 1698 1699 PrevDecl = 0; 1700 } 1701 } 1702 1703 // Handle attributes. We need to have merged decls when handling attributes 1704 // (for example to check for conflicts, etc). 1705 ProcessDeclAttributes(NewFD, D); 1706 1707 if (getLangOptions().CPlusPlus) { 1708 // In C++, check default arguments now that we have merged decls. 1709 CheckCXXDefaultArguments(NewFD); 1710 1711 // An out-of-line member function declaration must also be a 1712 // definition (C++ [dcl.meaning]p1). 1713 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1714 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1715 << D.getCXXScopeSpec().getRange(); 1716 InvalidDecl = true; 1717 } 1718 } 1719 return NewFD; 1720} 1721 1722void Sema::InitializerElementNotConstant(const Expr *Init) { 1723 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1724 << Init->getSourceRange(); 1725} 1726 1727bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1728 switch (Init->getStmtClass()) { 1729 default: 1730 InitializerElementNotConstant(Init); 1731 return true; 1732 case Expr::ParenExprClass: { 1733 const ParenExpr* PE = cast<ParenExpr>(Init); 1734 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1735 } 1736 case Expr::CompoundLiteralExprClass: 1737 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1738 case Expr::DeclRefExprClass: 1739 case Expr::QualifiedDeclRefExprClass: { 1740 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1741 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1742 if (VD->hasGlobalStorage()) 1743 return false; 1744 InitializerElementNotConstant(Init); 1745 return true; 1746 } 1747 if (isa<FunctionDecl>(D)) 1748 return false; 1749 InitializerElementNotConstant(Init); 1750 return true; 1751 } 1752 case Expr::MemberExprClass: { 1753 const MemberExpr *M = cast<MemberExpr>(Init); 1754 if (M->isArrow()) 1755 return CheckAddressConstantExpression(M->getBase()); 1756 return CheckAddressConstantExpressionLValue(M->getBase()); 1757 } 1758 case Expr::ArraySubscriptExprClass: { 1759 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1760 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1761 return CheckAddressConstantExpression(ASE->getBase()) || 1762 CheckArithmeticConstantExpression(ASE->getIdx()); 1763 } 1764 case Expr::StringLiteralClass: 1765 case Expr::PredefinedExprClass: 1766 return false; 1767 case Expr::UnaryOperatorClass: { 1768 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1769 1770 // C99 6.6p9 1771 if (Exp->getOpcode() == UnaryOperator::Deref) 1772 return CheckAddressConstantExpression(Exp->getSubExpr()); 1773 1774 InitializerElementNotConstant(Init); 1775 return true; 1776 } 1777 } 1778} 1779 1780bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1781 switch (Init->getStmtClass()) { 1782 default: 1783 InitializerElementNotConstant(Init); 1784 return true; 1785 case Expr::ParenExprClass: 1786 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1787 case Expr::StringLiteralClass: 1788 case Expr::ObjCStringLiteralClass: 1789 return false; 1790 case Expr::CallExprClass: 1791 case Expr::CXXOperatorCallExprClass: 1792 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1793 if (cast<CallExpr>(Init)->isBuiltinCall() == 1794 Builtin::BI__builtin___CFStringMakeConstantString) 1795 return false; 1796 1797 InitializerElementNotConstant(Init); 1798 return true; 1799 1800 case Expr::UnaryOperatorClass: { 1801 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1802 1803 // C99 6.6p9 1804 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1805 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1806 1807 if (Exp->getOpcode() == UnaryOperator::Extension) 1808 return CheckAddressConstantExpression(Exp->getSubExpr()); 1809 1810 InitializerElementNotConstant(Init); 1811 return true; 1812 } 1813 case Expr::BinaryOperatorClass: { 1814 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1815 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1816 1817 Expr *PExp = Exp->getLHS(); 1818 Expr *IExp = Exp->getRHS(); 1819 if (IExp->getType()->isPointerType()) 1820 std::swap(PExp, IExp); 1821 1822 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1823 return CheckAddressConstantExpression(PExp) || 1824 CheckArithmeticConstantExpression(IExp); 1825 } 1826 case Expr::ImplicitCastExprClass: 1827 case Expr::CStyleCastExprClass: { 1828 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1829 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1830 // Check for implicit promotion 1831 if (SubExpr->getType()->isFunctionType() || 1832 SubExpr->getType()->isArrayType()) 1833 return CheckAddressConstantExpressionLValue(SubExpr); 1834 } 1835 1836 // Check for pointer->pointer cast 1837 if (SubExpr->getType()->isPointerType()) 1838 return CheckAddressConstantExpression(SubExpr); 1839 1840 if (SubExpr->getType()->isIntegralType()) { 1841 // Check for the special-case of a pointer->int->pointer cast; 1842 // this isn't standard, but some code requires it. See 1843 // PR2720 for an example. 1844 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1845 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1846 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1847 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1848 if (IntWidth >= PointerWidth) { 1849 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1850 } 1851 } 1852 } 1853 } 1854 if (SubExpr->getType()->isArithmeticType()) { 1855 return CheckArithmeticConstantExpression(SubExpr); 1856 } 1857 1858 InitializerElementNotConstant(Init); 1859 return true; 1860 } 1861 case Expr::ConditionalOperatorClass: { 1862 // FIXME: Should we pedwarn here? 1863 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1864 if (!Exp->getCond()->getType()->isArithmeticType()) { 1865 InitializerElementNotConstant(Init); 1866 return true; 1867 } 1868 if (CheckArithmeticConstantExpression(Exp->getCond())) 1869 return true; 1870 if (Exp->getLHS() && 1871 CheckAddressConstantExpression(Exp->getLHS())) 1872 return true; 1873 return CheckAddressConstantExpression(Exp->getRHS()); 1874 } 1875 case Expr::AddrLabelExprClass: 1876 return false; 1877 } 1878} 1879 1880static const Expr* FindExpressionBaseAddress(const Expr* E); 1881 1882static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1883 switch (E->getStmtClass()) { 1884 default: 1885 return E; 1886 case Expr::ParenExprClass: { 1887 const ParenExpr* PE = cast<ParenExpr>(E); 1888 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1889 } 1890 case Expr::MemberExprClass: { 1891 const MemberExpr *M = cast<MemberExpr>(E); 1892 if (M->isArrow()) 1893 return FindExpressionBaseAddress(M->getBase()); 1894 return FindExpressionBaseAddressLValue(M->getBase()); 1895 } 1896 case Expr::ArraySubscriptExprClass: { 1897 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1898 return FindExpressionBaseAddress(ASE->getBase()); 1899 } 1900 case Expr::UnaryOperatorClass: { 1901 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1902 1903 if (Exp->getOpcode() == UnaryOperator::Deref) 1904 return FindExpressionBaseAddress(Exp->getSubExpr()); 1905 1906 return E; 1907 } 1908 } 1909} 1910 1911static const Expr* FindExpressionBaseAddress(const Expr* E) { 1912 switch (E->getStmtClass()) { 1913 default: 1914 return E; 1915 case Expr::ParenExprClass: { 1916 const ParenExpr* PE = cast<ParenExpr>(E); 1917 return FindExpressionBaseAddress(PE->getSubExpr()); 1918 } 1919 case Expr::UnaryOperatorClass: { 1920 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1921 1922 // C99 6.6p9 1923 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1924 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1925 1926 if (Exp->getOpcode() == UnaryOperator::Extension) 1927 return FindExpressionBaseAddress(Exp->getSubExpr()); 1928 1929 return E; 1930 } 1931 case Expr::BinaryOperatorClass: { 1932 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1933 1934 Expr *PExp = Exp->getLHS(); 1935 Expr *IExp = Exp->getRHS(); 1936 if (IExp->getType()->isPointerType()) 1937 std::swap(PExp, IExp); 1938 1939 return FindExpressionBaseAddress(PExp); 1940 } 1941 case Expr::ImplicitCastExprClass: { 1942 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1943 1944 // Check for implicit promotion 1945 if (SubExpr->getType()->isFunctionType() || 1946 SubExpr->getType()->isArrayType()) 1947 return FindExpressionBaseAddressLValue(SubExpr); 1948 1949 // Check for pointer->pointer cast 1950 if (SubExpr->getType()->isPointerType()) 1951 return FindExpressionBaseAddress(SubExpr); 1952 1953 // We assume that we have an arithmetic expression here; 1954 // if we don't, we'll figure it out later 1955 return 0; 1956 } 1957 case Expr::CStyleCastExprClass: { 1958 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 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 } 1969} 1970 1971bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1972 switch (Init->getStmtClass()) { 1973 default: 1974 InitializerElementNotConstant(Init); 1975 return true; 1976 case Expr::ParenExprClass: { 1977 const ParenExpr* PE = cast<ParenExpr>(Init); 1978 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1979 } 1980 case Expr::FloatingLiteralClass: 1981 case Expr::IntegerLiteralClass: 1982 case Expr::CharacterLiteralClass: 1983 case Expr::ImaginaryLiteralClass: 1984 case Expr::TypesCompatibleExprClass: 1985 case Expr::CXXBoolLiteralExprClass: 1986 return false; 1987 case Expr::CallExprClass: 1988 case Expr::CXXOperatorCallExprClass: { 1989 const CallExpr *CE = cast<CallExpr>(Init); 1990 1991 // Allow any constant foldable calls to builtins. 1992 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 1993 return false; 1994 1995 InitializerElementNotConstant(Init); 1996 return true; 1997 } 1998 case Expr::DeclRefExprClass: 1999 case Expr::QualifiedDeclRefExprClass: { 2000 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2001 if (isa<EnumConstantDecl>(D)) 2002 return false; 2003 InitializerElementNotConstant(Init); 2004 return true; 2005 } 2006 case Expr::CompoundLiteralExprClass: 2007 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2008 // but vectors are allowed to be magic. 2009 if (Init->getType()->isVectorType()) 2010 return false; 2011 InitializerElementNotConstant(Init); 2012 return true; 2013 case Expr::UnaryOperatorClass: { 2014 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2015 2016 switch (Exp->getOpcode()) { 2017 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2018 // See C99 6.6p3. 2019 default: 2020 InitializerElementNotConstant(Init); 2021 return true; 2022 case UnaryOperator::OffsetOf: 2023 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2024 return false; 2025 InitializerElementNotConstant(Init); 2026 return true; 2027 case UnaryOperator::Extension: 2028 case UnaryOperator::LNot: 2029 case UnaryOperator::Plus: 2030 case UnaryOperator::Minus: 2031 case UnaryOperator::Not: 2032 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2033 } 2034 } 2035 case Expr::SizeOfAlignOfExprClass: { 2036 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2037 // Special check for void types, which are allowed as an extension 2038 if (Exp->getTypeOfArgument()->isVoidType()) 2039 return false; 2040 // alignof always evaluates to a constant. 2041 // FIXME: is sizeof(int[3.0]) a constant expression? 2042 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2043 InitializerElementNotConstant(Init); 2044 return true; 2045 } 2046 return false; 2047 } 2048 case Expr::BinaryOperatorClass: { 2049 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2050 2051 if (Exp->getLHS()->getType()->isArithmeticType() && 2052 Exp->getRHS()->getType()->isArithmeticType()) { 2053 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2054 CheckArithmeticConstantExpression(Exp->getRHS()); 2055 } 2056 2057 if (Exp->getLHS()->getType()->isPointerType() && 2058 Exp->getRHS()->getType()->isPointerType()) { 2059 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2060 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2061 2062 // Only allow a null (constant integer) base; we could 2063 // allow some additional cases if necessary, but this 2064 // is sufficient to cover offsetof-like constructs. 2065 if (!LHSBase && !RHSBase) { 2066 return CheckAddressConstantExpression(Exp->getLHS()) || 2067 CheckAddressConstantExpression(Exp->getRHS()); 2068 } 2069 } 2070 2071 InitializerElementNotConstant(Init); 2072 return true; 2073 } 2074 case Expr::ImplicitCastExprClass: 2075 case Expr::CStyleCastExprClass: { 2076 const CastExpr *CE = cast<CastExpr>(Init); 2077 const Expr *SubExpr = CE->getSubExpr(); 2078 2079 if (SubExpr->getType()->isArithmeticType()) 2080 return CheckArithmeticConstantExpression(SubExpr); 2081 2082 if (SubExpr->getType()->isPointerType()) { 2083 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2084 if (Base) { 2085 // the cast is only valid if done to a wide enough type 2086 if (Context.getTypeSize(CE->getType()) >= 2087 Context.getTypeSize(SubExpr->getType())) 2088 return false; 2089 } else { 2090 // If the pointer has a null base, this is an offsetof-like construct 2091 return CheckAddressConstantExpression(SubExpr); 2092 } 2093 } 2094 2095 InitializerElementNotConstant(Init); 2096 return true; 2097 } 2098 case Expr::ConditionalOperatorClass: { 2099 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2100 2101 // If GNU extensions are disabled, we require all operands to be arithmetic 2102 // constant expressions. 2103 if (getLangOptions().NoExtensions) { 2104 return CheckArithmeticConstantExpression(Exp->getCond()) || 2105 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2106 CheckArithmeticConstantExpression(Exp->getRHS()); 2107 } 2108 2109 // Otherwise, we have to emulate some of the behavior of fold here. 2110 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2111 // because it can constant fold things away. To retain compatibility with 2112 // GCC code, we see if we can fold the condition to a constant (which we 2113 // should always be able to do in theory). If so, we only require the 2114 // specified arm of the conditional to be a constant. This is a horrible 2115 // hack, but is require by real world code that uses __builtin_constant_p. 2116 Expr::EvalResult EvalResult; 2117 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2118 EvalResult.HasSideEffects) { 2119 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2120 // won't be able to either. Use it to emit the diagnostic though. 2121 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2122 assert(Res && "Evaluate couldn't evaluate this constant?"); 2123 return Res; 2124 } 2125 2126 // Verify that the side following the condition is also a constant. 2127 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2128 if (EvalResult.Val.getInt() == 0) 2129 std::swap(TrueSide, FalseSide); 2130 2131 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2132 return true; 2133 2134 // Okay, the evaluated side evaluates to a constant, so we accept this. 2135 // Check to see if the other side is obviously not a constant. If so, 2136 // emit a warning that this is a GNU extension. 2137 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2138 Diag(Init->getExprLoc(), 2139 diag::ext_typecheck_expression_not_constant_but_accepted) 2140 << FalseSide->getSourceRange(); 2141 return false; 2142 } 2143 } 2144} 2145 2146bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2147 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2148 Init = DIE->getInit(); 2149 2150 Init = Init->IgnoreParens(); 2151 2152 if (Init->isEvaluatable(Context)) 2153 return false; 2154 2155 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2156 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2157 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2158 2159 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2160 return CheckForConstantInitializer(e->getInitializer(), DclT); 2161 2162 if (isa<ImplicitValueInitExpr>(Init)) { 2163 // FIXME: In C++, check for non-POD types. 2164 return false; 2165 } 2166 2167 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2168 unsigned numInits = Exp->getNumInits(); 2169 for (unsigned i = 0; i < numInits; i++) { 2170 // FIXME: Need to get the type of the declaration for C++, 2171 // because it could be a reference? 2172 2173 if (CheckForConstantInitializer(Exp->getInit(i), 2174 Exp->getInit(i)->getType())) 2175 return true; 2176 } 2177 return false; 2178 } 2179 2180 // FIXME: We can probably remove some of this code below, now that 2181 // Expr::Evaluate is doing the heavy lifting for scalars. 2182 2183 if (Init->isNullPointerConstant(Context)) 2184 return false; 2185 if (Init->getType()->isArithmeticType()) { 2186 QualType InitTy = Context.getCanonicalType(Init->getType()) 2187 .getUnqualifiedType(); 2188 if (InitTy == Context.BoolTy) { 2189 // Special handling for pointers implicitly cast to bool; 2190 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2191 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2192 Expr* SubE = ICE->getSubExpr(); 2193 if (SubE->getType()->isPointerType() || 2194 SubE->getType()->isArrayType() || 2195 SubE->getType()->isFunctionType()) { 2196 return CheckAddressConstantExpression(Init); 2197 } 2198 } 2199 } else if (InitTy->isIntegralType()) { 2200 Expr* SubE = 0; 2201 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2202 SubE = CE->getSubExpr(); 2203 // Special check for pointer cast to int; we allow as an extension 2204 // an address constant cast to an integer if the integer 2205 // is of an appropriate width (this sort of code is apparently used 2206 // in some places). 2207 // FIXME: Add pedwarn? 2208 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2209 if (SubE && (SubE->getType()->isPointerType() || 2210 SubE->getType()->isArrayType() || 2211 SubE->getType()->isFunctionType())) { 2212 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2213 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2214 if (IntWidth >= PointerWidth) 2215 return CheckAddressConstantExpression(Init); 2216 } 2217 } 2218 2219 return CheckArithmeticConstantExpression(Init); 2220 } 2221 2222 if (Init->getType()->isPointerType()) 2223 return CheckAddressConstantExpression(Init); 2224 2225 // An array type at the top level that isn't an init-list must 2226 // be a string literal 2227 if (Init->getType()->isArrayType()) 2228 return false; 2229 2230 if (Init->getType()->isFunctionType()) 2231 return false; 2232 2233 // Allow block exprs at top level. 2234 if (Init->getType()->isBlockPointerType()) 2235 return false; 2236 2237 // GCC cast to union extension 2238 // note: the validity of the cast expr is checked by CheckCastTypes() 2239 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2240 QualType T = C->getType(); 2241 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2242 } 2243 2244 InitializerElementNotConstant(Init); 2245 return true; 2246} 2247 2248void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2249 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2250} 2251 2252/// AddInitializerToDecl - Adds the initializer Init to the 2253/// declaration dcl. If DirectInit is true, this is C++ direct 2254/// initialization rather than copy initialization. 2255void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2256 Decl *RealDecl = static_cast<Decl *>(dcl); 2257 Expr *Init = static_cast<Expr *>(init.release()); 2258 assert(Init && "missing initializer"); 2259 2260 // If there is no declaration, there was an error parsing it. Just ignore 2261 // the initializer. 2262 if (RealDecl == 0) { 2263 delete Init; 2264 return; 2265 } 2266 2267 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2268 if (!VDecl) { 2269 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2270 RealDecl->setInvalidDecl(); 2271 return; 2272 } 2273 // Get the decls type and save a reference for later, since 2274 // CheckInitializerTypes may change it. 2275 QualType DclT = VDecl->getType(), SavT = DclT; 2276 if (VDecl->isBlockVarDecl()) { 2277 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2278 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2279 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2280 VDecl->setInvalidDecl(); 2281 } else if (!VDecl->isInvalidDecl()) { 2282 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2283 VDecl->getDeclName(), DirectInit)) 2284 VDecl->setInvalidDecl(); 2285 2286 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2287 if (!getLangOptions().CPlusPlus) { 2288 if (SC == VarDecl::Static) // C99 6.7.8p4. 2289 CheckForConstantInitializer(Init, DclT); 2290 } 2291 } 2292 } else if (VDecl->isFileVarDecl()) { 2293 if (VDecl->getStorageClass() == VarDecl::Extern) 2294 Diag(VDecl->getLocation(), diag::warn_extern_init); 2295 if (!VDecl->isInvalidDecl()) 2296 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2297 VDecl->getDeclName(), DirectInit)) 2298 VDecl->setInvalidDecl(); 2299 2300 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2301 if (!getLangOptions().CPlusPlus) { 2302 // C99 6.7.8p4. All file scoped initializers need to be constant. 2303 CheckForConstantInitializer(Init, DclT); 2304 } 2305 } 2306 // If the type changed, it means we had an incomplete type that was 2307 // completed by the initializer. For example: 2308 // int ary[] = { 1, 3, 5 }; 2309 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2310 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2311 VDecl->setType(DclT); 2312 Init->setType(DclT); 2313 } 2314 2315 // Attach the initializer to the decl. 2316 VDecl->setInit(Init); 2317 return; 2318} 2319 2320void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2321 Decl *RealDecl = static_cast<Decl *>(dcl); 2322 2323 // If there is no declaration, there was an error parsing it. Just ignore it. 2324 if (RealDecl == 0) 2325 return; 2326 2327 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2328 QualType Type = Var->getType(); 2329 // C++ [dcl.init.ref]p3: 2330 // The initializer can be omitted for a reference only in a 2331 // parameter declaration (8.3.5), in the declaration of a 2332 // function return type, in the declaration of a class member 2333 // within its class declaration (9.2), and where the extern 2334 // specifier is explicitly used. 2335 if (Type->isReferenceType() && 2336 Var->getStorageClass() != VarDecl::Extern && 2337 Var->getStorageClass() != VarDecl::PrivateExtern) { 2338 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2339 << Var->getDeclName() 2340 << SourceRange(Var->getLocation(), Var->getLocation()); 2341 Var->setInvalidDecl(); 2342 return; 2343 } 2344 2345 // C++ [dcl.init]p9: 2346 // 2347 // If no initializer is specified for an object, and the object 2348 // is of (possibly cv-qualified) non-POD class type (or array 2349 // thereof), the object shall be default-initialized; if the 2350 // object is of const-qualified type, the underlying class type 2351 // shall have a user-declared default constructor. 2352 if (getLangOptions().CPlusPlus) { 2353 QualType InitType = Type; 2354 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2355 InitType = Array->getElementType(); 2356 if (Var->getStorageClass() != VarDecl::Extern && 2357 Var->getStorageClass() != VarDecl::PrivateExtern && 2358 InitType->isRecordType()) { 2359 const CXXConstructorDecl *Constructor 2360 = PerformInitializationByConstructor(InitType, 0, 0, 2361 Var->getLocation(), 2362 SourceRange(Var->getLocation(), 2363 Var->getLocation()), 2364 Var->getDeclName(), 2365 IK_Default); 2366 if (!Constructor) 2367 Var->setInvalidDecl(); 2368 } 2369 } 2370 2371#if 0 2372 // FIXME: Temporarily disabled because we are not properly parsing 2373 // linkage specifications on declarations, e.g., 2374 // 2375 // extern "C" const CGPoint CGPointerZero; 2376 // 2377 // C++ [dcl.init]p9: 2378 // 2379 // If no initializer is specified for an object, and the 2380 // object is of (possibly cv-qualified) non-POD class type (or 2381 // array thereof), the object shall be default-initialized; if 2382 // the object is of const-qualified type, the underlying class 2383 // type shall have a user-declared default 2384 // constructor. Otherwise, if no initializer is specified for 2385 // an object, the object and its subobjects, if any, have an 2386 // indeterminate initial value; if the object or any of its 2387 // subobjects are of const-qualified type, the program is 2388 // ill-formed. 2389 // 2390 // This isn't technically an error in C, so we don't diagnose it. 2391 // 2392 // FIXME: Actually perform the POD/user-defined default 2393 // constructor check. 2394 if (getLangOptions().CPlusPlus && 2395 Context.getCanonicalType(Type).isConstQualified() && 2396 Var->getStorageClass() != VarDecl::Extern) 2397 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2398 << Var->getName() 2399 << SourceRange(Var->getLocation(), Var->getLocation()); 2400#endif 2401 } 2402} 2403 2404/// The declarators are chained together backwards, reverse the list. 2405Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2406 // Often we have single declarators, handle them quickly. 2407 Decl *GroupDecl = static_cast<Decl*>(group); 2408 if (GroupDecl == 0) 2409 return 0; 2410 2411 Decl *Group = dyn_cast<Decl>(GroupDecl); 2412 Decl *NewGroup = 0; 2413 if (Group->getNextDeclarator() == 0) 2414 NewGroup = Group; 2415 else { // reverse the list. 2416 while (Group) { 2417 Decl *Next = Group->getNextDeclarator(); 2418 Group->setNextDeclarator(NewGroup); 2419 NewGroup = Group; 2420 Group = Next; 2421 } 2422 } 2423 // Perform semantic analysis that depends on having fully processed both 2424 // the declarator and initializer. 2425 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2426 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2427 if (!IDecl) 2428 continue; 2429 QualType T = IDecl->getType(); 2430 2431 if (T->isVariableArrayType()) { 2432 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2433 2434 // FIXME: This won't give the correct result for 2435 // int a[10][n]; 2436 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2437 if (IDecl->isFileVarDecl()) { 2438 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2439 SizeRange; 2440 2441 IDecl->setInvalidDecl(); 2442 } else { 2443 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2444 // static storage duration, it shall not have a variable length array. 2445 if (IDecl->getStorageClass() == VarDecl::Static) { 2446 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2447 << SizeRange; 2448 IDecl->setInvalidDecl(); 2449 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2450 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2451 << SizeRange; 2452 IDecl->setInvalidDecl(); 2453 } 2454 } 2455 } else if (T->isVariablyModifiedType()) { 2456 if (IDecl->isFileVarDecl()) { 2457 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2458 IDecl->setInvalidDecl(); 2459 } else { 2460 if (IDecl->getStorageClass() == VarDecl::Extern) { 2461 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2462 IDecl->setInvalidDecl(); 2463 } 2464 } 2465 } 2466 2467 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2468 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2469 if (IDecl->isBlockVarDecl() && 2470 IDecl->getStorageClass() != VarDecl::Extern) { 2471 if (!IDecl->isInvalidDecl() && 2472 DiagnoseIncompleteType(IDecl->getLocation(), T, 2473 diag::err_typecheck_decl_incomplete_type)) 2474 IDecl->setInvalidDecl(); 2475 } 2476 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2477 // object that has file scope without an initializer, and without a 2478 // storage-class specifier or with the storage-class specifier "static", 2479 // constitutes a tentative definition. Note: A tentative definition with 2480 // external linkage is valid (C99 6.2.2p5). 2481 if (isTentativeDefinition(IDecl)) { 2482 if (T->isIncompleteArrayType()) { 2483 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2484 // array to be completed. Don't issue a diagnostic. 2485 } else if (!IDecl->isInvalidDecl() && 2486 DiagnoseIncompleteType(IDecl->getLocation(), T, 2487 diag::err_typecheck_decl_incomplete_type)) 2488 // C99 6.9.2p3: If the declaration of an identifier for an object is 2489 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2490 // declared type shall not be an incomplete type. 2491 IDecl->setInvalidDecl(); 2492 } 2493 if (IDecl->isFileVarDecl()) 2494 CheckForFileScopedRedefinitions(S, IDecl); 2495 } 2496 return NewGroup; 2497} 2498 2499/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2500/// to introduce parameters into function prototype scope. 2501Sema::DeclTy * 2502Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2503 const DeclSpec &DS = D.getDeclSpec(); 2504 2505 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2506 VarDecl::StorageClass StorageClass = VarDecl::None; 2507 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2508 StorageClass = VarDecl::Register; 2509 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2510 Diag(DS.getStorageClassSpecLoc(), 2511 diag::err_invalid_storage_class_in_func_decl); 2512 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2513 } 2514 if (DS.isThreadSpecified()) { 2515 Diag(DS.getThreadSpecLoc(), 2516 diag::err_invalid_storage_class_in_func_decl); 2517 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2518 } 2519 2520 // Check that there are no default arguments inside the type of this 2521 // parameter (C++ only). 2522 if (getLangOptions().CPlusPlus) 2523 CheckExtraCXXDefaultArguments(D); 2524 2525 // In this context, we *do not* check D.getInvalidType(). If the declarator 2526 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2527 // though it will not reflect the user specified type. 2528 QualType parmDeclType = GetTypeForDeclarator(D, S); 2529 2530 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2531 2532 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2533 // Can this happen for params? We already checked that they don't conflict 2534 // among each other. Here they can only shadow globals, which is ok. 2535 IdentifierInfo *II = D.getIdentifier(); 2536 if (II) { 2537 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2538 if (PrevDecl->isTemplateParameter()) { 2539 // Maybe we will complain about the shadowed template parameter. 2540 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2541 // Just pretend that we didn't see the previous declaration. 2542 PrevDecl = 0; 2543 } else if (S->isDeclScope(PrevDecl)) { 2544 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2545 2546 // Recover by removing the name 2547 II = 0; 2548 D.SetIdentifier(0, D.getIdentifierLoc()); 2549 } 2550 } 2551 } 2552 2553 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2554 // Doing the promotion here has a win and a loss. The win is the type for 2555 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2556 // code generator). The loss is the orginal type isn't preserved. For example: 2557 // 2558 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2559 // int blockvardecl[5]; 2560 // sizeof(parmvardecl); // size == 4 2561 // sizeof(blockvardecl); // size == 20 2562 // } 2563 // 2564 // For expressions, all implicit conversions are captured using the 2565 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2566 // 2567 // FIXME: If a source translation tool needs to see the original type, then 2568 // we need to consider storing both types (in ParmVarDecl)... 2569 // 2570 if (parmDeclType->isArrayType()) { 2571 // int x[restrict 4] -> int *restrict 2572 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2573 } else if (parmDeclType->isFunctionType()) 2574 parmDeclType = Context.getPointerType(parmDeclType); 2575 2576 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2577 D.getIdentifierLoc(), II, 2578 parmDeclType, StorageClass, 2579 0); 2580 2581 if (D.getInvalidType()) 2582 New->setInvalidDecl(); 2583 2584 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2585 if (D.getCXXScopeSpec().isSet()) { 2586 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2587 << D.getCXXScopeSpec().getRange(); 2588 New->setInvalidDecl(); 2589 } 2590 2591 // Add the parameter declaration into this scope. 2592 S->AddDecl(New); 2593 if (II) 2594 IdResolver.AddDecl(New); 2595 2596 ProcessDeclAttributes(New, D); 2597 return New; 2598 2599} 2600 2601void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2602 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2603 "Not a function declarator!"); 2604 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2605 2606 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2607 // for a K&R function. 2608 if (!FTI.hasPrototype) { 2609 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2610 if (FTI.ArgInfo[i].Param == 0) { 2611 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2612 << FTI.ArgInfo[i].Ident; 2613 // Implicitly declare the argument as type 'int' for lack of a better 2614 // type. 2615 DeclSpec DS; 2616 const char* PrevSpec; // unused 2617 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2618 PrevSpec); 2619 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2620 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2621 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2622 } 2623 } 2624 } 2625} 2626 2627Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2628 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2629 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2630 "Not a function declarator!"); 2631 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2632 2633 if (FTI.hasPrototype) { 2634 // FIXME: Diagnose arguments without names in C. 2635 } 2636 2637 Scope *ParentScope = FnBodyScope->getParent(); 2638 2639 return ActOnStartOfFunctionDef(FnBodyScope, 2640 ActOnDeclarator(ParentScope, D, 0, 2641 /*IsFunctionDefinition=*/true)); 2642} 2643 2644Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2645 Decl *decl = static_cast<Decl*>(D); 2646 FunctionDecl *FD = cast<FunctionDecl>(decl); 2647 2648 // See if this is a redefinition. 2649 const FunctionDecl *Definition; 2650 if (FD->getBody(Definition)) { 2651 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2652 Diag(Definition->getLocation(), diag::note_previous_definition); 2653 } 2654 2655 PushDeclContext(FnBodyScope, FD); 2656 2657 // Check the validity of our function parameters 2658 CheckParmsForFunctionDef(FD); 2659 2660 // Introduce our parameters into the function scope 2661 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2662 ParmVarDecl *Param = FD->getParamDecl(p); 2663 Param->setOwningFunction(FD); 2664 2665 // If this has an identifier, add it to the scope stack. 2666 if (Param->getIdentifier()) 2667 PushOnScopeChains(Param, FnBodyScope); 2668 } 2669 2670 // Checking attributes of current function definition 2671 // dllimport attribute. 2672 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2673 // dllimport attribute cannot be applied to definition. 2674 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2675 Diag(FD->getLocation(), 2676 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2677 << "dllimport"; 2678 FD->setInvalidDecl(); 2679 return FD; 2680 } else { 2681 // If a symbol previously declared dllimport is later defined, the 2682 // attribute is ignored in subsequent references, and a warning is 2683 // emitted. 2684 Diag(FD->getLocation(), 2685 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2686 << FD->getNameAsCString() << "dllimport"; 2687 } 2688 } 2689 return FD; 2690} 2691 2692Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2693 Decl *dcl = static_cast<Decl *>(D); 2694 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2695 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2696 FD->setBody(Body); 2697 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2698 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2699 MD->setBody((Stmt*)Body); 2700 } else 2701 return 0; 2702 PopDeclContext(); 2703 // Verify and clean out per-function state. 2704 2705 // Check goto/label use. 2706 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2707 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2708 // Verify that we have no forward references left. If so, there was a goto 2709 // or address of a label taken, but no definition of it. Label fwd 2710 // definitions are indicated with a null substmt. 2711 if (I->second->getSubStmt() == 0) { 2712 LabelStmt *L = I->second; 2713 // Emit error. 2714 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2715 2716 // At this point, we have gotos that use the bogus label. Stitch it into 2717 // the function body so that they aren't leaked and that the AST is well 2718 // formed. 2719 if (Body) { 2720 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2721 cast<CompoundStmt>(Body)->push_back(L); 2722 } else { 2723 // The whole function wasn't parsed correctly, just delete this. 2724 delete L; 2725 } 2726 } 2727 } 2728 LabelMap.clear(); 2729 2730 return D; 2731} 2732 2733/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2734/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2735NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2736 IdentifierInfo &II, Scope *S) { 2737 // Extension in C99. Legal in C90, but warn about it. 2738 if (getLangOptions().C99) 2739 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2740 else 2741 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2742 2743 // FIXME: handle stuff like: 2744 // void foo() { extern float X(); } 2745 // void bar() { X(); } <-- implicit decl for X in another scope. 2746 2747 // Set a Declarator for the implicit definition: int foo(); 2748 const char *Dummy; 2749 DeclSpec DS; 2750 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2751 Error = Error; // Silence warning. 2752 assert(!Error && "Error setting up implicit decl!"); 2753 Declarator D(DS, Declarator::BlockContext); 2754 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D)); 2755 D.SetIdentifier(&II, Loc); 2756 2757 // Insert this function into translation-unit scope. 2758 2759 DeclContext *PrevDC = CurContext; 2760 CurContext = Context.getTranslationUnitDecl(); 2761 2762 FunctionDecl *FD = 2763 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2764 FD->setImplicit(); 2765 2766 CurContext = PrevDC; 2767 2768 return FD; 2769} 2770 2771 2772TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2773 Decl *LastDeclarator) { 2774 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2775 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2776 2777 // Scope manipulation handled by caller. 2778 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2779 D.getIdentifierLoc(), 2780 D.getIdentifier(), 2781 T); 2782 NewTD->setNextDeclarator(LastDeclarator); 2783 if (D.getInvalidType()) 2784 NewTD->setInvalidDecl(); 2785 return NewTD; 2786} 2787 2788/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2789/// former case, Name will be non-null. In the later case, Name will be null. 2790/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2791/// reference/declaration/definition of a tag. 2792/// 2793/// This creates and returns template declarations if any template parameter 2794/// lists are given. 2795Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2796 SourceLocation KWLoc, const CXXScopeSpec &SS, 2797 IdentifierInfo *Name, SourceLocation NameLoc, 2798 AttributeList *Attr, 2799 MultiTemplateParamsArg TemplateParameterLists) { 2800 // If this is not a definition, it must have a name. 2801 assert((Name != 0 || TK == TK_Definition) && 2802 "Nameless record must be a definition!"); 2803 assert((TemplateParameterLists.size() == 0 || TK != TK_Reference) && 2804 "Can't have a reference to a template"); 2805 assert((TemplateParameterLists.size() == 0 || 2806 TagSpec != DeclSpec::TST_enum) && 2807 "No such thing as an enum template"); 2808 2809 TagDecl::TagKind Kind; 2810 switch (TagSpec) { 2811 default: assert(0 && "Unknown tag type!"); 2812 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2813 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2814 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2815 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2816 } 2817 2818 DeclContext *SearchDC = CurContext; 2819 DeclContext *DC = CurContext; 2820 NamedDecl *PrevDecl = 0; 2821 TemplateDecl *PrevTemplate = 0; 2822 2823 bool Invalid = false; 2824 2825 if (Name && SS.isNotEmpty()) { 2826 // We have a nested-name tag ('struct foo::bar'). 2827 2828 // Check for invalid 'foo::'. 2829 if (SS.isInvalid()) { 2830 Name = 0; 2831 goto CreateNewDecl; 2832 } 2833 2834 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2835 SearchDC = DC; 2836 // Look-up name inside 'foo::'. 2837 PrevDecl = dyn_cast_or_null<TagDecl>( 2838 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 2839 2840 // A tag 'foo::bar' must already exist. 2841 if (PrevDecl == 0) { 2842 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2843 Name = 0; 2844 goto CreateNewDecl; 2845 } 2846 } else if (Name) { 2847 // If this is a named struct, check to see if there was a previous forward 2848 // declaration or definition. 2849 // FIXME: We're looking into outer scopes here, even when we 2850 // shouldn't be. Doing so can result in ambiguities that we 2851 // shouldn't be diagnosing. 2852 LookupResult R = LookupName(S, Name, LookupTagName, 2853 /*RedeclarationOnly=*/(TK != TK_Reference)); 2854 if (R.isAmbiguous()) { 2855 DiagnoseAmbiguousLookup(R, Name, NameLoc); 2856 // FIXME: This is not best way to recover from case like: 2857 // 2858 // struct S s; 2859 // 2860 // causes needless err_ovl_no_viable_function_in_init latter. 2861 Name = 0; 2862 PrevDecl = 0; 2863 Invalid = true; 2864 } 2865 else 2866 PrevDecl = R; 2867 2868 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2869 // FIXME: This makes sure that we ignore the contexts associated 2870 // with C structs, unions, and enums when looking for a matching 2871 // tag declaration or definition. See the similar lookup tweak 2872 // in Sema::LookupName; is there a better way to deal with this? 2873 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2874 SearchDC = SearchDC->getParent(); 2875 } 2876 } 2877 2878 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2879 // Maybe we will complain about the shadowed template parameter. 2880 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2881 // Just pretend that we didn't see the previous declaration. 2882 PrevDecl = 0; 2883 } 2884 2885 if (PrevDecl) { 2886 // If we found a template, keep track of the template and its 2887 // underlying declaration. 2888 if ((PrevTemplate = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl))) 2889 PrevDecl = PrevTemplate->getTemplatedDecl(); 2890 2891 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2892 // If this is a use of a previous tag, or if the tag is already declared 2893 // in the same scope (so that the definition/declaration completes or 2894 // rementions the tag), reuse the decl. 2895 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2896 // Make sure that this wasn't declared as an enum and now used as a 2897 // struct or something similar. 2898 if (PrevTagDecl->getTagKind() != Kind) { 2899 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2900 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2901 // Recover by making this an anonymous redefinition. 2902 Name = 0; 2903 PrevDecl = 0; 2904 Invalid = true; 2905 // FIXME: Add template/non-template redecl check 2906 } else { 2907 // If this is a use, just return the declaration we found. 2908 2909 // FIXME: In the future, return a variant or some other clue 2910 // for the consumer of this Decl to know it doesn't own it. 2911 // For our current ASTs this shouldn't be a problem, but will 2912 // need to be changed with DeclGroups. 2913 if (TK == TK_Reference) 2914 return PrevDecl; 2915 2916 // Diagnose attempts to redefine a tag. 2917 if (TK == TK_Definition) { 2918 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2919 Diag(NameLoc, diag::err_redefinition) << Name; 2920 Diag(Def->getLocation(), diag::note_previous_definition); 2921 // If this is a redefinition, recover by making this 2922 // struct be anonymous, which will make any later 2923 // references get the previous definition. 2924 Name = 0; 2925 PrevDecl = 0; 2926 Invalid = true; 2927 } else { 2928 // If the type is currently being defined, complain 2929 // about a nested redefinition. 2930 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2931 if (Tag->isBeingDefined()) { 2932 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2933 Diag(PrevTagDecl->getLocation(), 2934 diag::note_previous_definition); 2935 Name = 0; 2936 PrevDecl = 0; 2937 Invalid = true; 2938 } 2939 } 2940 2941 // Okay, this is definition of a previously declared or referenced 2942 // tag PrevDecl. We're going to create a new Decl for it. 2943 } 2944 } 2945 // If we get here we have (another) forward declaration or we 2946 // have a definition. Just create a new decl. 2947 } else { 2948 // If we get here, this is a definition of a new tag type in a nested 2949 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2950 // new decl/type. We set PrevDecl to NULL so that the entities 2951 // have distinct types. 2952 PrevDecl = 0; 2953 } 2954 // If we get here, we're going to create a new Decl. If PrevDecl 2955 // is non-NULL, it's a definition of the tag declared by 2956 // PrevDecl. If it's NULL, we have a new definition. 2957 } else { 2958 // PrevDecl is a namespace, template, or anything else 2959 // that lives in the IDNS_Tag identifier namespace. 2960 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2961 // The tag name clashes with a namespace name, issue an error and 2962 // recover by making this tag be anonymous. 2963 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2964 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2965 Name = 0; 2966 PrevDecl = 0; 2967 Invalid = true; 2968 } else { 2969 // The existing declaration isn't relevant to us; we're in a 2970 // new scope, so clear out the previous declaration. 2971 PrevDecl = 0; 2972 } 2973 } 2974 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2975 (Kind != TagDecl::TK_enum)) { 2976 // C++ [basic.scope.pdecl]p5: 2977 // -- for an elaborated-type-specifier of the form 2978 // 2979 // class-key identifier 2980 // 2981 // if the elaborated-type-specifier is used in the 2982 // decl-specifier-seq or parameter-declaration-clause of a 2983 // function defined in namespace scope, the identifier is 2984 // declared as a class-name in the namespace that contains 2985 // the declaration; otherwise, except as a friend 2986 // declaration, the identifier is declared in the smallest 2987 // non-class, non-function-prototype scope that contains the 2988 // declaration. 2989 // 2990 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2991 // C structs and unions. 2992 2993 // Find the context where we'll be declaring the tag. 2994 // FIXME: We would like to maintain the current DeclContext as the 2995 // lexical context, 2996 while (SearchDC->isRecord()) 2997 SearchDC = SearchDC->getParent(); 2998 2999 // Find the scope where we'll be declaring the tag. 3000 while (S->isClassScope() || 3001 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3002 ((S->getFlags() & Scope::DeclScope) == 0) || 3003 (S->getEntity() && 3004 ((DeclContext *)S->getEntity())->isTransparentContext())) 3005 S = S->getParent(); 3006 } 3007 3008CreateNewDecl: 3009 3010 // If there is an identifier, use the location of the identifier as the 3011 // location of the decl, otherwise use the location of the struct/union 3012 // keyword. 3013 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3014 3015 // Otherwise, create a new declaration. If there is a previous 3016 // declaration of the same entity, the two will be linked via 3017 // PrevDecl. 3018 TagDecl *New; 3019 ClassTemplateDecl *NewTemplate = 0; 3020 3021 if (Kind == TagDecl::TK_enum) { 3022 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3023 // enum X { A, B, C } D; D should chain to X. 3024 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3025 cast_or_null<EnumDecl>(PrevDecl)); 3026 // If this is an undefined enum, warn. 3027 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3028 } else { 3029 // struct/union/class 3030 3031 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3032 // struct X { int A; } D; D should chain to X. 3033 if (getLangOptions().CPlusPlus) { 3034 // FIXME: Look for a way to use RecordDecl for simple structs. 3035 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3036 cast_or_null<CXXRecordDecl>(PrevDecl)); 3037 3038 // If there's are template parameters, then this must be a class 3039 // template. Create the template decl node also. 3040 // FIXME: Do we always create template decls? We may not for forward 3041 // declarations. 3042 // FIXME: What are we actually going to do with the template decl? 3043 if (TemplateParameterLists.size() > 0) { 3044 // FIXME: The allocation of the parameters is probably incorrect. 3045 // FIXME: Does the TemplateDecl have the same name as the class? 3046 TemplateParameterList *Params = 3047 TemplateParameterList::Create(Context, 3048 (Decl **)TemplateParameterLists.get(), 3049 TemplateParameterLists.size()); 3050 NewTemplate = ClassTemplateDecl::Create(Context, DC, Loc, 3051 DeclarationName(Name), Params, 3052 New); 3053 } 3054 } else 3055 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3056 cast_or_null<RecordDecl>(PrevDecl)); 3057 } 3058 3059 if (Kind != TagDecl::TK_enum) { 3060 // Handle #pragma pack: if the #pragma pack stack has non-default 3061 // alignment, make up a packed attribute for this decl. These 3062 // attributes are checked when the ASTContext lays out the 3063 // structure. 3064 // 3065 // It is important for implementing the correct semantics that this 3066 // happen here (in act on tag decl). The #pragma pack stack is 3067 // maintained as a result of parser callbacks which can occur at 3068 // many points during the parsing of a struct declaration (because 3069 // the #pragma tokens are effectively skipped over during the 3070 // parsing of the struct). 3071 if (unsigned Alignment = PackContext.getAlignment()) 3072 New->addAttr(new PackedAttr(Alignment * 8)); 3073 } 3074 3075 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3076 // C++ [dcl.typedef]p3: 3077 // [...] Similarly, in a given scope, a class or enumeration 3078 // shall not be declared with the same name as a typedef-name 3079 // that is declared in that scope and refers to a type other 3080 // than the class or enumeration itself. 3081 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3082 TypedefDecl *PrevTypedef = 0; 3083 if (Lookup.getKind() == LookupResult::Found) 3084 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3085 3086 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3087 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3088 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3089 Diag(Loc, diag::err_tag_definition_of_typedef) 3090 << Context.getTypeDeclType(New) 3091 << PrevTypedef->getUnderlyingType(); 3092 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3093 Invalid = true; 3094 } 3095 } 3096 3097 if (Invalid) 3098 New->setInvalidDecl(); 3099 3100 if (Attr) 3101 ProcessDeclAttributeList(New, Attr); 3102 3103 // If we're declaring or defining a tag in function prototype scope 3104 // in C, note that this type can only be used within the function. 3105 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3106 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3107 3108 // Set the lexical context. If the tag has a C++ scope specifier, the 3109 // lexical context will be different from the semantic context. 3110 New->setLexicalDeclContext(CurContext); 3111 3112 if (TK == TK_Definition) 3113 New->startDefinition(); 3114 3115 // If this has an identifier, add it to the scope stack. 3116 if (Name) { 3117 S = getNonFieldDeclScope(S); 3118 PushOnScopeChains(New, S); 3119 } else { 3120 CurContext->addDecl(New); 3121 } 3122 3123 return New; 3124} 3125 3126void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3127 AdjustDeclIfTemplate(TagD); 3128 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3129 3130 // Enter the tag context. 3131 PushDeclContext(S, Tag); 3132 3133 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3134 FieldCollector->StartClass(); 3135 3136 if (Record->getIdentifier()) { 3137 // C++ [class]p2: 3138 // [...] The class-name is also inserted into the scope of the 3139 // class itself; this is known as the injected-class-name. For 3140 // purposes of access checking, the injected-class-name is treated 3141 // as if it were a public member name. 3142 RecordDecl *InjectedClassName 3143 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3144 CurContext, Record->getLocation(), 3145 Record->getIdentifier(), Record); 3146 InjectedClassName->setImplicit(); 3147 PushOnScopeChains(InjectedClassName, S); 3148 } 3149 } 3150} 3151 3152void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3153 AdjustDeclIfTemplate(TagD); 3154 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3155 3156 if (isa<CXXRecordDecl>(Tag)) 3157 FieldCollector->FinishClass(); 3158 3159 // Exit this scope of this tag's definition. 3160 PopDeclContext(); 3161 3162 // Notify the consumer that we've defined a tag. 3163 Consumer.HandleTagDeclDefinition(Tag); 3164} 3165 3166/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3167/// types into constant array types in certain situations which would otherwise 3168/// be errors (for GCC compatibility). 3169static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3170 ASTContext &Context) { 3171 // This method tries to turn a variable array into a constant 3172 // array even when the size isn't an ICE. This is necessary 3173 // for compatibility with code that depends on gcc's buggy 3174 // constant expression folding, like struct {char x[(int)(char*)2];} 3175 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3176 if (!VLATy) return QualType(); 3177 3178 Expr::EvalResult EvalResult; 3179 if (!VLATy->getSizeExpr() || 3180 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3181 return QualType(); 3182 3183 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3184 llvm::APSInt &Res = EvalResult.Val.getInt(); 3185 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3186 return Context.getConstantArrayType(VLATy->getElementType(), 3187 Res, ArrayType::Normal, 0); 3188 return QualType(); 3189} 3190 3191bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3192 QualType FieldTy, const Expr *BitWidth) { 3193 // FIXME: 6.7.2.1p4 - verify the field type. 3194 3195 llvm::APSInt Value; 3196 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3197 return true; 3198 3199 // Zero-width bitfield is ok for anonymous field. 3200 if (Value == 0 && FieldName) 3201 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3202 3203 if (Value.isNegative()) 3204 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3205 3206 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3207 // FIXME: We won't need the 0 size once we check that the field type is valid. 3208 if (TypeSize && Value.getZExtValue() > TypeSize) 3209 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3210 << FieldName << (unsigned)TypeSize; 3211 3212 return false; 3213} 3214 3215/// ActOnField - Each field of a struct/union/class is passed into this in order 3216/// to create a FieldDecl object for it. 3217Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3218 SourceLocation DeclStart, 3219 Declarator &D, ExprTy *BitfieldWidth) { 3220 IdentifierInfo *II = D.getIdentifier(); 3221 Expr *BitWidth = (Expr*)BitfieldWidth; 3222 SourceLocation Loc = DeclStart; 3223 RecordDecl *Record = (RecordDecl *)TagD; 3224 if (II) Loc = D.getIdentifierLoc(); 3225 3226 // FIXME: Unnamed fields can be handled in various different ways, for 3227 // example, unnamed unions inject all members into the struct namespace! 3228 3229 QualType T = GetTypeForDeclarator(D, S); 3230 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3231 bool InvalidDecl = false; 3232 3233 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3234 // than a variably modified type. 3235 if (T->isVariablyModifiedType()) { 3236 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3237 if (!FixedTy.isNull()) { 3238 Diag(Loc, diag::warn_illegal_constant_array_size); 3239 T = FixedTy; 3240 } else { 3241 Diag(Loc, diag::err_typecheck_field_variable_size); 3242 T = Context.IntTy; 3243 InvalidDecl = true; 3244 } 3245 } 3246 3247 if (BitWidth) { 3248 if (VerifyBitField(Loc, II, T, BitWidth)) 3249 InvalidDecl = true; 3250 } else { 3251 // Not a bitfield. 3252 3253 // validate II. 3254 3255 } 3256 3257 // FIXME: Chain fielddecls together. 3258 FieldDecl *NewFD; 3259 3260 NewFD = FieldDecl::Create(Context, Record, 3261 Loc, II, T, BitWidth, 3262 D.getDeclSpec().getStorageClassSpec() == 3263 DeclSpec::SCS_mutable); 3264 3265 if (II) { 3266 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3267 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3268 && !isa<TagDecl>(PrevDecl)) { 3269 Diag(Loc, diag::err_duplicate_member) << II; 3270 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3271 NewFD->setInvalidDecl(); 3272 Record->setInvalidDecl(); 3273 } 3274 } 3275 3276 if (getLangOptions().CPlusPlus) { 3277 CheckExtraCXXDefaultArguments(D); 3278 if (!T->isPODType()) 3279 cast<CXXRecordDecl>(Record)->setPOD(false); 3280 } 3281 3282 ProcessDeclAttributes(NewFD, D); 3283 3284 if (D.getInvalidType() || InvalidDecl) 3285 NewFD->setInvalidDecl(); 3286 3287 if (II) { 3288 PushOnScopeChains(NewFD, S); 3289 } else 3290 Record->addDecl(NewFD); 3291 3292 return NewFD; 3293} 3294 3295/// TranslateIvarVisibility - Translate visibility from a token ID to an 3296/// AST enum value. 3297static ObjCIvarDecl::AccessControl 3298TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3299 switch (ivarVisibility) { 3300 default: assert(0 && "Unknown visitibility kind"); 3301 case tok::objc_private: return ObjCIvarDecl::Private; 3302 case tok::objc_public: return ObjCIvarDecl::Public; 3303 case tok::objc_protected: return ObjCIvarDecl::Protected; 3304 case tok::objc_package: return ObjCIvarDecl::Package; 3305 } 3306} 3307 3308/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3309/// in order to create an IvarDecl object for it. 3310Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3311 SourceLocation DeclStart, 3312 Declarator &D, ExprTy *BitfieldWidth, 3313 tok::ObjCKeywordKind Visibility) { 3314 3315 IdentifierInfo *II = D.getIdentifier(); 3316 Expr *BitWidth = (Expr*)BitfieldWidth; 3317 SourceLocation Loc = DeclStart; 3318 if (II) Loc = D.getIdentifierLoc(); 3319 3320 // FIXME: Unnamed fields can be handled in various different ways, for 3321 // example, unnamed unions inject all members into the struct namespace! 3322 3323 QualType T = GetTypeForDeclarator(D, S); 3324 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3325 bool InvalidDecl = false; 3326 3327 if (BitWidth) { 3328 // TODO: Validate. 3329 //printf("WARNING: BITFIELDS IGNORED!\n"); 3330 3331 // 6.7.2.1p3 3332 // 6.7.2.1p4 3333 3334 } else { 3335 // Not a bitfield. 3336 3337 // validate II. 3338 3339 } 3340 3341 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3342 // than a variably modified type. 3343 if (T->isVariablyModifiedType()) { 3344 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3345 InvalidDecl = true; 3346 } 3347 3348 // Get the visibility (access control) for this ivar. 3349 ObjCIvarDecl::AccessControl ac = 3350 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3351 : ObjCIvarDecl::None; 3352 3353 // Construct the decl. 3354 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3355 (Expr *)BitfieldWidth); 3356 3357 if (II) { 3358 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3359 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3360 && !isa<TagDecl>(PrevDecl)) { 3361 Diag(Loc, diag::err_duplicate_member) << II; 3362 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3363 NewID->setInvalidDecl(); 3364 } 3365 } 3366 3367 // Process attributes attached to the ivar. 3368 ProcessDeclAttributes(NewID, D); 3369 3370 if (D.getInvalidType() || InvalidDecl) 3371 NewID->setInvalidDecl(); 3372 3373 if (II) { 3374 // FIXME: When interfaces are DeclContexts, we'll need to add 3375 // these to the interface. 3376 S->AddDecl(NewID); 3377 IdResolver.AddDecl(NewID); 3378 } 3379 3380 return NewID; 3381} 3382 3383void Sema::ActOnFields(Scope* S, 3384 SourceLocation RecLoc, DeclTy *RecDecl, 3385 DeclTy **Fields, unsigned NumFields, 3386 SourceLocation LBrac, SourceLocation RBrac, 3387 AttributeList *Attr) { 3388 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3389 assert(EnclosingDecl && "missing record or interface decl"); 3390 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3391 3392 // Verify that all the fields are okay. 3393 unsigned NumNamedMembers = 0; 3394 llvm::SmallVector<FieldDecl*, 32> RecFields; 3395 3396 for (unsigned i = 0; i != NumFields; ++i) { 3397 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3398 assert(FD && "missing field decl"); 3399 3400 // Get the type for the field. 3401 Type *FDTy = FD->getType().getTypePtr(); 3402 3403 if (!FD->isAnonymousStructOrUnion()) { 3404 // Remember all fields written by the user. 3405 RecFields.push_back(FD); 3406 } 3407 3408 // C99 6.7.2.1p2 - A field may not be a function type. 3409 if (FDTy->isFunctionType()) { 3410 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3411 << FD->getDeclName(); 3412 FD->setInvalidDecl(); 3413 EnclosingDecl->setInvalidDecl(); 3414 continue; 3415 } 3416 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3417 if (FDTy->isIncompleteType()) { 3418 if (!Record) { // Incomplete ivar type is always an error. 3419 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3420 diag::err_field_incomplete); 3421 FD->setInvalidDecl(); 3422 EnclosingDecl->setInvalidDecl(); 3423 continue; 3424 } 3425 if (i != NumFields-1 || // ... that the last member ... 3426 !Record->isStruct() || // ... of a structure ... 3427 !FDTy->isArrayType()) { //... may have incomplete array type. 3428 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3429 diag::err_field_incomplete); 3430 FD->setInvalidDecl(); 3431 EnclosingDecl->setInvalidDecl(); 3432 continue; 3433 } 3434 if (NumNamedMembers < 1) { //... must have more than named member ... 3435 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3436 << FD->getDeclName(); 3437 FD->setInvalidDecl(); 3438 EnclosingDecl->setInvalidDecl(); 3439 continue; 3440 } 3441 // Okay, we have a legal flexible array member at the end of the struct. 3442 if (Record) 3443 Record->setHasFlexibleArrayMember(true); 3444 } 3445 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3446 /// field of another structure or the element of an array. 3447 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3448 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3449 // If this is a member of a union, then entire union becomes "flexible". 3450 if (Record && Record->isUnion()) { 3451 Record->setHasFlexibleArrayMember(true); 3452 } else { 3453 // If this is a struct/class and this is not the last element, reject 3454 // it. Note that GCC supports variable sized arrays in the middle of 3455 // structures. 3456 if (i != NumFields-1) { 3457 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3458 << FD->getDeclName(); 3459 FD->setInvalidDecl(); 3460 EnclosingDecl->setInvalidDecl(); 3461 continue; 3462 } 3463 // We support flexible arrays at the end of structs in other structs 3464 // as an extension. 3465 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3466 << FD->getDeclName(); 3467 if (Record) 3468 Record->setHasFlexibleArrayMember(true); 3469 } 3470 } 3471 } 3472 /// A field cannot be an Objective-c object 3473 if (FDTy->isObjCInterfaceType()) { 3474 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3475 << FD->getDeclName(); 3476 FD->setInvalidDecl(); 3477 EnclosingDecl->setInvalidDecl(); 3478 continue; 3479 } 3480 // Keep track of the number of named members. 3481 if (FD->getIdentifier()) 3482 ++NumNamedMembers; 3483 } 3484 3485 // Okay, we successfully defined 'Record'. 3486 if (Record) { 3487 Record->completeDefinition(Context); 3488 } else { 3489 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3490 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3491 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3492 // Must enforce the rule that ivars in the base classes may not be 3493 // duplicates. 3494 if (ID->getSuperClass()) { 3495 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3496 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3497 ObjCIvarDecl* Ivar = (*IVI); 3498 IdentifierInfo *II = Ivar->getIdentifier(); 3499 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3500 if (prevIvar) { 3501 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3502 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3503 } 3504 } 3505 } 3506 } 3507 else if (ObjCImplementationDecl *IMPDecl = 3508 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3509 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3510 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3511 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3512 } 3513 } 3514 3515 if (Attr) 3516 ProcessDeclAttributeList(Record, Attr); 3517} 3518 3519Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3520 DeclTy *lastEnumConst, 3521 SourceLocation IdLoc, IdentifierInfo *Id, 3522 SourceLocation EqualLoc, ExprTy *val) { 3523 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3524 EnumConstantDecl *LastEnumConst = 3525 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3526 Expr *Val = static_cast<Expr*>(val); 3527 3528 // The scope passed in may not be a decl scope. Zip up the scope tree until 3529 // we find one that is. 3530 S = getNonFieldDeclScope(S); 3531 3532 // Verify that there isn't already something declared with this name in this 3533 // scope. 3534 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3535 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3536 // Maybe we will complain about the shadowed template parameter. 3537 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3538 // Just pretend that we didn't see the previous declaration. 3539 PrevDecl = 0; 3540 } 3541 3542 if (PrevDecl) { 3543 // When in C++, we may get a TagDecl with the same name; in this case the 3544 // enum constant will 'hide' the tag. 3545 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3546 "Received TagDecl when not in C++!"); 3547 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3548 if (isa<EnumConstantDecl>(PrevDecl)) 3549 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3550 else 3551 Diag(IdLoc, diag::err_redefinition) << Id; 3552 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3553 delete Val; 3554 return 0; 3555 } 3556 } 3557 3558 llvm::APSInt EnumVal(32); 3559 QualType EltTy; 3560 if (Val) { 3561 // Make sure to promote the operand type to int. 3562 UsualUnaryConversions(Val); 3563 3564 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3565 SourceLocation ExpLoc; 3566 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3567 delete Val; 3568 Val = 0; // Just forget about it. 3569 } else { 3570 EltTy = Val->getType(); 3571 } 3572 } 3573 3574 if (!Val) { 3575 if (LastEnumConst) { 3576 // Assign the last value + 1. 3577 EnumVal = LastEnumConst->getInitVal(); 3578 ++EnumVal; 3579 3580 // Check for overflow on increment. 3581 if (EnumVal < LastEnumConst->getInitVal()) 3582 Diag(IdLoc, diag::warn_enum_value_overflow); 3583 3584 EltTy = LastEnumConst->getType(); 3585 } else { 3586 // First value, set to zero. 3587 EltTy = Context.IntTy; 3588 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3589 } 3590 } 3591 3592 EnumConstantDecl *New = 3593 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3594 Val, EnumVal); 3595 3596 // Register this decl in the current scope stack. 3597 PushOnScopeChains(New, S); 3598 3599 return New; 3600} 3601 3602// FIXME: For consistency with ActOnFields(), we should have the parser 3603// pass in the source location for the left/right braces. 3604void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3605 DeclTy **Elements, unsigned NumElements) { 3606 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3607 QualType EnumType = Context.getTypeDeclType(Enum); 3608 3609 // TODO: If the result value doesn't fit in an int, it must be a long or long 3610 // long value. ISO C does not support this, but GCC does as an extension, 3611 // emit a warning. 3612 unsigned IntWidth = Context.Target.getIntWidth(); 3613 3614 // Verify that all the values are okay, compute the size of the values, and 3615 // reverse the list. 3616 unsigned NumNegativeBits = 0; 3617 unsigned NumPositiveBits = 0; 3618 3619 // Keep track of whether all elements have type int. 3620 bool AllElementsInt = true; 3621 3622 for (unsigned i = 0; i != NumElements; ++i) { 3623 EnumConstantDecl *ECD = 3624 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3625 if (!ECD) continue; // Already issued a diagnostic. 3626 3627 // If the enum value doesn't fit in an int, emit an extension warning. 3628 const llvm::APSInt &InitVal = ECD->getInitVal(); 3629 assert(InitVal.getBitWidth() >= IntWidth && 3630 "Should have promoted value to int"); 3631 if (InitVal.getBitWidth() > IntWidth) { 3632 llvm::APSInt V(InitVal); 3633 V.trunc(IntWidth); 3634 V.extend(InitVal.getBitWidth()); 3635 if (V != InitVal) 3636 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3637 << InitVal.toString(10); 3638 } 3639 3640 // Keep track of the size of positive and negative values. 3641 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3642 NumPositiveBits = std::max(NumPositiveBits, 3643 (unsigned)InitVal.getActiveBits()); 3644 else 3645 NumNegativeBits = std::max(NumNegativeBits, 3646 (unsigned)InitVal.getMinSignedBits()); 3647 3648 // Keep track of whether every enum element has type int (very commmon). 3649 if (AllElementsInt) 3650 AllElementsInt = ECD->getType() == Context.IntTy; 3651 } 3652 3653 // Figure out the type that should be used for this enum. 3654 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3655 QualType BestType; 3656 unsigned BestWidth; 3657 3658 if (NumNegativeBits) { 3659 // If there is a negative value, figure out the smallest integer type (of 3660 // int/long/longlong) that fits. 3661 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3662 BestType = Context.IntTy; 3663 BestWidth = IntWidth; 3664 } else { 3665 BestWidth = Context.Target.getLongWidth(); 3666 3667 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3668 BestType = Context.LongTy; 3669 else { 3670 BestWidth = Context.Target.getLongLongWidth(); 3671 3672 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3673 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3674 BestType = Context.LongLongTy; 3675 } 3676 } 3677 } else { 3678 // If there is no negative value, figure out which of uint, ulong, ulonglong 3679 // fits. 3680 if (NumPositiveBits <= IntWidth) { 3681 BestType = Context.UnsignedIntTy; 3682 BestWidth = IntWidth; 3683 } else if (NumPositiveBits <= 3684 (BestWidth = Context.Target.getLongWidth())) { 3685 BestType = Context.UnsignedLongTy; 3686 } else { 3687 BestWidth = Context.Target.getLongLongWidth(); 3688 assert(NumPositiveBits <= BestWidth && 3689 "How could an initializer get larger than ULL?"); 3690 BestType = Context.UnsignedLongLongTy; 3691 } 3692 } 3693 3694 // Loop over all of the enumerator constants, changing their types to match 3695 // the type of the enum if needed. 3696 for (unsigned i = 0; i != NumElements; ++i) { 3697 EnumConstantDecl *ECD = 3698 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3699 if (!ECD) continue; // Already issued a diagnostic. 3700 3701 // Standard C says the enumerators have int type, but we allow, as an 3702 // extension, the enumerators to be larger than int size. If each 3703 // enumerator value fits in an int, type it as an int, otherwise type it the 3704 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3705 // that X has type 'int', not 'unsigned'. 3706 if (ECD->getType() == Context.IntTy) { 3707 // Make sure the init value is signed. 3708 llvm::APSInt IV = ECD->getInitVal(); 3709 IV.setIsSigned(true); 3710 ECD->setInitVal(IV); 3711 3712 if (getLangOptions().CPlusPlus) 3713 // C++ [dcl.enum]p4: Following the closing brace of an 3714 // enum-specifier, each enumerator has the type of its 3715 // enumeration. 3716 ECD->setType(EnumType); 3717 continue; // Already int type. 3718 } 3719 3720 // Determine whether the value fits into an int. 3721 llvm::APSInt InitVal = ECD->getInitVal(); 3722 bool FitsInInt; 3723 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3724 FitsInInt = InitVal.getActiveBits() < IntWidth; 3725 else 3726 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3727 3728 // If it fits into an integer type, force it. Otherwise force it to match 3729 // the enum decl type. 3730 QualType NewTy; 3731 unsigned NewWidth; 3732 bool NewSign; 3733 if (FitsInInt) { 3734 NewTy = Context.IntTy; 3735 NewWidth = IntWidth; 3736 NewSign = true; 3737 } else if (ECD->getType() == BestType) { 3738 // Already the right type! 3739 if (getLangOptions().CPlusPlus) 3740 // C++ [dcl.enum]p4: Following the closing brace of an 3741 // enum-specifier, each enumerator has the type of its 3742 // enumeration. 3743 ECD->setType(EnumType); 3744 continue; 3745 } else { 3746 NewTy = BestType; 3747 NewWidth = BestWidth; 3748 NewSign = BestType->isSignedIntegerType(); 3749 } 3750 3751 // Adjust the APSInt value. 3752 InitVal.extOrTrunc(NewWidth); 3753 InitVal.setIsSigned(NewSign); 3754 ECD->setInitVal(InitVal); 3755 3756 // Adjust the Expr initializer and type. 3757 if (ECD->getInitExpr()) 3758 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3759 /*isLvalue=*/false)); 3760 if (getLangOptions().CPlusPlus) 3761 // C++ [dcl.enum]p4: Following the closing brace of an 3762 // enum-specifier, each enumerator has the type of its 3763 // enumeration. 3764 ECD->setType(EnumType); 3765 else 3766 ECD->setType(NewTy); 3767 } 3768 3769 Enum->completeDefinition(Context, BestType); 3770} 3771 3772Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3773 ExprArg expr) { 3774 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3775 3776 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3777} 3778 3779 3780void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3781 ExprTy *alignment, SourceLocation PragmaLoc, 3782 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3783 Expr *Alignment = static_cast<Expr *>(alignment); 3784 3785 // If specified then alignment must be a "small" power of two. 3786 unsigned AlignmentVal = 0; 3787 if (Alignment) { 3788 llvm::APSInt Val; 3789 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3790 !Val.isPowerOf2() || 3791 Val.getZExtValue() > 16) { 3792 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3793 delete Alignment; 3794 return; // Ignore 3795 } 3796 3797 AlignmentVal = (unsigned) Val.getZExtValue(); 3798 } 3799 3800 switch (Kind) { 3801 case Action::PPK_Default: // pack([n]) 3802 PackContext.setAlignment(AlignmentVal); 3803 break; 3804 3805 case Action::PPK_Show: // pack(show) 3806 // Show the current alignment, making sure to show the right value 3807 // for the default. 3808 AlignmentVal = PackContext.getAlignment(); 3809 // FIXME: This should come from the target. 3810 if (AlignmentVal == 0) 3811 AlignmentVal = 8; 3812 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3813 break; 3814 3815 case Action::PPK_Push: // pack(push [, id] [, [n]) 3816 PackContext.push(Name); 3817 // Set the new alignment if specified. 3818 if (Alignment) 3819 PackContext.setAlignment(AlignmentVal); 3820 break; 3821 3822 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3823 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3824 // "#pragma pack(pop, identifier, n) is undefined" 3825 if (Alignment && Name) 3826 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3827 3828 // Do the pop. 3829 if (!PackContext.pop(Name)) { 3830 // If a name was specified then failure indicates the name 3831 // wasn't found. Otherwise failure indicates the stack was 3832 // empty. 3833 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3834 << (Name ? "no record matching name" : "stack empty"); 3835 3836 // FIXME: Warn about popping named records as MSVC does. 3837 } else { 3838 // Pop succeeded, set the new alignment if specified. 3839 if (Alignment) 3840 PackContext.setAlignment(AlignmentVal); 3841 } 3842 break; 3843 3844 default: 3845 assert(0 && "Invalid #pragma pack kind."); 3846 } 3847} 3848 3849bool PragmaPackStack::pop(IdentifierInfo *Name) { 3850 if (Stack.empty()) 3851 return false; 3852 3853 // If name is empty just pop top. 3854 if (!Name) { 3855 Alignment = Stack.back().first; 3856 Stack.pop_back(); 3857 return true; 3858 } 3859 3860 // Otherwise, find the named record. 3861 for (unsigned i = Stack.size(); i != 0; ) { 3862 --i; 3863 if (Stack[i].second == Name) { 3864 // Found it, pop up to and including this record. 3865 Alignment = Stack[i].first; 3866 Stack.erase(Stack.begin() + i, Stack.end()); 3867 return true; 3868 } 3869 } 3870 3871 return false; 3872} 3873