SemaDecl.cpp revision be109b3e768b70f9efb106d25d6b5a2c72c5a9b8
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/ExprCXX.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Basic/Diagnostic.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 34Sema::TypeTy *Sema::isTypeName(IdentifierInfo &II, Scope *S, 35 const CXXScopeSpec *SS) { 36 DeclContext *DC = 0; 37 if (SS) { 38 if (SS->isInvalid()) 39 return 0; 40 DC = static_cast<DeclContext*>(SS->getScopeRep()); 41 } 42 LookupResult Result = LookupDecl(&II, Decl::IDNS_Ordinary, S, DC, false); 43 44 Decl *IIDecl = 0; 45 switch (Result.getKind()) { 46 case LookupResult::NotFound: 47 case LookupResult::FoundOverloaded: 48 case LookupResult::AmbiguousBaseSubobjectTypes: 49 case LookupResult::AmbiguousBaseSubobjects: 50 // FIXME: In the event of an ambiguous lookup, we could visit all of 51 // the entities found to determine whether they are all types. This 52 // might provide better diagnostics. 53 return 0; 54 55 case LookupResult::Found: 56 IIDecl = Result.getAsDecl(); 57 break; 58 } 59 60 if (isa<TypedefDecl>(IIDecl) || 61 isa<ObjCInterfaceDecl>(IIDecl) || 62 isa<TagDecl>(IIDecl) || 63 isa<TemplateTypeParmDecl>(IIDecl)) 64 return IIDecl; 65 return 0; 66} 67 68DeclContext *Sema::getContainingDC(DeclContext *DC) { 69 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 70 // A C++ out-of-line method will return to the file declaration context. 71 if (MD->isOutOfLineDefinition()) 72 return MD->getLexicalDeclContext(); 73 74 // A C++ inline method is parsed *after* the topmost class it was declared in 75 // is fully parsed (it's "complete"). 76 // The parsing of a C++ inline method happens at the declaration context of 77 // the topmost (non-nested) class it is lexically declared in. 78 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 79 DC = MD->getParent(); 80 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 81 DC = RD; 82 83 // Return the declaration context of the topmost class the inline method is 84 // declared in. 85 return DC; 86 } 87 88 if (isa<ObjCMethodDecl>(DC)) 89 return Context.getTranslationUnitDecl(); 90 91 if (Decl *D = dyn_cast<Decl>(DC)) 92 return D->getLexicalDeclContext(); 93 94 return DC->getLexicalParent(); 95} 96 97void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 98 assert(getContainingDC(DC) == CurContext && 99 "The next DeclContext should be lexically contained in the current one."); 100 CurContext = DC; 101 S->setEntity(DC); 102} 103 104void Sema::PopDeclContext() { 105 assert(CurContext && "DeclContext imbalance!"); 106 107 CurContext = getContainingDC(CurContext); 108} 109 110/// Add this decl to the scope shadowed decl chains. 111void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 112 // Move up the scope chain until we find the nearest enclosing 113 // non-transparent context. The declaration will be introduced into this 114 // scope. 115 while (S->getEntity() && 116 ((DeclContext *)S->getEntity())->isTransparentContext()) 117 S = S->getParent(); 118 119 S->AddDecl(D); 120 121 // Add scoped declarations into their context, so that they can be 122 // found later. Declarations without a context won't be inserted 123 // into any context. 124 CurContext->addDecl(D); 125 126 // C++ [basic.scope]p4: 127 // -- exactly one declaration shall declare a class name or 128 // enumeration name that is not a typedef name and the other 129 // declarations shall all refer to the same object or 130 // enumerator, or all refer to functions and function templates; 131 // in this case the class name or enumeration name is hidden. 132 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 133 // We are pushing the name of a tag (enum or class). 134 if (CurContext->getLookupContext() 135 == TD->getDeclContext()->getLookupContext()) { 136 // We're pushing the tag into the current context, which might 137 // require some reshuffling in the identifier resolver. 138 IdentifierResolver::iterator 139 I = IdResolver.begin(TD->getDeclName(), CurContext, 140 false/*LookInParentCtx*/), 141 IEnd = IdResolver.end(); 142 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 143 NamedDecl *PrevDecl = *I; 144 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 145 PrevDecl = *I, ++I) { 146 if (TD->declarationReplaces(*I)) { 147 // This is a redeclaration. Remove it from the chain and 148 // break out, so that we'll add in the shadowed 149 // declaration. 150 S->RemoveDecl(*I); 151 if (PrevDecl == *I) { 152 IdResolver.RemoveDecl(*I); 153 IdResolver.AddDecl(TD); 154 return; 155 } else { 156 IdResolver.RemoveDecl(*I); 157 break; 158 } 159 } 160 } 161 162 // There is already a declaration with the same name in the same 163 // scope, which is not a tag declaration. It must be found 164 // before we find the new declaration, so insert the new 165 // declaration at the end of the chain. 166 IdResolver.AddShadowedDecl(TD, PrevDecl); 167 168 return; 169 } 170 } 171 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 172 // We are pushing the name of a function, which might be an 173 // overloaded name. 174 FunctionDecl *FD = cast<FunctionDecl>(D); 175 DeclContext *DC = FD->getDeclContext()->getLookupContext(); 176 IdentifierResolver::iterator Redecl 177 = std::find_if(IdResolver.begin(FD->getDeclName(), DC, 178 false/*LookInParentCtx*/), 179 IdResolver.end(), 180 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 181 FD)); 182 if (Redecl != IdResolver.end()) { 183 // There is already a declaration of a function on our 184 // IdResolver chain. Replace it with this declaration. 185 S->RemoveDecl(*Redecl); 186 IdResolver.RemoveDecl(*Redecl); 187 } 188 } 189 190 IdResolver.AddDecl(D); 191} 192 193void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 194 if (S->decl_empty()) return; 195 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 196 "Scope shouldn't contain decls!"); 197 198 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 199 I != E; ++I) { 200 Decl *TmpD = static_cast<Decl*>(*I); 201 assert(TmpD && "This decl didn't get pushed??"); 202 203 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 204 NamedDecl *D = cast<NamedDecl>(TmpD); 205 206 if (!D->getDeclName()) continue; 207 208 // Remove this name from our lexical scope. 209 IdResolver.RemoveDecl(D); 210 } 211} 212 213/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 214/// return 0 if one not found. 215ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 216 // The third "scope" argument is 0 since we aren't enabling lazy built-in 217 // creation from this context. 218 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 219 220 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 221} 222 223/// getNonFieldDeclScope - Retrieves the innermost scope, starting 224/// from S, where a non-field would be declared. This routine copes 225/// with the difference between C and C++ scoping rules in structs and 226/// unions. For example, the following code is well-formed in C but 227/// ill-formed in C++: 228/// @code 229/// struct S6 { 230/// enum { BAR } e; 231/// }; 232/// 233/// void test_S6() { 234/// struct S6 a; 235/// a.e = BAR; 236/// } 237/// @endcode 238/// For the declaration of BAR, this routine will return a different 239/// scope. The scope S will be the scope of the unnamed enumeration 240/// within S6. In C++, this routine will return the scope associated 241/// with S6, because the enumeration's scope is a transparent 242/// context but structures can contain non-field names. In C, this 243/// routine will return the translation unit scope, since the 244/// enumeration's scope is a transparent context and structures cannot 245/// contain non-field names. 246Scope *Sema::getNonFieldDeclScope(Scope *S) { 247 while (((S->getFlags() & Scope::DeclScope) == 0) || 248 (S->getEntity() && 249 ((DeclContext *)S->getEntity())->isTransparentContext()) || 250 (S->isClassScope() && !getLangOptions().CPlusPlus)) 251 S = S->getParent(); 252 return S; 253} 254 255/// LookupDecl - Look up the inner-most declaration in the specified 256/// namespace. NamespaceNameOnly - during lookup only namespace names 257/// are considered as required in C++ [basic.lookup.udir] 3.4.6.p1 258/// 'When looking up a namespace-name in a using-directive or 259/// namespace-alias-definition, only namespace names are considered.' 260/// 261/// Note: The use of this routine is deprecated. Please use 262/// LookupName, LookupQualifiedName, or LookupParsedName instead. 263Sema::LookupResult 264Sema::LookupDecl(DeclarationName Name, unsigned NSI, Scope *S, 265 const DeclContext *LookupCtx, 266 bool enableLazyBuiltinCreation, 267 bool LookInParent, 268 bool NamespaceNameOnly) { 269 LookupCriteria::NameKind Kind; 270 if (NSI == Decl::IDNS_Ordinary) { 271 if (NamespaceNameOnly) 272 Kind = LookupCriteria::Namespace; 273 else 274 Kind = LookupCriteria::Ordinary; 275 } else if (NSI == Decl::IDNS_Tag) 276 Kind = LookupCriteria::Tag; 277 else { 278 assert(NSI == Decl::IDNS_Member &&"Unable to grok LookupDecl NSI argument"); 279 Kind = LookupCriteria::Member; 280 } 281 282 if (LookupCtx) 283 return LookupQualifiedName(const_cast<DeclContext *>(LookupCtx), Name, 284 LookupCriteria(Kind, !LookInParent, 285 getLangOptions().CPlusPlus)); 286 287 // Unqualified lookup 288 return LookupName(S, Name, 289 LookupCriteria(Kind, !LookInParent, 290 getLangOptions().CPlusPlus)); 291} 292 293void Sema::InitBuiltinVaListType() { 294 if (!Context.getBuiltinVaListType().isNull()) 295 return; 296 297 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 298 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 299 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 300 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 301} 302 303/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 304/// lazily create a decl for it. 305NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 306 Scope *S) { 307 Builtin::ID BID = (Builtin::ID)bid; 308 309 if (Context.BuiltinInfo.hasVAListUse(BID)) 310 InitBuiltinVaListType(); 311 312 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 313 FunctionDecl *New = FunctionDecl::Create(Context, 314 Context.getTranslationUnitDecl(), 315 SourceLocation(), II, R, 316 FunctionDecl::Extern, false); 317 318 // Create Decl objects for each parameter, adding them to the 319 // FunctionDecl. 320 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 321 llvm::SmallVector<ParmVarDecl*, 16> Params; 322 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 323 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 324 FT->getArgType(i), VarDecl::None, 0)); 325 New->setParams(Context, &Params[0], Params.size()); 326 } 327 328 329 330 // TUScope is the translation-unit scope to insert this function into. 331 // FIXME: This is hideous. We need to teach PushOnScopeChains to 332 // relate Scopes to DeclContexts, and probably eliminate CurContext 333 // entirely, but we're not there yet. 334 DeclContext *SavedContext = CurContext; 335 CurContext = Context.getTranslationUnitDecl(); 336 PushOnScopeChains(New, TUScope); 337 CurContext = SavedContext; 338 return New; 339} 340 341/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 342/// everything from the standard library is defined. 343NamespaceDecl *Sema::GetStdNamespace() { 344 if (!StdNamespace) { 345 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 346 DeclContext *Global = Context.getTranslationUnitDecl(); 347 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Ordinary, 348 0, Global, /*enableLazyBuiltinCreation=*/false); 349 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 350 } 351 return StdNamespace; 352} 353 354/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 355/// and scope as a previous declaration 'Old'. Figure out how to resolve this 356/// situation, merging decls or emitting diagnostics as appropriate. 357/// 358TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 359 bool objc_types = false; 360 // Allow multiple definitions for ObjC built-in typedefs. 361 // FIXME: Verify the underlying types are equivalent! 362 if (getLangOptions().ObjC1) { 363 const IdentifierInfo *TypeID = New->getIdentifier(); 364 switch (TypeID->getLength()) { 365 default: break; 366 case 2: 367 if (!TypeID->isStr("id")) 368 break; 369 Context.setObjCIdType(New); 370 objc_types = true; 371 break; 372 case 5: 373 if (!TypeID->isStr("Class")) 374 break; 375 Context.setObjCClassType(New); 376 objc_types = true; 377 return New; 378 case 3: 379 if (!TypeID->isStr("SEL")) 380 break; 381 Context.setObjCSelType(New); 382 objc_types = true; 383 return New; 384 case 8: 385 if (!TypeID->isStr("Protocol")) 386 break; 387 Context.setObjCProtoType(New->getUnderlyingType()); 388 objc_types = true; 389 return New; 390 } 391 // Fall through - the typedef name was not a builtin type. 392 } 393 // Verify the old decl was also a typedef. 394 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 395 if (!Old) { 396 Diag(New->getLocation(), diag::err_redefinition_different_kind) 397 << New->getDeclName(); 398 if (!objc_types) 399 Diag(OldD->getLocation(), diag::note_previous_definition); 400 return New; 401 } 402 403 // If the typedef types are not identical, reject them in all languages and 404 // with any extensions enabled. 405 if (Old->getUnderlyingType() != New->getUnderlyingType() && 406 Context.getCanonicalType(Old->getUnderlyingType()) != 407 Context.getCanonicalType(New->getUnderlyingType())) { 408 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 409 << New->getUnderlyingType() << Old->getUnderlyingType(); 410 if (!objc_types) 411 Diag(Old->getLocation(), diag::note_previous_definition); 412 return New; 413 } 414 if (objc_types) return New; 415 if (getLangOptions().Microsoft) return New; 416 417 // C++ [dcl.typedef]p2: 418 // In a given non-class scope, a typedef specifier can be used to 419 // redefine the name of any type declared in that scope to refer 420 // to the type to which it already refers. 421 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 422 return New; 423 424 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 425 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 426 // *either* declaration is in a system header. The code below implements 427 // this adhoc compatibility rule. FIXME: The following code will not 428 // work properly when compiling ".i" files (containing preprocessed output). 429 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 430 SourceManager &SrcMgr = Context.getSourceManager(); 431 if (SrcMgr.isInSystemHeader(Old->getLocation())) 432 return New; 433 if (SrcMgr.isInSystemHeader(New->getLocation())) 434 return New; 435 } 436 437 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 438 Diag(Old->getLocation(), diag::note_previous_definition); 439 return New; 440} 441 442/// DeclhasAttr - returns true if decl Declaration already has the target 443/// attribute. 444static bool DeclHasAttr(const Decl *decl, const Attr *target) { 445 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 446 if (attr->getKind() == target->getKind()) 447 return true; 448 449 return false; 450} 451 452/// MergeAttributes - append attributes from the Old decl to the New one. 453static void MergeAttributes(Decl *New, Decl *Old) { 454 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 455 456 while (attr) { 457 tmp = attr; 458 attr = attr->getNext(); 459 460 if (!DeclHasAttr(New, tmp)) { 461 tmp->setInherited(true); 462 New->addAttr(tmp); 463 } else { 464 tmp->setNext(0); 465 delete(tmp); 466 } 467 } 468 469 Old->invalidateAttrs(); 470} 471 472/// MergeFunctionDecl - We just parsed a function 'New' from 473/// declarator D which has the same name and scope as a previous 474/// declaration 'Old'. Figure out how to resolve this situation, 475/// merging decls or emitting diagnostics as appropriate. 476/// Redeclaration will be set true if this New is a redeclaration OldD. 477/// 478/// In C++, New and Old must be declarations that are not 479/// overloaded. Use IsOverload to determine whether New and Old are 480/// overloaded, and to select the Old declaration that New should be 481/// merged with. 482FunctionDecl * 483Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 484 assert(!isa<OverloadedFunctionDecl>(OldD) && 485 "Cannot merge with an overloaded function declaration"); 486 487 Redeclaration = false; 488 // Verify the old decl was also a function. 489 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 490 if (!Old) { 491 Diag(New->getLocation(), diag::err_redefinition_different_kind) 492 << New->getDeclName(); 493 Diag(OldD->getLocation(), diag::note_previous_definition); 494 return New; 495 } 496 497 // Determine whether the previous declaration was a definition, 498 // implicit declaration, or a declaration. 499 diag::kind PrevDiag; 500 if (Old->isThisDeclarationADefinition()) 501 PrevDiag = diag::note_previous_definition; 502 else if (Old->isImplicit()) 503 PrevDiag = diag::note_previous_implicit_declaration; 504 else 505 PrevDiag = diag::note_previous_declaration; 506 507 QualType OldQType = Context.getCanonicalType(Old->getType()); 508 QualType NewQType = Context.getCanonicalType(New->getType()); 509 510 if (getLangOptions().CPlusPlus) { 511 // (C++98 13.1p2): 512 // Certain function declarations cannot be overloaded: 513 // -- Function declarations that differ only in the return type 514 // cannot be overloaded. 515 QualType OldReturnType 516 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 517 QualType NewReturnType 518 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 519 if (OldReturnType != NewReturnType) { 520 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 521 Diag(Old->getLocation(), PrevDiag); 522 Redeclaration = true; 523 return New; 524 } 525 526 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 527 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 528 if (OldMethod && NewMethod) { 529 // -- Member function declarations with the same name and the 530 // same parameter types cannot be overloaded if any of them 531 // is a static member function declaration. 532 if (OldMethod->isStatic() || NewMethod->isStatic()) { 533 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 534 Diag(Old->getLocation(), PrevDiag); 535 return New; 536 } 537 538 // C++ [class.mem]p1: 539 // [...] A member shall not be declared twice in the 540 // member-specification, except that a nested class or member 541 // class template can be declared and then later defined. 542 if (OldMethod->getLexicalDeclContext() == 543 NewMethod->getLexicalDeclContext()) { 544 unsigned NewDiag; 545 if (isa<CXXConstructorDecl>(OldMethod)) 546 NewDiag = diag::err_constructor_redeclared; 547 else if (isa<CXXDestructorDecl>(NewMethod)) 548 NewDiag = diag::err_destructor_redeclared; 549 else if (isa<CXXConversionDecl>(NewMethod)) 550 NewDiag = diag::err_conv_function_redeclared; 551 else 552 NewDiag = diag::err_member_redeclared; 553 554 Diag(New->getLocation(), NewDiag); 555 Diag(Old->getLocation(), PrevDiag); 556 } 557 } 558 559 // (C++98 8.3.5p3): 560 // All declarations for a function shall agree exactly in both the 561 // return type and the parameter-type-list. 562 if (OldQType == NewQType) { 563 // We have a redeclaration. 564 MergeAttributes(New, Old); 565 Redeclaration = true; 566 return MergeCXXFunctionDecl(New, Old); 567 } 568 569 // Fall through for conflicting redeclarations and redefinitions. 570 } 571 572 // C: Function types need to be compatible, not identical. This handles 573 // duplicate function decls like "void f(int); void f(enum X);" properly. 574 if (!getLangOptions().CPlusPlus && 575 Context.typesAreCompatible(OldQType, NewQType)) { 576 MergeAttributes(New, Old); 577 Redeclaration = true; 578 return New; 579 } 580 581 // A function that has already been declared has been redeclared or defined 582 // with a different type- show appropriate diagnostic 583 584 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 585 // TODO: This is totally simplistic. It should handle merging functions 586 // together etc, merging extern int X; int X; ... 587 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 588 Diag(Old->getLocation(), PrevDiag); 589 return New; 590} 591 592/// Predicate for C "tentative" external object definitions (C99 6.9.2). 593static bool isTentativeDefinition(VarDecl *VD) { 594 if (VD->isFileVarDecl()) 595 return (!VD->getInit() && 596 (VD->getStorageClass() == VarDecl::None || 597 VD->getStorageClass() == VarDecl::Static)); 598 return false; 599} 600 601/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 602/// when dealing with C "tentative" external object definitions (C99 6.9.2). 603void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 604 bool VDIsTentative = isTentativeDefinition(VD); 605 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 606 607 // FIXME: I don't think this will actually see all of the 608 // redefinitions. Can't we check this property on-the-fly? 609 for (IdentifierResolver::iterator 610 I = IdResolver.begin(VD->getIdentifier(), 611 VD->getDeclContext(), false/*LookInParentCtx*/), 612 E = IdResolver.end(); I != E; ++I) { 613 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 614 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 615 616 // Handle the following case: 617 // int a[10]; 618 // int a[]; - the code below makes sure we set the correct type. 619 // int a[11]; - this is an error, size isn't 10. 620 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 621 OldDecl->getType()->isConstantArrayType()) 622 VD->setType(OldDecl->getType()); 623 624 // Check for "tentative" definitions. We can't accomplish this in 625 // MergeVarDecl since the initializer hasn't been attached. 626 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 627 continue; 628 629 // Handle __private_extern__ just like extern. 630 if (OldDecl->getStorageClass() != VarDecl::Extern && 631 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 632 VD->getStorageClass() != VarDecl::Extern && 633 VD->getStorageClass() != VarDecl::PrivateExtern) { 634 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 635 Diag(OldDecl->getLocation(), diag::note_previous_definition); 636 } 637 } 638 } 639} 640 641/// MergeVarDecl - We just parsed a variable 'New' which has the same name 642/// and scope as a previous declaration 'Old'. Figure out how to resolve this 643/// situation, merging decls or emitting diagnostics as appropriate. 644/// 645/// Tentative definition rules (C99 6.9.2p2) are checked by 646/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 647/// definitions here, since the initializer hasn't been attached. 648/// 649VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 650 // Verify the old decl was also a variable. 651 VarDecl *Old = dyn_cast<VarDecl>(OldD); 652 if (!Old) { 653 Diag(New->getLocation(), diag::err_redefinition_different_kind) 654 << New->getDeclName(); 655 Diag(OldD->getLocation(), diag::note_previous_definition); 656 return New; 657 } 658 659 MergeAttributes(New, Old); 660 661 // Verify the types match. 662 QualType OldCType = Context.getCanonicalType(Old->getType()); 663 QualType NewCType = Context.getCanonicalType(New->getType()); 664 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 665 Diag(New->getLocation(), diag::err_redefinition_different_type) 666 << New->getDeclName(); 667 Diag(Old->getLocation(), diag::note_previous_definition); 668 return New; 669 } 670 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 671 if (New->getStorageClass() == VarDecl::Static && 672 (Old->getStorageClass() == VarDecl::None || 673 Old->getStorageClass() == VarDecl::Extern)) { 674 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 675 Diag(Old->getLocation(), diag::note_previous_definition); 676 return New; 677 } 678 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 679 if (New->getStorageClass() != VarDecl::Static && 680 Old->getStorageClass() == VarDecl::Static) { 681 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 682 Diag(Old->getLocation(), diag::note_previous_definition); 683 return New; 684 } 685 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 686 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 687 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 688 Diag(Old->getLocation(), diag::note_previous_definition); 689 } 690 return New; 691} 692 693/// CheckParmsForFunctionDef - Check that the parameters of the given 694/// function are appropriate for the definition of a function. This 695/// takes care of any checks that cannot be performed on the 696/// declaration itself, e.g., that the types of each of the function 697/// parameters are complete. 698bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 699 bool HasInvalidParm = false; 700 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 701 ParmVarDecl *Param = FD->getParamDecl(p); 702 703 // C99 6.7.5.3p4: the parameters in a parameter type list in a 704 // function declarator that is part of a function definition of 705 // that function shall not have incomplete type. 706 if (!Param->isInvalidDecl() && 707 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 708 diag::err_typecheck_decl_incomplete_type)) { 709 Param->setInvalidDecl(); 710 HasInvalidParm = true; 711 } 712 713 // C99 6.9.1p5: If the declarator includes a parameter type list, the 714 // declaration of each parameter shall include an identifier. 715 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 716 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 717 } 718 719 return HasInvalidParm; 720} 721 722/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 723/// no declarator (e.g. "struct foo;") is parsed. 724Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 725 TagDecl *Tag 726 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 727 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 728 if (!Record->getDeclName() && Record->isDefinition() && 729 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 730 return BuildAnonymousStructOrUnion(S, DS, Record); 731 732 // Microsoft allows unnamed struct/union fields. Don't complain 733 // about them. 734 // FIXME: Should we support Microsoft's extensions in this area? 735 if (Record->getDeclName() && getLangOptions().Microsoft) 736 return Tag; 737 } 738 739 if (!DS.isMissingDeclaratorOk()) { 740 // Warn about typedefs of enums without names, since this is an 741 // extension in both Microsoft an GNU. 742 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 743 Tag && isa<EnumDecl>(Tag)) { 744 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 745 << DS.getSourceRange(); 746 return Tag; 747 } 748 749 // FIXME: This diagnostic is emitted even when various previous 750 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 751 // DeclSpec has no means of communicating this information, and the 752 // responsible parser functions are quite far apart. 753 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 754 << DS.getSourceRange(); 755 return 0; 756 } 757 758 return Tag; 759} 760 761/// InjectAnonymousStructOrUnionMembers - Inject the members of the 762/// anonymous struct or union AnonRecord into the owning context Owner 763/// and scope S. This routine will be invoked just after we realize 764/// that an unnamed union or struct is actually an anonymous union or 765/// struct, e.g., 766/// 767/// @code 768/// union { 769/// int i; 770/// float f; 771/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 772/// // f into the surrounding scope.x 773/// @endcode 774/// 775/// This routine is recursive, injecting the names of nested anonymous 776/// structs/unions into the owning context and scope as well. 777bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 778 RecordDecl *AnonRecord) { 779 bool Invalid = false; 780 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 781 FEnd = AnonRecord->field_end(); 782 F != FEnd; ++F) { 783 if ((*F)->getDeclName()) { 784 Decl *PrevDecl = LookupDecl((*F)->getDeclName(), Decl::IDNS_Ordinary, 785 S, Owner, false, false, false); 786 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 787 // C++ [class.union]p2: 788 // The names of the members of an anonymous union shall be 789 // distinct from the names of any other entity in the 790 // scope in which the anonymous union is declared. 791 unsigned diagKind 792 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 793 : diag::err_anonymous_struct_member_redecl; 794 Diag((*F)->getLocation(), diagKind) 795 << (*F)->getDeclName(); 796 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 797 Invalid = true; 798 } else { 799 // C++ [class.union]p2: 800 // For the purpose of name lookup, after the anonymous union 801 // definition, the members of the anonymous union are 802 // considered to have been defined in the scope in which the 803 // anonymous union is declared. 804 Owner->makeDeclVisibleInContext(*F); 805 S->AddDecl(*F); 806 IdResolver.AddDecl(*F); 807 } 808 } else if (const RecordType *InnerRecordType 809 = (*F)->getType()->getAsRecordType()) { 810 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 811 if (InnerRecord->isAnonymousStructOrUnion()) 812 Invalid = Invalid || 813 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 814 } 815 } 816 817 return Invalid; 818} 819 820/// ActOnAnonymousStructOrUnion - Handle the declaration of an 821/// anonymous structure or union. Anonymous unions are a C++ feature 822/// (C++ [class.union]) and a GNU C extension; anonymous structures 823/// are a GNU C and GNU C++ extension. 824Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 825 RecordDecl *Record) { 826 DeclContext *Owner = Record->getDeclContext(); 827 828 // Diagnose whether this anonymous struct/union is an extension. 829 if (Record->isUnion() && !getLangOptions().CPlusPlus) 830 Diag(Record->getLocation(), diag::ext_anonymous_union); 831 else if (!Record->isUnion()) 832 Diag(Record->getLocation(), diag::ext_anonymous_struct); 833 834 // C and C++ require different kinds of checks for anonymous 835 // structs/unions. 836 bool Invalid = false; 837 if (getLangOptions().CPlusPlus) { 838 const char* PrevSpec = 0; 839 // C++ [class.union]p3: 840 // Anonymous unions declared in a named namespace or in the 841 // global namespace shall be declared static. 842 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 843 (isa<TranslationUnitDecl>(Owner) || 844 (isa<NamespaceDecl>(Owner) && 845 cast<NamespaceDecl>(Owner)->getDeclName()))) { 846 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 847 Invalid = true; 848 849 // Recover by adding 'static'. 850 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 851 } 852 // C++ [class.union]p3: 853 // A storage class is not allowed in a declaration of an 854 // anonymous union in a class scope. 855 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 856 isa<RecordDecl>(Owner)) { 857 Diag(DS.getStorageClassSpecLoc(), 858 diag::err_anonymous_union_with_storage_spec); 859 Invalid = true; 860 861 // Recover by removing the storage specifier. 862 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 863 PrevSpec); 864 } 865 866 // C++ [class.union]p2: 867 // The member-specification of an anonymous union shall only 868 // define non-static data members. [Note: nested types and 869 // functions cannot be declared within an anonymous union. ] 870 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 871 MemEnd = Record->decls_end(); 872 Mem != MemEnd; ++Mem) { 873 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 874 // C++ [class.union]p3: 875 // An anonymous union shall not have private or protected 876 // members (clause 11). 877 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 878 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 879 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 880 Invalid = true; 881 } 882 } else if ((*Mem)->isImplicit()) { 883 // Any implicit members are fine. 884 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 885 if (!MemRecord->isAnonymousStructOrUnion() && 886 MemRecord->getDeclName()) { 887 // This is a nested type declaration. 888 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 889 << (int)Record->isUnion(); 890 Invalid = true; 891 } 892 } else { 893 // We have something that isn't a non-static data 894 // member. Complain about it. 895 unsigned DK = diag::err_anonymous_record_bad_member; 896 if (isa<TypeDecl>(*Mem)) 897 DK = diag::err_anonymous_record_with_type; 898 else if (isa<FunctionDecl>(*Mem)) 899 DK = diag::err_anonymous_record_with_function; 900 else if (isa<VarDecl>(*Mem)) 901 DK = diag::err_anonymous_record_with_static; 902 Diag((*Mem)->getLocation(), DK) 903 << (int)Record->isUnion(); 904 Invalid = true; 905 } 906 } 907 } else { 908 // FIXME: Check GNU C semantics 909 if (Record->isUnion() && !Owner->isRecord()) { 910 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 911 << (int)getLangOptions().CPlusPlus; 912 Invalid = true; 913 } 914 } 915 916 if (!Record->isUnion() && !Owner->isRecord()) { 917 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 918 << (int)getLangOptions().CPlusPlus; 919 Invalid = true; 920 } 921 922 // Create a declaration for this anonymous struct/union. 923 NamedDecl *Anon = 0; 924 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 925 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 926 /*IdentifierInfo=*/0, 927 Context.getTypeDeclType(Record), 928 /*BitWidth=*/0, /*Mutable=*/false); 929 Anon->setAccess(AS_public); 930 if (getLangOptions().CPlusPlus) 931 FieldCollector->Add(cast<FieldDecl>(Anon)); 932 } else { 933 VarDecl::StorageClass SC; 934 switch (DS.getStorageClassSpec()) { 935 default: assert(0 && "Unknown storage class!"); 936 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 937 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 938 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 939 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 940 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 941 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 942 case DeclSpec::SCS_mutable: 943 // mutable can only appear on non-static class members, so it's always 944 // an error here 945 Diag(Record->getLocation(), diag::err_mutable_nonmember); 946 Invalid = true; 947 SC = VarDecl::None; 948 break; 949 } 950 951 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 952 /*IdentifierInfo=*/0, 953 Context.getTypeDeclType(Record), 954 SC, DS.getSourceRange().getBegin()); 955 } 956 Anon->setImplicit(); 957 958 // Add the anonymous struct/union object to the current 959 // context. We'll be referencing this object when we refer to one of 960 // its members. 961 Owner->addDecl(Anon); 962 963 // Inject the members of the anonymous struct/union into the owning 964 // context and into the identifier resolver chain for name lookup 965 // purposes. 966 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 967 Invalid = true; 968 969 // Mark this as an anonymous struct/union type. Note that we do not 970 // do this until after we have already checked and injected the 971 // members of this anonymous struct/union type, because otherwise 972 // the members could be injected twice: once by DeclContext when it 973 // builds its lookup table, and once by 974 // InjectAnonymousStructOrUnionMembers. 975 Record->setAnonymousStructOrUnion(true); 976 977 if (Invalid) 978 Anon->setInvalidDecl(); 979 980 return Anon; 981} 982 983bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 984 bool DirectInit) { 985 // Get the type before calling CheckSingleAssignmentConstraints(), since 986 // it can promote the expression. 987 QualType InitType = Init->getType(); 988 989 if (getLangOptions().CPlusPlus) { 990 // FIXME: I dislike this error message. A lot. 991 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 992 return Diag(Init->getSourceRange().getBegin(), 993 diag::err_typecheck_convert_incompatible) 994 << DeclType << Init->getType() << "initializing" 995 << Init->getSourceRange(); 996 997 return false; 998 } 999 1000 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1001 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1002 InitType, Init, "initializing"); 1003} 1004 1005bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1006 const ArrayType *AT = Context.getAsArrayType(DeclT); 1007 1008 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1009 // C99 6.7.8p14. We have an array of character type with unknown size 1010 // being initialized to a string literal. 1011 llvm::APSInt ConstVal(32); 1012 ConstVal = strLiteral->getByteLength() + 1; 1013 // Return a new array type (C99 6.7.8p22). 1014 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1015 ArrayType::Normal, 0); 1016 } else { 1017 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1018 // C99 6.7.8p14. We have an array of character type with known size. 1019 // FIXME: Avoid truncation for 64-bit length strings. 1020 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1021 Diag(strLiteral->getSourceRange().getBegin(), 1022 diag::warn_initializer_string_for_char_array_too_long) 1023 << strLiteral->getSourceRange(); 1024 } 1025 // Set type from "char *" to "constant array of char". 1026 strLiteral->setType(DeclT); 1027 // For now, we always return false (meaning success). 1028 return false; 1029} 1030 1031StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1032 const ArrayType *AT = Context.getAsArrayType(DeclType); 1033 if (AT && AT->getElementType()->isCharType()) { 1034 return dyn_cast<StringLiteral>(Init); 1035 } 1036 return 0; 1037} 1038 1039bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1040 SourceLocation InitLoc, 1041 DeclarationName InitEntity, 1042 bool DirectInit) { 1043 if (DeclType->isDependentType() || Init->isTypeDependent()) 1044 return false; 1045 1046 // C++ [dcl.init.ref]p1: 1047 // A variable declared to be a T&, that is "reference to type T" 1048 // (8.3.2), shall be initialized by an object, or function, of 1049 // type T or by an object that can be converted into a T. 1050 if (DeclType->isReferenceType()) 1051 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1052 1053 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1054 // of unknown size ("[]") or an object type that is not a variable array type. 1055 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1056 return Diag(InitLoc, diag::err_variable_object_no_init) 1057 << VAT->getSizeExpr()->getSourceRange(); 1058 1059 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1060 if (!InitList) { 1061 // FIXME: Handle wide strings 1062 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1063 return CheckStringLiteralInit(strLiteral, DeclType); 1064 1065 // C++ [dcl.init]p14: 1066 // -- If the destination type is a (possibly cv-qualified) class 1067 // type: 1068 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1069 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1070 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1071 1072 // -- If the initialization is direct-initialization, or if it is 1073 // copy-initialization where the cv-unqualified version of the 1074 // source type is the same class as, or a derived class of, the 1075 // class of the destination, constructors are considered. 1076 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1077 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1078 CXXConstructorDecl *Constructor 1079 = PerformInitializationByConstructor(DeclType, &Init, 1, 1080 InitLoc, Init->getSourceRange(), 1081 InitEntity, 1082 DirectInit? IK_Direct : IK_Copy); 1083 return Constructor == 0; 1084 } 1085 1086 // -- Otherwise (i.e., for the remaining copy-initialization 1087 // cases), user-defined conversion sequences that can 1088 // convert from the source type to the destination type or 1089 // (when a conversion function is used) to a derived class 1090 // thereof are enumerated as described in 13.3.1.4, and the 1091 // best one is chosen through overload resolution 1092 // (13.3). If the conversion cannot be done or is 1093 // ambiguous, the initialization is ill-formed. The 1094 // function selected is called with the initializer 1095 // expression as its argument; if the function is a 1096 // constructor, the call initializes a temporary of the 1097 // destination type. 1098 // FIXME: We're pretending to do copy elision here; return to 1099 // this when we have ASTs for such things. 1100 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1101 return false; 1102 1103 if (InitEntity) 1104 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1105 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1106 << Init->getType() << Init->getSourceRange(); 1107 else 1108 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1109 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1110 << Init->getType() << Init->getSourceRange(); 1111 } 1112 1113 // C99 6.7.8p16. 1114 if (DeclType->isArrayType()) 1115 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1116 << Init->getSourceRange(); 1117 1118 return CheckSingleInitializer(Init, DeclType, DirectInit); 1119 } else if (getLangOptions().CPlusPlus) { 1120 // C++ [dcl.init]p14: 1121 // [...] If the class is an aggregate (8.5.1), and the initializer 1122 // is a brace-enclosed list, see 8.5.1. 1123 // 1124 // Note: 8.5.1 is handled below; here, we diagnose the case where 1125 // we have an initializer list and a destination type that is not 1126 // an aggregate. 1127 // FIXME: In C++0x, this is yet another form of initialization. 1128 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 1129 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1130 if (!ClassDecl->isAggregate()) 1131 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 1132 << DeclType << Init->getSourceRange(); 1133 } 1134 } 1135 1136 InitListChecker CheckInitList(this, InitList, DeclType); 1137 return CheckInitList.HadError(); 1138} 1139 1140/// GetNameForDeclarator - Determine the full declaration name for the 1141/// given Declarator. 1142DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1143 switch (D.getKind()) { 1144 case Declarator::DK_Abstract: 1145 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1146 return DeclarationName(); 1147 1148 case Declarator::DK_Normal: 1149 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1150 return DeclarationName(D.getIdentifier()); 1151 1152 case Declarator::DK_Constructor: { 1153 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1154 Ty = Context.getCanonicalType(Ty); 1155 return Context.DeclarationNames.getCXXConstructorName(Ty); 1156 } 1157 1158 case Declarator::DK_Destructor: { 1159 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1160 Ty = Context.getCanonicalType(Ty); 1161 return Context.DeclarationNames.getCXXDestructorName(Ty); 1162 } 1163 1164 case Declarator::DK_Conversion: { 1165 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1166 Ty = Context.getCanonicalType(Ty); 1167 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1168 } 1169 1170 case Declarator::DK_Operator: 1171 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1172 return Context.DeclarationNames.getCXXOperatorName( 1173 D.getOverloadedOperator()); 1174 } 1175 1176 assert(false && "Unknown name kind"); 1177 return DeclarationName(); 1178} 1179 1180/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1181/// functions Declaration and Definition are "nearly" matching. This 1182/// heuristic is used to improve diagnostics in the case where an 1183/// out-of-line member function definition doesn't match any 1184/// declaration within the class. 1185static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1186 FunctionDecl *Declaration, 1187 FunctionDecl *Definition) { 1188 if (Declaration->param_size() != Definition->param_size()) 1189 return false; 1190 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1191 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1192 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1193 1194 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1195 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1196 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1197 return false; 1198 } 1199 1200 return true; 1201} 1202 1203Sema::DeclTy * 1204Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1205 bool IsFunctionDefinition) { 1206 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1207 DeclarationName Name = GetNameForDeclarator(D); 1208 1209 // All of these full declarators require an identifier. If it doesn't have 1210 // one, the ParsedFreeStandingDeclSpec action should be used. 1211 if (!Name) { 1212 if (!D.getInvalidType()) // Reject this if we think it is valid. 1213 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1214 diag::err_declarator_need_ident) 1215 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1216 return 0; 1217 } 1218 1219 // The scope passed in may not be a decl scope. Zip up the scope tree until 1220 // we find one that is. 1221 while ((S->getFlags() & Scope::DeclScope) == 0 || 1222 (S->getFlags() & Scope::TemplateParamScope) != 0) 1223 S = S->getParent(); 1224 1225 DeclContext *DC; 1226 Decl *PrevDecl; 1227 NamedDecl *New; 1228 bool InvalidDecl = false; 1229 1230 // See if this is a redefinition of a variable in the same scope. 1231 if (!D.getCXXScopeSpec().isSet()) { 1232 DC = CurContext; 1233 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1234 } else { // Something like "int foo::x;" 1235 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1236 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1237 1238 // C++ 7.3.1.2p2: 1239 // Members (including explicit specializations of templates) of a named 1240 // namespace can also be defined outside that namespace by explicit 1241 // qualification of the name being defined, provided that the entity being 1242 // defined was already declared in the namespace and the definition appears 1243 // after the point of declaration in a namespace that encloses the 1244 // declarations namespace. 1245 // 1246 // Note that we only check the context at this point. We don't yet 1247 // have enough information to make sure that PrevDecl is actually 1248 // the declaration we want to match. For example, given: 1249 // 1250 // class X { 1251 // void f(); 1252 // void f(float); 1253 // }; 1254 // 1255 // void X::f(int) { } // ill-formed 1256 // 1257 // In this case, PrevDecl will point to the overload set 1258 // containing the two f's declared in X, but neither of them 1259 // matches. 1260 if (!CurContext->Encloses(DC)) { 1261 // The qualifying scope doesn't enclose the original declaration. 1262 // Emit diagnostic based on current scope. 1263 SourceLocation L = D.getIdentifierLoc(); 1264 SourceRange R = D.getCXXScopeSpec().getRange(); 1265 if (isa<FunctionDecl>(CurContext)) { 1266 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1267 } else { 1268 Diag(L, diag::err_invalid_declarator_scope) 1269 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1270 } 1271 InvalidDecl = true; 1272 } 1273 } 1274 1275 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1276 // Maybe we will complain about the shadowed template parameter. 1277 InvalidDecl = InvalidDecl 1278 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1279 // Just pretend that we didn't see the previous declaration. 1280 PrevDecl = 0; 1281 } 1282 1283 // In C++, the previous declaration we find might be a tag type 1284 // (class or enum). In this case, the new declaration will hide the 1285 // tag type. 1286 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 1287 PrevDecl = 0; 1288 1289 QualType R = GetTypeForDeclarator(D, S); 1290 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1291 1292 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1293 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1294 InvalidDecl); 1295 } else if (R.getTypePtr()->isFunctionType()) { 1296 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1297 IsFunctionDefinition, InvalidDecl); 1298 } else { 1299 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1300 InvalidDecl); 1301 } 1302 1303 if (New == 0) 1304 return 0; 1305 1306 // Set the lexical context. If the declarator has a C++ scope specifier, the 1307 // lexical context will be different from the semantic context. 1308 New->setLexicalDeclContext(CurContext); 1309 1310 // If this has an identifier, add it to the scope stack. 1311 if (Name) 1312 PushOnScopeChains(New, S); 1313 // If any semantic error occurred, mark the decl as invalid. 1314 if (D.getInvalidType() || InvalidDecl) 1315 New->setInvalidDecl(); 1316 1317 return New; 1318} 1319 1320NamedDecl* 1321Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1322 QualType R, Decl* LastDeclarator, 1323 Decl* PrevDecl, bool& InvalidDecl) { 1324 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1325 if (D.getCXXScopeSpec().isSet()) { 1326 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1327 << D.getCXXScopeSpec().getRange(); 1328 InvalidDecl = true; 1329 // Pretend we didn't see the scope specifier. 1330 DC = 0; 1331 } 1332 1333 // Check that there are no default arguments (C++ only). 1334 if (getLangOptions().CPlusPlus) 1335 CheckExtraCXXDefaultArguments(D); 1336 1337 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1338 if (!NewTD) return 0; 1339 1340 // Handle attributes prior to checking for duplicates in MergeVarDecl 1341 ProcessDeclAttributes(NewTD, D); 1342 // Merge the decl with the existing one if appropriate. If the decl is 1343 // in an outer scope, it isn't the same thing. 1344 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1345 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1346 if (NewTD == 0) return 0; 1347 } 1348 1349 if (S->getFnParent() == 0) { 1350 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1351 // then it shall have block scope. 1352 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1353 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1354 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1355 else 1356 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1357 1358 InvalidDecl = true; 1359 } 1360 } 1361 return NewTD; 1362} 1363 1364NamedDecl* 1365Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1366 QualType R, Decl* LastDeclarator, 1367 Decl* PrevDecl, bool& InvalidDecl) { 1368 DeclarationName Name = GetNameForDeclarator(D); 1369 1370 // Check that there are no default arguments (C++ only). 1371 if (getLangOptions().CPlusPlus) 1372 CheckExtraCXXDefaultArguments(D); 1373 1374 if (R.getTypePtr()->isObjCInterfaceType()) { 1375 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1376 << D.getIdentifier(); 1377 InvalidDecl = true; 1378 } 1379 1380 VarDecl *NewVD; 1381 VarDecl::StorageClass SC; 1382 switch (D.getDeclSpec().getStorageClassSpec()) { 1383 default: assert(0 && "Unknown storage class!"); 1384 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1385 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1386 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1387 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1388 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1389 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1390 case DeclSpec::SCS_mutable: 1391 // mutable can only appear on non-static class members, so it's always 1392 // an error here 1393 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1394 InvalidDecl = true; 1395 SC = VarDecl::None; 1396 break; 1397 } 1398 1399 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1400 if (!II) { 1401 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1402 << Name.getAsString(); 1403 return 0; 1404 } 1405 1406 if (DC->isRecord()) { 1407 // This is a static data member for a C++ class. 1408 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1409 D.getIdentifierLoc(), II, 1410 R); 1411 } else { 1412 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1413 if (S->getFnParent() == 0) { 1414 // C99 6.9p2: The storage-class specifiers auto and register shall not 1415 // appear in the declaration specifiers in an external declaration. 1416 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1417 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1418 InvalidDecl = true; 1419 } 1420 } 1421 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1422 II, R, SC, 1423 // FIXME: Move to DeclGroup... 1424 D.getDeclSpec().getSourceRange().getBegin()); 1425 NewVD->setThreadSpecified(ThreadSpecified); 1426 } 1427 NewVD->setNextDeclarator(LastDeclarator); 1428 1429 // Handle attributes prior to checking for duplicates in MergeVarDecl 1430 ProcessDeclAttributes(NewVD, D); 1431 1432 // Handle GNU asm-label extension (encoded as an attribute). 1433 if (Expr *E = (Expr*) D.getAsmLabel()) { 1434 // The parser guarantees this is a string. 1435 StringLiteral *SE = cast<StringLiteral>(E); 1436 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1437 SE->getByteLength()))); 1438 } 1439 1440 // Emit an error if an address space was applied to decl with local storage. 1441 // This includes arrays of objects with address space qualifiers, but not 1442 // automatic variables that point to other address spaces. 1443 // ISO/IEC TR 18037 S5.1.2 1444 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1445 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1446 InvalidDecl = true; 1447 } 1448 // Merge the decl with the existing one if appropriate. If the decl is 1449 // in an outer scope, it isn't the same thing. 1450 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1451 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1452 // The user tried to define a non-static data member 1453 // out-of-line (C++ [dcl.meaning]p1). 1454 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1455 << D.getCXXScopeSpec().getRange(); 1456 NewVD->Destroy(Context); 1457 return 0; 1458 } 1459 1460 NewVD = MergeVarDecl(NewVD, PrevDecl); 1461 if (NewVD == 0) return 0; 1462 1463 if (D.getCXXScopeSpec().isSet()) { 1464 // No previous declaration in the qualifying scope. 1465 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1466 << Name << D.getCXXScopeSpec().getRange(); 1467 InvalidDecl = true; 1468 } 1469 } 1470 return NewVD; 1471} 1472 1473NamedDecl* 1474Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1475 QualType R, Decl *LastDeclarator, 1476 Decl* PrevDecl, bool IsFunctionDefinition, 1477 bool& InvalidDecl) { 1478 assert(R.getTypePtr()->isFunctionType()); 1479 1480 DeclarationName Name = GetNameForDeclarator(D); 1481 FunctionDecl::StorageClass SC = FunctionDecl::None; 1482 switch (D.getDeclSpec().getStorageClassSpec()) { 1483 default: assert(0 && "Unknown storage class!"); 1484 case DeclSpec::SCS_auto: 1485 case DeclSpec::SCS_register: 1486 case DeclSpec::SCS_mutable: 1487 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1488 InvalidDecl = true; 1489 break; 1490 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1491 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1492 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1493 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1494 } 1495 1496 bool isInline = D.getDeclSpec().isInlineSpecified(); 1497 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1498 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1499 1500 FunctionDecl *NewFD; 1501 if (D.getKind() == Declarator::DK_Constructor) { 1502 // This is a C++ constructor declaration. 1503 assert(DC->isRecord() && 1504 "Constructors can only be declared in a member context"); 1505 1506 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1507 1508 // Create the new declaration 1509 NewFD = CXXConstructorDecl::Create(Context, 1510 cast<CXXRecordDecl>(DC), 1511 D.getIdentifierLoc(), Name, R, 1512 isExplicit, isInline, 1513 /*isImplicitlyDeclared=*/false); 1514 1515 if (InvalidDecl) 1516 NewFD->setInvalidDecl(); 1517 } else if (D.getKind() == Declarator::DK_Destructor) { 1518 // This is a C++ destructor declaration. 1519 if (DC->isRecord()) { 1520 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1521 1522 NewFD = CXXDestructorDecl::Create(Context, 1523 cast<CXXRecordDecl>(DC), 1524 D.getIdentifierLoc(), Name, R, 1525 isInline, 1526 /*isImplicitlyDeclared=*/false); 1527 1528 if (InvalidDecl) 1529 NewFD->setInvalidDecl(); 1530 } else { 1531 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1532 1533 // Create a FunctionDecl to satisfy the function definition parsing 1534 // code path. 1535 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1536 Name, R, SC, isInline, 1537 // FIXME: Move to DeclGroup... 1538 D.getDeclSpec().getSourceRange().getBegin()); 1539 InvalidDecl = true; 1540 NewFD->setInvalidDecl(); 1541 } 1542 } else if (D.getKind() == Declarator::DK_Conversion) { 1543 if (!DC->isRecord()) { 1544 Diag(D.getIdentifierLoc(), 1545 diag::err_conv_function_not_member); 1546 return 0; 1547 } else { 1548 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1549 1550 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1551 D.getIdentifierLoc(), Name, R, 1552 isInline, isExplicit); 1553 1554 if (InvalidDecl) 1555 NewFD->setInvalidDecl(); 1556 } 1557 } else if (DC->isRecord()) { 1558 // This is a C++ method declaration. 1559 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1560 D.getIdentifierLoc(), Name, R, 1561 (SC == FunctionDecl::Static), isInline); 1562 } else { 1563 NewFD = FunctionDecl::Create(Context, DC, 1564 D.getIdentifierLoc(), 1565 Name, R, SC, isInline, 1566 // FIXME: Move to DeclGroup... 1567 D.getDeclSpec().getSourceRange().getBegin()); 1568 } 1569 NewFD->setNextDeclarator(LastDeclarator); 1570 1571 // Set the lexical context. If the declarator has a C++ 1572 // scope specifier, the lexical context will be different 1573 // from the semantic context. 1574 NewFD->setLexicalDeclContext(CurContext); 1575 1576 // Handle GNU asm-label extension (encoded as an attribute). 1577 if (Expr *E = (Expr*) D.getAsmLabel()) { 1578 // The parser guarantees this is a string. 1579 StringLiteral *SE = cast<StringLiteral>(E); 1580 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1581 SE->getByteLength()))); 1582 } 1583 1584 // Copy the parameter declarations from the declarator D to 1585 // the function declaration NewFD, if they are available. 1586 if (D.getNumTypeObjects() > 0) { 1587 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1588 1589 // Create Decl objects for each parameter, adding them to the 1590 // FunctionDecl. 1591 llvm::SmallVector<ParmVarDecl*, 16> Params; 1592 1593 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1594 // function that takes no arguments, not a function that takes a 1595 // single void argument. 1596 // We let through "const void" here because Sema::GetTypeForDeclarator 1597 // already checks for that case. 1598 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1599 FTI.ArgInfo[0].Param && 1600 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1601 // empty arg list, don't push any params. 1602 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1603 1604 // In C++, the empty parameter-type-list must be spelled "void"; a 1605 // typedef of void is not permitted. 1606 if (getLangOptions().CPlusPlus && 1607 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1608 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1609 } 1610 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1611 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1612 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1613 } 1614 1615 NewFD->setParams(Context, &Params[0], Params.size()); 1616 } else if (R->getAsTypedefType()) { 1617 // When we're declaring a function with a typedef, as in the 1618 // following example, we'll need to synthesize (unnamed) 1619 // parameters for use in the declaration. 1620 // 1621 // @code 1622 // typedef void fn(int); 1623 // fn f; 1624 // @endcode 1625 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1626 if (!FT) { 1627 // This is a typedef of a function with no prototype, so we 1628 // don't need to do anything. 1629 } else if ((FT->getNumArgs() == 0) || 1630 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1631 FT->getArgType(0)->isVoidType())) { 1632 // This is a zero-argument function. We don't need to do anything. 1633 } else { 1634 // Synthesize a parameter for each argument type. 1635 llvm::SmallVector<ParmVarDecl*, 16> Params; 1636 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1637 ArgType != FT->arg_type_end(); ++ArgType) { 1638 Params.push_back(ParmVarDecl::Create(Context, DC, 1639 SourceLocation(), 0, 1640 *ArgType, VarDecl::None, 1641 0)); 1642 } 1643 1644 NewFD->setParams(Context, &Params[0], Params.size()); 1645 } 1646 } 1647 1648 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1649 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1650 else if (isa<CXXDestructorDecl>(NewFD)) { 1651 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1652 Record->setUserDeclaredDestructor(true); 1653 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1654 // user-defined destructor. 1655 Record->setPOD(false); 1656 } else if (CXXConversionDecl *Conversion = 1657 dyn_cast<CXXConversionDecl>(NewFD)) 1658 ActOnConversionDeclarator(Conversion); 1659 1660 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1661 if (NewFD->isOverloadedOperator() && 1662 CheckOverloadedOperatorDeclaration(NewFD)) 1663 NewFD->setInvalidDecl(); 1664 1665 // Merge the decl with the existing one if appropriate. Since C functions 1666 // are in a flat namespace, make sure we consider decls in outer scopes. 1667 if (PrevDecl && 1668 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1669 bool Redeclaration = false; 1670 1671 // If C++, determine whether NewFD is an overload of PrevDecl or 1672 // a declaration that requires merging. If it's an overload, 1673 // there's no more work to do here; we'll just add the new 1674 // function to the scope. 1675 OverloadedFunctionDecl::function_iterator MatchedDecl; 1676 if (!getLangOptions().CPlusPlus || 1677 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1678 Decl *OldDecl = PrevDecl; 1679 1680 // If PrevDecl was an overloaded function, extract the 1681 // FunctionDecl that matched. 1682 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1683 OldDecl = *MatchedDecl; 1684 1685 // NewFD and PrevDecl represent declarations that need to be 1686 // merged. 1687 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1688 1689 if (NewFD == 0) return 0; 1690 if (Redeclaration) { 1691 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1692 1693 // An out-of-line member function declaration must also be a 1694 // definition (C++ [dcl.meaning]p1). 1695 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1696 !InvalidDecl) { 1697 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1698 << D.getCXXScopeSpec().getRange(); 1699 NewFD->setInvalidDecl(); 1700 } 1701 } 1702 } 1703 1704 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1705 // The user tried to provide an out-of-line definition for a 1706 // member function, but there was no such member function 1707 // declared (C++ [class.mfct]p2). For example: 1708 // 1709 // class X { 1710 // void f() const; 1711 // }; 1712 // 1713 // void X::f() { } // ill-formed 1714 // 1715 // Complain about this problem, and attempt to suggest close 1716 // matches (e.g., those that differ only in cv-qualifiers and 1717 // whether the parameter types are references). 1718 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1719 << cast<CXXRecordDecl>(DC)->getDeclName() 1720 << D.getCXXScopeSpec().getRange(); 1721 InvalidDecl = true; 1722 1723 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1724 if (!PrevDecl) { 1725 // Nothing to suggest. 1726 } else if (OverloadedFunctionDecl *Ovl 1727 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1728 for (OverloadedFunctionDecl::function_iterator 1729 Func = Ovl->function_begin(), 1730 FuncEnd = Ovl->function_end(); 1731 Func != FuncEnd; ++Func) { 1732 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1733 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1734 1735 } 1736 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1737 // Suggest this no matter how mismatched it is; it's the only 1738 // thing we have. 1739 unsigned diag; 1740 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1741 diag = diag::note_member_def_close_match; 1742 else if (Method->getBody()) 1743 diag = diag::note_previous_definition; 1744 else 1745 diag = diag::note_previous_declaration; 1746 Diag(Method->getLocation(), diag); 1747 } 1748 1749 PrevDecl = 0; 1750 } 1751 } 1752 // Handle attributes. We need to have merged decls when handling attributes 1753 // (for example to check for conflicts, etc). 1754 ProcessDeclAttributes(NewFD, D); 1755 1756 if (getLangOptions().CPlusPlus) { 1757 // In C++, check default arguments now that we have merged decls. 1758 CheckCXXDefaultArguments(NewFD); 1759 1760 // An out-of-line member function declaration must also be a 1761 // definition (C++ [dcl.meaning]p1). 1762 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1763 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1764 << D.getCXXScopeSpec().getRange(); 1765 InvalidDecl = true; 1766 } 1767 } 1768 return NewFD; 1769} 1770 1771void Sema::InitializerElementNotConstant(const Expr *Init) { 1772 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1773 << Init->getSourceRange(); 1774} 1775 1776bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1777 switch (Init->getStmtClass()) { 1778 default: 1779 InitializerElementNotConstant(Init); 1780 return true; 1781 case Expr::ParenExprClass: { 1782 const ParenExpr* PE = cast<ParenExpr>(Init); 1783 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1784 } 1785 case Expr::CompoundLiteralExprClass: 1786 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1787 case Expr::DeclRefExprClass: 1788 case Expr::QualifiedDeclRefExprClass: { 1789 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1790 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1791 if (VD->hasGlobalStorage()) 1792 return false; 1793 InitializerElementNotConstant(Init); 1794 return true; 1795 } 1796 if (isa<FunctionDecl>(D)) 1797 return false; 1798 InitializerElementNotConstant(Init); 1799 return true; 1800 } 1801 case Expr::MemberExprClass: { 1802 const MemberExpr *M = cast<MemberExpr>(Init); 1803 if (M->isArrow()) 1804 return CheckAddressConstantExpression(M->getBase()); 1805 return CheckAddressConstantExpressionLValue(M->getBase()); 1806 } 1807 case Expr::ArraySubscriptExprClass: { 1808 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1809 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1810 return CheckAddressConstantExpression(ASE->getBase()) || 1811 CheckArithmeticConstantExpression(ASE->getIdx()); 1812 } 1813 case Expr::StringLiteralClass: 1814 case Expr::PredefinedExprClass: 1815 return false; 1816 case Expr::UnaryOperatorClass: { 1817 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1818 1819 // C99 6.6p9 1820 if (Exp->getOpcode() == UnaryOperator::Deref) 1821 return CheckAddressConstantExpression(Exp->getSubExpr()); 1822 1823 InitializerElementNotConstant(Init); 1824 return true; 1825 } 1826 } 1827} 1828 1829bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1830 switch (Init->getStmtClass()) { 1831 default: 1832 InitializerElementNotConstant(Init); 1833 return true; 1834 case Expr::ParenExprClass: 1835 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1836 case Expr::StringLiteralClass: 1837 case Expr::ObjCStringLiteralClass: 1838 return false; 1839 case Expr::CallExprClass: 1840 case Expr::CXXOperatorCallExprClass: 1841 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1842 if (cast<CallExpr>(Init)->isBuiltinCall() == 1843 Builtin::BI__builtin___CFStringMakeConstantString) 1844 return false; 1845 1846 InitializerElementNotConstant(Init); 1847 return true; 1848 1849 case Expr::UnaryOperatorClass: { 1850 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1851 1852 // C99 6.6p9 1853 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1854 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1855 1856 if (Exp->getOpcode() == UnaryOperator::Extension) 1857 return CheckAddressConstantExpression(Exp->getSubExpr()); 1858 1859 InitializerElementNotConstant(Init); 1860 return true; 1861 } 1862 case Expr::BinaryOperatorClass: { 1863 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1864 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1865 1866 Expr *PExp = Exp->getLHS(); 1867 Expr *IExp = Exp->getRHS(); 1868 if (IExp->getType()->isPointerType()) 1869 std::swap(PExp, IExp); 1870 1871 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1872 return CheckAddressConstantExpression(PExp) || 1873 CheckArithmeticConstantExpression(IExp); 1874 } 1875 case Expr::ImplicitCastExprClass: 1876 case Expr::CStyleCastExprClass: { 1877 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1878 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1879 // Check for implicit promotion 1880 if (SubExpr->getType()->isFunctionType() || 1881 SubExpr->getType()->isArrayType()) 1882 return CheckAddressConstantExpressionLValue(SubExpr); 1883 } 1884 1885 // Check for pointer->pointer cast 1886 if (SubExpr->getType()->isPointerType()) 1887 return CheckAddressConstantExpression(SubExpr); 1888 1889 if (SubExpr->getType()->isIntegralType()) { 1890 // Check for the special-case of a pointer->int->pointer cast; 1891 // this isn't standard, but some code requires it. See 1892 // PR2720 for an example. 1893 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1894 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1895 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1896 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1897 if (IntWidth >= PointerWidth) { 1898 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1899 } 1900 } 1901 } 1902 } 1903 if (SubExpr->getType()->isArithmeticType()) { 1904 return CheckArithmeticConstantExpression(SubExpr); 1905 } 1906 1907 InitializerElementNotConstant(Init); 1908 return true; 1909 } 1910 case Expr::ConditionalOperatorClass: { 1911 // FIXME: Should we pedwarn here? 1912 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1913 if (!Exp->getCond()->getType()->isArithmeticType()) { 1914 InitializerElementNotConstant(Init); 1915 return true; 1916 } 1917 if (CheckArithmeticConstantExpression(Exp->getCond())) 1918 return true; 1919 if (Exp->getLHS() && 1920 CheckAddressConstantExpression(Exp->getLHS())) 1921 return true; 1922 return CheckAddressConstantExpression(Exp->getRHS()); 1923 } 1924 case Expr::AddrLabelExprClass: 1925 return false; 1926 } 1927} 1928 1929static const Expr* FindExpressionBaseAddress(const Expr* E); 1930 1931static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1932 switch (E->getStmtClass()) { 1933 default: 1934 return E; 1935 case Expr::ParenExprClass: { 1936 const ParenExpr* PE = cast<ParenExpr>(E); 1937 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1938 } 1939 case Expr::MemberExprClass: { 1940 const MemberExpr *M = cast<MemberExpr>(E); 1941 if (M->isArrow()) 1942 return FindExpressionBaseAddress(M->getBase()); 1943 return FindExpressionBaseAddressLValue(M->getBase()); 1944 } 1945 case Expr::ArraySubscriptExprClass: { 1946 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1947 return FindExpressionBaseAddress(ASE->getBase()); 1948 } 1949 case Expr::UnaryOperatorClass: { 1950 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1951 1952 if (Exp->getOpcode() == UnaryOperator::Deref) 1953 return FindExpressionBaseAddress(Exp->getSubExpr()); 1954 1955 return E; 1956 } 1957 } 1958} 1959 1960static const Expr* FindExpressionBaseAddress(const Expr* E) { 1961 switch (E->getStmtClass()) { 1962 default: 1963 return E; 1964 case Expr::ParenExprClass: { 1965 const ParenExpr* PE = cast<ParenExpr>(E); 1966 return FindExpressionBaseAddress(PE->getSubExpr()); 1967 } 1968 case Expr::UnaryOperatorClass: { 1969 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1970 1971 // C99 6.6p9 1972 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1973 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1974 1975 if (Exp->getOpcode() == UnaryOperator::Extension) 1976 return FindExpressionBaseAddress(Exp->getSubExpr()); 1977 1978 return E; 1979 } 1980 case Expr::BinaryOperatorClass: { 1981 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1982 1983 Expr *PExp = Exp->getLHS(); 1984 Expr *IExp = Exp->getRHS(); 1985 if (IExp->getType()->isPointerType()) 1986 std::swap(PExp, IExp); 1987 1988 return FindExpressionBaseAddress(PExp); 1989 } 1990 case Expr::ImplicitCastExprClass: { 1991 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1992 1993 // Check for implicit promotion 1994 if (SubExpr->getType()->isFunctionType() || 1995 SubExpr->getType()->isArrayType()) 1996 return FindExpressionBaseAddressLValue(SubExpr); 1997 1998 // Check for pointer->pointer cast 1999 if (SubExpr->getType()->isPointerType()) 2000 return FindExpressionBaseAddress(SubExpr); 2001 2002 // We assume that we have an arithmetic expression here; 2003 // if we don't, we'll figure it out later 2004 return 0; 2005 } 2006 case Expr::CStyleCastExprClass: { 2007 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2008 2009 // Check for pointer->pointer cast 2010 if (SubExpr->getType()->isPointerType()) 2011 return FindExpressionBaseAddress(SubExpr); 2012 2013 // We assume that we have an arithmetic expression here; 2014 // if we don't, we'll figure it out later 2015 return 0; 2016 } 2017 } 2018} 2019 2020bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2021 switch (Init->getStmtClass()) { 2022 default: 2023 InitializerElementNotConstant(Init); 2024 return true; 2025 case Expr::ParenExprClass: { 2026 const ParenExpr* PE = cast<ParenExpr>(Init); 2027 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2028 } 2029 case Expr::FloatingLiteralClass: 2030 case Expr::IntegerLiteralClass: 2031 case Expr::CharacterLiteralClass: 2032 case Expr::ImaginaryLiteralClass: 2033 case Expr::TypesCompatibleExprClass: 2034 case Expr::CXXBoolLiteralExprClass: 2035 return false; 2036 case Expr::CallExprClass: 2037 case Expr::CXXOperatorCallExprClass: { 2038 const CallExpr *CE = cast<CallExpr>(Init); 2039 2040 // Allow any constant foldable calls to builtins. 2041 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 2042 return false; 2043 2044 InitializerElementNotConstant(Init); 2045 return true; 2046 } 2047 case Expr::DeclRefExprClass: 2048 case Expr::QualifiedDeclRefExprClass: { 2049 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2050 if (isa<EnumConstantDecl>(D)) 2051 return false; 2052 InitializerElementNotConstant(Init); 2053 return true; 2054 } 2055 case Expr::CompoundLiteralExprClass: 2056 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2057 // but vectors are allowed to be magic. 2058 if (Init->getType()->isVectorType()) 2059 return false; 2060 InitializerElementNotConstant(Init); 2061 return true; 2062 case Expr::UnaryOperatorClass: { 2063 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2064 2065 switch (Exp->getOpcode()) { 2066 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2067 // See C99 6.6p3. 2068 default: 2069 InitializerElementNotConstant(Init); 2070 return true; 2071 case UnaryOperator::OffsetOf: 2072 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2073 return false; 2074 InitializerElementNotConstant(Init); 2075 return true; 2076 case UnaryOperator::Extension: 2077 case UnaryOperator::LNot: 2078 case UnaryOperator::Plus: 2079 case UnaryOperator::Minus: 2080 case UnaryOperator::Not: 2081 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2082 } 2083 } 2084 case Expr::SizeOfAlignOfExprClass: { 2085 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2086 // Special check for void types, which are allowed as an extension 2087 if (Exp->getTypeOfArgument()->isVoidType()) 2088 return false; 2089 // alignof always evaluates to a constant. 2090 // FIXME: is sizeof(int[3.0]) a constant expression? 2091 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2092 InitializerElementNotConstant(Init); 2093 return true; 2094 } 2095 return false; 2096 } 2097 case Expr::BinaryOperatorClass: { 2098 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2099 2100 if (Exp->getLHS()->getType()->isArithmeticType() && 2101 Exp->getRHS()->getType()->isArithmeticType()) { 2102 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2103 CheckArithmeticConstantExpression(Exp->getRHS()); 2104 } 2105 2106 if (Exp->getLHS()->getType()->isPointerType() && 2107 Exp->getRHS()->getType()->isPointerType()) { 2108 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2109 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2110 2111 // Only allow a null (constant integer) base; we could 2112 // allow some additional cases if necessary, but this 2113 // is sufficient to cover offsetof-like constructs. 2114 if (!LHSBase && !RHSBase) { 2115 return CheckAddressConstantExpression(Exp->getLHS()) || 2116 CheckAddressConstantExpression(Exp->getRHS()); 2117 } 2118 } 2119 2120 InitializerElementNotConstant(Init); 2121 return true; 2122 } 2123 case Expr::ImplicitCastExprClass: 2124 case Expr::CStyleCastExprClass: { 2125 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2126 if (SubExpr->getType()->isArithmeticType()) 2127 return CheckArithmeticConstantExpression(SubExpr); 2128 2129 if (SubExpr->getType()->isPointerType()) { 2130 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2131 // If the pointer has a null base, this is an offsetof-like construct 2132 if (!Base) 2133 return CheckAddressConstantExpression(SubExpr); 2134 } 2135 2136 InitializerElementNotConstant(Init); 2137 return true; 2138 } 2139 case Expr::ConditionalOperatorClass: { 2140 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2141 2142 // If GNU extensions are disabled, we require all operands to be arithmetic 2143 // constant expressions. 2144 if (getLangOptions().NoExtensions) { 2145 return CheckArithmeticConstantExpression(Exp->getCond()) || 2146 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2147 CheckArithmeticConstantExpression(Exp->getRHS()); 2148 } 2149 2150 // Otherwise, we have to emulate some of the behavior of fold here. 2151 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2152 // because it can constant fold things away. To retain compatibility with 2153 // GCC code, we see if we can fold the condition to a constant (which we 2154 // should always be able to do in theory). If so, we only require the 2155 // specified arm of the conditional to be a constant. This is a horrible 2156 // hack, but is require by real world code that uses __builtin_constant_p. 2157 Expr::EvalResult EvalResult; 2158 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2159 EvalResult.HasSideEffects) { 2160 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2161 // won't be able to either. Use it to emit the diagnostic though. 2162 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2163 assert(Res && "Evaluate couldn't evaluate this constant?"); 2164 return Res; 2165 } 2166 2167 // Verify that the side following the condition is also a constant. 2168 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2169 if (EvalResult.Val.getInt() == 0) 2170 std::swap(TrueSide, FalseSide); 2171 2172 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2173 return true; 2174 2175 // Okay, the evaluated side evaluates to a constant, so we accept this. 2176 // Check to see if the other side is obviously not a constant. If so, 2177 // emit a warning that this is a GNU extension. 2178 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2179 Diag(Init->getExprLoc(), 2180 diag::ext_typecheck_expression_not_constant_but_accepted) 2181 << FalseSide->getSourceRange(); 2182 return false; 2183 } 2184 } 2185} 2186 2187bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2188 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2189 Init = DIE->getInit(); 2190 2191 Init = Init->IgnoreParens(); 2192 2193 if (Init->isEvaluatable(Context)) 2194 return false; 2195 2196 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2197 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2198 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2199 2200 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2201 return CheckForConstantInitializer(e->getInitializer(), DclT); 2202 2203 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2204 unsigned numInits = Exp->getNumInits(); 2205 for (unsigned i = 0; i < numInits; i++) { 2206 // FIXME: Need to get the type of the declaration for C++, 2207 // because it could be a reference? 2208 if (CheckForConstantInitializer(Exp->getInit(i), 2209 Exp->getInit(i)->getType())) 2210 return true; 2211 } 2212 return false; 2213 } 2214 2215 // FIXME: We can probably remove some of this code below, now that 2216 // Expr::Evaluate is doing the heavy lifting for scalars. 2217 2218 if (Init->isNullPointerConstant(Context)) 2219 return false; 2220 if (Init->getType()->isArithmeticType()) { 2221 QualType InitTy = Context.getCanonicalType(Init->getType()) 2222 .getUnqualifiedType(); 2223 if (InitTy == Context.BoolTy) { 2224 // Special handling for pointers implicitly cast to bool; 2225 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2226 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2227 Expr* SubE = ICE->getSubExpr(); 2228 if (SubE->getType()->isPointerType() || 2229 SubE->getType()->isArrayType() || 2230 SubE->getType()->isFunctionType()) { 2231 return CheckAddressConstantExpression(Init); 2232 } 2233 } 2234 } else if (InitTy->isIntegralType()) { 2235 Expr* SubE = 0; 2236 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2237 SubE = CE->getSubExpr(); 2238 // Special check for pointer cast to int; we allow as an extension 2239 // an address constant cast to an integer if the integer 2240 // is of an appropriate width (this sort of code is apparently used 2241 // in some places). 2242 // FIXME: Add pedwarn? 2243 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2244 if (SubE && (SubE->getType()->isPointerType() || 2245 SubE->getType()->isArrayType() || 2246 SubE->getType()->isFunctionType())) { 2247 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2248 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2249 if (IntWidth >= PointerWidth) 2250 return CheckAddressConstantExpression(Init); 2251 } 2252 } 2253 2254 return CheckArithmeticConstantExpression(Init); 2255 } 2256 2257 if (Init->getType()->isPointerType()) 2258 return CheckAddressConstantExpression(Init); 2259 2260 // An array type at the top level that isn't an init-list must 2261 // be a string literal 2262 if (Init->getType()->isArrayType()) 2263 return false; 2264 2265 if (Init->getType()->isFunctionType()) 2266 return false; 2267 2268 // Allow block exprs at top level. 2269 if (Init->getType()->isBlockPointerType()) 2270 return false; 2271 2272 // GCC cast to union extension 2273 // note: the validity of the cast expr is checked by CheckCastTypes() 2274 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2275 QualType T = C->getType(); 2276 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2277 } 2278 2279 InitializerElementNotConstant(Init); 2280 return true; 2281} 2282 2283void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2284 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2285} 2286 2287/// AddInitializerToDecl - Adds the initializer Init to the 2288/// declaration dcl. If DirectInit is true, this is C++ direct 2289/// initialization rather than copy initialization. 2290void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2291 Decl *RealDecl = static_cast<Decl *>(dcl); 2292 Expr *Init = static_cast<Expr *>(init.release()); 2293 assert(Init && "missing initializer"); 2294 2295 // If there is no declaration, there was an error parsing it. Just ignore 2296 // the initializer. 2297 if (RealDecl == 0) { 2298 delete Init; 2299 return; 2300 } 2301 2302 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2303 if (!VDecl) { 2304 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2305 RealDecl->setInvalidDecl(); 2306 return; 2307 } 2308 // Get the decls type and save a reference for later, since 2309 // CheckInitializerTypes may change it. 2310 QualType DclT = VDecl->getType(), SavT = DclT; 2311 if (VDecl->isBlockVarDecl()) { 2312 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2313 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2314 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2315 VDecl->setInvalidDecl(); 2316 } else if (!VDecl->isInvalidDecl()) { 2317 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2318 VDecl->getDeclName(), DirectInit)) 2319 VDecl->setInvalidDecl(); 2320 2321 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2322 if (!getLangOptions().CPlusPlus) { 2323 if (SC == VarDecl::Static) // C99 6.7.8p4. 2324 CheckForConstantInitializer(Init, DclT); 2325 } 2326 } 2327 } else if (VDecl->isFileVarDecl()) { 2328 if (VDecl->getStorageClass() == VarDecl::Extern) 2329 Diag(VDecl->getLocation(), diag::warn_extern_init); 2330 if (!VDecl->isInvalidDecl()) 2331 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2332 VDecl->getDeclName(), DirectInit)) 2333 VDecl->setInvalidDecl(); 2334 2335 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2336 if (!getLangOptions().CPlusPlus) { 2337 // C99 6.7.8p4. All file scoped initializers need to be constant. 2338 CheckForConstantInitializer(Init, DclT); 2339 } 2340 } 2341 // If the type changed, it means we had an incomplete type that was 2342 // completed by the initializer. For example: 2343 // int ary[] = { 1, 3, 5 }; 2344 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2345 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2346 VDecl->setType(DclT); 2347 Init->setType(DclT); 2348 } 2349 2350 // Attach the initializer to the decl. 2351 VDecl->setInit(Init); 2352 return; 2353} 2354 2355void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2356 Decl *RealDecl = static_cast<Decl *>(dcl); 2357 2358 // If there is no declaration, there was an error parsing it. Just ignore it. 2359 if (RealDecl == 0) 2360 return; 2361 2362 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2363 QualType Type = Var->getType(); 2364 // C++ [dcl.init.ref]p3: 2365 // The initializer can be omitted for a reference only in a 2366 // parameter declaration (8.3.5), in the declaration of a 2367 // function return type, in the declaration of a class member 2368 // within its class declaration (9.2), and where the extern 2369 // specifier is explicitly used. 2370 if (Type->isReferenceType() && 2371 Var->getStorageClass() != VarDecl::Extern && 2372 Var->getStorageClass() != VarDecl::PrivateExtern) { 2373 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2374 << Var->getDeclName() 2375 << SourceRange(Var->getLocation(), Var->getLocation()); 2376 Var->setInvalidDecl(); 2377 return; 2378 } 2379 2380 // C++ [dcl.init]p9: 2381 // 2382 // If no initializer is specified for an object, and the object 2383 // is of (possibly cv-qualified) non-POD class type (or array 2384 // thereof), the object shall be default-initialized; if the 2385 // object is of const-qualified type, the underlying class type 2386 // shall have a user-declared default constructor. 2387 if (getLangOptions().CPlusPlus) { 2388 QualType InitType = Type; 2389 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2390 InitType = Array->getElementType(); 2391 if (Var->getStorageClass() != VarDecl::Extern && 2392 Var->getStorageClass() != VarDecl::PrivateExtern && 2393 InitType->isRecordType()) { 2394 const CXXConstructorDecl *Constructor 2395 = PerformInitializationByConstructor(InitType, 0, 0, 2396 Var->getLocation(), 2397 SourceRange(Var->getLocation(), 2398 Var->getLocation()), 2399 Var->getDeclName(), 2400 IK_Default); 2401 if (!Constructor) 2402 Var->setInvalidDecl(); 2403 } 2404 } 2405 2406#if 0 2407 // FIXME: Temporarily disabled because we are not properly parsing 2408 // linkage specifications on declarations, e.g., 2409 // 2410 // extern "C" const CGPoint CGPointerZero; 2411 // 2412 // C++ [dcl.init]p9: 2413 // 2414 // If no initializer is specified for an object, and the 2415 // object is of (possibly cv-qualified) non-POD class type (or 2416 // array thereof), the object shall be default-initialized; if 2417 // the object is of const-qualified type, the underlying class 2418 // type shall have a user-declared default 2419 // constructor. Otherwise, if no initializer is specified for 2420 // an object, the object and its subobjects, if any, have an 2421 // indeterminate initial value; if the object or any of its 2422 // subobjects are of const-qualified type, the program is 2423 // ill-formed. 2424 // 2425 // This isn't technically an error in C, so we don't diagnose it. 2426 // 2427 // FIXME: Actually perform the POD/user-defined default 2428 // constructor check. 2429 if (getLangOptions().CPlusPlus && 2430 Context.getCanonicalType(Type).isConstQualified() && 2431 Var->getStorageClass() != VarDecl::Extern) 2432 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2433 << Var->getName() 2434 << SourceRange(Var->getLocation(), Var->getLocation()); 2435#endif 2436 } 2437} 2438 2439/// The declarators are chained together backwards, reverse the list. 2440Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2441 // Often we have single declarators, handle them quickly. 2442 Decl *GroupDecl = static_cast<Decl*>(group); 2443 if (GroupDecl == 0) 2444 return 0; 2445 2446 Decl *Group = dyn_cast<Decl>(GroupDecl); 2447 Decl *NewGroup = 0; 2448 if (Group->getNextDeclarator() == 0) 2449 NewGroup = Group; 2450 else { // reverse the list. 2451 while (Group) { 2452 Decl *Next = Group->getNextDeclarator(); 2453 Group->setNextDeclarator(NewGroup); 2454 NewGroup = Group; 2455 Group = Next; 2456 } 2457 } 2458 // Perform semantic analysis that depends on having fully processed both 2459 // the declarator and initializer. 2460 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2461 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2462 if (!IDecl) 2463 continue; 2464 QualType T = IDecl->getType(); 2465 2466 if (T->isVariableArrayType()) { 2467 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2468 2469 // FIXME: This won't give the correct result for 2470 // int a[10][n]; 2471 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2472 if (IDecl->isFileVarDecl()) { 2473 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2474 SizeRange; 2475 2476 IDecl->setInvalidDecl(); 2477 } else { 2478 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2479 // static storage duration, it shall not have a variable length array. 2480 if (IDecl->getStorageClass() == VarDecl::Static) { 2481 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2482 << SizeRange; 2483 IDecl->setInvalidDecl(); 2484 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2485 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2486 << SizeRange; 2487 IDecl->setInvalidDecl(); 2488 } 2489 } 2490 } else if (T->isVariablyModifiedType()) { 2491 if (IDecl->isFileVarDecl()) { 2492 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2493 IDecl->setInvalidDecl(); 2494 } else { 2495 if (IDecl->getStorageClass() == VarDecl::Extern) { 2496 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2497 IDecl->setInvalidDecl(); 2498 } 2499 } 2500 } 2501 2502 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2503 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2504 if (IDecl->isBlockVarDecl() && 2505 IDecl->getStorageClass() != VarDecl::Extern) { 2506 if (!IDecl->isInvalidDecl() && 2507 DiagnoseIncompleteType(IDecl->getLocation(), T, 2508 diag::err_typecheck_decl_incomplete_type)) 2509 IDecl->setInvalidDecl(); 2510 } 2511 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2512 // object that has file scope without an initializer, and without a 2513 // storage-class specifier or with the storage-class specifier "static", 2514 // constitutes a tentative definition. Note: A tentative definition with 2515 // external linkage is valid (C99 6.2.2p5). 2516 if (isTentativeDefinition(IDecl)) { 2517 if (T->isIncompleteArrayType()) { 2518 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2519 // array to be completed. Don't issue a diagnostic. 2520 } else if (!IDecl->isInvalidDecl() && 2521 DiagnoseIncompleteType(IDecl->getLocation(), T, 2522 diag::err_typecheck_decl_incomplete_type)) 2523 // C99 6.9.2p3: If the declaration of an identifier for an object is 2524 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2525 // declared type shall not be an incomplete type. 2526 IDecl->setInvalidDecl(); 2527 } 2528 if (IDecl->isFileVarDecl()) 2529 CheckForFileScopedRedefinitions(S, IDecl); 2530 } 2531 return NewGroup; 2532} 2533 2534/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2535/// to introduce parameters into function prototype scope. 2536Sema::DeclTy * 2537Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2538 const DeclSpec &DS = D.getDeclSpec(); 2539 2540 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2541 VarDecl::StorageClass StorageClass = VarDecl::None; 2542 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2543 StorageClass = VarDecl::Register; 2544 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2545 Diag(DS.getStorageClassSpecLoc(), 2546 diag::err_invalid_storage_class_in_func_decl); 2547 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2548 } 2549 if (DS.isThreadSpecified()) { 2550 Diag(DS.getThreadSpecLoc(), 2551 diag::err_invalid_storage_class_in_func_decl); 2552 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2553 } 2554 2555 // Check that there are no default arguments inside the type of this 2556 // parameter (C++ only). 2557 if (getLangOptions().CPlusPlus) 2558 CheckExtraCXXDefaultArguments(D); 2559 2560 // In this context, we *do not* check D.getInvalidType(). If the declarator 2561 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2562 // though it will not reflect the user specified type. 2563 QualType parmDeclType = GetTypeForDeclarator(D, S); 2564 2565 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2566 2567 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2568 // Can this happen for params? We already checked that they don't conflict 2569 // among each other. Here they can only shadow globals, which is ok. 2570 IdentifierInfo *II = D.getIdentifier(); 2571 if (II) { 2572 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2573 if (PrevDecl->isTemplateParameter()) { 2574 // Maybe we will complain about the shadowed template parameter. 2575 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2576 // Just pretend that we didn't see the previous declaration. 2577 PrevDecl = 0; 2578 } else if (S->isDeclScope(PrevDecl)) { 2579 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2580 2581 // Recover by removing the name 2582 II = 0; 2583 D.SetIdentifier(0, D.getIdentifierLoc()); 2584 } 2585 } 2586 } 2587 2588 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2589 // Doing the promotion here has a win and a loss. The win is the type for 2590 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2591 // code generator). The loss is the orginal type isn't preserved. For example: 2592 // 2593 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2594 // int blockvardecl[5]; 2595 // sizeof(parmvardecl); // size == 4 2596 // sizeof(blockvardecl); // size == 20 2597 // } 2598 // 2599 // For expressions, all implicit conversions are captured using the 2600 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2601 // 2602 // FIXME: If a source translation tool needs to see the original type, then 2603 // we need to consider storing both types (in ParmVarDecl)... 2604 // 2605 if (parmDeclType->isArrayType()) { 2606 // int x[restrict 4] -> int *restrict 2607 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2608 } else if (parmDeclType->isFunctionType()) 2609 parmDeclType = Context.getPointerType(parmDeclType); 2610 2611 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2612 D.getIdentifierLoc(), II, 2613 parmDeclType, StorageClass, 2614 0); 2615 2616 if (D.getInvalidType()) 2617 New->setInvalidDecl(); 2618 2619 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2620 if (D.getCXXScopeSpec().isSet()) { 2621 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2622 << D.getCXXScopeSpec().getRange(); 2623 New->setInvalidDecl(); 2624 } 2625 2626 // Add the parameter declaration into this scope. 2627 S->AddDecl(New); 2628 if (II) 2629 IdResolver.AddDecl(New); 2630 2631 ProcessDeclAttributes(New, D); 2632 return New; 2633 2634} 2635 2636void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2637 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2638 "Not a function declarator!"); 2639 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2640 2641 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2642 // for a K&R function. 2643 if (!FTI.hasPrototype) { 2644 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2645 if (FTI.ArgInfo[i].Param == 0) { 2646 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2647 << FTI.ArgInfo[i].Ident; 2648 // Implicitly declare the argument as type 'int' for lack of a better 2649 // type. 2650 DeclSpec DS; 2651 const char* PrevSpec; // unused 2652 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2653 PrevSpec); 2654 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2655 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2656 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2657 } 2658 } 2659 } 2660} 2661 2662Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2663 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2664 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2665 "Not a function declarator!"); 2666 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2667 2668 if (FTI.hasPrototype) { 2669 // FIXME: Diagnose arguments without names in C. 2670 } 2671 2672 Scope *ParentScope = FnBodyScope->getParent(); 2673 2674 return ActOnStartOfFunctionDef(FnBodyScope, 2675 ActOnDeclarator(ParentScope, D, 0, 2676 /*IsFunctionDefinition=*/true)); 2677} 2678 2679Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2680 Decl *decl = static_cast<Decl*>(D); 2681 FunctionDecl *FD = cast<FunctionDecl>(decl); 2682 2683 // See if this is a redefinition. 2684 const FunctionDecl *Definition; 2685 if (FD->getBody(Definition)) { 2686 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2687 Diag(Definition->getLocation(), diag::note_previous_definition); 2688 } 2689 2690 PushDeclContext(FnBodyScope, FD); 2691 2692 // Check the validity of our function parameters 2693 CheckParmsForFunctionDef(FD); 2694 2695 // Introduce our parameters into the function scope 2696 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2697 ParmVarDecl *Param = FD->getParamDecl(p); 2698 Param->setOwningFunction(FD); 2699 2700 // If this has an identifier, add it to the scope stack. 2701 if (Param->getIdentifier()) 2702 PushOnScopeChains(Param, FnBodyScope); 2703 } 2704 2705 // Checking attributes of current function definition 2706 // dllimport attribute. 2707 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2708 // dllimport attribute cannot be applied to definition. 2709 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2710 Diag(FD->getLocation(), 2711 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2712 << "dllimport"; 2713 FD->setInvalidDecl(); 2714 return FD; 2715 } else { 2716 // If a symbol previously declared dllimport is later defined, the 2717 // attribute is ignored in subsequent references, and a warning is 2718 // emitted. 2719 Diag(FD->getLocation(), 2720 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2721 << FD->getNameAsCString() << "dllimport"; 2722 } 2723 } 2724 return FD; 2725} 2726 2727Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2728 Decl *dcl = static_cast<Decl *>(D); 2729 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2730 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2731 FD->setBody(Body); 2732 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2733 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2734 MD->setBody((Stmt*)Body); 2735 } else 2736 return 0; 2737 PopDeclContext(); 2738 // Verify and clean out per-function state. 2739 2740 // Check goto/label use. 2741 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2742 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2743 // Verify that we have no forward references left. If so, there was a goto 2744 // or address of a label taken, but no definition of it. Label fwd 2745 // definitions are indicated with a null substmt. 2746 if (I->second->getSubStmt() == 0) { 2747 LabelStmt *L = I->second; 2748 // Emit error. 2749 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2750 2751 // At this point, we have gotos that use the bogus label. Stitch it into 2752 // the function body so that they aren't leaked and that the AST is well 2753 // formed. 2754 if (Body) { 2755 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2756 cast<CompoundStmt>(Body)->push_back(L); 2757 } else { 2758 // The whole function wasn't parsed correctly, just delete this. 2759 delete L; 2760 } 2761 } 2762 } 2763 LabelMap.clear(); 2764 2765 return D; 2766} 2767 2768/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2769/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2770NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2771 IdentifierInfo &II, Scope *S) { 2772 // Extension in C99. Legal in C90, but warn about it. 2773 if (getLangOptions().C99) 2774 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2775 else 2776 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2777 2778 // FIXME: handle stuff like: 2779 // void foo() { extern float X(); } 2780 // void bar() { X(); } <-- implicit decl for X in another scope. 2781 2782 // Set a Declarator for the implicit definition: int foo(); 2783 const char *Dummy; 2784 DeclSpec DS; 2785 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2786 Error = Error; // Silence warning. 2787 assert(!Error && "Error setting up implicit decl!"); 2788 Declarator D(DS, Declarator::BlockContext); 2789 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D)); 2790 D.SetIdentifier(&II, Loc); 2791 2792 // Insert this function into translation-unit scope. 2793 2794 DeclContext *PrevDC = CurContext; 2795 CurContext = Context.getTranslationUnitDecl(); 2796 2797 FunctionDecl *FD = 2798 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2799 FD->setImplicit(); 2800 2801 CurContext = PrevDC; 2802 2803 return FD; 2804} 2805 2806 2807TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2808 Decl *LastDeclarator) { 2809 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2810 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2811 2812 // Scope manipulation handled by caller. 2813 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2814 D.getIdentifierLoc(), 2815 D.getIdentifier(), 2816 T); 2817 NewTD->setNextDeclarator(LastDeclarator); 2818 if (D.getInvalidType()) 2819 NewTD->setInvalidDecl(); 2820 return NewTD; 2821} 2822 2823/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2824/// former case, Name will be non-null. In the later case, Name will be null. 2825/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2826/// reference/declaration/definition of a tag. 2827Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2828 SourceLocation KWLoc, const CXXScopeSpec &SS, 2829 IdentifierInfo *Name, SourceLocation NameLoc, 2830 AttributeList *Attr, 2831 MultiTemplateParamsArg TemplateParameterLists) { 2832 // If this is not a definition, it must have a name. 2833 assert((Name != 0 || TK == TK_Definition) && 2834 "Nameless record must be a definition!"); 2835 2836 TagDecl::TagKind Kind; 2837 switch (TagSpec) { 2838 default: assert(0 && "Unknown tag type!"); 2839 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2840 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2841 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2842 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2843 } 2844 2845 DeclContext *SearchDC = CurContext; 2846 DeclContext *DC = CurContext; 2847 DeclContext *LexicalContext = CurContext; 2848 Decl *PrevDecl = 0; 2849 2850 bool Invalid = false; 2851 2852 if (Name && SS.isNotEmpty()) { 2853 // We have a nested-name tag ('struct foo::bar'). 2854 2855 // Check for invalid 'foo::'. 2856 if (SS.isInvalid()) { 2857 Name = 0; 2858 goto CreateNewDecl; 2859 } 2860 2861 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2862 // Look-up name inside 'foo::'. 2863 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC) 2864 .getAsDecl()); 2865 2866 // A tag 'foo::bar' must already exist. 2867 if (PrevDecl == 0) { 2868 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2869 Name = 0; 2870 goto CreateNewDecl; 2871 } 2872 } else if (Name) { 2873 // If this is a named struct, check to see if there was a previous forward 2874 // declaration or definition. 2875 PrevDecl = dyn_cast_or_null<NamedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S) 2876 .getAsDecl()); 2877 2878 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2879 // FIXME: This makes sure that we ignore the contexts associated 2880 // with C structs, unions, and enums when looking for a matching 2881 // tag declaration or definition. See the similar lookup tweak 2882 // in Sema::LookupDecl; is there a better way to deal with this? 2883 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2884 SearchDC = SearchDC->getParent(); 2885 } 2886 } 2887 2888 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2889 // Maybe we will complain about the shadowed template parameter. 2890 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2891 // Just pretend that we didn't see the previous declaration. 2892 PrevDecl = 0; 2893 } 2894 2895 if (PrevDecl) { 2896 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2897 "unexpected Decl type"); 2898 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2899 // If this is a use of a previous tag, or if the tag is already declared 2900 // in the same scope (so that the definition/declaration completes or 2901 // rementions the tag), reuse the decl. 2902 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2903 // Make sure that this wasn't declared as an enum and now used as a 2904 // struct or something similar. 2905 if (PrevTagDecl->getTagKind() != Kind) { 2906 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2907 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2908 // Recover by making this an anonymous redefinition. 2909 Name = 0; 2910 PrevDecl = 0; 2911 Invalid = true; 2912 } else { 2913 // If this is a use, just return the declaration we found. 2914 2915 // FIXME: In the future, return a variant or some other clue 2916 // for the consumer of this Decl to know it doesn't own it. 2917 // For our current ASTs this shouldn't be a problem, but will 2918 // need to be changed with DeclGroups. 2919 if (TK == TK_Reference) 2920 return PrevDecl; 2921 2922 // Diagnose attempts to redefine a tag. 2923 if (TK == TK_Definition) { 2924 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2925 Diag(NameLoc, diag::err_redefinition) << Name; 2926 Diag(Def->getLocation(), diag::note_previous_definition); 2927 // If this is a redefinition, recover by making this 2928 // struct be anonymous, which will make any later 2929 // references get the previous definition. 2930 Name = 0; 2931 PrevDecl = 0; 2932 Invalid = true; 2933 } else { 2934 // If the type is currently being defined, complain 2935 // about a nested redefinition. 2936 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2937 if (Tag->isBeingDefined()) { 2938 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2939 Diag(PrevTagDecl->getLocation(), 2940 diag::note_previous_definition); 2941 Name = 0; 2942 PrevDecl = 0; 2943 Invalid = true; 2944 } 2945 } 2946 2947 // Okay, this is definition of a previously declared or referenced 2948 // tag PrevDecl. We're going to create a new Decl for it. 2949 } 2950 } 2951 // If we get here we have (another) forward declaration or we 2952 // have a definition. Just create a new decl. 2953 } else { 2954 // If we get here, this is a definition of a new tag type in a nested 2955 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2956 // new decl/type. We set PrevDecl to NULL so that the entities 2957 // have distinct types. 2958 PrevDecl = 0; 2959 } 2960 // If we get here, we're going to create a new Decl. If PrevDecl 2961 // is non-NULL, it's a definition of the tag declared by 2962 // PrevDecl. If it's NULL, we have a new definition. 2963 } else { 2964 // PrevDecl is a namespace. 2965 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2966 // The tag name clashes with a namespace name, issue an error and 2967 // recover by making this tag be anonymous. 2968 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2969 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2970 Name = 0; 2971 PrevDecl = 0; 2972 Invalid = true; 2973 } else { 2974 // The existing declaration isn't relevant to us; we're in a 2975 // new scope, so clear out the previous declaration. 2976 PrevDecl = 0; 2977 } 2978 } 2979 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2980 (Kind != TagDecl::TK_enum)) { 2981 // C++ [basic.scope.pdecl]p5: 2982 // -- for an elaborated-type-specifier of the form 2983 // 2984 // class-key identifier 2985 // 2986 // if the elaborated-type-specifier is used in the 2987 // decl-specifier-seq or parameter-declaration-clause of a 2988 // function defined in namespace scope, the identifier is 2989 // declared as a class-name in the namespace that contains 2990 // the declaration; otherwise, except as a friend 2991 // declaration, the identifier is declared in the smallest 2992 // non-class, non-function-prototype scope that contains the 2993 // declaration. 2994 // 2995 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2996 // C structs and unions. 2997 2998 // Find the context where we'll be declaring the tag. 2999 // FIXME: We would like to maintain the current DeclContext as the 3000 // lexical context, 3001 while (DC->isRecord()) 3002 DC = DC->getParent(); 3003 LexicalContext = DC; 3004 3005 // Find the scope where we'll be declaring the tag. 3006 while (S->isClassScope() || 3007 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3008 ((S->getFlags() & Scope::DeclScope) == 0) || 3009 (S->getEntity() && 3010 ((DeclContext *)S->getEntity())->isTransparentContext())) 3011 S = S->getParent(); 3012 } 3013 3014CreateNewDecl: 3015 3016 // If there is an identifier, use the location of the identifier as the 3017 // location of the decl, otherwise use the location of the struct/union 3018 // keyword. 3019 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3020 3021 // Otherwise, create a new declaration. If there is a previous 3022 // declaration of the same entity, the two will be linked via 3023 // PrevDecl. 3024 TagDecl *New; 3025 3026 if (Kind == TagDecl::TK_enum) { 3027 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3028 // enum X { A, B, C } D; D should chain to X. 3029 New = EnumDecl::Create(Context, DC, Loc, Name, 3030 cast_or_null<EnumDecl>(PrevDecl)); 3031 // If this is an undefined enum, warn. 3032 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3033 } else { 3034 // struct/union/class 3035 3036 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3037 // struct X { int A; } D; D should chain to X. 3038 if (getLangOptions().CPlusPlus) 3039 // FIXME: Look for a way to use RecordDecl for simple structs. 3040 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 3041 cast_or_null<CXXRecordDecl>(PrevDecl)); 3042 else 3043 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 3044 cast_or_null<RecordDecl>(PrevDecl)); 3045 } 3046 3047 if (Kind != TagDecl::TK_enum) { 3048 // Handle #pragma pack: if the #pragma pack stack has non-default 3049 // alignment, make up a packed attribute for this decl. These 3050 // attributes are checked when the ASTContext lays out the 3051 // structure. 3052 // 3053 // It is important for implementing the correct semantics that this 3054 // happen here (in act on tag decl). The #pragma pack stack is 3055 // maintained as a result of parser callbacks which can occur at 3056 // many points during the parsing of a struct declaration (because 3057 // the #pragma tokens are effectively skipped over during the 3058 // parsing of the struct). 3059 if (unsigned Alignment = PackContext.getAlignment()) 3060 New->addAttr(new PackedAttr(Alignment * 8)); 3061 } 3062 3063 if (Invalid) 3064 New->setInvalidDecl(); 3065 3066 if (Attr) 3067 ProcessDeclAttributeList(New, Attr); 3068 3069 // If we're declaring or defining a tag in function prototype scope 3070 // in C, note that this type can only be used within the function. 3071 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3072 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3073 3074 // Set the lexical context. If the tag has a C++ scope specifier, the 3075 // lexical context will be different from the semantic context. 3076 New->setLexicalDeclContext(LexicalContext); 3077 3078 if (TK == TK_Definition) 3079 New->startDefinition(); 3080 3081 // If this has an identifier, add it to the scope stack. 3082 if (Name) { 3083 S = getNonFieldDeclScope(S); 3084 3085 // Add it to the decl chain. 3086 if (LexicalContext != CurContext) { 3087 // FIXME: PushOnScopeChains should not rely on CurContext! 3088 DeclContext *OldContext = CurContext; 3089 CurContext = LexicalContext; 3090 PushOnScopeChains(New, S); 3091 CurContext = OldContext; 3092 } else 3093 PushOnScopeChains(New, S); 3094 } else { 3095 LexicalContext->addDecl(New); 3096 } 3097 3098 return New; 3099} 3100 3101void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3102 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3103 3104 // Enter the tag context. 3105 PushDeclContext(S, Tag); 3106 3107 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3108 FieldCollector->StartClass(); 3109 3110 if (Record->getIdentifier()) { 3111 // C++ [class]p2: 3112 // [...] The class-name is also inserted into the scope of the 3113 // class itself; this is known as the injected-class-name. For 3114 // purposes of access checking, the injected-class-name is treated 3115 // as if it were a public member name. 3116 RecordDecl *InjectedClassName 3117 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3118 CurContext, Record->getLocation(), 3119 Record->getIdentifier(), Record); 3120 InjectedClassName->setImplicit(); 3121 PushOnScopeChains(InjectedClassName, S); 3122 } 3123 } 3124} 3125 3126void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3127 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3128 3129 if (isa<CXXRecordDecl>(Tag)) 3130 FieldCollector->FinishClass(); 3131 3132 // Exit this scope of this tag's definition. 3133 PopDeclContext(); 3134 3135 // Notify the consumer that we've defined a tag. 3136 Consumer.HandleTagDeclDefinition(Tag); 3137} 3138 3139/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3140/// types into constant array types in certain situations which would otherwise 3141/// be errors (for GCC compatibility). 3142static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3143 ASTContext &Context) { 3144 // This method tries to turn a variable array into a constant 3145 // array even when the size isn't an ICE. This is necessary 3146 // for compatibility with code that depends on gcc's buggy 3147 // constant expression folding, like struct {char x[(int)(char*)2];} 3148 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3149 if (!VLATy) return QualType(); 3150 3151 Expr::EvalResult EvalResult; 3152 if (!VLATy->getSizeExpr() || 3153 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3154 return QualType(); 3155 3156 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3157 llvm::APSInt &Res = EvalResult.Val.getInt(); 3158 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3159 return Context.getConstantArrayType(VLATy->getElementType(), 3160 Res, ArrayType::Normal, 0); 3161 return QualType(); 3162} 3163 3164bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3165 QualType FieldTy, const Expr *BitWidth) { 3166 // FIXME: 6.7.2.1p4 - verify the field type. 3167 3168 llvm::APSInt Value; 3169 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3170 return true; 3171 3172 // Zero-width bitfield is ok for anonymous field. 3173 if (Value == 0 && FieldName) 3174 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3175 3176 if (Value.isNegative()) 3177 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3178 3179 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3180 // FIXME: We won't need the 0 size once we check that the field type is valid. 3181 if (TypeSize && Value.getZExtValue() > TypeSize) 3182 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3183 << FieldName << (unsigned)TypeSize; 3184 3185 return false; 3186} 3187 3188/// ActOnField - Each field of a struct/union/class is passed into this in order 3189/// to create a FieldDecl object for it. 3190Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3191 SourceLocation DeclStart, 3192 Declarator &D, ExprTy *BitfieldWidth) { 3193 IdentifierInfo *II = D.getIdentifier(); 3194 Expr *BitWidth = (Expr*)BitfieldWidth; 3195 SourceLocation Loc = DeclStart; 3196 RecordDecl *Record = (RecordDecl *)TagD; 3197 if (II) Loc = D.getIdentifierLoc(); 3198 3199 // FIXME: Unnamed fields can be handled in various different ways, for 3200 // example, unnamed unions inject all members into the struct namespace! 3201 3202 QualType T = GetTypeForDeclarator(D, S); 3203 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3204 bool InvalidDecl = false; 3205 3206 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3207 // than a variably modified type. 3208 if (T->isVariablyModifiedType()) { 3209 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3210 if (!FixedTy.isNull()) { 3211 Diag(Loc, diag::warn_illegal_constant_array_size); 3212 T = FixedTy; 3213 } else { 3214 Diag(Loc, diag::err_typecheck_field_variable_size); 3215 T = Context.IntTy; 3216 InvalidDecl = true; 3217 } 3218 } 3219 3220 if (BitWidth) { 3221 if (VerifyBitField(Loc, II, T, BitWidth)) 3222 InvalidDecl = true; 3223 } else { 3224 // Not a bitfield. 3225 3226 // validate II. 3227 3228 } 3229 3230 // FIXME: Chain fielddecls together. 3231 FieldDecl *NewFD; 3232 3233 NewFD = FieldDecl::Create(Context, Record, 3234 Loc, II, T, BitWidth, 3235 D.getDeclSpec().getStorageClassSpec() == 3236 DeclSpec::SCS_mutable); 3237 3238 if (II) { 3239 Decl *PrevDecl 3240 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3241 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3242 && !isa<TagDecl>(PrevDecl)) { 3243 Diag(Loc, diag::err_duplicate_member) << II; 3244 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3245 NewFD->setInvalidDecl(); 3246 Record->setInvalidDecl(); 3247 } 3248 } 3249 3250 if (getLangOptions().CPlusPlus) { 3251 CheckExtraCXXDefaultArguments(D); 3252 if (!T->isPODType()) 3253 cast<CXXRecordDecl>(Record)->setPOD(false); 3254 } 3255 3256 ProcessDeclAttributes(NewFD, D); 3257 3258 if (D.getInvalidType() || InvalidDecl) 3259 NewFD->setInvalidDecl(); 3260 3261 if (II) { 3262 PushOnScopeChains(NewFD, S); 3263 } else 3264 Record->addDecl(NewFD); 3265 3266 return NewFD; 3267} 3268 3269/// TranslateIvarVisibility - Translate visibility from a token ID to an 3270/// AST enum value. 3271static ObjCIvarDecl::AccessControl 3272TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3273 switch (ivarVisibility) { 3274 default: assert(0 && "Unknown visitibility kind"); 3275 case tok::objc_private: return ObjCIvarDecl::Private; 3276 case tok::objc_public: return ObjCIvarDecl::Public; 3277 case tok::objc_protected: return ObjCIvarDecl::Protected; 3278 case tok::objc_package: return ObjCIvarDecl::Package; 3279 } 3280} 3281 3282/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3283/// in order to create an IvarDecl object for it. 3284Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3285 SourceLocation DeclStart, 3286 Declarator &D, ExprTy *BitfieldWidth, 3287 tok::ObjCKeywordKind Visibility) { 3288 3289 IdentifierInfo *II = D.getIdentifier(); 3290 Expr *BitWidth = (Expr*)BitfieldWidth; 3291 SourceLocation Loc = DeclStart; 3292 if (II) Loc = D.getIdentifierLoc(); 3293 3294 // FIXME: Unnamed fields can be handled in various different ways, for 3295 // example, unnamed unions inject all members into the struct namespace! 3296 3297 QualType T = GetTypeForDeclarator(D, S); 3298 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3299 bool InvalidDecl = false; 3300 3301 if (BitWidth) { 3302 // TODO: Validate. 3303 //printf("WARNING: BITFIELDS IGNORED!\n"); 3304 3305 // 6.7.2.1p3 3306 // 6.7.2.1p4 3307 3308 } else { 3309 // Not a bitfield. 3310 3311 // validate II. 3312 3313 } 3314 3315 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3316 // than a variably modified type. 3317 if (T->isVariablyModifiedType()) { 3318 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3319 InvalidDecl = true; 3320 } 3321 3322 // Get the visibility (access control) for this ivar. 3323 ObjCIvarDecl::AccessControl ac = 3324 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3325 : ObjCIvarDecl::None; 3326 3327 // Construct the decl. 3328 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3329 (Expr *)BitfieldWidth); 3330 3331 if (II) { 3332 Decl *PrevDecl 3333 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3334 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3335 && !isa<TagDecl>(PrevDecl)) { 3336 Diag(Loc, diag::err_duplicate_member) << II; 3337 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3338 NewID->setInvalidDecl(); 3339 } 3340 } 3341 3342 // Process attributes attached to the ivar. 3343 ProcessDeclAttributes(NewID, D); 3344 3345 if (D.getInvalidType() || InvalidDecl) 3346 NewID->setInvalidDecl(); 3347 3348 if (II) { 3349 // FIXME: When interfaces are DeclContexts, we'll need to add 3350 // these to the interface. 3351 S->AddDecl(NewID); 3352 IdResolver.AddDecl(NewID); 3353 } 3354 3355 return NewID; 3356} 3357 3358void Sema::ActOnFields(Scope* S, 3359 SourceLocation RecLoc, DeclTy *RecDecl, 3360 DeclTy **Fields, unsigned NumFields, 3361 SourceLocation LBrac, SourceLocation RBrac, 3362 AttributeList *Attr) { 3363 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3364 assert(EnclosingDecl && "missing record or interface decl"); 3365 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3366 3367 // Verify that all the fields are okay. 3368 unsigned NumNamedMembers = 0; 3369 llvm::SmallVector<FieldDecl*, 32> RecFields; 3370 3371 for (unsigned i = 0; i != NumFields; ++i) { 3372 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3373 assert(FD && "missing field decl"); 3374 3375 // Get the type for the field. 3376 Type *FDTy = FD->getType().getTypePtr(); 3377 3378 if (!FD->isAnonymousStructOrUnion()) { 3379 // Remember all fields written by the user. 3380 RecFields.push_back(FD); 3381 } 3382 3383 // C99 6.7.2.1p2 - A field may not be a function type. 3384 if (FDTy->isFunctionType()) { 3385 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3386 << FD->getDeclName(); 3387 FD->setInvalidDecl(); 3388 EnclosingDecl->setInvalidDecl(); 3389 continue; 3390 } 3391 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3392 if (FDTy->isIncompleteType()) { 3393 if (!Record) { // Incomplete ivar type is always an error. 3394 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3395 diag::err_field_incomplete); 3396 FD->setInvalidDecl(); 3397 EnclosingDecl->setInvalidDecl(); 3398 continue; 3399 } 3400 if (i != NumFields-1 || // ... that the last member ... 3401 !Record->isStruct() || // ... of a structure ... 3402 !FDTy->isArrayType()) { //... may have incomplete array type. 3403 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3404 diag::err_field_incomplete); 3405 FD->setInvalidDecl(); 3406 EnclosingDecl->setInvalidDecl(); 3407 continue; 3408 } 3409 if (NumNamedMembers < 1) { //... must have more than named member ... 3410 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3411 << FD->getDeclName(); 3412 FD->setInvalidDecl(); 3413 EnclosingDecl->setInvalidDecl(); 3414 continue; 3415 } 3416 // Okay, we have a legal flexible array member at the end of the struct. 3417 if (Record) 3418 Record->setHasFlexibleArrayMember(true); 3419 } 3420 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3421 /// field of another structure or the element of an array. 3422 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3423 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3424 // If this is a member of a union, then entire union becomes "flexible". 3425 if (Record && Record->isUnion()) { 3426 Record->setHasFlexibleArrayMember(true); 3427 } else { 3428 // If this is a struct/class and this is not the last element, reject 3429 // it. Note that GCC supports variable sized arrays in the middle of 3430 // structures. 3431 if (i != NumFields-1) { 3432 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3433 << FD->getDeclName(); 3434 FD->setInvalidDecl(); 3435 EnclosingDecl->setInvalidDecl(); 3436 continue; 3437 } 3438 // We support flexible arrays at the end of structs in other structs 3439 // as an extension. 3440 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3441 << FD->getDeclName(); 3442 if (Record) 3443 Record->setHasFlexibleArrayMember(true); 3444 } 3445 } 3446 } 3447 /// A field cannot be an Objective-c object 3448 if (FDTy->isObjCInterfaceType()) { 3449 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3450 << FD->getDeclName(); 3451 FD->setInvalidDecl(); 3452 EnclosingDecl->setInvalidDecl(); 3453 continue; 3454 } 3455 // Keep track of the number of named members. 3456 if (FD->getIdentifier()) 3457 ++NumNamedMembers; 3458 } 3459 3460 // Okay, we successfully defined 'Record'. 3461 if (Record) { 3462 Record->completeDefinition(Context); 3463 } else { 3464 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3465 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3466 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3467 // Must enforce the rule that ivars in the base classes may not be 3468 // duplicates. 3469 if (ID->getSuperClass()) { 3470 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3471 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3472 ObjCIvarDecl* Ivar = (*IVI); 3473 IdentifierInfo *II = Ivar->getIdentifier(); 3474 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3475 if (prevIvar) { 3476 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3477 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3478 } 3479 } 3480 } 3481 } 3482 else if (ObjCImplementationDecl *IMPDecl = 3483 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3484 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3485 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3486 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3487 } 3488 } 3489 3490 if (Attr) 3491 ProcessDeclAttributeList(Record, Attr); 3492} 3493 3494Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3495 DeclTy *lastEnumConst, 3496 SourceLocation IdLoc, IdentifierInfo *Id, 3497 SourceLocation EqualLoc, ExprTy *val) { 3498 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3499 EnumConstantDecl *LastEnumConst = 3500 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3501 Expr *Val = static_cast<Expr*>(val); 3502 3503 // The scope passed in may not be a decl scope. Zip up the scope tree until 3504 // we find one that is. 3505 S = getNonFieldDeclScope(S); 3506 3507 // Verify that there isn't already something declared with this name in this 3508 // scope. 3509 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3510 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3511 // Maybe we will complain about the shadowed template parameter. 3512 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3513 // Just pretend that we didn't see the previous declaration. 3514 PrevDecl = 0; 3515 } 3516 3517 if (PrevDecl) { 3518 // When in C++, we may get a TagDecl with the same name; in this case the 3519 // enum constant will 'hide' the tag. 3520 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3521 "Received TagDecl when not in C++!"); 3522 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3523 if (isa<EnumConstantDecl>(PrevDecl)) 3524 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3525 else 3526 Diag(IdLoc, diag::err_redefinition) << Id; 3527 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3528 delete Val; 3529 return 0; 3530 } 3531 } 3532 3533 llvm::APSInt EnumVal(32); 3534 QualType EltTy; 3535 if (Val) { 3536 // Make sure to promote the operand type to int. 3537 UsualUnaryConversions(Val); 3538 3539 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3540 SourceLocation ExpLoc; 3541 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3542 delete Val; 3543 Val = 0; // Just forget about it. 3544 } else { 3545 EltTy = Val->getType(); 3546 } 3547 } 3548 3549 if (!Val) { 3550 if (LastEnumConst) { 3551 // Assign the last value + 1. 3552 EnumVal = LastEnumConst->getInitVal(); 3553 ++EnumVal; 3554 3555 // Check for overflow on increment. 3556 if (EnumVal < LastEnumConst->getInitVal()) 3557 Diag(IdLoc, diag::warn_enum_value_overflow); 3558 3559 EltTy = LastEnumConst->getType(); 3560 } else { 3561 // First value, set to zero. 3562 EltTy = Context.IntTy; 3563 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3564 } 3565 } 3566 3567 EnumConstantDecl *New = 3568 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3569 Val, EnumVal); 3570 3571 // Register this decl in the current scope stack. 3572 PushOnScopeChains(New, S); 3573 3574 return New; 3575} 3576 3577// FIXME: For consistency with ActOnFields(), we should have the parser 3578// pass in the source location for the left/right braces. 3579void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3580 DeclTy **Elements, unsigned NumElements) { 3581 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3582 QualType EnumType = Context.getTypeDeclType(Enum); 3583 3584 // TODO: If the result value doesn't fit in an int, it must be a long or long 3585 // long value. ISO C does not support this, but GCC does as an extension, 3586 // emit a warning. 3587 unsigned IntWidth = Context.Target.getIntWidth(); 3588 3589 // Verify that all the values are okay, compute the size of the values, and 3590 // reverse the list. 3591 unsigned NumNegativeBits = 0; 3592 unsigned NumPositiveBits = 0; 3593 3594 // Keep track of whether all elements have type int. 3595 bool AllElementsInt = true; 3596 3597 for (unsigned i = 0; i != NumElements; ++i) { 3598 EnumConstantDecl *ECD = 3599 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3600 if (!ECD) continue; // Already issued a diagnostic. 3601 3602 // If the enum value doesn't fit in an int, emit an extension warning. 3603 const llvm::APSInt &InitVal = ECD->getInitVal(); 3604 assert(InitVal.getBitWidth() >= IntWidth && 3605 "Should have promoted value to int"); 3606 if (InitVal.getBitWidth() > IntWidth) { 3607 llvm::APSInt V(InitVal); 3608 V.trunc(IntWidth); 3609 V.extend(InitVal.getBitWidth()); 3610 if (V != InitVal) 3611 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3612 << InitVal.toString(10); 3613 } 3614 3615 // Keep track of the size of positive and negative values. 3616 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3617 NumPositiveBits = std::max(NumPositiveBits, 3618 (unsigned)InitVal.getActiveBits()); 3619 else 3620 NumNegativeBits = std::max(NumNegativeBits, 3621 (unsigned)InitVal.getMinSignedBits()); 3622 3623 // Keep track of whether every enum element has type int (very commmon). 3624 if (AllElementsInt) 3625 AllElementsInt = ECD->getType() == Context.IntTy; 3626 } 3627 3628 // Figure out the type that should be used for this enum. 3629 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3630 QualType BestType; 3631 unsigned BestWidth; 3632 3633 if (NumNegativeBits) { 3634 // If there is a negative value, figure out the smallest integer type (of 3635 // int/long/longlong) that fits. 3636 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3637 BestType = Context.IntTy; 3638 BestWidth = IntWidth; 3639 } else { 3640 BestWidth = Context.Target.getLongWidth(); 3641 3642 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3643 BestType = Context.LongTy; 3644 else { 3645 BestWidth = Context.Target.getLongLongWidth(); 3646 3647 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3648 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3649 BestType = Context.LongLongTy; 3650 } 3651 } 3652 } else { 3653 // If there is no negative value, figure out which of uint, ulong, ulonglong 3654 // fits. 3655 if (NumPositiveBits <= IntWidth) { 3656 BestType = Context.UnsignedIntTy; 3657 BestWidth = IntWidth; 3658 } else if (NumPositiveBits <= 3659 (BestWidth = Context.Target.getLongWidth())) { 3660 BestType = Context.UnsignedLongTy; 3661 } else { 3662 BestWidth = Context.Target.getLongLongWidth(); 3663 assert(NumPositiveBits <= BestWidth && 3664 "How could an initializer get larger than ULL?"); 3665 BestType = Context.UnsignedLongLongTy; 3666 } 3667 } 3668 3669 // Loop over all of the enumerator constants, changing their types to match 3670 // the type of the enum if needed. 3671 for (unsigned i = 0; i != NumElements; ++i) { 3672 EnumConstantDecl *ECD = 3673 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3674 if (!ECD) continue; // Already issued a diagnostic. 3675 3676 // Standard C says the enumerators have int type, but we allow, as an 3677 // extension, the enumerators to be larger than int size. If each 3678 // enumerator value fits in an int, type it as an int, otherwise type it the 3679 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3680 // that X has type 'int', not 'unsigned'. 3681 if (ECD->getType() == Context.IntTy) { 3682 // Make sure the init value is signed. 3683 llvm::APSInt IV = ECD->getInitVal(); 3684 IV.setIsSigned(true); 3685 ECD->setInitVal(IV); 3686 3687 if (getLangOptions().CPlusPlus) 3688 // C++ [dcl.enum]p4: Following the closing brace of an 3689 // enum-specifier, each enumerator has the type of its 3690 // enumeration. 3691 ECD->setType(EnumType); 3692 continue; // Already int type. 3693 } 3694 3695 // Determine whether the value fits into an int. 3696 llvm::APSInt InitVal = ECD->getInitVal(); 3697 bool FitsInInt; 3698 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3699 FitsInInt = InitVal.getActiveBits() < IntWidth; 3700 else 3701 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3702 3703 // If it fits into an integer type, force it. Otherwise force it to match 3704 // the enum decl type. 3705 QualType NewTy; 3706 unsigned NewWidth; 3707 bool NewSign; 3708 if (FitsInInt) { 3709 NewTy = Context.IntTy; 3710 NewWidth = IntWidth; 3711 NewSign = true; 3712 } else if (ECD->getType() == BestType) { 3713 // Already the right type! 3714 if (getLangOptions().CPlusPlus) 3715 // C++ [dcl.enum]p4: Following the closing brace of an 3716 // enum-specifier, each enumerator has the type of its 3717 // enumeration. 3718 ECD->setType(EnumType); 3719 continue; 3720 } else { 3721 NewTy = BestType; 3722 NewWidth = BestWidth; 3723 NewSign = BestType->isSignedIntegerType(); 3724 } 3725 3726 // Adjust the APSInt value. 3727 InitVal.extOrTrunc(NewWidth); 3728 InitVal.setIsSigned(NewSign); 3729 ECD->setInitVal(InitVal); 3730 3731 // Adjust the Expr initializer and type. 3732 if (ECD->getInitExpr()) 3733 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3734 /*isLvalue=*/false)); 3735 if (getLangOptions().CPlusPlus) 3736 // C++ [dcl.enum]p4: Following the closing brace of an 3737 // enum-specifier, each enumerator has the type of its 3738 // enumeration. 3739 ECD->setType(EnumType); 3740 else 3741 ECD->setType(NewTy); 3742 } 3743 3744 Enum->completeDefinition(Context, BestType); 3745} 3746 3747Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3748 ExprArg expr) { 3749 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3750 3751 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3752} 3753 3754 3755void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3756 ExprTy *alignment, SourceLocation PragmaLoc, 3757 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3758 Expr *Alignment = static_cast<Expr *>(alignment); 3759 3760 // If specified then alignment must be a "small" power of two. 3761 unsigned AlignmentVal = 0; 3762 if (Alignment) { 3763 llvm::APSInt Val; 3764 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3765 !Val.isPowerOf2() || 3766 Val.getZExtValue() > 16) { 3767 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3768 delete Alignment; 3769 return; // Ignore 3770 } 3771 3772 AlignmentVal = (unsigned) Val.getZExtValue(); 3773 } 3774 3775 switch (Kind) { 3776 case Action::PPK_Default: // pack([n]) 3777 PackContext.setAlignment(AlignmentVal); 3778 break; 3779 3780 case Action::PPK_Show: // pack(show) 3781 // Show the current alignment, making sure to show the right value 3782 // for the default. 3783 AlignmentVal = PackContext.getAlignment(); 3784 // FIXME: This should come from the target. 3785 if (AlignmentVal == 0) 3786 AlignmentVal = 8; 3787 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3788 break; 3789 3790 case Action::PPK_Push: // pack(push [, id] [, [n]) 3791 PackContext.push(Name); 3792 // Set the new alignment if specified. 3793 if (Alignment) 3794 PackContext.setAlignment(AlignmentVal); 3795 break; 3796 3797 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3798 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3799 // "#pragma pack(pop, identifier, n) is undefined" 3800 if (Alignment && Name) 3801 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3802 3803 // Do the pop. 3804 if (!PackContext.pop(Name)) { 3805 // If a name was specified then failure indicates the name 3806 // wasn't found. Otherwise failure indicates the stack was 3807 // empty. 3808 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3809 << (Name ? "no record matching name" : "stack empty"); 3810 3811 // FIXME: Warn about popping named records as MSVC does. 3812 } else { 3813 // Pop succeeded, set the new alignment if specified. 3814 if (Alignment) 3815 PackContext.setAlignment(AlignmentVal); 3816 } 3817 break; 3818 3819 default: 3820 assert(0 && "Invalid #pragma pack kind."); 3821 } 3822} 3823 3824bool PragmaPackStack::pop(IdentifierInfo *Name) { 3825 if (Stack.empty()) 3826 return false; 3827 3828 // If name is empty just pop top. 3829 if (!Name) { 3830 Alignment = Stack.back().first; 3831 Stack.pop_back(); 3832 return true; 3833 } 3834 3835 // Otherwise, find the named record. 3836 for (unsigned i = Stack.size(); i != 0; ) { 3837 --i; 3838 if (Stack[i].second == Name) { 3839 // Found it, pop up to and including this record. 3840 Alignment = Stack[i].first; 3841 Stack.erase(Stack.begin() + i, Stack.end()); 3842 return true; 3843 } 3844 } 3845 3846 return false; 3847} 3848