SemaDecl.cpp revision a75e8534f2b7c2480c48f31f301bd00b241c5499
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 "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/DeclObjC.h" 20#include "clang/AST/DeclTemplate.h" 21#include "clang/AST/ExprCXX.h" 22#include "clang/AST/StmtCXX.h" 23#include "clang/Parse/DeclSpec.h" 24#include "clang/Basic/TargetInfo.h" 25#include "clang/Basic/SourceManager.h" 26// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 27#include "clang/Lex/Preprocessor.h" 28#include "clang/Lex/HeaderSearch.h" 29#include "llvm/ADT/SmallSet.h" 30#include "llvm/ADT/STLExtras.h" 31#include <algorithm> 32#include <functional> 33using namespace clang; 34 35/// getDeclName - Return a pretty name for the specified decl if possible, or 36/// an empty string if not. This is used for pretty crash reporting. 37std::string Sema::getDeclName(DeclPtrTy d) { 38 Decl *D = d.getAs<Decl>(); 39 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 40 return DN->getQualifiedNameAsString(); 41 return ""; 42} 43 44Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 45 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 46} 47 48/// \brief If the identifier refers to a type name within this scope, 49/// return the declaration of that type. 50/// 51/// This routine performs ordinary name lookup of the identifier II 52/// within the given scope, with optional C++ scope specifier SS, to 53/// determine whether the name refers to a type. If so, returns an 54/// opaque pointer (actually a QualType) corresponding to that 55/// type. Otherwise, returns NULL. 56/// 57/// If name lookup results in an ambiguity, this routine will complain 58/// and then return NULL. 59Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 60 Scope *S, const CXXScopeSpec *SS) { 61 // C++ [temp.res]p3: 62 // A qualified-id that refers to a type and in which the 63 // nested-name-specifier depends on a template-parameter (14.6.2) 64 // shall be prefixed by the keyword typename to indicate that the 65 // qualified-id denotes a type, forming an 66 // elaborated-type-specifier (7.1.5.3). 67 // 68 // We therefore do not perform any name lookup if the result would 69 // refer to a member of an unknown specialization. 70 if (SS && isUnknownSpecialization(*SS)) 71 return 0; 72 73 LookupResult Result 74 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 75 76 NamedDecl *IIDecl = 0; 77 switch (Result.getKind()) { 78 case LookupResult::NotFound: 79 case LookupResult::FoundOverloaded: 80 return 0; 81 82 case LookupResult::AmbiguousBaseSubobjectTypes: 83 case LookupResult::AmbiguousBaseSubobjects: 84 case LookupResult::AmbiguousReference: { 85 // Look to see if we have a type anywhere in the list of results. 86 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 87 Res != ResEnd; ++Res) { 88 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 89 if (!IIDecl || 90 (*Res)->getLocation().getRawEncoding() < 91 IIDecl->getLocation().getRawEncoding()) 92 IIDecl = *Res; 93 } 94 } 95 96 if (!IIDecl) { 97 // None of the entities we found is a type, so there is no way 98 // to even assume that the result is a type. In this case, don't 99 // complain about the ambiguity. The parser will either try to 100 // perform this lookup again (e.g., as an object name), which 101 // will produce the ambiguity, or will complain that it expected 102 // a type name. 103 Result.Destroy(); 104 return 0; 105 } 106 107 // We found a type within the ambiguous lookup; diagnose the 108 // ambiguity and then return that type. This might be the right 109 // answer, or it might not be, but it suppresses any attempt to 110 // perform the name lookup again. 111 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 112 break; 113 } 114 115 case LookupResult::Found: 116 IIDecl = Result.getAsDecl(); 117 break; 118 } 119 120 if (IIDecl) { 121 QualType T; 122 123 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 124 // Check whether we can use this type 125 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 126 127 if (getLangOptions().CPlusPlus) { 128 // C++ [temp.local]p2: 129 // Within the scope of a class template specialization or 130 // partial specialization, when the injected-class-name is 131 // not followed by a <, it is equivalent to the 132 // injected-class-name followed by the template-argument s 133 // of the class template specialization or partial 134 // specialization enclosed in <>. 135 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 136 if (RD->isInjectedClassName()) 137 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 138 T = Template->getInjectedClassNameType(Context); 139 } 140 141 if (T.isNull()) 142 T = Context.getTypeDeclType(TD); 143 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 144 // Check whether we can use this interface. 145 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 146 147 T = Context.getObjCInterfaceType(IDecl); 148 } else 149 return 0; 150 151 if (SS) 152 T = getQualifiedNameType(*SS, T); 153 154 return T.getAsOpaquePtr(); 155 } 156 157 return 0; 158} 159 160/// isTagName() - This method is called *for error recovery purposes only* 161/// to determine if the specified name is a valid tag name ("struct foo"). If 162/// so, this returns the TST for the tag corresponding to it (TST_enum, 163/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 164/// where the user forgot to specify the tag. 165DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 166 // Do a tag name lookup in this scope. 167 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 168 if (R.getKind() == LookupResult::Found) 169 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 170 switch (TD->getTagKind()) { 171 case TagDecl::TK_struct: return DeclSpec::TST_struct; 172 case TagDecl::TK_union: return DeclSpec::TST_union; 173 case TagDecl::TK_class: return DeclSpec::TST_class; 174 case TagDecl::TK_enum: return DeclSpec::TST_enum; 175 } 176 } 177 178 return DeclSpec::TST_unspecified; 179} 180 181 182 183DeclContext *Sema::getContainingDC(DeclContext *DC) { 184 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 185 // A C++ out-of-line method will return to the file declaration context. 186 if (MD->isOutOfLineDefinition()) 187 return MD->getLexicalDeclContext(); 188 189 // A C++ inline method is parsed *after* the topmost class it was declared 190 // in is fully parsed (it's "complete"). 191 // The parsing of a C++ inline method happens at the declaration context of 192 // the topmost (non-nested) class it is lexically declared in. 193 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 194 DC = MD->getParent(); 195 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 196 DC = RD; 197 198 // Return the declaration context of the topmost class the inline method is 199 // declared in. 200 return DC; 201 } 202 203 if (isa<ObjCMethodDecl>(DC)) 204 return Context.getTranslationUnitDecl(); 205 206 return DC->getLexicalParent(); 207} 208 209void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 210 assert(getContainingDC(DC) == CurContext && 211 "The next DeclContext should be lexically contained in the current one."); 212 CurContext = DC; 213 S->setEntity(DC); 214} 215 216void Sema::PopDeclContext() { 217 assert(CurContext && "DeclContext imbalance!"); 218 219 CurContext = getContainingDC(CurContext); 220} 221 222/// \brief Determine whether we allow overloading of the function 223/// PrevDecl with another declaration. 224/// 225/// This routine determines whether overloading is possible, not 226/// whether some new function is actually an overload. It will return 227/// true in C++ (where we can always provide overloads) or, as an 228/// extension, in C when the previous function is already an 229/// overloaded function declaration or has the "overloadable" 230/// attribute. 231static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 232 if (Context.getLangOptions().CPlusPlus) 233 return true; 234 235 if (isa<OverloadedFunctionDecl>(PrevDecl)) 236 return true; 237 238 return PrevDecl->getAttr<OverloadableAttr>() != 0; 239} 240 241/// Add this decl to the scope shadowed decl chains. 242void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 243 // Move up the scope chain until we find the nearest enclosing 244 // non-transparent context. The declaration will be introduced into this 245 // scope. 246 while (S->getEntity() && 247 ((DeclContext *)S->getEntity())->isTransparentContext()) 248 S = S->getParent(); 249 250 S->AddDecl(DeclPtrTy::make(D)); 251 252 // Add scoped declarations into their context, so that they can be 253 // found later. Declarations without a context won't be inserted 254 // into any context. 255 CurContext->addDecl(Context, D); 256 257 // C++ [basic.scope]p4: 258 // -- exactly one declaration shall declare a class name or 259 // enumeration name that is not a typedef name and the other 260 // declarations shall all refer to the same object or 261 // enumerator, or all refer to functions and function templates; 262 // in this case the class name or enumeration name is hidden. 263 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 264 // We are pushing the name of a tag (enum or class). 265 if (CurContext->getLookupContext() 266 == TD->getDeclContext()->getLookupContext()) { 267 // We're pushing the tag into the current context, which might 268 // require some reshuffling in the identifier resolver. 269 IdentifierResolver::iterator 270 I = IdResolver.begin(TD->getDeclName()), 271 IEnd = IdResolver.end(); 272 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 273 NamedDecl *PrevDecl = *I; 274 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 275 PrevDecl = *I, ++I) { 276 if (TD->declarationReplaces(*I)) { 277 // This is a redeclaration. Remove it from the chain and 278 // break out, so that we'll add in the shadowed 279 // declaration. 280 S->RemoveDecl(DeclPtrTy::make(*I)); 281 if (PrevDecl == *I) { 282 IdResolver.RemoveDecl(*I); 283 IdResolver.AddDecl(TD); 284 return; 285 } else { 286 IdResolver.RemoveDecl(*I); 287 break; 288 } 289 } 290 } 291 292 // There is already a declaration with the same name in the same 293 // scope, which is not a tag declaration. It must be found 294 // before we find the new declaration, so insert the new 295 // declaration at the end of the chain. 296 IdResolver.AddShadowedDecl(TD, PrevDecl); 297 298 return; 299 } 300 } 301 } else if (isa<FunctionDecl>(D) && 302 AllowOverloadingOfFunction(D, Context)) { 303 // We are pushing the name of a function, which might be an 304 // overloaded name. 305 FunctionDecl *FD = cast<FunctionDecl>(D); 306 IdentifierResolver::iterator Redecl 307 = std::find_if(IdResolver.begin(FD->getDeclName()), 308 IdResolver.end(), 309 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 310 FD)); 311 if (Redecl != IdResolver.end() && 312 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 313 // There is already a declaration of a function on our 314 // IdResolver chain. Replace it with this declaration. 315 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 316 IdResolver.RemoveDecl(*Redecl); 317 } 318 } else if (isa<ObjCInterfaceDecl>(D)) { 319 // We're pushing an Objective-C interface into the current 320 // context. If there is already an alias declaration, remove it first. 321 for (IdentifierResolver::iterator 322 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 323 I != IEnd; ++I) { 324 if (isa<ObjCCompatibleAliasDecl>(*I)) { 325 S->RemoveDecl(DeclPtrTy::make(*I)); 326 IdResolver.RemoveDecl(*I); 327 break; 328 } 329 } 330 } 331 332 IdResolver.AddDecl(D); 333} 334 335void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 336 if (S->decl_empty()) return; 337 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 338 "Scope shouldn't contain decls!"); 339 340 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 341 I != E; ++I) { 342 Decl *TmpD = (*I).getAs<Decl>(); 343 assert(TmpD && "This decl didn't get pushed??"); 344 345 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 346 NamedDecl *D = cast<NamedDecl>(TmpD); 347 348 if (!D->getDeclName()) continue; 349 350 // Remove this name from our lexical scope. 351 IdResolver.RemoveDecl(D); 352 } 353} 354 355/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 356/// return 0 if one not found. 357ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 358 // The third "scope" argument is 0 since we aren't enabling lazy built-in 359 // creation from this context. 360 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 361 362 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 363} 364 365/// getNonFieldDeclScope - Retrieves the innermost scope, starting 366/// from S, where a non-field would be declared. This routine copes 367/// with the difference between C and C++ scoping rules in structs and 368/// unions. For example, the following code is well-formed in C but 369/// ill-formed in C++: 370/// @code 371/// struct S6 { 372/// enum { BAR } e; 373/// }; 374/// 375/// void test_S6() { 376/// struct S6 a; 377/// a.e = BAR; 378/// } 379/// @endcode 380/// For the declaration of BAR, this routine will return a different 381/// scope. The scope S will be the scope of the unnamed enumeration 382/// within S6. In C++, this routine will return the scope associated 383/// with S6, because the enumeration's scope is a transparent 384/// context but structures can contain non-field names. In C, this 385/// routine will return the translation unit scope, since the 386/// enumeration's scope is a transparent context and structures cannot 387/// contain non-field names. 388Scope *Sema::getNonFieldDeclScope(Scope *S) { 389 while (((S->getFlags() & Scope::DeclScope) == 0) || 390 (S->getEntity() && 391 ((DeclContext *)S->getEntity())->isTransparentContext()) || 392 (S->isClassScope() && !getLangOptions().CPlusPlus)) 393 S = S->getParent(); 394 return S; 395} 396 397void Sema::InitBuiltinVaListType() { 398 if (!Context.getBuiltinVaListType().isNull()) 399 return; 400 401 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 402 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 403 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 404 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 405} 406 407/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 408/// file scope. lazily create a decl for it. ForRedeclaration is true 409/// if we're creating this built-in in anticipation of redeclaring the 410/// built-in. 411NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 412 Scope *S, bool ForRedeclaration, 413 SourceLocation Loc) { 414 Builtin::ID BID = (Builtin::ID)bid; 415 416 if (Context.BuiltinInfo.hasVAListUse(BID)) 417 InitBuiltinVaListType(); 418 419 Builtin::Context::GetBuiltinTypeError Error; 420 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 421 switch (Error) { 422 case Builtin::Context::GE_None: 423 // Okay 424 break; 425 426 case Builtin::Context::GE_Missing_FILE: 427 if (ForRedeclaration) 428 Diag(Loc, diag::err_implicit_decl_requires_stdio) 429 << Context.BuiltinInfo.GetName(BID); 430 return 0; 431 } 432 433 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 434 Diag(Loc, diag::ext_implicit_lib_function_decl) 435 << Context.BuiltinInfo.GetName(BID) 436 << R; 437 if (Context.BuiltinInfo.getHeaderName(BID) && 438 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 439 != Diagnostic::Ignored) 440 Diag(Loc, diag::note_please_include_header) 441 << Context.BuiltinInfo.getHeaderName(BID) 442 << Context.BuiltinInfo.GetName(BID); 443 } 444 445 FunctionDecl *New = FunctionDecl::Create(Context, 446 Context.getTranslationUnitDecl(), 447 Loc, II, R, 448 FunctionDecl::Extern, false, 449 /*hasPrototype=*/true); 450 New->setImplicit(); 451 452 // Create Decl objects for each parameter, adding them to the 453 // FunctionDecl. 454 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 455 llvm::SmallVector<ParmVarDecl*, 16> Params; 456 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 457 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 458 FT->getArgType(i), VarDecl::None, 0)); 459 New->setParams(Context, &Params[0], Params.size()); 460 } 461 462 AddKnownFunctionAttributes(New); 463 464 // TUScope is the translation-unit scope to insert this function into. 465 // FIXME: This is hideous. We need to teach PushOnScopeChains to 466 // relate Scopes to DeclContexts, and probably eliminate CurContext 467 // entirely, but we're not there yet. 468 DeclContext *SavedContext = CurContext; 469 CurContext = Context.getTranslationUnitDecl(); 470 PushOnScopeChains(New, TUScope); 471 CurContext = SavedContext; 472 return New; 473} 474 475/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 476/// everything from the standard library is defined. 477NamespaceDecl *Sema::GetStdNamespace() { 478 if (!StdNamespace) { 479 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 480 DeclContext *Global = Context.getTranslationUnitDecl(); 481 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 482 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 483 } 484 return StdNamespace; 485} 486 487/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 488/// same name and scope as a previous declaration 'Old'. Figure out 489/// how to resolve this situation, merging decls or emitting 490/// diagnostics as appropriate. If there was an error, set New to be invalid. 491/// 492void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 493 // If either decl is known invalid already, set the new one to be invalid and 494 // don't bother doing any merging checks. 495 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 496 return New->setInvalidDecl(); 497 498 bool objc_types = false; 499 500 // Allow multiple definitions for ObjC built-in typedefs. 501 // FIXME: Verify the underlying types are equivalent! 502 if (getLangOptions().ObjC1) { 503 const IdentifierInfo *TypeID = New->getIdentifier(); 504 switch (TypeID->getLength()) { 505 default: break; 506 case 2: 507 if (!TypeID->isStr("id")) 508 break; 509 Context.setObjCIdType(Context.getTypeDeclType(New)); 510 objc_types = true; 511 break; 512 case 5: 513 if (!TypeID->isStr("Class")) 514 break; 515 Context.setObjCClassType(Context.getTypeDeclType(New)); 516 return; 517 case 3: 518 if (!TypeID->isStr("SEL")) 519 break; 520 Context.setObjCSelType(Context.getTypeDeclType(New)); 521 return; 522 case 8: 523 if (!TypeID->isStr("Protocol")) 524 break; 525 Context.setObjCProtoType(New->getUnderlyingType()); 526 return; 527 } 528 // Fall through - the typedef name was not a builtin type. 529 } 530 // Verify the old decl was also a type. 531 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 532 if (!Old) { 533 Diag(New->getLocation(), diag::err_redefinition_different_kind) 534 << New->getDeclName(); 535 if (OldD->getLocation().isValid()) 536 Diag(OldD->getLocation(), diag::note_previous_definition); 537 return New->setInvalidDecl(); 538 } 539 540 // Determine the "old" type we'll use for checking and diagnostics. 541 QualType OldType; 542 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 543 OldType = OldTypedef->getUnderlyingType(); 544 else 545 OldType = Context.getTypeDeclType(Old); 546 547 // If the typedef types are not identical, reject them in all languages and 548 // with any extensions enabled. 549 550 if (OldType != New->getUnderlyingType() && 551 Context.getCanonicalType(OldType) != 552 Context.getCanonicalType(New->getUnderlyingType())) { 553 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 554 << New->getUnderlyingType() << OldType; 555 if (Old->getLocation().isValid()) 556 Diag(Old->getLocation(), diag::note_previous_definition); 557 return New->setInvalidDecl(); 558 } 559 560 if (objc_types || getLangOptions().Microsoft) 561 return; 562 563 // C++ [dcl.typedef]p2: 564 // In a given non-class scope, a typedef specifier can be used to 565 // redefine the name of any type declared in that scope to refer 566 // to the type to which it already refers. 567 if (getLangOptions().CPlusPlus) { 568 if (!isa<CXXRecordDecl>(CurContext)) 569 return; 570 Diag(New->getLocation(), diag::err_redefinition) 571 << New->getDeclName(); 572 Diag(Old->getLocation(), diag::note_previous_definition); 573 return New->setInvalidDecl(); 574 } 575 576 // If we have a redefinition of a typedef in C, emit a warning. This warning 577 // is normally mapped to an error, but can be controlled with 578 // -Wtypedef-redefinition. If either the original was in a system header, 579 // don't emit this for compatibility with GCC. 580 if (PP.getDiagnostics().getSuppressSystemWarnings() && 581 Context.getSourceManager().isInSystemHeader(Old->getLocation())) 582 return; 583 584 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 585 << New->getDeclName(); 586 Diag(Old->getLocation(), diag::note_previous_definition); 587 return; 588} 589 590/// DeclhasAttr - returns true if decl Declaration already has the target 591/// attribute. 592static bool DeclHasAttr(const Decl *decl, const Attr *target) { 593 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 594 if (attr->getKind() == target->getKind()) 595 return true; 596 597 return false; 598} 599 600/// MergeAttributes - append attributes from the Old decl to the New one. 601static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 602 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 603 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 604 Attr *NewAttr = attr->clone(C); 605 NewAttr->setInherited(true); 606 New->addAttr(NewAttr); 607 } 608 } 609} 610 611/// Used in MergeFunctionDecl to keep track of function parameters in 612/// C. 613struct GNUCompatibleParamWarning { 614 ParmVarDecl *OldParm; 615 ParmVarDecl *NewParm; 616 QualType PromotedType; 617}; 618 619/// MergeFunctionDecl - We just parsed a function 'New' from 620/// declarator D which has the same name and scope as a previous 621/// declaration 'Old'. Figure out how to resolve this situation, 622/// merging decls or emitting diagnostics as appropriate. 623/// 624/// In C++, New and Old must be declarations that are not 625/// overloaded. Use IsOverload to determine whether New and Old are 626/// overloaded, and to select the Old declaration that New should be 627/// merged with. 628/// 629/// Returns true if there was an error, false otherwise. 630bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 631 assert(!isa<OverloadedFunctionDecl>(OldD) && 632 "Cannot merge with an overloaded function declaration"); 633 634 // Verify the old decl was also a function. 635 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 636 if (!Old) { 637 Diag(New->getLocation(), diag::err_redefinition_different_kind) 638 << New->getDeclName(); 639 Diag(OldD->getLocation(), diag::note_previous_definition); 640 return true; 641 } 642 643 // Determine whether the previous declaration was a definition, 644 // implicit declaration, or a declaration. 645 diag::kind PrevDiag; 646 if (Old->isThisDeclarationADefinition()) 647 PrevDiag = diag::note_previous_definition; 648 else if (Old->isImplicit()) 649 PrevDiag = diag::note_previous_implicit_declaration; 650 else 651 PrevDiag = diag::note_previous_declaration; 652 653 QualType OldQType = Context.getCanonicalType(Old->getType()); 654 QualType NewQType = Context.getCanonicalType(New->getType()); 655 656 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 657 New->getStorageClass() == FunctionDecl::Static && 658 Old->getStorageClass() != FunctionDecl::Static) { 659 Diag(New->getLocation(), diag::err_static_non_static) 660 << New; 661 Diag(Old->getLocation(), PrevDiag); 662 return true; 663 } 664 665 if (getLangOptions().CPlusPlus) { 666 // (C++98 13.1p2): 667 // Certain function declarations cannot be overloaded: 668 // -- Function declarations that differ only in the return type 669 // cannot be overloaded. 670 QualType OldReturnType 671 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 672 QualType NewReturnType 673 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 674 if (OldReturnType != NewReturnType) { 675 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 676 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 677 return true; 678 } 679 680 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 681 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 682 if (OldMethod && NewMethod && 683 OldMethod->getLexicalDeclContext() == 684 NewMethod->getLexicalDeclContext()) { 685 // -- Member function declarations with the same name and the 686 // same parameter types cannot be overloaded if any of them 687 // is a static member function declaration. 688 if (OldMethod->isStatic() || NewMethod->isStatic()) { 689 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 690 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 691 return true; 692 } 693 694 // C++ [class.mem]p1: 695 // [...] A member shall not be declared twice in the 696 // member-specification, except that a nested class or member 697 // class template can be declared and then later defined. 698 unsigned NewDiag; 699 if (isa<CXXConstructorDecl>(OldMethod)) 700 NewDiag = diag::err_constructor_redeclared; 701 else if (isa<CXXDestructorDecl>(NewMethod)) 702 NewDiag = diag::err_destructor_redeclared; 703 else if (isa<CXXConversionDecl>(NewMethod)) 704 NewDiag = diag::err_conv_function_redeclared; 705 else 706 NewDiag = diag::err_member_redeclared; 707 708 Diag(New->getLocation(), NewDiag); 709 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 710 } 711 712 // (C++98 8.3.5p3): 713 // All declarations for a function shall agree exactly in both the 714 // return type and the parameter-type-list. 715 if (OldQType == NewQType) 716 return MergeCompatibleFunctionDecls(New, Old); 717 718 // Fall through for conflicting redeclarations and redefinitions. 719 } 720 721 // C: Function types need to be compatible, not identical. This handles 722 // duplicate function decls like "void f(int); void f(enum X);" properly. 723 if (!getLangOptions().CPlusPlus && 724 Context.typesAreCompatible(OldQType, NewQType)) { 725 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 726 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 727 const FunctionProtoType *OldProto = 0; 728 if (isa<FunctionNoProtoType>(NewFuncType) && 729 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 730 // The old declaration provided a function prototype, but the 731 // new declaration does not. Merge in the prototype. 732 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 733 OldProto->arg_type_end()); 734 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 735 &ParamTypes[0], ParamTypes.size(), 736 OldProto->isVariadic(), 737 OldProto->getTypeQuals()); 738 New->setType(NewQType); 739 New->setHasInheritedPrototype(); 740 741 // Synthesize a parameter for each argument type. 742 llvm::SmallVector<ParmVarDecl*, 16> Params; 743 for (FunctionProtoType::arg_type_iterator 744 ParamType = OldProto->arg_type_begin(), 745 ParamEnd = OldProto->arg_type_end(); 746 ParamType != ParamEnd; ++ParamType) { 747 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 748 SourceLocation(), 0, 749 *ParamType, VarDecl::None, 750 0); 751 Param->setImplicit(); 752 Params.push_back(Param); 753 } 754 755 New->setParams(Context, &Params[0], Params.size()); 756 } 757 758 return MergeCompatibleFunctionDecls(New, Old); 759 } 760 761 // GNU C permits a K&R definition to follow a prototype declaration 762 // if the declared types of the parameters in the K&R definition 763 // match the types in the prototype declaration, even when the 764 // promoted types of the parameters from the K&R definition differ 765 // from the types in the prototype. GCC then keeps the types from 766 // the prototype. 767 if (!getLangOptions().CPlusPlus && 768 Old->hasPrototype() && !New->hasPrototype() && 769 New->getType()->getAsFunctionProtoType() && 770 Old->getNumParams() == New->getNumParams()) { 771 llvm::SmallVector<QualType, 16> ArgTypes; 772 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 773 const FunctionProtoType *OldProto 774 = Old->getType()->getAsFunctionProtoType(); 775 const FunctionProtoType *NewProto 776 = New->getType()->getAsFunctionProtoType(); 777 778 // Determine whether this is the GNU C extension. 779 bool GNUCompatible = 780 Context.typesAreCompatible(OldProto->getResultType(), 781 NewProto->getResultType()) && 782 (OldProto->isVariadic() == NewProto->isVariadic()); 783 for (unsigned Idx = 0, End = Old->getNumParams(); 784 GNUCompatible && Idx != End; ++Idx) { 785 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 786 ParmVarDecl *NewParm = New->getParamDecl(Idx); 787 if (Context.typesAreCompatible(OldParm->getType(), 788 NewProto->getArgType(Idx))) { 789 ArgTypes.push_back(NewParm->getType()); 790 } else if (Context.typesAreCompatible(OldParm->getType(), 791 NewParm->getType())) { 792 GNUCompatibleParamWarning Warn 793 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 794 Warnings.push_back(Warn); 795 ArgTypes.push_back(NewParm->getType()); 796 } else 797 GNUCompatible = false; 798 } 799 800 if (GNUCompatible) { 801 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 802 Diag(Warnings[Warn].NewParm->getLocation(), 803 diag::ext_param_promoted_not_compatible_with_prototype) 804 << Warnings[Warn].PromotedType 805 << Warnings[Warn].OldParm->getType(); 806 Diag(Warnings[Warn].OldParm->getLocation(), 807 diag::note_previous_declaration); 808 } 809 810 New->setType(Context.getFunctionType(NewProto->getResultType(), 811 &ArgTypes[0], ArgTypes.size(), 812 NewProto->isVariadic(), 813 NewProto->getTypeQuals())); 814 return MergeCompatibleFunctionDecls(New, Old); 815 } 816 817 // Fall through to diagnose conflicting types. 818 } 819 820 // A function that has already been declared has been redeclared or defined 821 // with a different type- show appropriate diagnostic 822 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 823 // The user has declared a builtin function with an incompatible 824 // signature. 825 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 826 // The function the user is redeclaring is a library-defined 827 // function like 'malloc' or 'printf'. Warn about the 828 // redeclaration, then pretend that we don't know about this 829 // library built-in. 830 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 831 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 832 << Old << Old->getType(); 833 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 834 Old->setInvalidDecl(); 835 return false; 836 } 837 838 PrevDiag = diag::note_previous_builtin_declaration; 839 } 840 841 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 842 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 843 return true; 844} 845 846/// \brief Completes the merge of two function declarations that are 847/// known to be compatible. 848/// 849/// This routine handles the merging of attributes and other 850/// properties of function declarations form the old declaration to 851/// the new declaration, once we know that New is in fact a 852/// redeclaration of Old. 853/// 854/// \returns false 855bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 856 // Merge the attributes 857 MergeAttributes(New, Old, Context); 858 859 // Merge the storage class. 860 if (Old->getStorageClass() != FunctionDecl::Extern) 861 New->setStorageClass(Old->getStorageClass()); 862 863 // Merge "inline" 864 if (Old->isInline()) 865 New->setInline(true); 866 867 // If this function declaration by itself qualifies as a C99 inline 868 // definition (C99 6.7.4p6), but the previous definition did not, 869 // then the function is not a C99 inline definition. 870 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 871 New->setC99InlineDefinition(false); 872 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 873 // Mark all preceding definitions as not being C99 inline definitions. 874 for (const FunctionDecl *Prev = Old; Prev; 875 Prev = Prev->getPreviousDeclaration()) 876 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 877 } 878 879 // Merge "pure" flag. 880 if (Old->isPure()) 881 New->setPure(); 882 883 // Merge the "deleted" flag. 884 if (Old->isDeleted()) 885 New->setDeleted(); 886 887 if (getLangOptions().CPlusPlus) 888 return MergeCXXFunctionDecl(New, Old); 889 890 return false; 891} 892 893/// MergeVarDecl - We just parsed a variable 'New' which has the same name 894/// and scope as a previous declaration 'Old'. Figure out how to resolve this 895/// situation, merging decls or emitting diagnostics as appropriate. 896/// 897/// Tentative definition rules (C99 6.9.2p2) are checked by 898/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 899/// definitions here, since the initializer hasn't been attached. 900/// 901void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 902 // If either decl is invalid, make sure the new one is marked invalid and 903 // don't do any other checking. 904 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 905 return New->setInvalidDecl(); 906 907 // Verify the old decl was also a variable. 908 VarDecl *Old = dyn_cast<VarDecl>(OldD); 909 if (!Old) { 910 Diag(New->getLocation(), diag::err_redefinition_different_kind) 911 << New->getDeclName(); 912 Diag(OldD->getLocation(), diag::note_previous_definition); 913 return New->setInvalidDecl(); 914 } 915 916 MergeAttributes(New, Old, Context); 917 918 // Merge the types 919 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 920 if (MergedT.isNull()) { 921 Diag(New->getLocation(), diag::err_redefinition_different_type) 922 << New->getDeclName(); 923 Diag(Old->getLocation(), diag::note_previous_definition); 924 return New->setInvalidDecl(); 925 } 926 New->setType(MergedT); 927 928 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 929 if (New->getStorageClass() == VarDecl::Static && 930 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 931 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 932 Diag(Old->getLocation(), diag::note_previous_definition); 933 return New->setInvalidDecl(); 934 } 935 // C99 6.2.2p4: 936 // For an identifier declared with the storage-class specifier 937 // extern in a scope in which a prior declaration of that 938 // identifier is visible,23) if the prior declaration specifies 939 // internal or external linkage, the linkage of the identifier at 940 // the later declaration is the same as the linkage specified at 941 // the prior declaration. If no prior declaration is visible, or 942 // if the prior declaration specifies no linkage, then the 943 // identifier has external linkage. 944 if (New->hasExternalStorage() && Old->hasLinkage()) 945 /* Okay */; 946 else if (New->getStorageClass() != VarDecl::Static && 947 Old->getStorageClass() == VarDecl::Static) { 948 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 949 Diag(Old->getLocation(), diag::note_previous_definition); 950 return New->setInvalidDecl(); 951 } 952 953 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 954 955 // FIXME: The test for external storage here seems wrong? We still 956 // need to check for mismatches. 957 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 958 // Don't complain about out-of-line definitions of static members. 959 !(Old->getLexicalDeclContext()->isRecord() && 960 !New->getLexicalDeclContext()->isRecord())) { 961 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 962 Diag(Old->getLocation(), diag::note_previous_definition); 963 return New->setInvalidDecl(); 964 } 965 966 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 967 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 968 Diag(Old->getLocation(), diag::note_previous_definition); 969 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 970 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 971 Diag(Old->getLocation(), diag::note_previous_definition); 972 } 973 974 // Keep a chain of previous declarations. 975 New->setPreviousDeclaration(Old); 976} 977 978/// CheckParmsForFunctionDef - Check that the parameters of the given 979/// function are appropriate for the definition of a function. This 980/// takes care of any checks that cannot be performed on the 981/// declaration itself, e.g., that the types of each of the function 982/// parameters are complete. 983bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 984 bool HasInvalidParm = false; 985 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 986 ParmVarDecl *Param = FD->getParamDecl(p); 987 988 // C99 6.7.5.3p4: the parameters in a parameter type list in a 989 // function declarator that is part of a function definition of 990 // that function shall not have incomplete type. 991 // 992 // This is also C++ [dcl.fct]p6. 993 if (!Param->isInvalidDecl() && 994 RequireCompleteType(Param->getLocation(), Param->getType(), 995 diag::err_typecheck_decl_incomplete_type)) { 996 Param->setInvalidDecl(); 997 HasInvalidParm = true; 998 } 999 1000 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1001 // declaration of each parameter shall include an identifier. 1002 if (Param->getIdentifier() == 0 && 1003 !Param->isImplicit() && 1004 !getLangOptions().CPlusPlus) 1005 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1006 } 1007 1008 return HasInvalidParm; 1009} 1010 1011/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1012/// no declarator (e.g. "struct foo;") is parsed. 1013Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1014 // FIXME: Error on auto/register at file scope 1015 // FIXME: Error on inline/virtual/explicit 1016 // FIXME: Error on invalid restrict 1017 // FIXME: Warn on useless __thread 1018 // FIXME: Warn on useless const/volatile 1019 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1020 // FIXME: Warn on useless attributes 1021 TagDecl *Tag = 0; 1022 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1023 DS.getTypeSpecType() == DeclSpec::TST_struct || 1024 DS.getTypeSpecType() == DeclSpec::TST_union || 1025 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1026 if (!DS.getTypeRep()) // We probably had an error 1027 return DeclPtrTy(); 1028 1029 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1030 } 1031 1032 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1033 if (!Record->getDeclName() && Record->isDefinition() && 1034 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1035 if (getLangOptions().CPlusPlus || 1036 Record->getDeclContext()->isRecord()) 1037 return BuildAnonymousStructOrUnion(S, DS, Record); 1038 1039 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1040 << DS.getSourceRange(); 1041 } 1042 1043 // Microsoft allows unnamed struct/union fields. Don't complain 1044 // about them. 1045 // FIXME: Should we support Microsoft's extensions in this area? 1046 if (Record->getDeclName() && getLangOptions().Microsoft) 1047 return DeclPtrTy::make(Tag); 1048 } 1049 1050 if (!DS.isMissingDeclaratorOk() && 1051 DS.getTypeSpecType() != DeclSpec::TST_error) { 1052 // Warn about typedefs of enums without names, since this is an 1053 // extension in both Microsoft an GNU. 1054 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1055 Tag && isa<EnumDecl>(Tag)) { 1056 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1057 << DS.getSourceRange(); 1058 return DeclPtrTy::make(Tag); 1059 } 1060 1061 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1062 << DS.getSourceRange(); 1063 return DeclPtrTy(); 1064 } 1065 1066 return DeclPtrTy::make(Tag); 1067} 1068 1069/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1070/// anonymous struct or union AnonRecord into the owning context Owner 1071/// and scope S. This routine will be invoked just after we realize 1072/// that an unnamed union or struct is actually an anonymous union or 1073/// struct, e.g., 1074/// 1075/// @code 1076/// union { 1077/// int i; 1078/// float f; 1079/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1080/// // f into the surrounding scope.x 1081/// @endcode 1082/// 1083/// This routine is recursive, injecting the names of nested anonymous 1084/// structs/unions into the owning context and scope as well. 1085bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1086 RecordDecl *AnonRecord) { 1087 bool Invalid = false; 1088 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1089 FEnd = AnonRecord->field_end(Context); 1090 F != FEnd; ++F) { 1091 if ((*F)->getDeclName()) { 1092 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1093 LookupOrdinaryName, true); 1094 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1095 // C++ [class.union]p2: 1096 // The names of the members of an anonymous union shall be 1097 // distinct from the names of any other entity in the 1098 // scope in which the anonymous union is declared. 1099 unsigned diagKind 1100 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1101 : diag::err_anonymous_struct_member_redecl; 1102 Diag((*F)->getLocation(), diagKind) 1103 << (*F)->getDeclName(); 1104 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1105 Invalid = true; 1106 } else { 1107 // C++ [class.union]p2: 1108 // For the purpose of name lookup, after the anonymous union 1109 // definition, the members of the anonymous union are 1110 // considered to have been defined in the scope in which the 1111 // anonymous union is declared. 1112 Owner->makeDeclVisibleInContext(Context, *F); 1113 S->AddDecl(DeclPtrTy::make(*F)); 1114 IdResolver.AddDecl(*F); 1115 } 1116 } else if (const RecordType *InnerRecordType 1117 = (*F)->getType()->getAsRecordType()) { 1118 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1119 if (InnerRecord->isAnonymousStructOrUnion()) 1120 Invalid = Invalid || 1121 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1122 } 1123 } 1124 1125 return Invalid; 1126} 1127 1128/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1129/// anonymous structure or union. Anonymous unions are a C++ feature 1130/// (C++ [class.union]) and a GNU C extension; anonymous structures 1131/// are a GNU C and GNU C++ extension. 1132Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1133 RecordDecl *Record) { 1134 DeclContext *Owner = Record->getDeclContext(); 1135 1136 // Diagnose whether this anonymous struct/union is an extension. 1137 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1138 Diag(Record->getLocation(), diag::ext_anonymous_union); 1139 else if (!Record->isUnion()) 1140 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1141 1142 // C and C++ require different kinds of checks for anonymous 1143 // structs/unions. 1144 bool Invalid = false; 1145 if (getLangOptions().CPlusPlus) { 1146 const char* PrevSpec = 0; 1147 // C++ [class.union]p3: 1148 // Anonymous unions declared in a named namespace or in the 1149 // global namespace shall be declared static. 1150 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1151 (isa<TranslationUnitDecl>(Owner) || 1152 (isa<NamespaceDecl>(Owner) && 1153 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1154 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1155 Invalid = true; 1156 1157 // Recover by adding 'static'. 1158 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1159 } 1160 // C++ [class.union]p3: 1161 // A storage class is not allowed in a declaration of an 1162 // anonymous union in a class scope. 1163 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1164 isa<RecordDecl>(Owner)) { 1165 Diag(DS.getStorageClassSpecLoc(), 1166 diag::err_anonymous_union_with_storage_spec); 1167 Invalid = true; 1168 1169 // Recover by removing the storage specifier. 1170 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1171 PrevSpec); 1172 } 1173 1174 // C++ [class.union]p2: 1175 // The member-specification of an anonymous union shall only 1176 // define non-static data members. [Note: nested types and 1177 // functions cannot be declared within an anonymous union. ] 1178 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1179 MemEnd = Record->decls_end(Context); 1180 Mem != MemEnd; ++Mem) { 1181 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1182 // C++ [class.union]p3: 1183 // An anonymous union shall not have private or protected 1184 // members (clause 11). 1185 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1186 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1187 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1188 Invalid = true; 1189 } 1190 } else if ((*Mem)->isImplicit()) { 1191 // Any implicit members are fine. 1192 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1193 // This is a type that showed up in an 1194 // elaborated-type-specifier inside the anonymous struct or 1195 // union, but which actually declares a type outside of the 1196 // anonymous struct or union. It's okay. 1197 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1198 if (!MemRecord->isAnonymousStructOrUnion() && 1199 MemRecord->getDeclName()) { 1200 // This is a nested type declaration. 1201 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1202 << (int)Record->isUnion(); 1203 Invalid = true; 1204 } 1205 } else { 1206 // We have something that isn't a non-static data 1207 // member. Complain about it. 1208 unsigned DK = diag::err_anonymous_record_bad_member; 1209 if (isa<TypeDecl>(*Mem)) 1210 DK = diag::err_anonymous_record_with_type; 1211 else if (isa<FunctionDecl>(*Mem)) 1212 DK = diag::err_anonymous_record_with_function; 1213 else if (isa<VarDecl>(*Mem)) 1214 DK = diag::err_anonymous_record_with_static; 1215 Diag((*Mem)->getLocation(), DK) 1216 << (int)Record->isUnion(); 1217 Invalid = true; 1218 } 1219 } 1220 } 1221 1222 if (!Record->isUnion() && !Owner->isRecord()) { 1223 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1224 << (int)getLangOptions().CPlusPlus; 1225 Invalid = true; 1226 } 1227 1228 // Create a declaration for this anonymous struct/union. 1229 NamedDecl *Anon = 0; 1230 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1231 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1232 /*IdentifierInfo=*/0, 1233 Context.getTypeDeclType(Record), 1234 /*BitWidth=*/0, /*Mutable=*/false); 1235 Anon->setAccess(AS_public); 1236 if (getLangOptions().CPlusPlus) 1237 FieldCollector->Add(cast<FieldDecl>(Anon)); 1238 } else { 1239 VarDecl::StorageClass SC; 1240 switch (DS.getStorageClassSpec()) { 1241 default: assert(0 && "Unknown storage class!"); 1242 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1243 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1244 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1245 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1246 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1247 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1248 case DeclSpec::SCS_mutable: 1249 // mutable can only appear on non-static class members, so it's always 1250 // an error here 1251 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1252 Invalid = true; 1253 SC = VarDecl::None; 1254 break; 1255 } 1256 1257 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1258 /*IdentifierInfo=*/0, 1259 Context.getTypeDeclType(Record), 1260 SC, DS.getSourceRange().getBegin()); 1261 } 1262 Anon->setImplicit(); 1263 1264 // Add the anonymous struct/union object to the current 1265 // context. We'll be referencing this object when we refer to one of 1266 // its members. 1267 Owner->addDecl(Context, Anon); 1268 1269 // Inject the members of the anonymous struct/union into the owning 1270 // context and into the identifier resolver chain for name lookup 1271 // purposes. 1272 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1273 Invalid = true; 1274 1275 // Mark this as an anonymous struct/union type. Note that we do not 1276 // do this until after we have already checked and injected the 1277 // members of this anonymous struct/union type, because otherwise 1278 // the members could be injected twice: once by DeclContext when it 1279 // builds its lookup table, and once by 1280 // InjectAnonymousStructOrUnionMembers. 1281 Record->setAnonymousStructOrUnion(true); 1282 1283 if (Invalid) 1284 Anon->setInvalidDecl(); 1285 1286 return DeclPtrTy::make(Anon); 1287} 1288 1289 1290/// GetNameForDeclarator - Determine the full declaration name for the 1291/// given Declarator. 1292DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1293 switch (D.getKind()) { 1294 case Declarator::DK_Abstract: 1295 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1296 return DeclarationName(); 1297 1298 case Declarator::DK_Normal: 1299 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1300 return DeclarationName(D.getIdentifier()); 1301 1302 case Declarator::DK_Constructor: { 1303 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1304 Ty = Context.getCanonicalType(Ty); 1305 return Context.DeclarationNames.getCXXConstructorName(Ty); 1306 } 1307 1308 case Declarator::DK_Destructor: { 1309 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1310 Ty = Context.getCanonicalType(Ty); 1311 return Context.DeclarationNames.getCXXDestructorName(Ty); 1312 } 1313 1314 case Declarator::DK_Conversion: { 1315 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1316 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1317 Ty = Context.getCanonicalType(Ty); 1318 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1319 } 1320 1321 case Declarator::DK_Operator: 1322 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1323 return Context.DeclarationNames.getCXXOperatorName( 1324 D.getOverloadedOperator()); 1325 } 1326 1327 assert(false && "Unknown name kind"); 1328 return DeclarationName(); 1329} 1330 1331/// isNearlyMatchingFunction - Determine whether the C++ functions 1332/// Declaration and Definition are "nearly" matching. This heuristic 1333/// is used to improve diagnostics in the case where an out-of-line 1334/// function definition doesn't match any declaration within 1335/// the class or namespace. 1336static bool isNearlyMatchingFunction(ASTContext &Context, 1337 FunctionDecl *Declaration, 1338 FunctionDecl *Definition) { 1339 if (Declaration->param_size() != Definition->param_size()) 1340 return false; 1341 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1342 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1343 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1344 1345 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1346 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1347 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1348 return false; 1349 } 1350 1351 return true; 1352} 1353 1354Sema::DeclPtrTy 1355Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1356 DeclarationName Name = GetNameForDeclarator(D); 1357 1358 // All of these full declarators require an identifier. If it doesn't have 1359 // one, the ParsedFreeStandingDeclSpec action should be used. 1360 if (!Name) { 1361 if (!D.isInvalidType()) // Reject this if we think it is valid. 1362 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1363 diag::err_declarator_need_ident) 1364 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1365 return DeclPtrTy(); 1366 } 1367 1368 // The scope passed in may not be a decl scope. Zip up the scope tree until 1369 // we find one that is. 1370 while ((S->getFlags() & Scope::DeclScope) == 0 || 1371 (S->getFlags() & Scope::TemplateParamScope) != 0) 1372 S = S->getParent(); 1373 1374 DeclContext *DC; 1375 NamedDecl *PrevDecl; 1376 NamedDecl *New; 1377 1378 QualType R = GetTypeForDeclarator(D, S); 1379 1380 // See if this is a redefinition of a variable in the same scope. 1381 if (D.getCXXScopeSpec().isInvalid()) { 1382 DC = CurContext; 1383 PrevDecl = 0; 1384 D.setInvalidType(); 1385 } else if (!D.getCXXScopeSpec().isSet()) { 1386 LookupNameKind NameKind = LookupOrdinaryName; 1387 1388 // If the declaration we're planning to build will be a function 1389 // or object with linkage, then look for another declaration with 1390 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1391 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1392 /* Do nothing*/; 1393 else if (R->isFunctionType()) { 1394 if (CurContext->isFunctionOrMethod()) 1395 NameKind = LookupRedeclarationWithLinkage; 1396 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1397 NameKind = LookupRedeclarationWithLinkage; 1398 1399 DC = CurContext; 1400 PrevDecl = LookupName(S, Name, NameKind, true, 1401 D.getDeclSpec().getStorageClassSpec() != 1402 DeclSpec::SCS_static, 1403 D.getIdentifierLoc()); 1404 } else { // Something like "int foo::x;" 1405 DC = computeDeclContext(D.getCXXScopeSpec()); 1406 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1407 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1408 1409 // C++ 7.3.1.2p2: 1410 // Members (including explicit specializations of templates) of a named 1411 // namespace can also be defined outside that namespace by explicit 1412 // qualification of the name being defined, provided that the entity being 1413 // defined was already declared in the namespace and the definition appears 1414 // after the point of declaration in a namespace that encloses the 1415 // declarations namespace. 1416 // 1417 // Note that we only check the context at this point. We don't yet 1418 // have enough information to make sure that PrevDecl is actually 1419 // the declaration we want to match. For example, given: 1420 // 1421 // class X { 1422 // void f(); 1423 // void f(float); 1424 // }; 1425 // 1426 // void X::f(int) { } // ill-formed 1427 // 1428 // In this case, PrevDecl will point to the overload set 1429 // containing the two f's declared in X, but neither of them 1430 // matches. 1431 1432 // First check whether we named the global scope. 1433 if (isa<TranslationUnitDecl>(DC)) { 1434 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1435 << Name << D.getCXXScopeSpec().getRange(); 1436 } else if (!CurContext->Encloses(DC)) { 1437 // The qualifying scope doesn't enclose the original declaration. 1438 // Emit diagnostic based on current scope. 1439 SourceLocation L = D.getIdentifierLoc(); 1440 SourceRange R = D.getCXXScopeSpec().getRange(); 1441 if (isa<FunctionDecl>(CurContext)) 1442 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1443 else 1444 Diag(L, diag::err_invalid_declarator_scope) 1445 << Name << cast<NamedDecl>(DC) << R; 1446 D.setInvalidType(); 1447 } 1448 } 1449 1450 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1451 // Maybe we will complain about the shadowed template parameter. 1452 if (!D.isInvalidType()) 1453 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1454 D.setInvalidType(); 1455 1456 // Just pretend that we didn't see the previous declaration. 1457 PrevDecl = 0; 1458 } 1459 1460 // In C++, the previous declaration we find might be a tag type 1461 // (class or enum). In this case, the new declaration will hide the 1462 // tag type. Note that this does does not apply if we're declaring a 1463 // typedef (C++ [dcl.typedef]p4). 1464 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1465 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1466 PrevDecl = 0; 1467 1468 bool Redeclaration = false; 1469 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1470 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1471 } else if (R->isFunctionType()) { 1472 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1473 IsFunctionDefinition, Redeclaration); 1474 } else { 1475 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1476 } 1477 1478 if (New == 0) 1479 return DeclPtrTy(); 1480 1481 // If this has an identifier and is not an invalid redeclaration, 1482 // add it to the scope stack. 1483 if (Name && !(Redeclaration && New->isInvalidDecl())) 1484 PushOnScopeChains(New, S); 1485 1486 return DeclPtrTy::make(New); 1487} 1488 1489/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1490/// types into constant array types in certain situations which would otherwise 1491/// be errors (for GCC compatibility). 1492static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1493 ASTContext &Context, 1494 bool &SizeIsNegative) { 1495 // This method tries to turn a variable array into a constant 1496 // array even when the size isn't an ICE. This is necessary 1497 // for compatibility with code that depends on gcc's buggy 1498 // constant expression folding, like struct {char x[(int)(char*)2];} 1499 SizeIsNegative = false; 1500 1501 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1502 QualType Pointee = PTy->getPointeeType(); 1503 QualType FixedType = 1504 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1505 if (FixedType.isNull()) return FixedType; 1506 FixedType = Context.getPointerType(FixedType); 1507 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1508 return FixedType; 1509 } 1510 1511 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1512 if (!VLATy) 1513 return QualType(); 1514 // FIXME: We should probably handle this case 1515 if (VLATy->getElementType()->isVariablyModifiedType()) 1516 return QualType(); 1517 1518 Expr::EvalResult EvalResult; 1519 if (!VLATy->getSizeExpr() || 1520 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1521 !EvalResult.Val.isInt()) 1522 return QualType(); 1523 1524 llvm::APSInt &Res = EvalResult.Val.getInt(); 1525 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1526 return Context.getConstantArrayType(VLATy->getElementType(), 1527 Res, ArrayType::Normal, 0); 1528 1529 SizeIsNegative = true; 1530 return QualType(); 1531} 1532 1533/// \brief Register the given locally-scoped external C declaration so 1534/// that it can be found later for redeclarations 1535void 1536Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1537 Scope *S) { 1538 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1539 "Decl is not a locally-scoped decl!"); 1540 // Note that we have a locally-scoped external with this name. 1541 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1542 1543 if (!PrevDecl) 1544 return; 1545 1546 // If there was a previous declaration of this variable, it may be 1547 // in our identifier chain. Update the identifier chain with the new 1548 // declaration. 1549 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1550 // The previous declaration was found on the identifer resolver 1551 // chain, so remove it from its scope. 1552 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1553 S = S->getParent(); 1554 1555 if (S) 1556 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1557 } 1558} 1559 1560/// \brief Diagnose function specifiers on a declaration of an identifier that 1561/// does not identify a function. 1562void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1563 // FIXME: We should probably indicate the identifier in question to avoid 1564 // confusion for constructs like "inline int a(), b;" 1565 if (D.getDeclSpec().isInlineSpecified()) 1566 Diag(D.getDeclSpec().getInlineSpecLoc(), 1567 diag::err_inline_non_function); 1568 1569 if (D.getDeclSpec().isVirtualSpecified()) 1570 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1571 diag::err_virtual_non_function); 1572 1573 if (D.getDeclSpec().isExplicitSpecified()) 1574 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1575 diag::err_explicit_non_function); 1576} 1577 1578NamedDecl* 1579Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1580 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1581 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1582 if (D.getCXXScopeSpec().isSet()) { 1583 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1584 << D.getCXXScopeSpec().getRange(); 1585 D.setInvalidType(); 1586 // Pretend we didn't see the scope specifier. 1587 DC = 0; 1588 } 1589 1590 if (getLangOptions().CPlusPlus) { 1591 // Check that there are no default arguments (C++ only). 1592 CheckExtraCXXDefaultArguments(D); 1593 } 1594 1595 DiagnoseFunctionSpecifiers(D); 1596 1597 if (D.getDeclSpec().isThreadSpecified()) 1598 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1599 1600 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1601 if (!NewTD) return 0; 1602 1603 if (D.isInvalidType()) 1604 NewTD->setInvalidDecl(); 1605 1606 // Handle attributes prior to checking for duplicates in MergeVarDecl 1607 ProcessDeclAttributes(NewTD, D); 1608 // Merge the decl with the existing one if appropriate. If the decl is 1609 // in an outer scope, it isn't the same thing. 1610 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1611 Redeclaration = true; 1612 MergeTypeDefDecl(NewTD, PrevDecl); 1613 } 1614 1615 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1616 // then it shall have block scope. 1617 QualType T = NewTD->getUnderlyingType(); 1618 if (T->isVariablyModifiedType()) { 1619 CurFunctionNeedsScopeChecking = true; 1620 1621 if (S->getFnParent() == 0) { 1622 bool SizeIsNegative; 1623 QualType FixedTy = 1624 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1625 if (!FixedTy.isNull()) { 1626 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1627 NewTD->setUnderlyingType(FixedTy); 1628 } else { 1629 if (SizeIsNegative) 1630 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1631 else if (T->isVariableArrayType()) 1632 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1633 else 1634 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1635 NewTD->setInvalidDecl(); 1636 } 1637 } 1638 } 1639 return NewTD; 1640} 1641 1642/// \brief Determines whether the given declaration is an out-of-scope 1643/// previous declaration. 1644/// 1645/// This routine should be invoked when name lookup has found a 1646/// previous declaration (PrevDecl) that is not in the scope where a 1647/// new declaration by the same name is being introduced. If the new 1648/// declaration occurs in a local scope, previous declarations with 1649/// linkage may still be considered previous declarations (C99 1650/// 6.2.2p4-5, C++ [basic.link]p6). 1651/// 1652/// \param PrevDecl the previous declaration found by name 1653/// lookup 1654/// 1655/// \param DC the context in which the new declaration is being 1656/// declared. 1657/// 1658/// \returns true if PrevDecl is an out-of-scope previous declaration 1659/// for a new delcaration with the same name. 1660static bool 1661isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1662 ASTContext &Context) { 1663 if (!PrevDecl) 1664 return 0; 1665 1666 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1667 // case we need to check each of the overloaded functions. 1668 if (!PrevDecl->hasLinkage()) 1669 return false; 1670 1671 if (Context.getLangOptions().CPlusPlus) { 1672 // C++ [basic.link]p6: 1673 // If there is a visible declaration of an entity with linkage 1674 // having the same name and type, ignoring entities declared 1675 // outside the innermost enclosing namespace scope, the block 1676 // scope declaration declares that same entity and receives the 1677 // linkage of the previous declaration. 1678 DeclContext *OuterContext = DC->getLookupContext(); 1679 if (!OuterContext->isFunctionOrMethod()) 1680 // This rule only applies to block-scope declarations. 1681 return false; 1682 else { 1683 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1684 if (PrevOuterContext->isRecord()) 1685 // We found a member function: ignore it. 1686 return false; 1687 else { 1688 // Find the innermost enclosing namespace for the new and 1689 // previous declarations. 1690 while (!OuterContext->isFileContext()) 1691 OuterContext = OuterContext->getParent(); 1692 while (!PrevOuterContext->isFileContext()) 1693 PrevOuterContext = PrevOuterContext->getParent(); 1694 1695 // The previous declaration is in a different namespace, so it 1696 // isn't the same function. 1697 if (OuterContext->getPrimaryContext() != 1698 PrevOuterContext->getPrimaryContext()) 1699 return false; 1700 } 1701 } 1702 } 1703 1704 return true; 1705} 1706 1707NamedDecl* 1708Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1709 QualType R,NamedDecl* PrevDecl, 1710 bool &Redeclaration) { 1711 DeclarationName Name = GetNameForDeclarator(D); 1712 1713 // Check that there are no default arguments (C++ only). 1714 if (getLangOptions().CPlusPlus) 1715 CheckExtraCXXDefaultArguments(D); 1716 1717 VarDecl *NewVD; 1718 VarDecl::StorageClass SC; 1719 switch (D.getDeclSpec().getStorageClassSpec()) { 1720 default: assert(0 && "Unknown storage class!"); 1721 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1722 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1723 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1724 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1725 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1726 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1727 case DeclSpec::SCS_mutable: 1728 // mutable can only appear on non-static class members, so it's always 1729 // an error here 1730 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1731 D.setInvalidType(); 1732 SC = VarDecl::None; 1733 break; 1734 } 1735 1736 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1737 if (!II) { 1738 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1739 << Name.getAsString(); 1740 return 0; 1741 } 1742 1743 DiagnoseFunctionSpecifiers(D); 1744 1745 if (!DC->isRecord() && S->getFnParent() == 0) { 1746 // C99 6.9p2: The storage-class specifiers auto and register shall not 1747 // appear in the declaration specifiers in an external declaration. 1748 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1749 1750 // If this is a register variable with an asm label specified, then this 1751 // is a GNU extension. 1752 if (SC == VarDecl::Register && D.getAsmLabel()) 1753 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1754 else 1755 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1756 D.setInvalidType(); 1757 } 1758 } 1759 if (DC->isRecord() && !CurContext->isRecord()) { 1760 // This is an out-of-line definition of a static data member. 1761 if (SC == VarDecl::Static) { 1762 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1763 diag::err_static_out_of_line) 1764 << CodeModificationHint::CreateRemoval( 1765 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1766 } else if (SC == VarDecl::None) 1767 SC = VarDecl::Static; 1768 } 1769 1770 // The variable can not 1771 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1772 II, R, SC, 1773 // FIXME: Move to DeclGroup... 1774 D.getDeclSpec().getSourceRange().getBegin()); 1775 1776 if (D.isInvalidType()) 1777 NewVD->setInvalidDecl(); 1778 1779 if (D.getDeclSpec().isThreadSpecified()) { 1780 if (NewVD->hasLocalStorage()) 1781 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1782 else if (!Context.Target.isTLSSupported()) 1783 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1784 else 1785 NewVD->setThreadSpecified(true); 1786 } 1787 1788 // Set the lexical context. If the declarator has a C++ scope specifier, the 1789 // lexical context will be different from the semantic context. 1790 NewVD->setLexicalDeclContext(CurContext); 1791 1792 // Handle attributes prior to checking for duplicates in MergeVarDecl 1793 ProcessDeclAttributes(NewVD, D); 1794 1795 // Handle GNU asm-label extension (encoded as an attribute). 1796 if (Expr *E = (Expr*) D.getAsmLabel()) { 1797 // The parser guarantees this is a string. 1798 StringLiteral *SE = cast<StringLiteral>(E); 1799 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1800 SE->getByteLength()))); 1801 } 1802 1803 // If name lookup finds a previous declaration that is not in the 1804 // same scope as the new declaration, this may still be an 1805 // acceptable redeclaration. 1806 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1807 !(NewVD->hasLinkage() && 1808 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1809 PrevDecl = 0; 1810 1811 // Merge the decl with the existing one if appropriate. 1812 if (PrevDecl) { 1813 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1814 // The user tried to define a non-static data member 1815 // out-of-line (C++ [dcl.meaning]p1). 1816 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1817 << D.getCXXScopeSpec().getRange(); 1818 PrevDecl = 0; 1819 NewVD->setInvalidDecl(); 1820 } 1821 } else if (D.getCXXScopeSpec().isSet()) { 1822 // No previous declaration in the qualifying scope. 1823 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1824 << Name << D.getCXXScopeSpec().getRange(); 1825 NewVD->setInvalidDecl(); 1826 } 1827 1828 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1829 1830 // If this is a locally-scoped extern C variable, update the map of 1831 // such variables. 1832 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1833 !NewVD->isInvalidDecl()) 1834 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1835 1836 return NewVD; 1837} 1838 1839/// \brief Perform semantic checking on a newly-created variable 1840/// declaration. 1841/// 1842/// This routine performs all of the type-checking required for a 1843/// variable declaration once it has been built. It is used both to 1844/// check variables after they have been parsed and their declarators 1845/// have been translated into a declaration, and to check variables 1846/// that have been instantiated from a template. 1847/// 1848/// Sets NewVD->isInvalidDecl() if an error was encountered. 1849void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1850 bool &Redeclaration) { 1851 // If the decl is already known invalid, don't check it. 1852 if (NewVD->isInvalidDecl()) 1853 return; 1854 1855 QualType T = NewVD->getType(); 1856 1857 if (T->isObjCInterfaceType()) { 1858 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1859 return NewVD->setInvalidDecl(); 1860 } 1861 1862 // The variable can not have an abstract class type. 1863 if (RequireNonAbstractType(NewVD->getLocation(), T, 1864 diag::err_abstract_type_in_decl, 1865 AbstractVariableType)) 1866 return NewVD->setInvalidDecl(); 1867 1868 // Emit an error if an address space was applied to decl with local storage. 1869 // This includes arrays of objects with address space qualifiers, but not 1870 // automatic variables that point to other address spaces. 1871 // ISO/IEC TR 18037 S5.1.2 1872 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1873 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1874 return NewVD->setInvalidDecl(); 1875 } 1876 1877 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1878 && !NewVD->hasAttr<BlocksAttr>()) 1879 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1880 1881 bool isVM = T->isVariablyModifiedType(); 1882 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1883 CurFunctionNeedsScopeChecking = true; 1884 1885 if ((isVM && NewVD->hasLinkage()) || 1886 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1887 bool SizeIsNegative; 1888 QualType FixedTy = 1889 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1890 1891 if (FixedTy.isNull() && T->isVariableArrayType()) { 1892 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1893 // FIXME: This won't give the correct result for 1894 // int a[10][n]; 1895 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1896 1897 if (NewVD->isFileVarDecl()) 1898 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1899 << SizeRange; 1900 else if (NewVD->getStorageClass() == VarDecl::Static) 1901 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1902 << SizeRange; 1903 else 1904 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1905 << SizeRange; 1906 return NewVD->setInvalidDecl(); 1907 } 1908 1909 if (FixedTy.isNull()) { 1910 if (NewVD->isFileVarDecl()) 1911 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1912 else 1913 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1914 return NewVD->setInvalidDecl(); 1915 } 1916 1917 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1918 NewVD->setType(FixedTy); 1919 } 1920 1921 if (!PrevDecl && NewVD->isExternC(Context)) { 1922 // Since we did not find anything by this name and we're declaring 1923 // an extern "C" variable, look for a non-visible extern "C" 1924 // declaration with the same name. 1925 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1926 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1927 if (Pos != LocallyScopedExternalDecls.end()) 1928 PrevDecl = Pos->second; 1929 } 1930 1931 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1932 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1933 << T; 1934 return NewVD->setInvalidDecl(); 1935 } 1936 1937 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 1938 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 1939 return NewVD->setInvalidDecl(); 1940 } 1941 1942 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 1943 Diag(NewVD->getLocation(), diag::err_block_on_vm); 1944 return NewVD->setInvalidDecl(); 1945 } 1946 1947 if (PrevDecl) { 1948 Redeclaration = true; 1949 MergeVarDecl(NewVD, PrevDecl); 1950 } 1951} 1952 1953NamedDecl* 1954Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1955 QualType R, NamedDecl* PrevDecl, 1956 bool IsFunctionDefinition, bool &Redeclaration) { 1957 assert(R.getTypePtr()->isFunctionType()); 1958 1959 DeclarationName Name = GetNameForDeclarator(D); 1960 FunctionDecl::StorageClass SC = FunctionDecl::None; 1961 switch (D.getDeclSpec().getStorageClassSpec()) { 1962 default: assert(0 && "Unknown storage class!"); 1963 case DeclSpec::SCS_auto: 1964 case DeclSpec::SCS_register: 1965 case DeclSpec::SCS_mutable: 1966 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1967 diag::err_typecheck_sclass_func); 1968 D.setInvalidType(); 1969 break; 1970 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1971 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1972 case DeclSpec::SCS_static: { 1973 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1974 // C99 6.7.1p5: 1975 // The declaration of an identifier for a function that has 1976 // block scope shall have no explicit storage-class specifier 1977 // other than extern 1978 // See also (C++ [dcl.stc]p4). 1979 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1980 diag::err_static_block_func); 1981 SC = FunctionDecl::None; 1982 } else 1983 SC = FunctionDecl::Static; 1984 break; 1985 } 1986 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1987 } 1988 1989 if (D.getDeclSpec().isThreadSpecified()) 1990 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1991 1992 bool isInline = D.getDeclSpec().isInlineSpecified(); 1993 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1994 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1995 1996 // Check that the return type is not an abstract class type. 1997 // For record types, this is done by the AbstractClassUsageDiagnoser once 1998 // the class has been completely parsed. 1999 if (!DC->isRecord() && 2000 RequireNonAbstractType(D.getIdentifierLoc(), 2001 R->getAsFunctionType()->getResultType(), 2002 diag::err_abstract_type_in_decl, 2003 AbstractReturnType)) 2004 D.setInvalidType(); 2005 2006 // Do not allow returning a objc interface by-value. 2007 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2008 Diag(D.getIdentifierLoc(), 2009 diag::err_object_cannot_be_passed_returned_by_value) << 0 2010 << R->getAsFunctionType()->getResultType(); 2011 D.setInvalidType(); 2012 } 2013 2014 bool isVirtualOkay = false; 2015 FunctionDecl *NewFD; 2016 if (D.getKind() == Declarator::DK_Constructor) { 2017 // This is a C++ constructor declaration. 2018 assert(DC->isRecord() && 2019 "Constructors can only be declared in a member context"); 2020 2021 R = CheckConstructorDeclarator(D, R, SC); 2022 2023 // Create the new declaration 2024 NewFD = CXXConstructorDecl::Create(Context, 2025 cast<CXXRecordDecl>(DC), 2026 D.getIdentifierLoc(), Name, R, 2027 isExplicit, isInline, 2028 /*isImplicitlyDeclared=*/false); 2029 } else if (D.getKind() == Declarator::DK_Destructor) { 2030 // This is a C++ destructor declaration. 2031 if (DC->isRecord()) { 2032 R = CheckDestructorDeclarator(D, SC); 2033 2034 NewFD = CXXDestructorDecl::Create(Context, 2035 cast<CXXRecordDecl>(DC), 2036 D.getIdentifierLoc(), Name, R, 2037 isInline, 2038 /*isImplicitlyDeclared=*/false); 2039 2040 isVirtualOkay = true; 2041 } else { 2042 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2043 2044 // Create a FunctionDecl to satisfy the function definition parsing 2045 // code path. 2046 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2047 Name, R, SC, isInline, 2048 /*hasPrototype=*/true, 2049 // FIXME: Move to DeclGroup... 2050 D.getDeclSpec().getSourceRange().getBegin()); 2051 D.setInvalidType(); 2052 } 2053 } else if (D.getKind() == Declarator::DK_Conversion) { 2054 if (!DC->isRecord()) { 2055 Diag(D.getIdentifierLoc(), 2056 diag::err_conv_function_not_member); 2057 return 0; 2058 } 2059 2060 CheckConversionDeclarator(D, R, SC); 2061 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2062 D.getIdentifierLoc(), Name, R, 2063 isInline, isExplicit); 2064 2065 isVirtualOkay = true; 2066 } else if (DC->isRecord()) { 2067 // If the of the function is the same as the name of the record, then this 2068 // must be an invalid constructor that has a return type. 2069 // (The parser checks for a return type and makes the declarator a 2070 // constructor if it has no return type). 2071 // must have an invalid constructor that has a return type 2072 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2073 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2074 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2075 << SourceRange(D.getIdentifierLoc()); 2076 return 0; 2077 } 2078 2079 // This is a C++ method declaration. 2080 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2081 D.getIdentifierLoc(), Name, R, 2082 (SC == FunctionDecl::Static), isInline); 2083 2084 isVirtualOkay = (SC != FunctionDecl::Static); 2085 } else { 2086 // Determine whether the function was written with a 2087 // prototype. This true when: 2088 // - we're in C++ (where every function has a prototype), 2089 // - there is a prototype in the declarator, or 2090 // - the type R of the function is some kind of typedef or other reference 2091 // to a type name (which eventually refers to a function type). 2092 bool HasPrototype = 2093 getLangOptions().CPlusPlus || 2094 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2095 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2096 2097 NewFD = FunctionDecl::Create(Context, DC, 2098 D.getIdentifierLoc(), 2099 Name, R, SC, isInline, HasPrototype, 2100 // FIXME: Move to DeclGroup... 2101 D.getDeclSpec().getSourceRange().getBegin()); 2102 } 2103 2104 if (D.isInvalidType()) 2105 NewFD->setInvalidDecl(); 2106 2107 // Set the lexical context. If the declarator has a C++ 2108 // scope specifier, the lexical context will be different 2109 // from the semantic context. 2110 NewFD->setLexicalDeclContext(CurContext); 2111 2112 // C++ [dcl.fct.spec]p5: 2113 // The virtual specifier shall only be used in declarations of 2114 // nonstatic class member functions that appear within a 2115 // member-specification of a class declaration; see 10.3. 2116 // 2117 if (isVirtual && !NewFD->isInvalidDecl()) { 2118 if (!isVirtualOkay) { 2119 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2120 diag::err_virtual_non_function); 2121 } else if (!CurContext->isRecord()) { 2122 // 'virtual' was specified outside of the class. 2123 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2124 << CodeModificationHint::CreateRemoval( 2125 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2126 } else { 2127 // Okay: Add virtual to the method. 2128 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2129 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2130 CurClass->setAggregate(false); 2131 CurClass->setPOD(false); 2132 CurClass->setPolymorphic(true); 2133 CurClass->setHasTrivialConstructor(false); 2134 } 2135 } 2136 2137 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2138 // Look for virtual methods in base classes that this method might override. 2139 2140 BasePaths Paths; 2141 // FIXME: This will not include hidden member functions. 2142 if (LookupInBases(cast<CXXRecordDecl>(DC), 2143 MemberLookupCriteria(Name, LookupMemberName, 2144 // FIXME: Shouldn't IDNS_Member be 2145 // enough here? 2146 Decl::IDNS_Member | 2147 Decl::IDNS_Ordinary), Paths)) { 2148 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2149 E = Paths.found_decls_end(); I != E; ++I) { 2150 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2151 OverloadedFunctionDecl::function_iterator MatchedDecl; 2152 // FIXME: Is this OK? Should it be done by LookupInBases? 2153 if (IsOverload(NewMD, OldMD, MatchedDecl)) 2154 continue; 2155 2156 if (!CheckOverridingFunctionReturnType(NewMD, OldMD)) { 2157 // FIXME: Add OldMD to the list of methods NewMD overrides. 2158 } 2159 2160 } 2161 } 2162 2163 } 2164 2165 } 2166 2167 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2168 !CurContext->isRecord()) { 2169 // C++ [class.static]p1: 2170 // A data or function member of a class may be declared static 2171 // in a class definition, in which case it is a static member of 2172 // the class. 2173 2174 // Complain about the 'static' specifier if it's on an out-of-line 2175 // member function definition. 2176 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2177 diag::err_static_out_of_line) 2178 << CodeModificationHint::CreateRemoval( 2179 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2180 } 2181 2182 // Handle GNU asm-label extension (encoded as an attribute). 2183 if (Expr *E = (Expr*) D.getAsmLabel()) { 2184 // The parser guarantees this is a string. 2185 StringLiteral *SE = cast<StringLiteral>(E); 2186 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2187 SE->getByteLength()))); 2188 } 2189 2190 // Copy the parameter declarations from the declarator D to the function 2191 // declaration NewFD, if they are available. First scavenge them into Params. 2192 llvm::SmallVector<ParmVarDecl*, 16> Params; 2193 if (D.getNumTypeObjects() > 0) { 2194 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2195 2196 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2197 // function that takes no arguments, not a function that takes a 2198 // single void argument. 2199 // We let through "const void" here because Sema::GetTypeForDeclarator 2200 // already checks for that case. 2201 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2202 FTI.ArgInfo[0].Param && 2203 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2204 // Empty arg list, don't push any params. 2205 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2206 2207 // In C++, the empty parameter-type-list must be spelled "void"; a 2208 // typedef of void is not permitted. 2209 if (getLangOptions().CPlusPlus && 2210 Param->getType().getUnqualifiedType() != Context.VoidTy) 2211 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2212 // FIXME: Leaks decl? 2213 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2214 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2215 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2216 } 2217 2218 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2219 // When we're declaring a function with a typedef, typeof, etc as in the 2220 // following example, we'll need to synthesize (unnamed) 2221 // parameters for use in the declaration. 2222 // 2223 // @code 2224 // typedef void fn(int); 2225 // fn f; 2226 // @endcode 2227 2228 // Synthesize a parameter for each argument type. 2229 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2230 AE = FT->arg_type_end(); AI != AE; ++AI) { 2231 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2232 SourceLocation(), 0, 2233 *AI, VarDecl::None, 0); 2234 Param->setImplicit(); 2235 Params.push_back(Param); 2236 } 2237 } else { 2238 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2239 "Should not need args for typedef of non-prototype fn"); 2240 } 2241 // Finally, we know we have the right number of parameters, install them. 2242 NewFD->setParams(Context, &Params[0], Params.size()); 2243 2244 2245 2246 // If name lookup finds a previous declaration that is not in the 2247 // same scope as the new declaration, this may still be an 2248 // acceptable redeclaration. 2249 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2250 !(NewFD->hasLinkage() && 2251 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2252 PrevDecl = 0; 2253 2254 // Perform semantic checking on the function declaration. 2255 bool OverloadableAttrRequired = false; // FIXME: HACK! 2256 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2257 /*FIXME:*/OverloadableAttrRequired); 2258 2259 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2260 // An out-of-line member function declaration must also be a 2261 // definition (C++ [dcl.meaning]p1). 2262 if (!IsFunctionDefinition) { 2263 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2264 << D.getCXXScopeSpec().getRange(); 2265 NewFD->setInvalidDecl(); 2266 } else if (!Redeclaration) { 2267 // The user tried to provide an out-of-line definition for a 2268 // function that is a member of a class or namespace, but there 2269 // was no such member function declared (C++ [class.mfct]p2, 2270 // C++ [namespace.memdef]p2). For example: 2271 // 2272 // class X { 2273 // void f() const; 2274 // }; 2275 // 2276 // void X::f() { } // ill-formed 2277 // 2278 // Complain about this problem, and attempt to suggest close 2279 // matches (e.g., those that differ only in cv-qualifiers and 2280 // whether the parameter types are references). 2281 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2282 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2283 NewFD->setInvalidDecl(); 2284 2285 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2286 true); 2287 assert(!Prev.isAmbiguous() && 2288 "Cannot have an ambiguity in previous-declaration lookup"); 2289 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2290 Func != FuncEnd; ++Func) { 2291 if (isa<FunctionDecl>(*Func) && 2292 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2293 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2294 } 2295 2296 PrevDecl = 0; 2297 } 2298 } 2299 2300 // Handle attributes. We need to have merged decls when handling attributes 2301 // (for example to check for conflicts, etc). 2302 // FIXME: This needs to happen before we merge declarations. Then, 2303 // let attribute merging cope with attribute conflicts. 2304 ProcessDeclAttributes(NewFD, D); 2305 AddKnownFunctionAttributes(NewFD); 2306 2307 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2308 // If a function name is overloadable in C, then every function 2309 // with that name must be marked "overloadable". 2310 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2311 << Redeclaration << NewFD; 2312 if (PrevDecl) 2313 Diag(PrevDecl->getLocation(), 2314 diag::note_attribute_overloadable_prev_overload); 2315 NewFD->addAttr(::new (Context) OverloadableAttr()); 2316 } 2317 2318 // If this is a locally-scoped extern C function, update the 2319 // map of such names. 2320 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2321 && !NewFD->isInvalidDecl()) 2322 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2323 2324 return NewFD; 2325} 2326 2327/// \brief Perform semantic checking of a new function declaration. 2328/// 2329/// Performs semantic analysis of the new function declaration 2330/// NewFD. This routine performs all semantic checking that does not 2331/// require the actual declarator involved in the declaration, and is 2332/// used both for the declaration of functions as they are parsed 2333/// (called via ActOnDeclarator) and for the declaration of functions 2334/// that have been instantiated via C++ template instantiation (called 2335/// via InstantiateDecl). 2336/// 2337/// This sets NewFD->isInvalidDecl() to true if there was an error. 2338void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2339 bool &Redeclaration, 2340 bool &OverloadableAttrRequired) { 2341 // If NewFD is already known erroneous, don't do any of this checking. 2342 if (NewFD->isInvalidDecl()) 2343 return; 2344 2345 // Semantic checking for this function declaration (in isolation). 2346 if (getLangOptions().CPlusPlus) { 2347 // C++-specific checks. 2348 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2349 CheckConstructor(Constructor); 2350 } else if (isa<CXXDestructorDecl>(NewFD)) { 2351 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2352 Record->setUserDeclaredDestructor(true); 2353 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2354 // user-defined destructor. 2355 Record->setPOD(false); 2356 2357 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2358 // declared destructor. 2359 Record->setHasTrivialDestructor(false); 2360 } else if (CXXConversionDecl *Conversion 2361 = dyn_cast<CXXConversionDecl>(NewFD)) 2362 ActOnConversionDeclarator(Conversion); 2363 2364 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2365 if (NewFD->isOverloadedOperator() && 2366 CheckOverloadedOperatorDeclaration(NewFD)) 2367 return NewFD->setInvalidDecl(); 2368 } 2369 2370 // C99 6.7.4p6: 2371 // [... ] For a function with external linkage, the following 2372 // restrictions apply: [...] If all of the file scope declarations 2373 // for a function in a translation unit include the inline 2374 // function specifier without extern, then the definition in that 2375 // translation unit is an inline definition. An inline definition 2376 // does not provide an external definition for the function, and 2377 // does not forbid an external definition in another translation 2378 // unit. 2379 // 2380 // Here we determine whether this function, in isolation, would be a 2381 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2382 // previous declarations. 2383 if (NewFD->isInline() && getLangOptions().C99 && 2384 NewFD->getStorageClass() == FunctionDecl::None && 2385 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2386 NewFD->setC99InlineDefinition(true); 2387 2388 // Check for a previous declaration of this name. 2389 if (!PrevDecl && NewFD->isExternC(Context)) { 2390 // Since we did not find anything by this name and we're declaring 2391 // an extern "C" function, look for a non-visible extern "C" 2392 // declaration with the same name. 2393 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2394 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2395 if (Pos != LocallyScopedExternalDecls.end()) 2396 PrevDecl = Pos->second; 2397 } 2398 2399 // Merge or overload the declaration with an existing declaration of 2400 // the same name, if appropriate. 2401 if (PrevDecl) { 2402 // Determine whether NewFD is an overload of PrevDecl or 2403 // a declaration that requires merging. If it's an overload, 2404 // there's no more work to do here; we'll just add the new 2405 // function to the scope. 2406 OverloadedFunctionDecl::function_iterator MatchedDecl; 2407 2408 if (!getLangOptions().CPlusPlus && 2409 AllowOverloadingOfFunction(PrevDecl, Context)) { 2410 OverloadableAttrRequired = true; 2411 2412 // Functions marked "overloadable" must have a prototype (that 2413 // we can't get through declaration merging). 2414 if (!NewFD->getType()->getAsFunctionProtoType()) { 2415 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2416 << NewFD; 2417 Redeclaration = true; 2418 2419 // Turn this into a variadic function with no parameters. 2420 QualType R = Context.getFunctionType( 2421 NewFD->getType()->getAsFunctionType()->getResultType(), 2422 0, 0, true, 0); 2423 NewFD->setType(R); 2424 return NewFD->setInvalidDecl(); 2425 } 2426 } 2427 2428 if (PrevDecl && 2429 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2430 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2431 Redeclaration = true; 2432 Decl *OldDecl = PrevDecl; 2433 2434 // If PrevDecl was an overloaded function, extract the 2435 // FunctionDecl that matched. 2436 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2437 OldDecl = *MatchedDecl; 2438 2439 // NewFD and OldDecl represent declarations that need to be 2440 // merged. 2441 if (MergeFunctionDecl(NewFD, OldDecl)) 2442 return NewFD->setInvalidDecl(); 2443 2444 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2445 } 2446 } 2447 2448 // In C++, check default arguments now that we have merged decls. Unless 2449 // the lexical context is the class, because in this case this is done 2450 // during delayed parsing anyway. 2451 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2452 CheckCXXDefaultArguments(NewFD); 2453} 2454 2455bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2456 // FIXME: Need strict checking. In C89, we need to check for 2457 // any assignment, increment, decrement, function-calls, or 2458 // commas outside of a sizeof. In C99, it's the same list, 2459 // except that the aforementioned are allowed in unevaluated 2460 // expressions. Everything else falls under the 2461 // "may accept other forms of constant expressions" exception. 2462 // (We never end up here for C++, so the constant expression 2463 // rules there don't matter.) 2464 if (Init->isConstantInitializer(Context)) 2465 return false; 2466 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2467 << Init->getSourceRange(); 2468 return true; 2469} 2470 2471void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2472 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2473} 2474 2475/// AddInitializerToDecl - Adds the initializer Init to the 2476/// declaration dcl. If DirectInit is true, this is C++ direct 2477/// initialization rather than copy initialization. 2478void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2479 Decl *RealDecl = dcl.getAs<Decl>(); 2480 // If there is no declaration, there was an error parsing it. Just ignore 2481 // the initializer. 2482 if (RealDecl == 0) 2483 return; 2484 2485 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2486 // With declarators parsed the way they are, the parser cannot 2487 // distinguish between a normal initializer and a pure-specifier. 2488 // Thus this grotesque test. 2489 IntegerLiteral *IL; 2490 Expr *Init = static_cast<Expr *>(init.get()); 2491 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2492 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2493 if (Method->isVirtual()) { 2494 Method->setPure(); 2495 2496 // A class is abstract if at least one function is pure virtual. 2497 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2498 } else if (!Method->isInvalidDecl()) { 2499 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2500 << Method->getDeclName() << Init->getSourceRange(); 2501 Method->setInvalidDecl(); 2502 } 2503 } else { 2504 Diag(Method->getLocation(), diag::err_member_function_initialization) 2505 << Method->getDeclName() << Init->getSourceRange(); 2506 Method->setInvalidDecl(); 2507 } 2508 return; 2509 } 2510 2511 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2512 if (!VDecl) { 2513 if (getLangOptions().CPlusPlus && 2514 RealDecl->getLexicalDeclContext()->isRecord() && 2515 isa<NamedDecl>(RealDecl)) 2516 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2517 << cast<NamedDecl>(RealDecl)->getDeclName(); 2518 else 2519 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2520 RealDecl->setInvalidDecl(); 2521 return; 2522 } 2523 2524 if (!VDecl->getType()->isArrayType() && 2525 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2526 diag::err_typecheck_decl_incomplete_type)) { 2527 RealDecl->setInvalidDecl(); 2528 return; 2529 } 2530 2531 const VarDecl *Def = 0; 2532 if (VDecl->getDefinition(Def)) { 2533 Diag(VDecl->getLocation(), diag::err_redefinition) 2534 << VDecl->getDeclName(); 2535 Diag(Def->getLocation(), diag::note_previous_definition); 2536 VDecl->setInvalidDecl(); 2537 return; 2538 } 2539 2540 // Take ownership of the expression, now that we're sure we have somewhere 2541 // to put it. 2542 Expr *Init = init.takeAs<Expr>(); 2543 assert(Init && "missing initializer"); 2544 2545 // Get the decls type and save a reference for later, since 2546 // CheckInitializerTypes may change it. 2547 QualType DclT = VDecl->getType(), SavT = DclT; 2548 if (VDecl->isBlockVarDecl()) { 2549 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2550 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2551 VDecl->setInvalidDecl(); 2552 } else if (!VDecl->isInvalidDecl()) { 2553 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2554 VDecl->getDeclName(), DirectInit)) 2555 VDecl->setInvalidDecl(); 2556 2557 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2558 // Don't check invalid declarations to avoid emitting useless diagnostics. 2559 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2560 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2561 CheckForConstantInitializer(Init, DclT); 2562 } 2563 } 2564 } else if (VDecl->isStaticDataMember() && 2565 VDecl->getLexicalDeclContext()->isRecord()) { 2566 // This is an in-class initialization for a static data member, e.g., 2567 // 2568 // struct S { 2569 // static const int value = 17; 2570 // }; 2571 2572 // Attach the initializer 2573 VDecl->setInit(Init); 2574 2575 // C++ [class.mem]p4: 2576 // A member-declarator can contain a constant-initializer only 2577 // if it declares a static member (9.4) of const integral or 2578 // const enumeration type, see 9.4.2. 2579 QualType T = VDecl->getType(); 2580 if (!T->isDependentType() && 2581 (!Context.getCanonicalType(T).isConstQualified() || 2582 !T->isIntegralType())) { 2583 Diag(VDecl->getLocation(), diag::err_member_initialization) 2584 << VDecl->getDeclName() << Init->getSourceRange(); 2585 VDecl->setInvalidDecl(); 2586 } else { 2587 // C++ [class.static.data]p4: 2588 // If a static data member is of const integral or const 2589 // enumeration type, its declaration in the class definition 2590 // can specify a constant-initializer which shall be an 2591 // integral constant expression (5.19). 2592 if (!Init->isTypeDependent() && 2593 !Init->getType()->isIntegralType()) { 2594 // We have a non-dependent, non-integral or enumeration type. 2595 Diag(Init->getSourceRange().getBegin(), 2596 diag::err_in_class_initializer_non_integral_type) 2597 << Init->getType() << Init->getSourceRange(); 2598 VDecl->setInvalidDecl(); 2599 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2600 // Check whether the expression is a constant expression. 2601 llvm::APSInt Value; 2602 SourceLocation Loc; 2603 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2604 Diag(Loc, diag::err_in_class_initializer_non_constant) 2605 << Init->getSourceRange(); 2606 VDecl->setInvalidDecl(); 2607 } else if (!VDecl->getType()->isDependentType()) 2608 ImpCastExprToType(Init, VDecl->getType()); 2609 } 2610 } 2611 } else if (VDecl->isFileVarDecl()) { 2612 if (VDecl->getStorageClass() == VarDecl::Extern) 2613 Diag(VDecl->getLocation(), diag::warn_extern_init); 2614 if (!VDecl->isInvalidDecl()) 2615 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2616 VDecl->getDeclName(), DirectInit)) 2617 VDecl->setInvalidDecl(); 2618 2619 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2620 // Don't check invalid declarations to avoid emitting useless diagnostics. 2621 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2622 // C99 6.7.8p4. All file scoped initializers need to be constant. 2623 CheckForConstantInitializer(Init, DclT); 2624 } 2625 } 2626 // If the type changed, it means we had an incomplete type that was 2627 // completed by the initializer. For example: 2628 // int ary[] = { 1, 3, 5 }; 2629 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2630 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2631 VDecl->setType(DclT); 2632 Init->setType(DclT); 2633 } 2634 2635 // Attach the initializer to the decl. 2636 VDecl->setInit(Init); 2637 2638 // If the previous declaration of VDecl was a tentative definition, 2639 // remove it from the set of tentative definitions. 2640 if (VDecl->getPreviousDeclaration() && 2641 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2642 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2643 = TentativeDefinitions.find(VDecl->getDeclName()); 2644 assert(Pos != TentativeDefinitions.end() && 2645 "Unrecorded tentative definition?"); 2646 TentativeDefinitions.erase(Pos); 2647 } 2648 2649 return; 2650} 2651 2652void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2653 Decl *RealDecl = dcl.getAs<Decl>(); 2654 2655 // If there is no declaration, there was an error parsing it. Just ignore it. 2656 if (RealDecl == 0) 2657 return; 2658 2659 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2660 QualType Type = Var->getType(); 2661 2662 // Record tentative definitions. 2663 if (Var->isTentativeDefinition(Context)) 2664 TentativeDefinitions[Var->getDeclName()] = Var; 2665 2666 // C++ [dcl.init.ref]p3: 2667 // The initializer can be omitted for a reference only in a 2668 // parameter declaration (8.3.5), in the declaration of a 2669 // function return type, in the declaration of a class member 2670 // within its class declaration (9.2), and where the extern 2671 // specifier is explicitly used. 2672 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2673 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2674 << Var->getDeclName() 2675 << SourceRange(Var->getLocation(), Var->getLocation()); 2676 Var->setInvalidDecl(); 2677 return; 2678 } 2679 2680 // C++ [dcl.init]p9: 2681 // 2682 // If no initializer is specified for an object, and the object 2683 // is of (possibly cv-qualified) non-POD class type (or array 2684 // thereof), the object shall be default-initialized; if the 2685 // object is of const-qualified type, the underlying class type 2686 // shall have a user-declared default constructor. 2687 if (getLangOptions().CPlusPlus) { 2688 QualType InitType = Type; 2689 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2690 InitType = Array->getElementType(); 2691 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2692 CXXRecordDecl *RD = 2693 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2694 CXXConstructorDecl *Constructor = 0; 2695 if (!RequireCompleteType(Var->getLocation(), InitType, 2696 diag::err_invalid_incomplete_type_use)) 2697 Constructor 2698 = PerformInitializationByConstructor(InitType, 0, 0, 2699 Var->getLocation(), 2700 SourceRange(Var->getLocation(), 2701 Var->getLocation()), 2702 Var->getDeclName(), 2703 IK_Default); 2704 if (!Constructor) 2705 Var->setInvalidDecl(); 2706 else if (!RD->hasTrivialConstructor()) 2707 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2708 } 2709 } 2710 2711#if 0 2712 // FIXME: Temporarily disabled because we are not properly parsing 2713 // linkage specifications on declarations, e.g., 2714 // 2715 // extern "C" const CGPoint CGPointerZero; 2716 // 2717 // C++ [dcl.init]p9: 2718 // 2719 // If no initializer is specified for an object, and the 2720 // object is of (possibly cv-qualified) non-POD class type (or 2721 // array thereof), the object shall be default-initialized; if 2722 // the object is of const-qualified type, the underlying class 2723 // type shall have a user-declared default 2724 // constructor. Otherwise, if no initializer is specified for 2725 // an object, the object and its subobjects, if any, have an 2726 // indeterminate initial value; if the object or any of its 2727 // subobjects are of const-qualified type, the program is 2728 // ill-formed. 2729 // 2730 // This isn't technically an error in C, so we don't diagnose it. 2731 // 2732 // FIXME: Actually perform the POD/user-defined default 2733 // constructor check. 2734 if (getLangOptions().CPlusPlus && 2735 Context.getCanonicalType(Type).isConstQualified() && 2736 !Var->hasExternalStorage()) 2737 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2738 << Var->getName() 2739 << SourceRange(Var->getLocation(), Var->getLocation()); 2740#endif 2741 } 2742} 2743 2744Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2745 unsigned NumDecls) { 2746 llvm::SmallVector<Decl*, 8> Decls; 2747 2748 for (unsigned i = 0; i != NumDecls; ++i) 2749 if (Decl *D = Group[i].getAs<Decl>()) 2750 Decls.push_back(D); 2751 2752 // Perform semantic analysis that depends on having fully processed both 2753 // the declarator and initializer. 2754 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2755 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2756 if (!IDecl) 2757 continue; 2758 QualType T = IDecl->getType(); 2759 2760 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2761 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2762 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2763 if (!IDecl->isInvalidDecl() && 2764 RequireCompleteType(IDecl->getLocation(), T, 2765 diag::err_typecheck_decl_incomplete_type)) 2766 IDecl->setInvalidDecl(); 2767 } 2768 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2769 // object that has file scope without an initializer, and without a 2770 // storage-class specifier or with the storage-class specifier "static", 2771 // constitutes a tentative definition. Note: A tentative definition with 2772 // external linkage is valid (C99 6.2.2p5). 2773 if (IDecl->isTentativeDefinition(Context)) { 2774 QualType CheckType = T; 2775 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2776 2777 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2778 if (ArrayT) { 2779 CheckType = ArrayT->getElementType(); 2780 DiagID = diag::err_illegal_decl_array_incomplete_type; 2781 } 2782 2783 if (IDecl->isInvalidDecl()) { 2784 // Do nothing with invalid declarations 2785 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2786 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2787 // C99 6.9.2p3: If the declaration of an identifier for an object is 2788 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2789 // declared type shall not be an incomplete type. 2790 IDecl->setInvalidDecl(); 2791 } 2792 } 2793 } 2794 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2795 &Decls[0], Decls.size())); 2796} 2797 2798 2799/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2800/// to introduce parameters into function prototype scope. 2801Sema::DeclPtrTy 2802Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2803 const DeclSpec &DS = D.getDeclSpec(); 2804 2805 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2806 VarDecl::StorageClass StorageClass = VarDecl::None; 2807 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2808 StorageClass = VarDecl::Register; 2809 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2810 Diag(DS.getStorageClassSpecLoc(), 2811 diag::err_invalid_storage_class_in_func_decl); 2812 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2813 } 2814 2815 if (D.getDeclSpec().isThreadSpecified()) 2816 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2817 2818 DiagnoseFunctionSpecifiers(D); 2819 2820 // Check that there are no default arguments inside the type of this 2821 // parameter (C++ only). 2822 if (getLangOptions().CPlusPlus) 2823 CheckExtraCXXDefaultArguments(D); 2824 2825 QualType parmDeclType = GetTypeForDeclarator(D, S); 2826 2827 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2828 // Can this happen for params? We already checked that they don't conflict 2829 // among each other. Here they can only shadow globals, which is ok. 2830 IdentifierInfo *II = D.getIdentifier(); 2831 if (II) { 2832 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2833 if (PrevDecl->isTemplateParameter()) { 2834 // Maybe we will complain about the shadowed template parameter. 2835 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2836 // Just pretend that we didn't see the previous declaration. 2837 PrevDecl = 0; 2838 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2839 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2840 2841 // Recover by removing the name 2842 II = 0; 2843 D.SetIdentifier(0, D.getIdentifierLoc()); 2844 } 2845 } 2846 } 2847 2848 // Parameters can not be abstract class types. 2849 // For record types, this is done by the AbstractClassUsageDiagnoser once 2850 // the class has been completely parsed. 2851 if (!CurContext->isRecord() && 2852 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2853 diag::err_abstract_type_in_decl, 2854 AbstractParamType)) 2855 D.setInvalidType(true); 2856 2857 QualType T = adjustParameterType(parmDeclType); 2858 2859 ParmVarDecl *New; 2860 if (T == parmDeclType) // parameter type did not need adjustment 2861 New = ParmVarDecl::Create(Context, CurContext, 2862 D.getIdentifierLoc(), II, 2863 parmDeclType, StorageClass, 2864 0); 2865 else // keep track of both the adjusted and unadjusted types 2866 New = OriginalParmVarDecl::Create(Context, CurContext, 2867 D.getIdentifierLoc(), II, T, 2868 parmDeclType, StorageClass, 0); 2869 2870 if (D.isInvalidType()) 2871 New->setInvalidDecl(); 2872 2873 // Parameter declarators cannot be interface types. All ObjC objects are 2874 // passed by reference. 2875 if (T->isObjCInterfaceType()) { 2876 Diag(D.getIdentifierLoc(), 2877 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2878 New->setInvalidDecl(); 2879 } 2880 2881 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2882 if (D.getCXXScopeSpec().isSet()) { 2883 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2884 << D.getCXXScopeSpec().getRange(); 2885 New->setInvalidDecl(); 2886 } 2887 2888 // Add the parameter declaration into this scope. 2889 S->AddDecl(DeclPtrTy::make(New)); 2890 if (II) 2891 IdResolver.AddDecl(New); 2892 2893 ProcessDeclAttributes(New, D); 2894 2895 if (New->hasAttr<BlocksAttr>()) { 2896 Diag(New->getLocation(), diag::err_block_on_nonlocal); 2897 } 2898 return DeclPtrTy::make(New); 2899} 2900 2901void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2902 SourceLocation LocAfterDecls) { 2903 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2904 "Not a function declarator!"); 2905 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2906 2907 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2908 // for a K&R function. 2909 if (!FTI.hasPrototype) { 2910 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2911 --i; 2912 if (FTI.ArgInfo[i].Param == 0) { 2913 std::string Code = " int "; 2914 Code += FTI.ArgInfo[i].Ident->getName(); 2915 Code += ";\n"; 2916 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2917 << FTI.ArgInfo[i].Ident 2918 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2919 2920 // Implicitly declare the argument as type 'int' for lack of a better 2921 // type. 2922 DeclSpec DS; 2923 const char* PrevSpec; // unused 2924 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2925 PrevSpec); 2926 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2927 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2928 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2929 } 2930 } 2931 } 2932} 2933 2934Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2935 Declarator &D) { 2936 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2937 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2938 "Not a function declarator!"); 2939 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2940 2941 if (FTI.hasPrototype) { 2942 // FIXME: Diagnose arguments without names in C. 2943 } 2944 2945 Scope *ParentScope = FnBodyScope->getParent(); 2946 2947 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2948 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2949} 2950 2951Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2952 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2953 2954 CurFunctionNeedsScopeChecking = false; 2955 2956 // See if this is a redefinition. 2957 const FunctionDecl *Definition; 2958 if (FD->getBody(Context, Definition)) { 2959 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2960 Diag(Definition->getLocation(), diag::note_previous_definition); 2961 } 2962 2963 // Builtin functions cannot be defined. 2964 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2965 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2966 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2967 FD->setInvalidDecl(); 2968 } 2969 } 2970 2971 // The return type of a function definition must be complete 2972 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2973 QualType ResultType = FD->getResultType(); 2974 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2975 !FD->isInvalidDecl() && 2976 RequireCompleteType(FD->getLocation(), ResultType, 2977 diag::err_func_def_incomplete_result)) 2978 FD->setInvalidDecl(); 2979 2980 // GNU warning -Wmissing-prototypes: 2981 // Warn if a global function is defined without a previous 2982 // prototype declaration. This warning is issued even if the 2983 // definition itself provides a prototype. The aim is to detect 2984 // global functions that fail to be declared in header files. 2985 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2986 !FD->isMain()) { 2987 bool MissingPrototype = true; 2988 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2989 Prev; Prev = Prev->getPreviousDeclaration()) { 2990 // Ignore any declarations that occur in function or method 2991 // scope, because they aren't visible from the header. 2992 if (Prev->getDeclContext()->isFunctionOrMethod()) 2993 continue; 2994 2995 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2996 break; 2997 } 2998 2999 if (MissingPrototype) 3000 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3001 } 3002 3003 PushDeclContext(FnBodyScope, FD); 3004 3005 // Check the validity of our function parameters 3006 CheckParmsForFunctionDef(FD); 3007 3008 // Introduce our parameters into the function scope 3009 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3010 ParmVarDecl *Param = FD->getParamDecl(p); 3011 Param->setOwningFunction(FD); 3012 3013 // If this has an identifier, add it to the scope stack. 3014 if (Param->getIdentifier()) 3015 PushOnScopeChains(Param, FnBodyScope); 3016 } 3017 3018 // Checking attributes of current function definition 3019 // dllimport attribute. 3020 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 3021 // dllimport attribute cannot be applied to definition. 3022 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3023 Diag(FD->getLocation(), 3024 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3025 << "dllimport"; 3026 FD->setInvalidDecl(); 3027 return DeclPtrTy::make(FD); 3028 } else { 3029 // If a symbol previously declared dllimport is later defined, the 3030 // attribute is ignored in subsequent references, and a warning is 3031 // emitted. 3032 Diag(FD->getLocation(), 3033 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3034 << FD->getNameAsCString() << "dllimport"; 3035 } 3036 } 3037 return DeclPtrTy::make(FD); 3038} 3039 3040 3041Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3042 Decl *dcl = D.getAs<Decl>(); 3043 Stmt *Body = BodyArg.takeAs<Stmt>(); 3044 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3045 FD->setBody(Body); 3046 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3047 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3048 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3049 MD->setBody(Body); 3050 } else { 3051 Body->Destroy(Context); 3052 return DeclPtrTy(); 3053 } 3054 PopDeclContext(); 3055 // Verify and clean out per-function state. 3056 3057 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3058 3059 // Check goto/label use. 3060 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3061 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3062 LabelStmt *L = I->second; 3063 3064 // Verify that we have no forward references left. If so, there was a goto 3065 // or address of a label taken, but no definition of it. Label fwd 3066 // definitions are indicated with a null substmt. 3067 if (L->getSubStmt() != 0) 3068 continue; 3069 3070 // Emit error. 3071 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3072 3073 // At this point, we have gotos that use the bogus label. Stitch it into 3074 // the function body so that they aren't leaked and that the AST is well 3075 // formed. 3076 if (Body == 0) { 3077 // The whole function wasn't parsed correctly, just delete this. 3078 L->Destroy(Context); 3079 continue; 3080 } 3081 3082 // Otherwise, the body is valid: we want to stitch the label decl into the 3083 // function somewhere so that it is properly owned and so that the goto 3084 // has a valid target. Do this by creating a new compound stmt with the 3085 // label in it. 3086 3087 // Give the label a sub-statement. 3088 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3089 3090 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3091 cast<CXXTryStmt>(Body)->getTryBlock() : 3092 cast<CompoundStmt>(Body); 3093 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3094 Elements.push_back(L); 3095 Compound->setStmts(Context, &Elements[0], Elements.size()); 3096 } 3097 FunctionLabelMap.clear(); 3098 3099 if (!Body) return D; 3100 3101 // Verify that that gotos and switch cases don't jump into scopes illegally. 3102 if (CurFunctionNeedsScopeChecking) 3103 DiagnoseInvalidJumps(Body); 3104 3105 // C++ constructors that have function-try-blocks can't have return statements 3106 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3107 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3108 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3109 3110 return D; 3111} 3112 3113/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3114/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3115NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3116 IdentifierInfo &II, Scope *S) { 3117 // Before we produce a declaration for an implicitly defined 3118 // function, see whether there was a locally-scoped declaration of 3119 // this name as a function or variable. If so, use that 3120 // (non-visible) declaration, and complain about it. 3121 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3122 = LocallyScopedExternalDecls.find(&II); 3123 if (Pos != LocallyScopedExternalDecls.end()) { 3124 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3125 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3126 return Pos->second; 3127 } 3128 3129 // Extension in C99. Legal in C90, but warn about it. 3130 if (getLangOptions().C99) 3131 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3132 else 3133 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3134 3135 // FIXME: handle stuff like: 3136 // void foo() { extern float X(); } 3137 // void bar() { X(); } <-- implicit decl for X in another scope. 3138 3139 // Set a Declarator for the implicit definition: int foo(); 3140 const char *Dummy; 3141 DeclSpec DS; 3142 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3143 Error = Error; // Silence warning. 3144 assert(!Error && "Error setting up implicit decl!"); 3145 Declarator D(DS, Declarator::BlockContext); 3146 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3147 0, 0, false, false, 0, 0, Loc, D), 3148 SourceLocation()); 3149 D.SetIdentifier(&II, Loc); 3150 3151 // Insert this function into translation-unit scope. 3152 3153 DeclContext *PrevDC = CurContext; 3154 CurContext = Context.getTranslationUnitDecl(); 3155 3156 FunctionDecl *FD = 3157 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3158 FD->setImplicit(); 3159 3160 CurContext = PrevDC; 3161 3162 AddKnownFunctionAttributes(FD); 3163 3164 return FD; 3165} 3166 3167/// \brief Adds any function attributes that we know a priori based on 3168/// the declaration of this function. 3169/// 3170/// These attributes can apply both to implicitly-declared builtins 3171/// (like __builtin___printf_chk) or to library-declared functions 3172/// like NSLog or printf. 3173void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3174 if (FD->isInvalidDecl()) 3175 return; 3176 3177 // If this is a built-in function, map its builtin attributes to 3178 // actual attributes. 3179 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3180 // Handle printf-formatting attributes. 3181 unsigned FormatIdx; 3182 bool HasVAListArg; 3183 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3184 if (!FD->getAttr<FormatAttr>()) 3185 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3186 FormatIdx + 2)); 3187 } 3188 3189 // Mark const if we don't care about errno and that is the only 3190 // thing preventing the function from being const. This allows 3191 // IRgen to use LLVM intrinsics for such functions. 3192 if (!getLangOptions().MathErrno && 3193 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3194 if (!FD->getAttr<ConstAttr>()) 3195 FD->addAttr(::new (Context) ConstAttr()); 3196 } 3197 } 3198 3199 IdentifierInfo *Name = FD->getIdentifier(); 3200 if (!Name) 3201 return; 3202 if ((!getLangOptions().CPlusPlus && 3203 FD->getDeclContext()->isTranslationUnit()) || 3204 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3205 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3206 LinkageSpecDecl::lang_c)) { 3207 // Okay: this could be a libc/libm/Objective-C function we know 3208 // about. 3209 } else 3210 return; 3211 3212 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3213 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3214 // FIXME: We known better than our headers. 3215 const_cast<FormatAttr *>(Format)->setType("printf"); 3216 } else 3217 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3218 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3219 if (!FD->getAttr<FormatAttr>()) 3220 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3221 } 3222} 3223 3224TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3225 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3226 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3227 3228 // Scope manipulation handled by caller. 3229 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3230 D.getIdentifierLoc(), 3231 D.getIdentifier(), 3232 T); 3233 3234 if (TagType *TT = dyn_cast<TagType>(T)) { 3235 TagDecl *TD = TT->getDecl(); 3236 3237 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3238 // keep track of the TypedefDecl. 3239 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3240 TD->setTypedefForAnonDecl(NewTD); 3241 } 3242 3243 if (D.isInvalidType()) 3244 NewTD->setInvalidDecl(); 3245 return NewTD; 3246} 3247 3248 3249/// \brief Determine whether a tag with a given kind is acceptable 3250/// as a redeclaration of the given tag declaration. 3251/// 3252/// \returns true if the new tag kind is acceptable, false otherwise. 3253bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3254 TagDecl::TagKind NewTag, 3255 SourceLocation NewTagLoc, 3256 const IdentifierInfo &Name) { 3257 // C++ [dcl.type.elab]p3: 3258 // The class-key or enum keyword present in the 3259 // elaborated-type-specifier shall agree in kind with the 3260 // declaration to which the name in theelaborated-type-specifier 3261 // refers. This rule also applies to the form of 3262 // elaborated-type-specifier that declares a class-name or 3263 // friend class since it can be construed as referring to the 3264 // definition of the class. Thus, in any 3265 // elaborated-type-specifier, the enum keyword shall be used to 3266 // refer to an enumeration (7.2), the union class-keyshall be 3267 // used to refer to a union (clause 9), and either the class or 3268 // struct class-key shall be used to refer to a class (clause 9) 3269 // declared using the class or struct class-key. 3270 TagDecl::TagKind OldTag = Previous->getTagKind(); 3271 if (OldTag == NewTag) 3272 return true; 3273 3274 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3275 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3276 // Warn about the struct/class tag mismatch. 3277 bool isTemplate = false; 3278 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3279 isTemplate = Record->getDescribedClassTemplate(); 3280 3281 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3282 << (NewTag == TagDecl::TK_class) 3283 << isTemplate << &Name 3284 << (OldTag == TagDecl::TK_class) 3285 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3286 OldTag == TagDecl::TK_class? "class" : "struct"); 3287 Diag(Previous->getLocation(), diag::note_previous_use); 3288 return true; 3289 } 3290 return false; 3291} 3292 3293/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3294/// former case, Name will be non-null. In the later case, Name will be null. 3295/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3296/// reference/declaration/definition of a tag. 3297Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3298 SourceLocation KWLoc, const CXXScopeSpec &SS, 3299 IdentifierInfo *Name, SourceLocation NameLoc, 3300 AttributeList *Attr, AccessSpecifier AS) { 3301 // If this is not a definition, it must have a name. 3302 assert((Name != 0 || TK == TK_Definition) && 3303 "Nameless record must be a definition!"); 3304 3305 TagDecl::TagKind Kind; 3306 switch (TagSpec) { 3307 default: assert(0 && "Unknown tag type!"); 3308 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3309 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3310 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3311 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3312 } 3313 3314 DeclContext *SearchDC = CurContext; 3315 DeclContext *DC = CurContext; 3316 NamedDecl *PrevDecl = 0; 3317 3318 bool Invalid = false; 3319 3320 if (Name && SS.isNotEmpty()) { 3321 // We have a nested-name tag ('struct foo::bar'). 3322 3323 // Check for invalid 'foo::'. 3324 if (SS.isInvalid()) { 3325 Name = 0; 3326 goto CreateNewDecl; 3327 } 3328 3329 if (RequireCompleteDeclContext(SS)) 3330 return DeclPtrTy::make((Decl *)0); 3331 3332 DC = computeDeclContext(SS); 3333 SearchDC = DC; 3334 // Look-up name inside 'foo::'. 3335 PrevDecl 3336 = dyn_cast_or_null<TagDecl>( 3337 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3338 3339 // A tag 'foo::bar' must already exist. 3340 if (PrevDecl == 0) { 3341 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3342 Name = 0; 3343 goto CreateNewDecl; 3344 } 3345 } else if (Name) { 3346 // If this is a named struct, check to see if there was a previous forward 3347 // declaration or definition. 3348 // FIXME: We're looking into outer scopes here, even when we 3349 // shouldn't be. Doing so can result in ambiguities that we 3350 // shouldn't be diagnosing. 3351 LookupResult R = LookupName(S, Name, LookupTagName, 3352 /*RedeclarationOnly=*/(TK != TK_Reference)); 3353 if (R.isAmbiguous()) { 3354 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3355 // FIXME: This is not best way to recover from case like: 3356 // 3357 // struct S s; 3358 // 3359 // causes needless "incomplete type" error later. 3360 Name = 0; 3361 PrevDecl = 0; 3362 Invalid = true; 3363 } 3364 else 3365 PrevDecl = R; 3366 3367 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3368 // FIXME: This makes sure that we ignore the contexts associated 3369 // with C structs, unions, and enums when looking for a matching 3370 // tag declaration or definition. See the similar lookup tweak 3371 // in Sema::LookupName; is there a better way to deal with this? 3372 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3373 SearchDC = SearchDC->getParent(); 3374 } 3375 } 3376 3377 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3378 // Maybe we will complain about the shadowed template parameter. 3379 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3380 // Just pretend that we didn't see the previous declaration. 3381 PrevDecl = 0; 3382 } 3383 3384 if (PrevDecl) { 3385 // Check whether the previous declaration is usable. 3386 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3387 3388 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3389 // If this is a use of a previous tag, or if the tag is already declared 3390 // in the same scope (so that the definition/declaration completes or 3391 // rementions the tag), reuse the decl. 3392 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3393 // Make sure that this wasn't declared as an enum and now used as a 3394 // struct or something similar. 3395 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3396 bool SafeToContinue 3397 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3398 Kind != TagDecl::TK_enum); 3399 if (SafeToContinue) 3400 Diag(KWLoc, diag::err_use_with_wrong_tag) 3401 << Name 3402 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3403 PrevTagDecl->getKindName()); 3404 else 3405 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3406 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3407 3408 if (SafeToContinue) 3409 Kind = PrevTagDecl->getTagKind(); 3410 else { 3411 // Recover by making this an anonymous redefinition. 3412 Name = 0; 3413 PrevDecl = 0; 3414 Invalid = true; 3415 } 3416 } 3417 3418 if (!Invalid) { 3419 // If this is a use, just return the declaration we found. 3420 3421 // FIXME: In the future, return a variant or some other clue 3422 // for the consumer of this Decl to know it doesn't own it. 3423 // For our current ASTs this shouldn't be a problem, but will 3424 // need to be changed with DeclGroups. 3425 if (TK == TK_Reference) 3426 return DeclPtrTy::make(PrevDecl); 3427 3428 // Diagnose attempts to redefine a tag. 3429 if (TK == TK_Definition) { 3430 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3431 Diag(NameLoc, diag::err_redefinition) << Name; 3432 Diag(Def->getLocation(), diag::note_previous_definition); 3433 // If this is a redefinition, recover by making this 3434 // struct be anonymous, which will make any later 3435 // references get the previous definition. 3436 Name = 0; 3437 PrevDecl = 0; 3438 Invalid = true; 3439 } else { 3440 // If the type is currently being defined, complain 3441 // about a nested redefinition. 3442 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3443 if (Tag->isBeingDefined()) { 3444 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3445 Diag(PrevTagDecl->getLocation(), 3446 diag::note_previous_definition); 3447 Name = 0; 3448 PrevDecl = 0; 3449 Invalid = true; 3450 } 3451 } 3452 3453 // Okay, this is definition of a previously declared or referenced 3454 // tag PrevDecl. We're going to create a new Decl for it. 3455 } 3456 } 3457 // If we get here we have (another) forward declaration or we 3458 // have a definition. Just create a new decl. 3459 } else { 3460 // If we get here, this is a definition of a new tag type in a nested 3461 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3462 // new decl/type. We set PrevDecl to NULL so that the entities 3463 // have distinct types. 3464 PrevDecl = 0; 3465 } 3466 // If we get here, we're going to create a new Decl. If PrevDecl 3467 // is non-NULL, it's a definition of the tag declared by 3468 // PrevDecl. If it's NULL, we have a new definition. 3469 } else { 3470 // PrevDecl is a namespace, template, or anything else 3471 // that lives in the IDNS_Tag identifier namespace. 3472 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3473 // The tag name clashes with a namespace name, issue an error and 3474 // recover by making this tag be anonymous. 3475 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3476 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3477 Name = 0; 3478 PrevDecl = 0; 3479 Invalid = true; 3480 } else { 3481 // The existing declaration isn't relevant to us; we're in a 3482 // new scope, so clear out the previous declaration. 3483 PrevDecl = 0; 3484 } 3485 } 3486 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3487 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3488 // C++ [basic.scope.pdecl]p5: 3489 // -- for an elaborated-type-specifier of the form 3490 // 3491 // class-key identifier 3492 // 3493 // if the elaborated-type-specifier is used in the 3494 // decl-specifier-seq or parameter-declaration-clause of a 3495 // function defined in namespace scope, the identifier is 3496 // declared as a class-name in the namespace that contains 3497 // the declaration; otherwise, except as a friend 3498 // declaration, the identifier is declared in the smallest 3499 // non-class, non-function-prototype scope that contains the 3500 // declaration. 3501 // 3502 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3503 // C structs and unions. 3504 // 3505 // GNU C also supports this behavior as part of its incomplete 3506 // enum types extension, while GNU C++ does not. 3507 // 3508 // Find the context where we'll be declaring the tag. 3509 // FIXME: We would like to maintain the current DeclContext as the 3510 // lexical context, 3511 while (SearchDC->isRecord()) 3512 SearchDC = SearchDC->getParent(); 3513 3514 // Find the scope where we'll be declaring the tag. 3515 while (S->isClassScope() || 3516 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3517 ((S->getFlags() & Scope::DeclScope) == 0) || 3518 (S->getEntity() && 3519 ((DeclContext *)S->getEntity())->isTransparentContext())) 3520 S = S->getParent(); 3521 } 3522 3523CreateNewDecl: 3524 3525 // If there is an identifier, use the location of the identifier as the 3526 // location of the decl, otherwise use the location of the struct/union 3527 // keyword. 3528 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3529 3530 // Otherwise, create a new declaration. If there is a previous 3531 // declaration of the same entity, the two will be linked via 3532 // PrevDecl. 3533 TagDecl *New; 3534 3535 if (Kind == TagDecl::TK_enum) { 3536 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3537 // enum X { A, B, C } D; D should chain to X. 3538 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3539 cast_or_null<EnumDecl>(PrevDecl)); 3540 // If this is an undefined enum, warn. 3541 if (TK != TK_Definition && !Invalid) { 3542 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3543 : diag::ext_forward_ref_enum; 3544 Diag(Loc, DK); 3545 } 3546 } else { 3547 // struct/union/class 3548 3549 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3550 // struct X { int A; } D; D should chain to X. 3551 if (getLangOptions().CPlusPlus) 3552 // FIXME: Look for a way to use RecordDecl for simple structs. 3553 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3554 cast_or_null<CXXRecordDecl>(PrevDecl)); 3555 else 3556 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3557 cast_or_null<RecordDecl>(PrevDecl)); 3558 } 3559 3560 if (Kind != TagDecl::TK_enum) { 3561 // Handle #pragma pack: if the #pragma pack stack has non-default 3562 // alignment, make up a packed attribute for this decl. These 3563 // attributes are checked when the ASTContext lays out the 3564 // structure. 3565 // 3566 // It is important for implementing the correct semantics that this 3567 // happen here (in act on tag decl). The #pragma pack stack is 3568 // maintained as a result of parser callbacks which can occur at 3569 // many points during the parsing of a struct declaration (because 3570 // the #pragma tokens are effectively skipped over during the 3571 // parsing of the struct). 3572 if (unsigned Alignment = getPragmaPackAlignment()) 3573 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3574 } 3575 3576 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3577 // C++ [dcl.typedef]p3: 3578 // [...] Similarly, in a given scope, a class or enumeration 3579 // shall not be declared with the same name as a typedef-name 3580 // that is declared in that scope and refers to a type other 3581 // than the class or enumeration itself. 3582 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3583 TypedefDecl *PrevTypedef = 0; 3584 if (Lookup.getKind() == LookupResult::Found) 3585 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3586 3587 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3588 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3589 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3590 Diag(Loc, diag::err_tag_definition_of_typedef) 3591 << Context.getTypeDeclType(New) 3592 << PrevTypedef->getUnderlyingType(); 3593 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3594 Invalid = true; 3595 } 3596 } 3597 3598 if (Invalid) 3599 New->setInvalidDecl(); 3600 3601 if (Attr) 3602 ProcessDeclAttributeList(New, Attr); 3603 3604 // If we're declaring or defining a tag in function prototype scope 3605 // in C, note that this type can only be used within the function. 3606 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3607 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3608 3609 // Set the lexical context. If the tag has a C++ scope specifier, the 3610 // lexical context will be different from the semantic context. 3611 New->setLexicalDeclContext(CurContext); 3612 3613 // Set the access specifier. 3614 SetMemberAccessSpecifier(New, PrevDecl, AS); 3615 3616 if (TK == TK_Definition) 3617 New->startDefinition(); 3618 3619 // If this has an identifier, add it to the scope stack. 3620 if (Name) { 3621 S = getNonFieldDeclScope(S); 3622 PushOnScopeChains(New, S); 3623 } else { 3624 CurContext->addDecl(Context, New); 3625 } 3626 3627 return DeclPtrTy::make(New); 3628} 3629 3630void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3631 AdjustDeclIfTemplate(TagD); 3632 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3633 3634 // Enter the tag context. 3635 PushDeclContext(S, Tag); 3636 3637 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3638 FieldCollector->StartClass(); 3639 3640 if (Record->getIdentifier()) { 3641 // C++ [class]p2: 3642 // [...] The class-name is also inserted into the scope of the 3643 // class itself; this is known as the injected-class-name. For 3644 // purposes of access checking, the injected-class-name is treated 3645 // as if it were a public member name. 3646 CXXRecordDecl *InjectedClassName 3647 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3648 CurContext, Record->getLocation(), 3649 Record->getIdentifier(), Record); 3650 InjectedClassName->setImplicit(); 3651 InjectedClassName->setAccess(AS_public); 3652 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3653 InjectedClassName->setDescribedClassTemplate(Template); 3654 PushOnScopeChains(InjectedClassName, S); 3655 assert(InjectedClassName->isInjectedClassName() && 3656 "Broken injected-class-name"); 3657 } 3658 } 3659} 3660 3661void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3662 AdjustDeclIfTemplate(TagD); 3663 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3664 3665 if (isa<CXXRecordDecl>(Tag)) 3666 FieldCollector->FinishClass(); 3667 3668 // Exit this scope of this tag's definition. 3669 PopDeclContext(); 3670 3671 // Notify the consumer that we've defined a tag. 3672 Consumer.HandleTagDeclDefinition(Tag); 3673} 3674 3675// Note that FieldName may be null for anonymous bitfields. 3676bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3677 QualType FieldTy, const Expr *BitWidth) { 3678 3679 // C99 6.7.2.1p4 - verify the field type. 3680 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3681 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3682 // Handle incomplete types with specific error. 3683 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3684 return true; 3685 if (FieldName) 3686 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3687 << FieldName << FieldTy << BitWidth->getSourceRange(); 3688 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3689 << FieldTy << BitWidth->getSourceRange(); 3690 } 3691 3692 // If the bit-width is type- or value-dependent, don't try to check 3693 // it now. 3694 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3695 return false; 3696 3697 llvm::APSInt Value; 3698 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3699 return true; 3700 3701 // Zero-width bitfield is ok for anonymous field. 3702 if (Value == 0 && FieldName) 3703 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3704 3705 if (Value.isSigned() && Value.isNegative()) { 3706 if (FieldName) 3707 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3708 << FieldName << Value.toString(10); 3709 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3710 << Value.toString(10); 3711 } 3712 3713 if (!FieldTy->isDependentType()) { 3714 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3715 if (Value.getZExtValue() > TypeSize) { 3716 if (FieldName) 3717 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3718 << FieldName << (unsigned)TypeSize; 3719 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3720 << (unsigned)TypeSize; 3721 } 3722 } 3723 3724 return false; 3725} 3726 3727/// ActOnField - Each field of a struct/union/class is passed into this in order 3728/// to create a FieldDecl object for it. 3729Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3730 SourceLocation DeclStart, 3731 Declarator &D, ExprTy *BitfieldWidth) { 3732 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3733 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3734 AS_public); 3735 return DeclPtrTy::make(Res); 3736} 3737 3738/// HandleField - Analyze a field of a C struct or a C++ data member. 3739/// 3740FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3741 SourceLocation DeclStart, 3742 Declarator &D, Expr *BitWidth, 3743 AccessSpecifier AS) { 3744 IdentifierInfo *II = D.getIdentifier(); 3745 SourceLocation Loc = DeclStart; 3746 if (II) Loc = D.getIdentifierLoc(); 3747 3748 QualType T = GetTypeForDeclarator(D, S); 3749 if (getLangOptions().CPlusPlus) 3750 CheckExtraCXXDefaultArguments(D); 3751 3752 DiagnoseFunctionSpecifiers(D); 3753 3754 if (D.getDeclSpec().isThreadSpecified()) 3755 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3756 3757 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3758 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3759 PrevDecl = 0; 3760 3761 FieldDecl *NewFD 3762 = CheckFieldDecl(II, T, Record, Loc, 3763 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3764 BitWidth, AS, PrevDecl, &D); 3765 if (NewFD->isInvalidDecl() && PrevDecl) { 3766 // Don't introduce NewFD into scope; there's already something 3767 // with the same name in the same scope. 3768 } else if (II) { 3769 PushOnScopeChains(NewFD, S); 3770 } else 3771 Record->addDecl(Context, NewFD); 3772 3773 return NewFD; 3774} 3775 3776/// \brief Build a new FieldDecl and check its well-formedness. 3777/// 3778/// This routine builds a new FieldDecl given the fields name, type, 3779/// record, etc. \p PrevDecl should refer to any previous declaration 3780/// with the same name and in the same scope as the field to be 3781/// created. 3782/// 3783/// \returns a new FieldDecl. 3784/// 3785/// \todo The Declarator argument is a hack. It will be removed once 3786FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3787 RecordDecl *Record, SourceLocation Loc, 3788 bool Mutable, Expr *BitWidth, 3789 AccessSpecifier AS, NamedDecl *PrevDecl, 3790 Declarator *D) { 3791 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3792 bool InvalidDecl = false; 3793 if (D) InvalidDecl = D->isInvalidType(); 3794 3795 // If we receive a broken type, recover by assuming 'int' and 3796 // marking this declaration as invalid. 3797 if (T.isNull()) { 3798 InvalidDecl = true; 3799 T = Context.IntTy; 3800 } 3801 3802 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3803 // than a variably modified type. 3804 if (T->isVariablyModifiedType()) { 3805 bool SizeIsNegative; 3806 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3807 SizeIsNegative); 3808 if (!FixedTy.isNull()) { 3809 Diag(Loc, diag::warn_illegal_constant_array_size); 3810 T = FixedTy; 3811 } else { 3812 if (SizeIsNegative) 3813 Diag(Loc, diag::err_typecheck_negative_array_size); 3814 else 3815 Diag(Loc, diag::err_typecheck_field_variable_size); 3816 T = Context.IntTy; 3817 InvalidDecl = true; 3818 } 3819 } 3820 3821 // Fields can not have abstract class types 3822 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3823 AbstractFieldType)) 3824 InvalidDecl = true; 3825 3826 // If this is declared as a bit-field, check the bit-field. 3827 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3828 InvalidDecl = true; 3829 DeleteExpr(BitWidth); 3830 BitWidth = 0; 3831 } 3832 3833 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3834 Mutable); 3835 if (InvalidDecl) 3836 NewFD->setInvalidDecl(); 3837 3838 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3839 Diag(Loc, diag::err_duplicate_member) << II; 3840 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3841 NewFD->setInvalidDecl(); 3842 } 3843 3844 if (getLangOptions().CPlusPlus && !T->isPODType()) 3845 cast<CXXRecordDecl>(Record)->setPOD(false); 3846 3847 // FIXME: We need to pass in the attributes given an AST 3848 // representation, not a parser representation. 3849 if (D) 3850 ProcessDeclAttributes(NewFD, *D); 3851 3852 if (T.isObjCGCWeak()) 3853 Diag(Loc, diag::warn_attribute_weak_on_field); 3854 3855 NewFD->setAccess(AS); 3856 3857 // C++ [dcl.init.aggr]p1: 3858 // An aggregate is an array or a class (clause 9) with [...] no 3859 // private or protected non-static data members (clause 11). 3860 // A POD must be an aggregate. 3861 if (getLangOptions().CPlusPlus && 3862 (AS == AS_private || AS == AS_protected)) { 3863 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3864 CXXRecord->setAggregate(false); 3865 CXXRecord->setPOD(false); 3866 } 3867 3868 return NewFD; 3869} 3870 3871/// TranslateIvarVisibility - Translate visibility from a token ID to an 3872/// AST enum value. 3873static ObjCIvarDecl::AccessControl 3874TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3875 switch (ivarVisibility) { 3876 default: assert(0 && "Unknown visitibility kind"); 3877 case tok::objc_private: return ObjCIvarDecl::Private; 3878 case tok::objc_public: return ObjCIvarDecl::Public; 3879 case tok::objc_protected: return ObjCIvarDecl::Protected; 3880 case tok::objc_package: return ObjCIvarDecl::Package; 3881 } 3882} 3883 3884/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3885/// in order to create an IvarDecl object for it. 3886Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3887 SourceLocation DeclStart, 3888 Declarator &D, ExprTy *BitfieldWidth, 3889 tok::ObjCKeywordKind Visibility) { 3890 3891 IdentifierInfo *II = D.getIdentifier(); 3892 Expr *BitWidth = (Expr*)BitfieldWidth; 3893 SourceLocation Loc = DeclStart; 3894 if (II) Loc = D.getIdentifierLoc(); 3895 3896 // FIXME: Unnamed fields can be handled in various different ways, for 3897 // example, unnamed unions inject all members into the struct namespace! 3898 3899 QualType T = GetTypeForDeclarator(D, S); 3900 3901 if (BitWidth) { 3902 // 6.7.2.1p3, 6.7.2.1p4 3903 if (VerifyBitField(Loc, II, T, BitWidth)) { 3904 D.setInvalidType(); 3905 DeleteExpr(BitWidth); 3906 BitWidth = 0; 3907 } 3908 } else { 3909 // Not a bitfield. 3910 3911 // validate II. 3912 3913 } 3914 3915 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3916 // than a variably modified type. 3917 if (T->isVariablyModifiedType()) { 3918 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3919 D.setInvalidType(); 3920 } 3921 3922 // Get the visibility (access control) for this ivar. 3923 ObjCIvarDecl::AccessControl ac = 3924 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3925 : ObjCIvarDecl::None; 3926 3927 // Construct the decl. 3928 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3929 (Expr *)BitfieldWidth); 3930 3931 if (II) { 3932 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3933 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3934 && !isa<TagDecl>(PrevDecl)) { 3935 Diag(Loc, diag::err_duplicate_member) << II; 3936 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3937 NewID->setInvalidDecl(); 3938 } 3939 } 3940 3941 // Process attributes attached to the ivar. 3942 ProcessDeclAttributes(NewID, D); 3943 3944 if (D.isInvalidType()) 3945 NewID->setInvalidDecl(); 3946 3947 if (II) { 3948 // FIXME: When interfaces are DeclContexts, we'll need to add 3949 // these to the interface. 3950 S->AddDecl(DeclPtrTy::make(NewID)); 3951 IdResolver.AddDecl(NewID); 3952 } 3953 3954 return DeclPtrTy::make(NewID); 3955} 3956 3957void Sema::ActOnFields(Scope* S, 3958 SourceLocation RecLoc, DeclPtrTy RecDecl, 3959 DeclPtrTy *Fields, unsigned NumFields, 3960 SourceLocation LBrac, SourceLocation RBrac, 3961 AttributeList *Attr) { 3962 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3963 assert(EnclosingDecl && "missing record or interface decl"); 3964 3965 // If the decl this is being inserted into is invalid, then it may be a 3966 // redeclaration or some other bogus case. Don't try to add fields to it. 3967 if (EnclosingDecl->isInvalidDecl()) { 3968 // FIXME: Deallocate fields? 3969 return; 3970 } 3971 3972 3973 // Verify that all the fields are okay. 3974 unsigned NumNamedMembers = 0; 3975 llvm::SmallVector<FieldDecl*, 32> RecFields; 3976 3977 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3978 for (unsigned i = 0; i != NumFields; ++i) { 3979 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3980 3981 // Get the type for the field. 3982 Type *FDTy = FD->getType().getTypePtr(); 3983 3984 if (!FD->isAnonymousStructOrUnion()) { 3985 // Remember all fields written by the user. 3986 RecFields.push_back(FD); 3987 } 3988 3989 // If the field is already invalid for some reason, don't emit more 3990 // diagnostics about it. 3991 if (FD->isInvalidDecl()) 3992 continue; 3993 3994 // C99 6.7.2.1p2: 3995 // A structure or union shall not contain a member with 3996 // incomplete or function type (hence, a structure shall not 3997 // contain an instance of itself, but may contain a pointer to 3998 // an instance of itself), except that the last member of a 3999 // structure with more than one named member may have incomplete 4000 // array type; such a structure (and any union containing, 4001 // possibly recursively, a member that is such a structure) 4002 // shall not be a member of a structure or an element of an 4003 // array. 4004 if (FDTy->isFunctionType()) { 4005 // Field declared as a function. 4006 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4007 << FD->getDeclName(); 4008 FD->setInvalidDecl(); 4009 EnclosingDecl->setInvalidDecl(); 4010 continue; 4011 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4012 Record && Record->isStruct()) { 4013 // Flexible array member. 4014 if (NumNamedMembers < 1) { 4015 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4016 << FD->getDeclName(); 4017 FD->setInvalidDecl(); 4018 EnclosingDecl->setInvalidDecl(); 4019 continue; 4020 } 4021 // Okay, we have a legal flexible array member at the end of the struct. 4022 if (Record) 4023 Record->setHasFlexibleArrayMember(true); 4024 } else if (!FDTy->isDependentType() && 4025 RequireCompleteType(FD->getLocation(), FD->getType(), 4026 diag::err_field_incomplete)) { 4027 // Incomplete type 4028 FD->setInvalidDecl(); 4029 EnclosingDecl->setInvalidDecl(); 4030 continue; 4031 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4032 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4033 // If this is a member of a union, then entire union becomes "flexible". 4034 if (Record && Record->isUnion()) { 4035 Record->setHasFlexibleArrayMember(true); 4036 } else { 4037 // If this is a struct/class and this is not the last element, reject 4038 // it. Note that GCC supports variable sized arrays in the middle of 4039 // structures. 4040 if (i != NumFields-1) 4041 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4042 << FD->getDeclName() << FD->getType(); 4043 else { 4044 // We support flexible arrays at the end of structs in 4045 // other structs as an extension. 4046 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4047 << FD->getDeclName(); 4048 if (Record) 4049 Record->setHasFlexibleArrayMember(true); 4050 } 4051 } 4052 } 4053 } else if (FDTy->isObjCInterfaceType()) { 4054 /// A field cannot be an Objective-c object 4055 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4056 FD->setInvalidDecl(); 4057 EnclosingDecl->setInvalidDecl(); 4058 continue; 4059 } 4060 // Keep track of the number of named members. 4061 if (FD->getIdentifier()) 4062 ++NumNamedMembers; 4063 } 4064 4065 // Okay, we successfully defined 'Record'. 4066 if (Record) { 4067 Record->completeDefinition(Context); 4068 } else { 4069 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 4070 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4071 ID->setIVarList(ClsFields, RecFields.size(), Context); 4072 ID->setLocEnd(RBrac); 4073 4074 // Must enforce the rule that ivars in the base classes may not be 4075 // duplicates. 4076 if (ID->getSuperClass()) { 4077 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4078 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4079 ObjCIvarDecl* Ivar = (*IVI); 4080 4081 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4082 ObjCIvarDecl* prevIvar = 4083 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4084 if (prevIvar) { 4085 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4086 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4087 } 4088 } 4089 } 4090 } 4091 } else if (ObjCImplementationDecl *IMPDecl = 4092 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4093 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4094 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 4095 // FIXME: Set the DeclContext correctly when we build the 4096 // declarations. 4097 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4098 IMPDecl->addDecl(Context, ClsFields[I]); 4099 } 4100 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4101 } 4102 } 4103 4104 if (Attr) 4105 ProcessDeclAttributeList(Record, Attr); 4106} 4107 4108EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4109 EnumConstantDecl *LastEnumConst, 4110 SourceLocation IdLoc, 4111 IdentifierInfo *Id, 4112 ExprArg val) { 4113 Expr *Val = (Expr *)val.get(); 4114 4115 llvm::APSInt EnumVal(32); 4116 QualType EltTy; 4117 if (Val && !Val->isTypeDependent()) { 4118 // Make sure to promote the operand type to int. 4119 UsualUnaryConversions(Val); 4120 if (Val != val.get()) { 4121 val.release(); 4122 val = Val; 4123 } 4124 4125 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4126 SourceLocation ExpLoc; 4127 if (!Val->isValueDependent() && 4128 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4129 Val = 0; 4130 } else { 4131 EltTy = Val->getType(); 4132 } 4133 } 4134 4135 if (!Val) { 4136 if (LastEnumConst) { 4137 // Assign the last value + 1. 4138 EnumVal = LastEnumConst->getInitVal(); 4139 ++EnumVal; 4140 4141 // Check for overflow on increment. 4142 if (EnumVal < LastEnumConst->getInitVal()) 4143 Diag(IdLoc, diag::warn_enum_value_overflow); 4144 4145 EltTy = LastEnumConst->getType(); 4146 } else { 4147 // First value, set to zero. 4148 EltTy = Context.IntTy; 4149 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4150 } 4151 } 4152 4153 val.release(); 4154 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4155 Val, EnumVal); 4156} 4157 4158 4159Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4160 DeclPtrTy lastEnumConst, 4161 SourceLocation IdLoc, 4162 IdentifierInfo *Id, 4163 SourceLocation EqualLoc, ExprTy *val) { 4164 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4165 EnumConstantDecl *LastEnumConst = 4166 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4167 Expr *Val = static_cast<Expr*>(val); 4168 4169 // The scope passed in may not be a decl scope. Zip up the scope tree until 4170 // we find one that is. 4171 S = getNonFieldDeclScope(S); 4172 4173 // Verify that there isn't already something declared with this name in this 4174 // scope. 4175 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4176 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4177 // Maybe we will complain about the shadowed template parameter. 4178 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4179 // Just pretend that we didn't see the previous declaration. 4180 PrevDecl = 0; 4181 } 4182 4183 if (PrevDecl) { 4184 // When in C++, we may get a TagDecl with the same name; in this case the 4185 // enum constant will 'hide' the tag. 4186 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4187 "Received TagDecl when not in C++!"); 4188 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4189 if (isa<EnumConstantDecl>(PrevDecl)) 4190 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4191 else 4192 Diag(IdLoc, diag::err_redefinition) << Id; 4193 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4194 if (Val) Val->Destroy(Context); 4195 return DeclPtrTy(); 4196 } 4197 } 4198 4199 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4200 IdLoc, Id, Owned(Val)); 4201 4202 // Register this decl in the current scope stack. 4203 if (New) 4204 PushOnScopeChains(New, S); 4205 4206 return DeclPtrTy::make(New); 4207} 4208 4209// FIXME: For consistency with ActOnFields(), we should have the parser 4210// pass in the source location for the left/right braces. 4211void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4212 DeclPtrTy *Elements, unsigned NumElements) { 4213 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4214 QualType EnumType = Context.getTypeDeclType(Enum); 4215 4216 // TODO: If the result value doesn't fit in an int, it must be a long or long 4217 // long value. ISO C does not support this, but GCC does as an extension, 4218 // emit a warning. 4219 unsigned IntWidth = Context.Target.getIntWidth(); 4220 4221 // Verify that all the values are okay, compute the size of the values, and 4222 // reverse the list. 4223 unsigned NumNegativeBits = 0; 4224 unsigned NumPositiveBits = 0; 4225 4226 // Keep track of whether all elements have type int. 4227 bool AllElementsInt = true; 4228 4229 for (unsigned i = 0; i != NumElements; ++i) { 4230 EnumConstantDecl *ECD = 4231 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4232 if (!ECD) continue; // Already issued a diagnostic. 4233 4234 // If the enum value doesn't fit in an int, emit an extension warning. 4235 const llvm::APSInt &InitVal = ECD->getInitVal(); 4236 assert(InitVal.getBitWidth() >= IntWidth && 4237 "Should have promoted value to int"); 4238 if (InitVal.getBitWidth() > IntWidth) { 4239 llvm::APSInt V(InitVal); 4240 V.trunc(IntWidth); 4241 V.extend(InitVal.getBitWidth()); 4242 if (V != InitVal) 4243 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4244 << InitVal.toString(10); 4245 } 4246 4247 // Keep track of the size of positive and negative values. 4248 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4249 NumPositiveBits = std::max(NumPositiveBits, 4250 (unsigned)InitVal.getActiveBits()); 4251 else 4252 NumNegativeBits = std::max(NumNegativeBits, 4253 (unsigned)InitVal.getMinSignedBits()); 4254 4255 // Keep track of whether every enum element has type int (very commmon). 4256 if (AllElementsInt) 4257 AllElementsInt = ECD->getType() == Context.IntTy; 4258 } 4259 4260 // Figure out the type that should be used for this enum. 4261 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4262 QualType BestType; 4263 unsigned BestWidth; 4264 4265 if (NumNegativeBits) { 4266 // If there is a negative value, figure out the smallest integer type (of 4267 // int/long/longlong) that fits. 4268 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4269 BestType = Context.IntTy; 4270 BestWidth = IntWidth; 4271 } else { 4272 BestWidth = Context.Target.getLongWidth(); 4273 4274 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4275 BestType = Context.LongTy; 4276 else { 4277 BestWidth = Context.Target.getLongLongWidth(); 4278 4279 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4280 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4281 BestType = Context.LongLongTy; 4282 } 4283 } 4284 } else { 4285 // If there is no negative value, figure out which of uint, ulong, ulonglong 4286 // fits. 4287 if (NumPositiveBits <= IntWidth) { 4288 BestType = Context.UnsignedIntTy; 4289 BestWidth = IntWidth; 4290 } else if (NumPositiveBits <= 4291 (BestWidth = Context.Target.getLongWidth())) { 4292 BestType = Context.UnsignedLongTy; 4293 } else { 4294 BestWidth = Context.Target.getLongLongWidth(); 4295 assert(NumPositiveBits <= BestWidth && 4296 "How could an initializer get larger than ULL?"); 4297 BestType = Context.UnsignedLongLongTy; 4298 } 4299 } 4300 4301 // Loop over all of the enumerator constants, changing their types to match 4302 // the type of the enum if needed. 4303 for (unsigned i = 0; i != NumElements; ++i) { 4304 EnumConstantDecl *ECD = 4305 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4306 if (!ECD) continue; // Already issued a diagnostic. 4307 4308 // Standard C says the enumerators have int type, but we allow, as an 4309 // extension, the enumerators to be larger than int size. If each 4310 // enumerator value fits in an int, type it as an int, otherwise type it the 4311 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4312 // that X has type 'int', not 'unsigned'. 4313 if (ECD->getType() == Context.IntTy) { 4314 // Make sure the init value is signed. 4315 llvm::APSInt IV = ECD->getInitVal(); 4316 IV.setIsSigned(true); 4317 ECD->setInitVal(IV); 4318 4319 if (getLangOptions().CPlusPlus) 4320 // C++ [dcl.enum]p4: Following the closing brace of an 4321 // enum-specifier, each enumerator has the type of its 4322 // enumeration. 4323 ECD->setType(EnumType); 4324 continue; // Already int type. 4325 } 4326 4327 // Determine whether the value fits into an int. 4328 llvm::APSInt InitVal = ECD->getInitVal(); 4329 bool FitsInInt; 4330 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4331 FitsInInt = InitVal.getActiveBits() < IntWidth; 4332 else 4333 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4334 4335 // If it fits into an integer type, force it. Otherwise force it to match 4336 // the enum decl type. 4337 QualType NewTy; 4338 unsigned NewWidth; 4339 bool NewSign; 4340 if (FitsInInt) { 4341 NewTy = Context.IntTy; 4342 NewWidth = IntWidth; 4343 NewSign = true; 4344 } else if (ECD->getType() == BestType) { 4345 // Already the right type! 4346 if (getLangOptions().CPlusPlus) 4347 // C++ [dcl.enum]p4: Following the closing brace of an 4348 // enum-specifier, each enumerator has the type of its 4349 // enumeration. 4350 ECD->setType(EnumType); 4351 continue; 4352 } else { 4353 NewTy = BestType; 4354 NewWidth = BestWidth; 4355 NewSign = BestType->isSignedIntegerType(); 4356 } 4357 4358 // Adjust the APSInt value. 4359 InitVal.extOrTrunc(NewWidth); 4360 InitVal.setIsSigned(NewSign); 4361 ECD->setInitVal(InitVal); 4362 4363 // Adjust the Expr initializer and type. 4364 if (ECD->getInitExpr()) 4365 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4366 /*isLvalue=*/false)); 4367 if (getLangOptions().CPlusPlus) 4368 // C++ [dcl.enum]p4: Following the closing brace of an 4369 // enum-specifier, each enumerator has the type of its 4370 // enumeration. 4371 ECD->setType(EnumType); 4372 else 4373 ECD->setType(NewTy); 4374 } 4375 4376 Enum->completeDefinition(Context, BestType); 4377} 4378 4379Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4380 ExprArg expr) { 4381 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4382 4383 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4384 Loc, AsmString)); 4385} 4386