SemaDecl.cpp revision d7eff68dbbbc6b3f8dfd44f6a833c2b320a96e9a
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/Analysis/CFG.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Basic/PartialDiagnostic.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/Basic/TargetInfo.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/BitVector.h" 33#include "llvm/ADT/STLExtras.h" 34#include <algorithm> 35#include <functional> 36#include <queue> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, const CXXScopeSpec *SS, 65 bool isClassName) { 66 // C++ [temp.res]p3: 67 // A qualified-id that refers to a type and in which the 68 // nested-name-specifier depends on a template-parameter (14.6.2) 69 // shall be prefixed by the keyword typename to indicate that the 70 // qualified-id denotes a type, forming an 71 // elaborated-type-specifier (7.1.5.3). 72 // 73 // We therefore do not perform any name lookup if the result would 74 // refer to a member of an unknown specialization. 75 if (SS && isUnknownSpecialization(*SS)) { 76 if (!isClassName) 77 return 0; 78 79 // We know from the grammar that this name refers to a type, so build a 80 // TypenameType node to describe the type. 81 // FIXME: Record somewhere that this TypenameType node has no "typename" 82 // keyword associated with it. 83 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 84 II, SS->getRange()).getAsOpaquePtr(); 85 } 86 87 LookupResult Result 88 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 89 90 NamedDecl *IIDecl = 0; 91 switch (Result.getKind()) { 92 case LookupResult::NotFound: 93 case LookupResult::FoundOverloaded: 94 return 0; 95 96 case LookupResult::AmbiguousBaseSubobjectTypes: 97 case LookupResult::AmbiguousBaseSubobjects: 98 case LookupResult::AmbiguousReference: { 99 // Look to see if we have a type anywhere in the list of results. 100 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 101 Res != ResEnd; ++Res) { 102 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 103 if (!IIDecl || 104 (*Res)->getLocation().getRawEncoding() < 105 IIDecl->getLocation().getRawEncoding()) 106 IIDecl = *Res; 107 } 108 } 109 110 if (!IIDecl) { 111 // None of the entities we found is a type, so there is no way 112 // to even assume that the result is a type. In this case, don't 113 // complain about the ambiguity. The parser will either try to 114 // perform this lookup again (e.g., as an object name), which 115 // will produce the ambiguity, or will complain that it expected 116 // a type name. 117 Result.Destroy(); 118 return 0; 119 } 120 121 // We found a type within the ambiguous lookup; diagnose the 122 // ambiguity and then return that type. This might be the right 123 // answer, or it might not be, but it suppresses any attempt to 124 // perform the name lookup again. 125 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 126 break; 127 } 128 129 case LookupResult::Found: 130 IIDecl = Result.getAsDecl(); 131 break; 132 } 133 134 if (IIDecl) { 135 QualType T; 136 137 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 138 // Check whether we can use this type 139 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 140 141 if (getLangOptions().CPlusPlus) { 142 // C++ [temp.local]p2: 143 // Within the scope of a class template specialization or 144 // partial specialization, when the injected-class-name is 145 // not followed by a <, it is equivalent to the 146 // injected-class-name followed by the template-argument s 147 // of the class template specialization or partial 148 // specialization enclosed in <>. 149 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 150 if (RD->isInjectedClassName()) 151 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 152 T = Template->getInjectedClassNameType(Context); 153 } 154 155 if (T.isNull()) 156 T = Context.getTypeDeclType(TD); 157 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 158 // Check whether we can use this interface. 159 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 160 161 T = Context.getObjCInterfaceType(IDecl); 162 } else 163 return 0; 164 165 if (SS) 166 T = getQualifiedNameType(*SS, T); 167 168 return T.getAsOpaquePtr(); 169 } 170 171 return 0; 172} 173 174/// isTagName() - This method is called *for error recovery purposes only* 175/// to determine if the specified name is a valid tag name ("struct foo"). If 176/// so, this returns the TST for the tag corresponding to it (TST_enum, 177/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 178/// where the user forgot to specify the tag. 179DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 180 // Do a tag name lookup in this scope. 181 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 182 if (R.getKind() == LookupResult::Found) 183 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 184 switch (TD->getTagKind()) { 185 case TagDecl::TK_struct: return DeclSpec::TST_struct; 186 case TagDecl::TK_union: return DeclSpec::TST_union; 187 case TagDecl::TK_class: return DeclSpec::TST_class; 188 case TagDecl::TK_enum: return DeclSpec::TST_enum; 189 } 190 } 191 192 return DeclSpec::TST_unspecified; 193} 194 195 196// Determines the context to return to after temporarily entering a 197// context. This depends in an unnecessarily complicated way on the 198// exact ordering of callbacks from the parser. 199DeclContext *Sema::getContainingDC(DeclContext *DC) { 200 201 // Functions defined inline within classes aren't parsed until we've 202 // finished parsing the top-level class, so the top-level class is 203 // the context we'll need to return to. 204 if (isa<FunctionDecl>(DC)) { 205 DC = DC->getLexicalParent(); 206 207 // A function not defined within a class will always return to its 208 // lexical context. 209 if (!isa<CXXRecordDecl>(DC)) 210 return DC; 211 212 // A C++ inline method/friend is parsed *after* the topmost class 213 // it was declared in is fully parsed ("complete"); the topmost 214 // class is the context we need to return to. 215 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 216 DC = RD; 217 218 // Return the declaration context of the topmost class the inline method is 219 // declared in. 220 return DC; 221 } 222 223 if (isa<ObjCMethodDecl>(DC)) 224 return Context.getTranslationUnitDecl(); 225 226 return DC->getLexicalParent(); 227} 228 229void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 230 assert(getContainingDC(DC) == CurContext && 231 "The next DeclContext should be lexically contained in the current one."); 232 CurContext = DC; 233 S->setEntity(DC); 234} 235 236void Sema::PopDeclContext() { 237 assert(CurContext && "DeclContext imbalance!"); 238 239 CurContext = getContainingDC(CurContext); 240} 241 242/// EnterDeclaratorContext - Used when we must lookup names in the context 243/// of a declarator's nested name specifier. 244void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 245 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 246 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 247 CurContext = DC; 248 assert(CurContext && "No context?"); 249 S->setEntity(CurContext); 250} 251 252void Sema::ExitDeclaratorContext(Scope *S) { 253 S->setEntity(PreDeclaratorDC); 254 PreDeclaratorDC = 0; 255 256 // Reset CurContext to the nearest enclosing context. 257 while (!S->getEntity() && S->getParent()) 258 S = S->getParent(); 259 CurContext = static_cast<DeclContext*>(S->getEntity()); 260 assert(CurContext && "No context?"); 261} 262 263/// \brief Determine whether we allow overloading of the function 264/// PrevDecl with another declaration. 265/// 266/// This routine determines whether overloading is possible, not 267/// whether some new function is actually an overload. It will return 268/// true in C++ (where we can always provide overloads) or, as an 269/// extension, in C when the previous function is already an 270/// overloaded function declaration or has the "overloadable" 271/// attribute. 272static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 273 if (Context.getLangOptions().CPlusPlus) 274 return true; 275 276 if (isa<OverloadedFunctionDecl>(PrevDecl)) 277 return true; 278 279 return PrevDecl->getAttr<OverloadableAttr>() != 0; 280} 281 282/// Add this decl to the scope shadowed decl chains. 283void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 284 // Move up the scope chain until we find the nearest enclosing 285 // non-transparent context. The declaration will be introduced into this 286 // scope. 287 while (S->getEntity() && 288 ((DeclContext *)S->getEntity())->isTransparentContext()) 289 S = S->getParent(); 290 291 S->AddDecl(DeclPtrTy::make(D)); 292 293 // Add scoped declarations into their context, so that they can be 294 // found later. Declarations without a context won't be inserted 295 // into any context. 296 if (AddToContext) 297 CurContext->addDecl(D); 298 299 // C++ [basic.scope]p4: 300 // -- exactly one declaration shall declare a class name or 301 // enumeration name that is not a typedef name and the other 302 // declarations shall all refer to the same object or 303 // enumerator, or all refer to functions and function templates; 304 // in this case the class name or enumeration name is hidden. 305 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 306 // We are pushing the name of a tag (enum or class). 307 if (CurContext->getLookupContext() 308 == TD->getDeclContext()->getLookupContext()) { 309 // We're pushing the tag into the current context, which might 310 // require some reshuffling in the identifier resolver. 311 IdentifierResolver::iterator 312 I = IdResolver.begin(TD->getDeclName()), 313 IEnd = IdResolver.end(); 314 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 315 NamedDecl *PrevDecl = *I; 316 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 317 PrevDecl = *I, ++I) { 318 if (TD->declarationReplaces(*I)) { 319 // This is a redeclaration. Remove it from the chain and 320 // break out, so that we'll add in the shadowed 321 // declaration. 322 S->RemoveDecl(DeclPtrTy::make(*I)); 323 if (PrevDecl == *I) { 324 IdResolver.RemoveDecl(*I); 325 IdResolver.AddDecl(TD); 326 return; 327 } else { 328 IdResolver.RemoveDecl(*I); 329 break; 330 } 331 } 332 } 333 334 // There is already a declaration with the same name in the same 335 // scope, which is not a tag declaration. It must be found 336 // before we find the new declaration, so insert the new 337 // declaration at the end of the chain. 338 IdResolver.AddShadowedDecl(TD, PrevDecl); 339 340 return; 341 } 342 } 343 } else if ((isa<FunctionDecl>(D) && 344 AllowOverloadingOfFunction(D, Context)) || 345 isa<FunctionTemplateDecl>(D)) { 346 // We are pushing the name of a function or function template, 347 // which might be an overloaded name. 348 IdentifierResolver::iterator Redecl 349 = std::find_if(IdResolver.begin(D->getDeclName()), 350 IdResolver.end(), 351 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 352 D)); 353 if (Redecl != IdResolver.end() && 354 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 355 // There is already a declaration of a function on our 356 // IdResolver chain. Replace it with this declaration. 357 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 358 IdResolver.RemoveDecl(*Redecl); 359 } 360 } else if (isa<ObjCInterfaceDecl>(D)) { 361 // We're pushing an Objective-C interface into the current 362 // context. If there is already an alias declaration, remove it first. 363 for (IdentifierResolver::iterator 364 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 365 I != IEnd; ++I) { 366 if (isa<ObjCCompatibleAliasDecl>(*I)) { 367 S->RemoveDecl(DeclPtrTy::make(*I)); 368 IdResolver.RemoveDecl(*I); 369 break; 370 } 371 } 372 } 373 374 IdResolver.AddDecl(D); 375} 376 377void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 378 if (S->decl_empty()) return; 379 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 380 "Scope shouldn't contain decls!"); 381 382 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 383 I != E; ++I) { 384 Decl *TmpD = (*I).getAs<Decl>(); 385 assert(TmpD && "This decl didn't get pushed??"); 386 387 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 388 NamedDecl *D = cast<NamedDecl>(TmpD); 389 390 if (!D->getDeclName()) continue; 391 392 // Remove this name from our lexical scope. 393 IdResolver.RemoveDecl(D); 394 } 395} 396 397/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 398/// return 0 if one not found. 399ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 400 // The third "scope" argument is 0 since we aren't enabling lazy built-in 401 // creation from this context. 402 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 403 404 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 405} 406 407/// getNonFieldDeclScope - Retrieves the innermost scope, starting 408/// from S, where a non-field would be declared. This routine copes 409/// with the difference between C and C++ scoping rules in structs and 410/// unions. For example, the following code is well-formed in C but 411/// ill-formed in C++: 412/// @code 413/// struct S6 { 414/// enum { BAR } e; 415/// }; 416/// 417/// void test_S6() { 418/// struct S6 a; 419/// a.e = BAR; 420/// } 421/// @endcode 422/// For the declaration of BAR, this routine will return a different 423/// scope. The scope S will be the scope of the unnamed enumeration 424/// within S6. In C++, this routine will return the scope associated 425/// with S6, because the enumeration's scope is a transparent 426/// context but structures can contain non-field names. In C, this 427/// routine will return the translation unit scope, since the 428/// enumeration's scope is a transparent context and structures cannot 429/// contain non-field names. 430Scope *Sema::getNonFieldDeclScope(Scope *S) { 431 while (((S->getFlags() & Scope::DeclScope) == 0) || 432 (S->getEntity() && 433 ((DeclContext *)S->getEntity())->isTransparentContext()) || 434 (S->isClassScope() && !getLangOptions().CPlusPlus)) 435 S = S->getParent(); 436 return S; 437} 438 439void Sema::InitBuiltinVaListType() { 440 if (!Context.getBuiltinVaListType().isNull()) 441 return; 442 443 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 444 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 445 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 446 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 447} 448 449/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 450/// file scope. lazily create a decl for it. ForRedeclaration is true 451/// if we're creating this built-in in anticipation of redeclaring the 452/// built-in. 453NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 454 Scope *S, bool ForRedeclaration, 455 SourceLocation Loc) { 456 Builtin::ID BID = (Builtin::ID)bid; 457 458 if (Context.BuiltinInfo.hasVAListUse(BID)) 459 InitBuiltinVaListType(); 460 461 ASTContext::GetBuiltinTypeError Error; 462 QualType R = Context.GetBuiltinType(BID, Error); 463 switch (Error) { 464 case ASTContext::GE_None: 465 // Okay 466 break; 467 468 case ASTContext::GE_Missing_stdio: 469 if (ForRedeclaration) 470 Diag(Loc, diag::err_implicit_decl_requires_stdio) 471 << Context.BuiltinInfo.GetName(BID); 472 return 0; 473 474 case ASTContext::GE_Missing_setjmp: 475 if (ForRedeclaration) 476 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 477 << Context.BuiltinInfo.GetName(BID); 478 return 0; 479 } 480 481 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 482 Diag(Loc, diag::ext_implicit_lib_function_decl) 483 << Context.BuiltinInfo.GetName(BID) 484 << R; 485 if (Context.BuiltinInfo.getHeaderName(BID) && 486 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 487 != Diagnostic::Ignored) 488 Diag(Loc, diag::note_please_include_header) 489 << Context.BuiltinInfo.getHeaderName(BID) 490 << Context.BuiltinInfo.GetName(BID); 491 } 492 493 FunctionDecl *New = FunctionDecl::Create(Context, 494 Context.getTranslationUnitDecl(), 495 Loc, II, R, /*DInfo=*/0, 496 FunctionDecl::Extern, false, 497 /*hasPrototype=*/true); 498 New->setImplicit(); 499 500 // Create Decl objects for each parameter, adding them to the 501 // FunctionDecl. 502 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 503 llvm::SmallVector<ParmVarDecl*, 16> Params; 504 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 505 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 506 FT->getArgType(i), /*DInfo=*/0, 507 VarDecl::None, 0)); 508 New->setParams(Context, Params.data(), Params.size()); 509 } 510 511 AddKnownFunctionAttributes(New); 512 513 // TUScope is the translation-unit scope to insert this function into. 514 // FIXME: This is hideous. We need to teach PushOnScopeChains to 515 // relate Scopes to DeclContexts, and probably eliminate CurContext 516 // entirely, but we're not there yet. 517 DeclContext *SavedContext = CurContext; 518 CurContext = Context.getTranslationUnitDecl(); 519 PushOnScopeChains(New, TUScope); 520 CurContext = SavedContext; 521 return New; 522} 523 524/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 525/// everything from the standard library is defined. 526NamespaceDecl *Sema::GetStdNamespace() { 527 if (!StdNamespace) { 528 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 529 DeclContext *Global = Context.getTranslationUnitDecl(); 530 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 531 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 532 } 533 return StdNamespace; 534} 535 536/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 537/// same name and scope as a previous declaration 'Old'. Figure out 538/// how to resolve this situation, merging decls or emitting 539/// diagnostics as appropriate. If there was an error, set New to be invalid. 540/// 541void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 542 // If either decl is known invalid already, set the new one to be invalid and 543 // don't bother doing any merging checks. 544 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 545 return New->setInvalidDecl(); 546 547 // Allow multiple definitions for ObjC built-in typedefs. 548 // FIXME: Verify the underlying types are equivalent! 549 if (getLangOptions().ObjC1) { 550 const IdentifierInfo *TypeID = New->getIdentifier(); 551 switch (TypeID->getLength()) { 552 default: break; 553 case 2: 554 if (!TypeID->isStr("id")) 555 break; 556 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 557 // Install the built-in type for 'id', ignoring the current definition. 558 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 559 return; 560 case 5: 561 if (!TypeID->isStr("Class")) 562 break; 563 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 564 // Install the built-in type for 'Class', ignoring the current definition. 565 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 566 return; 567 case 3: 568 if (!TypeID->isStr("SEL")) 569 break; 570 Context.setObjCSelType(Context.getTypeDeclType(New)); 571 return; 572 case 8: 573 if (!TypeID->isStr("Protocol")) 574 break; 575 Context.setObjCProtoType(New->getUnderlyingType()); 576 return; 577 } 578 // Fall through - the typedef name was not a builtin type. 579 } 580 // Verify the old decl was also a type. 581 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 582 if (!Old) { 583 Diag(New->getLocation(), diag::err_redefinition_different_kind) 584 << New->getDeclName(); 585 if (OldD->getLocation().isValid()) 586 Diag(OldD->getLocation(), diag::note_previous_definition); 587 return New->setInvalidDecl(); 588 } 589 590 // Determine the "old" type we'll use for checking and diagnostics. 591 QualType OldType; 592 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 593 OldType = OldTypedef->getUnderlyingType(); 594 else 595 OldType = Context.getTypeDeclType(Old); 596 597 // If the typedef types are not identical, reject them in all languages and 598 // with any extensions enabled. 599 600 if (OldType != New->getUnderlyingType() && 601 Context.getCanonicalType(OldType) != 602 Context.getCanonicalType(New->getUnderlyingType())) { 603 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 604 << New->getUnderlyingType() << OldType; 605 if (Old->getLocation().isValid()) 606 Diag(Old->getLocation(), diag::note_previous_definition); 607 return New->setInvalidDecl(); 608 } 609 610 if (getLangOptions().Microsoft) 611 return; 612 613 // C++ [dcl.typedef]p2: 614 // In a given non-class scope, a typedef specifier can be used to 615 // redefine the name of any type declared in that scope to refer 616 // to the type to which it already refers. 617 if (getLangOptions().CPlusPlus) { 618 if (!isa<CXXRecordDecl>(CurContext)) 619 return; 620 Diag(New->getLocation(), diag::err_redefinition) 621 << New->getDeclName(); 622 Diag(Old->getLocation(), diag::note_previous_definition); 623 return New->setInvalidDecl(); 624 } 625 626 // If we have a redefinition of a typedef in C, emit a warning. This warning 627 // is normally mapped to an error, but can be controlled with 628 // -Wtypedef-redefinition. If either the original or the redefinition is 629 // in a system header, don't emit this for compatibility with GCC. 630 if (PP.getDiagnostics().getSuppressSystemWarnings() && 631 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 632 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 633 return; 634 635 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 636 << New->getDeclName(); 637 Diag(Old->getLocation(), diag::note_previous_definition); 638 return; 639} 640 641/// DeclhasAttr - returns true if decl Declaration already has the target 642/// attribute. 643static bool 644DeclHasAttr(const Decl *decl, const Attr *target) { 645 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 646 if (attr->getKind() == target->getKind()) 647 return true; 648 649 return false; 650} 651 652/// MergeAttributes - append attributes from the Old decl to the New one. 653static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 654 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 655 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 656 Attr *NewAttr = attr->clone(C); 657 NewAttr->setInherited(true); 658 New->addAttr(NewAttr); 659 } 660 } 661} 662 663/// Used in MergeFunctionDecl to keep track of function parameters in 664/// C. 665struct GNUCompatibleParamWarning { 666 ParmVarDecl *OldParm; 667 ParmVarDecl *NewParm; 668 QualType PromotedType; 669}; 670 671/// MergeFunctionDecl - We just parsed a function 'New' from 672/// declarator D which has the same name and scope as a previous 673/// declaration 'Old'. Figure out how to resolve this situation, 674/// merging decls or emitting diagnostics as appropriate. 675/// 676/// In C++, New and Old must be declarations that are not 677/// overloaded. Use IsOverload to determine whether New and Old are 678/// overloaded, and to select the Old declaration that New should be 679/// merged with. 680/// 681/// Returns true if there was an error, false otherwise. 682bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 683 assert(!isa<OverloadedFunctionDecl>(OldD) && 684 "Cannot merge with an overloaded function declaration"); 685 686 // Verify the old decl was also a function. 687 FunctionDecl *Old = 0; 688 if (FunctionTemplateDecl *OldFunctionTemplate 689 = dyn_cast<FunctionTemplateDecl>(OldD)) 690 Old = OldFunctionTemplate->getTemplatedDecl(); 691 else 692 Old = dyn_cast<FunctionDecl>(OldD); 693 if (!Old) { 694 Diag(New->getLocation(), diag::err_redefinition_different_kind) 695 << New->getDeclName(); 696 Diag(OldD->getLocation(), diag::note_previous_definition); 697 return true; 698 } 699 700 // Determine whether the previous declaration was a definition, 701 // implicit declaration, or a declaration. 702 diag::kind PrevDiag; 703 if (Old->isThisDeclarationADefinition()) 704 PrevDiag = diag::note_previous_definition; 705 else if (Old->isImplicit()) 706 PrevDiag = diag::note_previous_implicit_declaration; 707 else 708 PrevDiag = diag::note_previous_declaration; 709 710 QualType OldQType = Context.getCanonicalType(Old->getType()); 711 QualType NewQType = Context.getCanonicalType(New->getType()); 712 713 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 714 New->getStorageClass() == FunctionDecl::Static && 715 Old->getStorageClass() != FunctionDecl::Static) { 716 Diag(New->getLocation(), diag::err_static_non_static) 717 << New; 718 Diag(Old->getLocation(), PrevDiag); 719 return true; 720 } 721 722 if (getLangOptions().CPlusPlus) { 723 // (C++98 13.1p2): 724 // Certain function declarations cannot be overloaded: 725 // -- Function declarations that differ only in the return type 726 // cannot be overloaded. 727 QualType OldReturnType 728 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 729 QualType NewReturnType 730 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 731 if (OldReturnType != NewReturnType) { 732 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 733 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 734 return true; 735 } 736 737 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 738 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 739 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 740 NewMethod->getLexicalDeclContext()->isRecord()) { 741 // -- Member function declarations with the same name and the 742 // same parameter types cannot be overloaded if any of them 743 // is a static member function declaration. 744 if (OldMethod->isStatic() || NewMethod->isStatic()) { 745 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 746 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 747 return true; 748 } 749 750 // C++ [class.mem]p1: 751 // [...] A member shall not be declared twice in the 752 // member-specification, except that a nested class or member 753 // class template can be declared and then later defined. 754 unsigned NewDiag; 755 if (isa<CXXConstructorDecl>(OldMethod)) 756 NewDiag = diag::err_constructor_redeclared; 757 else if (isa<CXXDestructorDecl>(NewMethod)) 758 NewDiag = diag::err_destructor_redeclared; 759 else if (isa<CXXConversionDecl>(NewMethod)) 760 NewDiag = diag::err_conv_function_redeclared; 761 else 762 NewDiag = diag::err_member_redeclared; 763 764 Diag(New->getLocation(), NewDiag); 765 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 766 } 767 768 // (C++98 8.3.5p3): 769 // All declarations for a function shall agree exactly in both the 770 // return type and the parameter-type-list. 771 if (OldQType == NewQType) 772 return MergeCompatibleFunctionDecls(New, Old); 773 774 // Fall through for conflicting redeclarations and redefinitions. 775 } 776 777 // C: Function types need to be compatible, not identical. This handles 778 // duplicate function decls like "void f(int); void f(enum X);" properly. 779 if (!getLangOptions().CPlusPlus && 780 Context.typesAreCompatible(OldQType, NewQType)) { 781 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 782 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 783 const FunctionProtoType *OldProto = 0; 784 if (isa<FunctionNoProtoType>(NewFuncType) && 785 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 786 // The old declaration provided a function prototype, but the 787 // new declaration does not. Merge in the prototype. 788 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 789 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 790 OldProto->arg_type_end()); 791 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 792 ParamTypes.data(), ParamTypes.size(), 793 OldProto->isVariadic(), 794 OldProto->getTypeQuals()); 795 New->setType(NewQType); 796 New->setHasInheritedPrototype(); 797 798 // Synthesize a parameter for each argument type. 799 llvm::SmallVector<ParmVarDecl*, 16> Params; 800 for (FunctionProtoType::arg_type_iterator 801 ParamType = OldProto->arg_type_begin(), 802 ParamEnd = OldProto->arg_type_end(); 803 ParamType != ParamEnd; ++ParamType) { 804 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 805 SourceLocation(), 0, 806 *ParamType, /*DInfo=*/0, 807 VarDecl::None, 0); 808 Param->setImplicit(); 809 Params.push_back(Param); 810 } 811 812 New->setParams(Context, Params.data(), Params.size()); 813 } 814 815 return MergeCompatibleFunctionDecls(New, Old); 816 } 817 818 // GNU C permits a K&R definition to follow a prototype declaration 819 // if the declared types of the parameters in the K&R definition 820 // match the types in the prototype declaration, even when the 821 // promoted types of the parameters from the K&R definition differ 822 // from the types in the prototype. GCC then keeps the types from 823 // the prototype. 824 // 825 // If a variadic prototype is followed by a non-variadic K&R definition, 826 // the K&R definition becomes variadic. This is sort of an edge case, but 827 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 828 // C99 6.9.1p8. 829 if (!getLangOptions().CPlusPlus && 830 Old->hasPrototype() && !New->hasPrototype() && 831 New->getType()->getAsFunctionProtoType() && 832 Old->getNumParams() == New->getNumParams()) { 833 llvm::SmallVector<QualType, 16> ArgTypes; 834 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 835 const FunctionProtoType *OldProto 836 = Old->getType()->getAsFunctionProtoType(); 837 const FunctionProtoType *NewProto 838 = New->getType()->getAsFunctionProtoType(); 839 840 // Determine whether this is the GNU C extension. 841 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 842 NewProto->getResultType()); 843 bool LooseCompatible = !MergedReturn.isNull(); 844 for (unsigned Idx = 0, End = Old->getNumParams(); 845 LooseCompatible && Idx != End; ++Idx) { 846 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 847 ParmVarDecl *NewParm = New->getParamDecl(Idx); 848 if (Context.typesAreCompatible(OldParm->getType(), 849 NewProto->getArgType(Idx))) { 850 ArgTypes.push_back(NewParm->getType()); 851 } else if (Context.typesAreCompatible(OldParm->getType(), 852 NewParm->getType())) { 853 GNUCompatibleParamWarning Warn 854 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 855 Warnings.push_back(Warn); 856 ArgTypes.push_back(NewParm->getType()); 857 } else 858 LooseCompatible = false; 859 } 860 861 if (LooseCompatible) { 862 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 863 Diag(Warnings[Warn].NewParm->getLocation(), 864 diag::ext_param_promoted_not_compatible_with_prototype) 865 << Warnings[Warn].PromotedType 866 << Warnings[Warn].OldParm->getType(); 867 Diag(Warnings[Warn].OldParm->getLocation(), 868 diag::note_previous_declaration); 869 } 870 871 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 872 ArgTypes.size(), 873 OldProto->isVariadic(), 0)); 874 return MergeCompatibleFunctionDecls(New, Old); 875 } 876 877 // Fall through to diagnose conflicting types. 878 } 879 880 // A function that has already been declared has been redeclared or defined 881 // with a different type- show appropriate diagnostic 882 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 883 // The user has declared a builtin function with an incompatible 884 // signature. 885 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 886 // The function the user is redeclaring is a library-defined 887 // function like 'malloc' or 'printf'. Warn about the 888 // redeclaration, then pretend that we don't know about this 889 // library built-in. 890 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 891 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 892 << Old << Old->getType(); 893 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 894 Old->setInvalidDecl(); 895 return false; 896 } 897 898 PrevDiag = diag::note_previous_builtin_declaration; 899 } 900 901 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 902 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 903 return true; 904} 905 906/// \brief Completes the merge of two function declarations that are 907/// known to be compatible. 908/// 909/// This routine handles the merging of attributes and other 910/// properties of function declarations form the old declaration to 911/// the new declaration, once we know that New is in fact a 912/// redeclaration of Old. 913/// 914/// \returns false 915bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 916 // Merge the attributes 917 MergeAttributes(New, Old, Context); 918 919 // Merge the storage class. 920 if (Old->getStorageClass() != FunctionDecl::Extern) 921 New->setStorageClass(Old->getStorageClass()); 922 923 // Merge "inline" 924 if (Old->isInline()) 925 New->setInline(true); 926 927 // If this function declaration by itself qualifies as a C99 inline 928 // definition (C99 6.7.4p6), but the previous definition did not, 929 // then the function is not a C99 inline definition. 930 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 931 New->setC99InlineDefinition(false); 932 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 933 // Mark all preceding definitions as not being C99 inline definitions. 934 for (const FunctionDecl *Prev = Old; Prev; 935 Prev = Prev->getPreviousDeclaration()) 936 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 937 } 938 939 // Merge "pure" flag. 940 if (Old->isPure()) 941 New->setPure(); 942 943 // Merge the "deleted" flag. 944 if (Old->isDeleted()) 945 New->setDeleted(); 946 947 if (getLangOptions().CPlusPlus) 948 return MergeCXXFunctionDecl(New, Old); 949 950 return false; 951} 952 953/// MergeVarDecl - We just parsed a variable 'New' which has the same name 954/// and scope as a previous declaration 'Old'. Figure out how to resolve this 955/// situation, merging decls or emitting diagnostics as appropriate. 956/// 957/// Tentative definition rules (C99 6.9.2p2) are checked by 958/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 959/// definitions here, since the initializer hasn't been attached. 960/// 961void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 962 // If either decl is invalid, make sure the new one is marked invalid and 963 // don't do any other checking. 964 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 965 return New->setInvalidDecl(); 966 967 // Verify the old decl was also a variable. 968 VarDecl *Old = dyn_cast<VarDecl>(OldD); 969 if (!Old) { 970 Diag(New->getLocation(), diag::err_redefinition_different_kind) 971 << New->getDeclName(); 972 Diag(OldD->getLocation(), diag::note_previous_definition); 973 return New->setInvalidDecl(); 974 } 975 976 MergeAttributes(New, Old, Context); 977 978 // Merge the types 979 QualType MergedT; 980 if (getLangOptions().CPlusPlus) { 981 if (Context.hasSameType(New->getType(), Old->getType())) 982 MergedT = New->getType(); 983 } else { 984 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 985 } 986 if (MergedT.isNull()) { 987 Diag(New->getLocation(), diag::err_redefinition_different_type) 988 << New->getDeclName(); 989 Diag(Old->getLocation(), diag::note_previous_definition); 990 return New->setInvalidDecl(); 991 } 992 New->setType(MergedT); 993 994 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 995 if (New->getStorageClass() == VarDecl::Static && 996 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 997 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 998 Diag(Old->getLocation(), diag::note_previous_definition); 999 return New->setInvalidDecl(); 1000 } 1001 // C99 6.2.2p4: 1002 // For an identifier declared with the storage-class specifier 1003 // extern in a scope in which a prior declaration of that 1004 // identifier is visible,23) if the prior declaration specifies 1005 // internal or external linkage, the linkage of the identifier at 1006 // the later declaration is the same as the linkage specified at 1007 // the prior declaration. If no prior declaration is visible, or 1008 // if the prior declaration specifies no linkage, then the 1009 // identifier has external linkage. 1010 if (New->hasExternalStorage() && Old->hasLinkage()) 1011 /* Okay */; 1012 else if (New->getStorageClass() != VarDecl::Static && 1013 Old->getStorageClass() == VarDecl::Static) { 1014 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1015 Diag(Old->getLocation(), diag::note_previous_definition); 1016 return New->setInvalidDecl(); 1017 } 1018 1019 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1020 1021 // FIXME: The test for external storage here seems wrong? We still 1022 // need to check for mismatches. 1023 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1024 // Don't complain about out-of-line definitions of static members. 1025 !(Old->getLexicalDeclContext()->isRecord() && 1026 !New->getLexicalDeclContext()->isRecord())) { 1027 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1028 Diag(Old->getLocation(), diag::note_previous_definition); 1029 return New->setInvalidDecl(); 1030 } 1031 1032 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1033 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1034 Diag(Old->getLocation(), diag::note_previous_definition); 1035 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1036 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1037 Diag(Old->getLocation(), diag::note_previous_definition); 1038 } 1039 1040 // Keep a chain of previous declarations. 1041 New->setPreviousDeclaration(Old); 1042} 1043 1044/// CheckFallThrough - Check that we don't fall off the end of a 1045/// Statement that should return a value. 1046/// 1047/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1048/// MaybeFallThrough iff we might or might not fall off the end and 1049/// NeverFallThrough iff we never fall off the end of the statement. We assume 1050/// that functions not marked noreturn will return. 1051Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1052 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1053 1054 // FIXME: They should never return 0, fix that, delete this code. 1055 if (cfg == 0) 1056 return NeverFallThrough; 1057 // The CFG leaves in dead things, and we don't want to dead code paths to 1058 // confuse us, so we mark all live things first. 1059 std::queue<CFGBlock*> workq; 1060 llvm::BitVector live(cfg->getNumBlockIDs()); 1061 // Prep work queue 1062 workq.push(&cfg->getEntry()); 1063 // Solve 1064 while (!workq.empty()) { 1065 CFGBlock *item = workq.front(); 1066 workq.pop(); 1067 live.set(item->getBlockID()); 1068 for (CFGBlock::succ_iterator I=item->succ_begin(), 1069 E=item->succ_end(); 1070 I != E; 1071 ++I) { 1072 if ((*I) && !live[(*I)->getBlockID()]) { 1073 live.set((*I)->getBlockID()); 1074 workq.push(*I); 1075 } 1076 } 1077 } 1078 1079 // Now we know what is live, we check the live precessors of the exit block 1080 // and look for fall through paths, being careful to ignore normal returns, 1081 // and exceptional paths. 1082 bool HasLiveReturn = false; 1083 bool HasFakeEdge = false; 1084 bool HasPlainEdge = false; 1085 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1086 E = cfg->getExit().pred_end(); 1087 I != E; 1088 ++I) { 1089 CFGBlock& B = **I; 1090 if (!live[B.getBlockID()]) 1091 continue; 1092 if (B.size() == 0) { 1093 // A labeled empty statement, or the entry block... 1094 HasPlainEdge = true; 1095 continue; 1096 } 1097 Stmt *S = B[B.size()-1]; 1098 if (isa<ReturnStmt>(S)) { 1099 HasLiveReturn = true; 1100 continue; 1101 } 1102 if (isa<ObjCAtThrowStmt>(S)) { 1103 HasFakeEdge = true; 1104 continue; 1105 } 1106 if (isa<CXXThrowExpr>(S)) { 1107 HasFakeEdge = true; 1108 continue; 1109 } 1110 bool NoReturnEdge = false; 1111 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1112 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1113 if (CEE->getType().getNoReturnAttr()) { 1114 NoReturnEdge = true; 1115 HasFakeEdge = true; 1116 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1117 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1118 if (FD->hasAttr<NoReturnAttr>()) { 1119 NoReturnEdge = true; 1120 HasFakeEdge = true; 1121 } 1122 } 1123 } 1124 } 1125 // FIXME: Add noreturn message sends. 1126 if (NoReturnEdge == false) 1127 HasPlainEdge = true; 1128 } 1129 if (!HasPlainEdge) 1130 return NeverFallThrough; 1131 if (HasFakeEdge || HasLiveReturn) 1132 return MaybeFallThrough; 1133 // This says AlwaysFallThrough for calls to functions that are not marked 1134 // noreturn, that don't return. If people would like this warning to be more 1135 // accurate, such functions should be marked as noreturn. 1136 return AlwaysFallThrough; 1137} 1138 1139/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1140/// function that should return a value. Check that we don't fall off the end 1141/// of a noreturn function. We assume that functions and blocks not marked 1142/// noreturn will return. 1143void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1144 // FIXME: Would be nice if we had a better way to control cascading errors, 1145 // but for now, avoid them. The problem is that when Parse sees: 1146 // int foo() { return a; } 1147 // The return is eaten and the Sema code sees just: 1148 // int foo() { } 1149 // which this code would then warn about. 1150 if (getDiagnostics().hasErrorOccurred()) 1151 return; 1152 bool ReturnsVoid = false; 1153 bool HasNoReturn = false; 1154 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1155 if (FD->getResultType()->isVoidType()) 1156 ReturnsVoid = true; 1157 if (FD->hasAttr<NoReturnAttr>()) 1158 HasNoReturn = true; 1159 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1160 if (MD->getResultType()->isVoidType()) 1161 ReturnsVoid = true; 1162 if (MD->hasAttr<NoReturnAttr>()) 1163 HasNoReturn = true; 1164 } 1165 1166 // Short circuit for compilation speed. 1167 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1168 == Diagnostic::Ignored || ReturnsVoid) 1169 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1170 == Diagnostic::Ignored || !HasNoReturn) 1171 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1172 == Diagnostic::Ignored || !ReturnsVoid)) 1173 return; 1174 // FIXME: Funtion try block 1175 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1176 switch (CheckFallThrough(Body)) { 1177 case MaybeFallThrough: 1178 if (HasNoReturn) 1179 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1180 else if (!ReturnsVoid) 1181 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1182 break; 1183 case AlwaysFallThrough: 1184 if (HasNoReturn) 1185 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1186 else if (!ReturnsVoid) 1187 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1188 break; 1189 case NeverFallThrough: 1190 if (ReturnsVoid) 1191 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1192 break; 1193 } 1194 } 1195} 1196 1197/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1198/// that should return a value. Check that we don't fall off the end of a 1199/// noreturn block. We assume that functions and blocks not marked noreturn 1200/// will return. 1201void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1202 // FIXME: Would be nice if we had a better way to control cascading errors, 1203 // but for now, avoid them. The problem is that when Parse sees: 1204 // int foo() { return a; } 1205 // The return is eaten and the Sema code sees just: 1206 // int foo() { } 1207 // which this code would then warn about. 1208 if (getDiagnostics().hasErrorOccurred()) 1209 return; 1210 bool ReturnsVoid = false; 1211 bool HasNoReturn = false; 1212 if (const FunctionType *FT = BlockTy->getPointeeType()->getAsFunctionType()) { 1213 if (FT->getResultType()->isVoidType()) 1214 ReturnsVoid = true; 1215 if (FT->getNoReturnAttr()) 1216 HasNoReturn = true; 1217 } 1218 1219 // Short circuit for compilation speed. 1220 if (ReturnsVoid 1221 && !HasNoReturn 1222 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1223 == Diagnostic::Ignored || !ReturnsVoid)) 1224 return; 1225 // FIXME: Funtion try block 1226 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1227 switch (CheckFallThrough(Body)) { 1228 case MaybeFallThrough: 1229 if (HasNoReturn) 1230 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1231 else if (!ReturnsVoid) 1232 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1233 break; 1234 case AlwaysFallThrough: 1235 if (HasNoReturn) 1236 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1237 else if (!ReturnsVoid) 1238 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1239 break; 1240 case NeverFallThrough: 1241 if (ReturnsVoid) 1242 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1243 break; 1244 } 1245 } 1246} 1247 1248/// CheckParmsForFunctionDef - Check that the parameters of the given 1249/// function are appropriate for the definition of a function. This 1250/// takes care of any checks that cannot be performed on the 1251/// declaration itself, e.g., that the types of each of the function 1252/// parameters are complete. 1253bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1254 bool HasInvalidParm = false; 1255 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1256 ParmVarDecl *Param = FD->getParamDecl(p); 1257 1258 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1259 // function declarator that is part of a function definition of 1260 // that function shall not have incomplete type. 1261 // 1262 // This is also C++ [dcl.fct]p6. 1263 if (!Param->isInvalidDecl() && 1264 RequireCompleteType(Param->getLocation(), Param->getType(), 1265 diag::err_typecheck_decl_incomplete_type)) { 1266 Param->setInvalidDecl(); 1267 HasInvalidParm = true; 1268 } 1269 1270 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1271 // declaration of each parameter shall include an identifier. 1272 if (Param->getIdentifier() == 0 && 1273 !Param->isImplicit() && 1274 !getLangOptions().CPlusPlus) 1275 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1276 } 1277 1278 return HasInvalidParm; 1279} 1280 1281/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1282/// no declarator (e.g. "struct foo;") is parsed. 1283Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1284 // FIXME: Error on auto/register at file scope 1285 // FIXME: Error on inline/virtual/explicit 1286 // FIXME: Error on invalid restrict 1287 // FIXME: Warn on useless __thread 1288 // FIXME: Warn on useless const/volatile 1289 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1290 // FIXME: Warn on useless attributes 1291 TagDecl *Tag = 0; 1292 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1293 DS.getTypeSpecType() == DeclSpec::TST_struct || 1294 DS.getTypeSpecType() == DeclSpec::TST_union || 1295 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1296 if (!DS.getTypeRep()) // We probably had an error 1297 return DeclPtrTy(); 1298 1299 // Note that the above type specs guarantee that the 1300 // type rep is a Decl, whereas in many of the others 1301 // it's a Type. 1302 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1303 } 1304 1305 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1306 if (!Record->getDeclName() && Record->isDefinition() && 1307 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1308 if (getLangOptions().CPlusPlus || 1309 Record->getDeclContext()->isRecord()) 1310 return BuildAnonymousStructOrUnion(S, DS, Record); 1311 1312 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1313 << DS.getSourceRange(); 1314 } 1315 1316 // Microsoft allows unnamed struct/union fields. Don't complain 1317 // about them. 1318 // FIXME: Should we support Microsoft's extensions in this area? 1319 if (Record->getDeclName() && getLangOptions().Microsoft) 1320 return DeclPtrTy::make(Tag); 1321 } 1322 1323 if (!DS.isMissingDeclaratorOk() && 1324 DS.getTypeSpecType() != DeclSpec::TST_error) { 1325 // Warn about typedefs of enums without names, since this is an 1326 // extension in both Microsoft an GNU. 1327 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1328 Tag && isa<EnumDecl>(Tag)) { 1329 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1330 << DS.getSourceRange(); 1331 return DeclPtrTy::make(Tag); 1332 } 1333 1334 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1335 << DS.getSourceRange(); 1336 return DeclPtrTy(); 1337 } 1338 1339 return DeclPtrTy::make(Tag); 1340} 1341 1342/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1343/// anonymous struct or union AnonRecord into the owning context Owner 1344/// and scope S. This routine will be invoked just after we realize 1345/// that an unnamed union or struct is actually an anonymous union or 1346/// struct, e.g., 1347/// 1348/// @code 1349/// union { 1350/// int i; 1351/// float f; 1352/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1353/// // f into the surrounding scope.x 1354/// @endcode 1355/// 1356/// This routine is recursive, injecting the names of nested anonymous 1357/// structs/unions into the owning context and scope as well. 1358bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1359 RecordDecl *AnonRecord) { 1360 bool Invalid = false; 1361 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1362 FEnd = AnonRecord->field_end(); 1363 F != FEnd; ++F) { 1364 if ((*F)->getDeclName()) { 1365 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1366 LookupOrdinaryName, true); 1367 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1368 // C++ [class.union]p2: 1369 // The names of the members of an anonymous union shall be 1370 // distinct from the names of any other entity in the 1371 // scope in which the anonymous union is declared. 1372 unsigned diagKind 1373 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1374 : diag::err_anonymous_struct_member_redecl; 1375 Diag((*F)->getLocation(), diagKind) 1376 << (*F)->getDeclName(); 1377 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1378 Invalid = true; 1379 } else { 1380 // C++ [class.union]p2: 1381 // For the purpose of name lookup, after the anonymous union 1382 // definition, the members of the anonymous union are 1383 // considered to have been defined in the scope in which the 1384 // anonymous union is declared. 1385 Owner->makeDeclVisibleInContext(*F); 1386 S->AddDecl(DeclPtrTy::make(*F)); 1387 IdResolver.AddDecl(*F); 1388 } 1389 } else if (const RecordType *InnerRecordType 1390 = (*F)->getType()->getAs<RecordType>()) { 1391 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1392 if (InnerRecord->isAnonymousStructOrUnion()) 1393 Invalid = Invalid || 1394 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1395 } 1396 } 1397 1398 return Invalid; 1399} 1400 1401/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1402/// anonymous structure or union. Anonymous unions are a C++ feature 1403/// (C++ [class.union]) and a GNU C extension; anonymous structures 1404/// are a GNU C and GNU C++ extension. 1405Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1406 RecordDecl *Record) { 1407 DeclContext *Owner = Record->getDeclContext(); 1408 1409 // Diagnose whether this anonymous struct/union is an extension. 1410 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1411 Diag(Record->getLocation(), diag::ext_anonymous_union); 1412 else if (!Record->isUnion()) 1413 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1414 1415 // C and C++ require different kinds of checks for anonymous 1416 // structs/unions. 1417 bool Invalid = false; 1418 if (getLangOptions().CPlusPlus) { 1419 const char* PrevSpec = 0; 1420 unsigned DiagID; 1421 // C++ [class.union]p3: 1422 // Anonymous unions declared in a named namespace or in the 1423 // global namespace shall be declared static. 1424 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1425 (isa<TranslationUnitDecl>(Owner) || 1426 (isa<NamespaceDecl>(Owner) && 1427 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1428 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1429 Invalid = true; 1430 1431 // Recover by adding 'static'. 1432 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1433 PrevSpec, DiagID); 1434 } 1435 // C++ [class.union]p3: 1436 // A storage class is not allowed in a declaration of an 1437 // anonymous union in a class scope. 1438 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1439 isa<RecordDecl>(Owner)) { 1440 Diag(DS.getStorageClassSpecLoc(), 1441 diag::err_anonymous_union_with_storage_spec); 1442 Invalid = true; 1443 1444 // Recover by removing the storage specifier. 1445 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1446 PrevSpec, DiagID); 1447 } 1448 1449 // C++ [class.union]p2: 1450 // The member-specification of an anonymous union shall only 1451 // define non-static data members. [Note: nested types and 1452 // functions cannot be declared within an anonymous union. ] 1453 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1454 MemEnd = Record->decls_end(); 1455 Mem != MemEnd; ++Mem) { 1456 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1457 // C++ [class.union]p3: 1458 // An anonymous union shall not have private or protected 1459 // members (clause 11). 1460 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1461 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1462 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1463 Invalid = true; 1464 } 1465 } else if ((*Mem)->isImplicit()) { 1466 // Any implicit members are fine. 1467 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1468 // This is a type that showed up in an 1469 // elaborated-type-specifier inside the anonymous struct or 1470 // union, but which actually declares a type outside of the 1471 // anonymous struct or union. It's okay. 1472 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1473 if (!MemRecord->isAnonymousStructOrUnion() && 1474 MemRecord->getDeclName()) { 1475 // This is a nested type declaration. 1476 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1477 << (int)Record->isUnion(); 1478 Invalid = true; 1479 } 1480 } else { 1481 // We have something that isn't a non-static data 1482 // member. Complain about it. 1483 unsigned DK = diag::err_anonymous_record_bad_member; 1484 if (isa<TypeDecl>(*Mem)) 1485 DK = diag::err_anonymous_record_with_type; 1486 else if (isa<FunctionDecl>(*Mem)) 1487 DK = diag::err_anonymous_record_with_function; 1488 else if (isa<VarDecl>(*Mem)) 1489 DK = diag::err_anonymous_record_with_static; 1490 Diag((*Mem)->getLocation(), DK) 1491 << (int)Record->isUnion(); 1492 Invalid = true; 1493 } 1494 } 1495 } 1496 1497 if (!Record->isUnion() && !Owner->isRecord()) { 1498 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1499 << (int)getLangOptions().CPlusPlus; 1500 Invalid = true; 1501 } 1502 1503 // Create a declaration for this anonymous struct/union. 1504 NamedDecl *Anon = 0; 1505 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1506 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1507 /*IdentifierInfo=*/0, 1508 Context.getTypeDeclType(Record), 1509 // FIXME: Type source info. 1510 /*DInfo=*/0, 1511 /*BitWidth=*/0, /*Mutable=*/false); 1512 Anon->setAccess(AS_public); 1513 if (getLangOptions().CPlusPlus) 1514 FieldCollector->Add(cast<FieldDecl>(Anon)); 1515 } else { 1516 VarDecl::StorageClass SC; 1517 switch (DS.getStorageClassSpec()) { 1518 default: assert(0 && "Unknown storage class!"); 1519 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1520 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1521 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1522 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1523 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1524 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1525 case DeclSpec::SCS_mutable: 1526 // mutable can only appear on non-static class members, so it's always 1527 // an error here 1528 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1529 Invalid = true; 1530 SC = VarDecl::None; 1531 break; 1532 } 1533 1534 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1535 /*IdentifierInfo=*/0, 1536 Context.getTypeDeclType(Record), 1537 // FIXME: Type source info. 1538 /*DInfo=*/0, 1539 SC); 1540 } 1541 Anon->setImplicit(); 1542 1543 // Add the anonymous struct/union object to the current 1544 // context. We'll be referencing this object when we refer to one of 1545 // its members. 1546 Owner->addDecl(Anon); 1547 1548 // Inject the members of the anonymous struct/union into the owning 1549 // context and into the identifier resolver chain for name lookup 1550 // purposes. 1551 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1552 Invalid = true; 1553 1554 // Mark this as an anonymous struct/union type. Note that we do not 1555 // do this until after we have already checked and injected the 1556 // members of this anonymous struct/union type, because otherwise 1557 // the members could be injected twice: once by DeclContext when it 1558 // builds its lookup table, and once by 1559 // InjectAnonymousStructOrUnionMembers. 1560 Record->setAnonymousStructOrUnion(true); 1561 1562 if (Invalid) 1563 Anon->setInvalidDecl(); 1564 1565 return DeclPtrTy::make(Anon); 1566} 1567 1568 1569/// GetNameForDeclarator - Determine the full declaration name for the 1570/// given Declarator. 1571DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1572 switch (D.getKind()) { 1573 case Declarator::DK_Abstract: 1574 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1575 return DeclarationName(); 1576 1577 case Declarator::DK_Normal: 1578 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1579 return DeclarationName(D.getIdentifier()); 1580 1581 case Declarator::DK_Constructor: { 1582 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1583 return Context.DeclarationNames.getCXXConstructorName( 1584 Context.getCanonicalType(Ty)); 1585 } 1586 1587 case Declarator::DK_Destructor: { 1588 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1589 return Context.DeclarationNames.getCXXDestructorName( 1590 Context.getCanonicalType(Ty)); 1591 } 1592 1593 case Declarator::DK_Conversion: { 1594 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1595 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1596 return Context.DeclarationNames.getCXXConversionFunctionName( 1597 Context.getCanonicalType(Ty)); 1598 } 1599 1600 case Declarator::DK_Operator: 1601 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1602 return Context.DeclarationNames.getCXXOperatorName( 1603 D.getOverloadedOperator()); 1604 } 1605 1606 assert(false && "Unknown name kind"); 1607 return DeclarationName(); 1608} 1609 1610/// isNearlyMatchingFunction - Determine whether the C++ functions 1611/// Declaration and Definition are "nearly" matching. This heuristic 1612/// is used to improve diagnostics in the case where an out-of-line 1613/// function definition doesn't match any declaration within 1614/// the class or namespace. 1615static bool isNearlyMatchingFunction(ASTContext &Context, 1616 FunctionDecl *Declaration, 1617 FunctionDecl *Definition) { 1618 if (Declaration->param_size() != Definition->param_size()) 1619 return false; 1620 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1621 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1622 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1623 1624 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1625 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1626 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1627 return false; 1628 } 1629 1630 return true; 1631} 1632 1633Sema::DeclPtrTy 1634Sema::HandleDeclarator(Scope *S, Declarator &D, 1635 MultiTemplateParamsArg TemplateParamLists, 1636 bool IsFunctionDefinition) { 1637 DeclarationName Name = GetNameForDeclarator(D); 1638 1639 // All of these full declarators require an identifier. If it doesn't have 1640 // one, the ParsedFreeStandingDeclSpec action should be used. 1641 if (!Name) { 1642 if (!D.isInvalidType()) // Reject this if we think it is valid. 1643 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1644 diag::err_declarator_need_ident) 1645 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1646 return DeclPtrTy(); 1647 } 1648 1649 // The scope passed in may not be a decl scope. Zip up the scope tree until 1650 // we find one that is. 1651 while ((S->getFlags() & Scope::DeclScope) == 0 || 1652 (S->getFlags() & Scope::TemplateParamScope) != 0) 1653 S = S->getParent(); 1654 1655 // If this is an out-of-line definition of a member of a class template 1656 // or class template partial specialization, we may need to rebuild the 1657 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1658 // for more information. 1659 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1660 // handle expressions properly. 1661 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1662 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1663 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1664 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1665 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1666 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1667 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1668 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1669 // FIXME: Preserve type source info. 1670 QualType T = GetTypeFromParser(DS.getTypeRep()); 1671 EnterDeclaratorContext(S, DC); 1672 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1673 ExitDeclaratorContext(S); 1674 if (T.isNull()) 1675 return DeclPtrTy(); 1676 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1677 } 1678 } 1679 1680 DeclContext *DC; 1681 NamedDecl *PrevDecl; 1682 NamedDecl *New; 1683 1684 DeclaratorInfo *DInfo = 0; 1685 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1686 1687 // See if this is a redefinition of a variable in the same scope. 1688 if (D.getCXXScopeSpec().isInvalid()) { 1689 DC = CurContext; 1690 PrevDecl = 0; 1691 D.setInvalidType(); 1692 } else if (!D.getCXXScopeSpec().isSet()) { 1693 LookupNameKind NameKind = LookupOrdinaryName; 1694 1695 // If the declaration we're planning to build will be a function 1696 // or object with linkage, then look for another declaration with 1697 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1698 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1699 /* Do nothing*/; 1700 else if (R->isFunctionType()) { 1701 if (CurContext->isFunctionOrMethod() || 1702 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1703 NameKind = LookupRedeclarationWithLinkage; 1704 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1705 NameKind = LookupRedeclarationWithLinkage; 1706 else if (CurContext->getLookupContext()->isTranslationUnit() && 1707 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1708 NameKind = LookupRedeclarationWithLinkage; 1709 1710 DC = CurContext; 1711 PrevDecl = LookupName(S, Name, NameKind, true, 1712 NameKind == LookupRedeclarationWithLinkage, 1713 D.getIdentifierLoc()); 1714 } else { // Something like "int foo::x;" 1715 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1716 1717 if (!DC) { 1718 // If we could not compute the declaration context, it's because the 1719 // declaration context is dependent but does not refer to a class, 1720 // class template, or class template partial specialization. Complain 1721 // and return early, to avoid the coming semantic disaster. 1722 Diag(D.getIdentifierLoc(), 1723 diag::err_template_qualified_declarator_no_match) 1724 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1725 << D.getCXXScopeSpec().getRange(); 1726 return DeclPtrTy(); 1727 } 1728 1729 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1730 1731 // C++ 7.3.1.2p2: 1732 // Members (including explicit specializations of templates) of a named 1733 // namespace can also be defined outside that namespace by explicit 1734 // qualification of the name being defined, provided that the entity being 1735 // defined was already declared in the namespace and the definition appears 1736 // after the point of declaration in a namespace that encloses the 1737 // declarations namespace. 1738 // 1739 // Note that we only check the context at this point. We don't yet 1740 // have enough information to make sure that PrevDecl is actually 1741 // the declaration we want to match. For example, given: 1742 // 1743 // class X { 1744 // void f(); 1745 // void f(float); 1746 // }; 1747 // 1748 // void X::f(int) { } // ill-formed 1749 // 1750 // In this case, PrevDecl will point to the overload set 1751 // containing the two f's declared in X, but neither of them 1752 // matches. 1753 1754 // First check whether we named the global scope. 1755 if (isa<TranslationUnitDecl>(DC)) { 1756 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1757 << Name << D.getCXXScopeSpec().getRange(); 1758 } else if (!CurContext->Encloses(DC)) { 1759 // The qualifying scope doesn't enclose the original declaration. 1760 // Emit diagnostic based on current scope. 1761 SourceLocation L = D.getIdentifierLoc(); 1762 SourceRange R = D.getCXXScopeSpec().getRange(); 1763 if (isa<FunctionDecl>(CurContext)) 1764 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1765 else 1766 Diag(L, diag::err_invalid_declarator_scope) 1767 << Name << cast<NamedDecl>(DC) << R; 1768 D.setInvalidType(); 1769 } 1770 } 1771 1772 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1773 // Maybe we will complain about the shadowed template parameter. 1774 if (!D.isInvalidType()) 1775 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1776 D.setInvalidType(); 1777 1778 // Just pretend that we didn't see the previous declaration. 1779 PrevDecl = 0; 1780 } 1781 1782 // In C++, the previous declaration we find might be a tag type 1783 // (class or enum). In this case, the new declaration will hide the 1784 // tag type. Note that this does does not apply if we're declaring a 1785 // typedef (C++ [dcl.typedef]p4). 1786 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1787 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1788 PrevDecl = 0; 1789 1790 bool Redeclaration = false; 1791 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1792 if (TemplateParamLists.size()) { 1793 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1794 return DeclPtrTy(); 1795 } 1796 1797 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1798 } else if (R->isFunctionType()) { 1799 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1800 move(TemplateParamLists), 1801 IsFunctionDefinition, Redeclaration); 1802 } else { 1803 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1804 move(TemplateParamLists), 1805 Redeclaration); 1806 } 1807 1808 if (New == 0) 1809 return DeclPtrTy(); 1810 1811 // If this has an identifier and is not an invalid redeclaration, 1812 // add it to the scope stack. 1813 if (Name && !(Redeclaration && New->isInvalidDecl())) 1814 PushOnScopeChains(New, S); 1815 1816 return DeclPtrTy::make(New); 1817} 1818 1819/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1820/// types into constant array types in certain situations which would otherwise 1821/// be errors (for GCC compatibility). 1822static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1823 ASTContext &Context, 1824 bool &SizeIsNegative) { 1825 // This method tries to turn a variable array into a constant 1826 // array even when the size isn't an ICE. This is necessary 1827 // for compatibility with code that depends on gcc's buggy 1828 // constant expression folding, like struct {char x[(int)(char*)2];} 1829 SizeIsNegative = false; 1830 1831 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1832 QualType Pointee = PTy->getPointeeType(); 1833 QualType FixedType = 1834 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1835 if (FixedType.isNull()) return FixedType; 1836 FixedType = Context.getPointerType(FixedType); 1837 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1838 return FixedType; 1839 } 1840 1841 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1842 if (!VLATy) 1843 return QualType(); 1844 // FIXME: We should probably handle this case 1845 if (VLATy->getElementType()->isVariablyModifiedType()) 1846 return QualType(); 1847 1848 Expr::EvalResult EvalResult; 1849 if (!VLATy->getSizeExpr() || 1850 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1851 !EvalResult.Val.isInt()) 1852 return QualType(); 1853 1854 llvm::APSInt &Res = EvalResult.Val.getInt(); 1855 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1856 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1857 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1858 // so as to transfer ownership to the ConstantArrayWithExpr. 1859 // Alternatively, we could "clone" it (how?). 1860 // Since we don't know how to do things above, we just use the 1861 // very same Expr*. 1862 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1863 Res, ArySizeExpr, 1864 ArrayType::Normal, 0, 1865 VLATy->getBracketsRange()); 1866 } 1867 1868 SizeIsNegative = true; 1869 return QualType(); 1870} 1871 1872/// \brief Register the given locally-scoped external C declaration so 1873/// that it can be found later for redeclarations 1874void 1875Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1876 Scope *S) { 1877 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1878 "Decl is not a locally-scoped decl!"); 1879 // Note that we have a locally-scoped external with this name. 1880 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1881 1882 if (!PrevDecl) 1883 return; 1884 1885 // If there was a previous declaration of this variable, it may be 1886 // in our identifier chain. Update the identifier chain with the new 1887 // declaration. 1888 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1889 // The previous declaration was found on the identifer resolver 1890 // chain, so remove it from its scope. 1891 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1892 S = S->getParent(); 1893 1894 if (S) 1895 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1896 } 1897} 1898 1899/// \brief Diagnose function specifiers on a declaration of an identifier that 1900/// does not identify a function. 1901void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1902 // FIXME: We should probably indicate the identifier in question to avoid 1903 // confusion for constructs like "inline int a(), b;" 1904 if (D.getDeclSpec().isInlineSpecified()) 1905 Diag(D.getDeclSpec().getInlineSpecLoc(), 1906 diag::err_inline_non_function); 1907 1908 if (D.getDeclSpec().isVirtualSpecified()) 1909 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1910 diag::err_virtual_non_function); 1911 1912 if (D.getDeclSpec().isExplicitSpecified()) 1913 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1914 diag::err_explicit_non_function); 1915} 1916 1917NamedDecl* 1918Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1919 QualType R, DeclaratorInfo *DInfo, 1920 Decl* PrevDecl, bool &Redeclaration) { 1921 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1922 if (D.getCXXScopeSpec().isSet()) { 1923 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1924 << D.getCXXScopeSpec().getRange(); 1925 D.setInvalidType(); 1926 // Pretend we didn't see the scope specifier. 1927 DC = 0; 1928 } 1929 1930 if (getLangOptions().CPlusPlus) { 1931 // Check that there are no default arguments (C++ only). 1932 CheckExtraCXXDefaultArguments(D); 1933 } 1934 1935 DiagnoseFunctionSpecifiers(D); 1936 1937 if (D.getDeclSpec().isThreadSpecified()) 1938 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1939 1940 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1941 if (!NewTD) return 0; 1942 1943 if (D.isInvalidType()) 1944 NewTD->setInvalidDecl(); 1945 1946 // Handle attributes prior to checking for duplicates in MergeVarDecl 1947 ProcessDeclAttributes(S, NewTD, D); 1948 // Merge the decl with the existing one if appropriate. If the decl is 1949 // in an outer scope, it isn't the same thing. 1950 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1951 Redeclaration = true; 1952 MergeTypeDefDecl(NewTD, PrevDecl); 1953 } 1954 1955 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1956 // then it shall have block scope. 1957 QualType T = NewTD->getUnderlyingType(); 1958 if (T->isVariablyModifiedType()) { 1959 CurFunctionNeedsScopeChecking = true; 1960 1961 if (S->getFnParent() == 0) { 1962 bool SizeIsNegative; 1963 QualType FixedTy = 1964 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1965 if (!FixedTy.isNull()) { 1966 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1967 NewTD->setUnderlyingType(FixedTy); 1968 } else { 1969 if (SizeIsNegative) 1970 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1971 else if (T->isVariableArrayType()) 1972 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1973 else 1974 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1975 NewTD->setInvalidDecl(); 1976 } 1977 } 1978 } 1979 1980 // If this is the C FILE type, notify the AST context. 1981 if (IdentifierInfo *II = NewTD->getIdentifier()) 1982 if (!NewTD->isInvalidDecl() && 1983 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1984 if (II->isStr("FILE")) 1985 Context.setFILEDecl(NewTD); 1986 else if (II->isStr("jmp_buf")) 1987 Context.setjmp_bufDecl(NewTD); 1988 else if (II->isStr("sigjmp_buf")) 1989 Context.setsigjmp_bufDecl(NewTD); 1990 } 1991 1992 return NewTD; 1993} 1994 1995/// \brief Determines whether the given declaration is an out-of-scope 1996/// previous declaration. 1997/// 1998/// This routine should be invoked when name lookup has found a 1999/// previous declaration (PrevDecl) that is not in the scope where a 2000/// new declaration by the same name is being introduced. If the new 2001/// declaration occurs in a local scope, previous declarations with 2002/// linkage may still be considered previous declarations (C99 2003/// 6.2.2p4-5, C++ [basic.link]p6). 2004/// 2005/// \param PrevDecl the previous declaration found by name 2006/// lookup 2007/// 2008/// \param DC the context in which the new declaration is being 2009/// declared. 2010/// 2011/// \returns true if PrevDecl is an out-of-scope previous declaration 2012/// for a new delcaration with the same name. 2013static bool 2014isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2015 ASTContext &Context) { 2016 if (!PrevDecl) 2017 return 0; 2018 2019 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2020 // case we need to check each of the overloaded functions. 2021 if (!PrevDecl->hasLinkage()) 2022 return false; 2023 2024 if (Context.getLangOptions().CPlusPlus) { 2025 // C++ [basic.link]p6: 2026 // If there is a visible declaration of an entity with linkage 2027 // having the same name and type, ignoring entities declared 2028 // outside the innermost enclosing namespace scope, the block 2029 // scope declaration declares that same entity and receives the 2030 // linkage of the previous declaration. 2031 DeclContext *OuterContext = DC->getLookupContext(); 2032 if (!OuterContext->isFunctionOrMethod()) 2033 // This rule only applies to block-scope declarations. 2034 return false; 2035 else { 2036 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2037 if (PrevOuterContext->isRecord()) 2038 // We found a member function: ignore it. 2039 return false; 2040 else { 2041 // Find the innermost enclosing namespace for the new and 2042 // previous declarations. 2043 while (!OuterContext->isFileContext()) 2044 OuterContext = OuterContext->getParent(); 2045 while (!PrevOuterContext->isFileContext()) 2046 PrevOuterContext = PrevOuterContext->getParent(); 2047 2048 // The previous declaration is in a different namespace, so it 2049 // isn't the same function. 2050 if (OuterContext->getPrimaryContext() != 2051 PrevOuterContext->getPrimaryContext()) 2052 return false; 2053 } 2054 } 2055 } 2056 2057 return true; 2058} 2059 2060NamedDecl* 2061Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2062 QualType R, DeclaratorInfo *DInfo, 2063 NamedDecl* PrevDecl, 2064 MultiTemplateParamsArg TemplateParamLists, 2065 bool &Redeclaration) { 2066 DeclarationName Name = GetNameForDeclarator(D); 2067 2068 // Check that there are no default arguments (C++ only). 2069 if (getLangOptions().CPlusPlus) 2070 CheckExtraCXXDefaultArguments(D); 2071 2072 VarDecl *NewVD; 2073 VarDecl::StorageClass SC; 2074 switch (D.getDeclSpec().getStorageClassSpec()) { 2075 default: assert(0 && "Unknown storage class!"); 2076 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2077 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2078 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2079 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2080 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2081 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2082 case DeclSpec::SCS_mutable: 2083 // mutable can only appear on non-static class members, so it's always 2084 // an error here 2085 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2086 D.setInvalidType(); 2087 SC = VarDecl::None; 2088 break; 2089 } 2090 2091 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2092 if (!II) { 2093 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2094 << Name.getAsString(); 2095 return 0; 2096 } 2097 2098 DiagnoseFunctionSpecifiers(D); 2099 2100 if (!DC->isRecord() && S->getFnParent() == 0) { 2101 // C99 6.9p2: The storage-class specifiers auto and register shall not 2102 // appear in the declaration specifiers in an external declaration. 2103 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2104 2105 // If this is a register variable with an asm label specified, then this 2106 // is a GNU extension. 2107 if (SC == VarDecl::Register && D.getAsmLabel()) 2108 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2109 else 2110 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2111 D.setInvalidType(); 2112 } 2113 } 2114 if (DC->isRecord() && !CurContext->isRecord()) { 2115 // This is an out-of-line definition of a static data member. 2116 if (SC == VarDecl::Static) { 2117 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2118 diag::err_static_out_of_line) 2119 << CodeModificationHint::CreateRemoval( 2120 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2121 } else if (SC == VarDecl::None) 2122 SC = VarDecl::Static; 2123 } 2124 if (SC == VarDecl::Static) { 2125 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2126 if (RD->isLocalClass()) 2127 Diag(D.getIdentifierLoc(), 2128 diag::err_static_data_member_not_allowed_in_local_class) 2129 << Name << RD->getDeclName(); 2130 } 2131 } 2132 2133 // Match up the template parameter lists with the scope specifier, then 2134 // determine whether we have a template or a template specialization. 2135 if (TemplateParameterList *TemplateParams 2136 = MatchTemplateParametersToScopeSpecifier( 2137 D.getDeclSpec().getSourceRange().getBegin(), 2138 D.getCXXScopeSpec(), 2139 (TemplateParameterList**)TemplateParamLists.get(), 2140 TemplateParamLists.size())) { 2141 if (TemplateParams->size() > 0) { 2142 // There is no such thing as a variable template. 2143 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2144 << II 2145 << SourceRange(TemplateParams->getTemplateLoc(), 2146 TemplateParams->getRAngleLoc()); 2147 return 0; 2148 } else { 2149 // There is an extraneous 'template<>' for this variable. Complain 2150 // about it, but allow the declaration of the variable. 2151 Diag(TemplateParams->getTemplateLoc(), 2152 diag::err_template_variable_noparams) 2153 << II 2154 << SourceRange(TemplateParams->getTemplateLoc(), 2155 TemplateParams->getRAngleLoc()); 2156 } 2157 } 2158 2159 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2160 II, R, DInfo, SC); 2161 2162 if (D.isInvalidType()) 2163 NewVD->setInvalidDecl(); 2164 2165 if (D.getDeclSpec().isThreadSpecified()) { 2166 if (NewVD->hasLocalStorage()) 2167 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2168 else if (!Context.Target.isTLSSupported()) 2169 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2170 else 2171 NewVD->setThreadSpecified(true); 2172 } 2173 2174 // Set the lexical context. If the declarator has a C++ scope specifier, the 2175 // lexical context will be different from the semantic context. 2176 NewVD->setLexicalDeclContext(CurContext); 2177 2178 // Handle attributes prior to checking for duplicates in MergeVarDecl 2179 ProcessDeclAttributes(S, NewVD, D); 2180 2181 // Handle GNU asm-label extension (encoded as an attribute). 2182 if (Expr *E = (Expr*) D.getAsmLabel()) { 2183 // The parser guarantees this is a string. 2184 StringLiteral *SE = cast<StringLiteral>(E); 2185 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2186 SE->getByteLength()))); 2187 } 2188 2189 // If name lookup finds a previous declaration that is not in the 2190 // same scope as the new declaration, this may still be an 2191 // acceptable redeclaration. 2192 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2193 !(NewVD->hasLinkage() && 2194 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2195 PrevDecl = 0; 2196 2197 // Merge the decl with the existing one if appropriate. 2198 if (PrevDecl) { 2199 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2200 // The user tried to define a non-static data member 2201 // out-of-line (C++ [dcl.meaning]p1). 2202 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2203 << D.getCXXScopeSpec().getRange(); 2204 PrevDecl = 0; 2205 NewVD->setInvalidDecl(); 2206 } 2207 } else if (D.getCXXScopeSpec().isSet()) { 2208 // No previous declaration in the qualifying scope. 2209 NestedNameSpecifier *NNS = 2210 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2211 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2212 D.getCXXScopeSpec().getRange()); 2213 NewVD->setInvalidDecl(); 2214 } 2215 2216 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2217 2218 // attributes declared post-definition are currently ignored 2219 if (PrevDecl) { 2220 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2221 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2222 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2223 Diag(Def->getLocation(), diag::note_previous_definition); 2224 } 2225 } 2226 2227 // If this is a locally-scoped extern C variable, update the map of 2228 // such variables. 2229 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 2230 !NewVD->isInvalidDecl()) 2231 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2232 2233 return NewVD; 2234} 2235 2236/// \brief Perform semantic checking on a newly-created variable 2237/// declaration. 2238/// 2239/// This routine performs all of the type-checking required for a 2240/// variable declaration once it has been built. It is used both to 2241/// check variables after they have been parsed and their declarators 2242/// have been translated into a declaration, and to check variables 2243/// that have been instantiated from a template. 2244/// 2245/// Sets NewVD->isInvalidDecl() if an error was encountered. 2246void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2247 bool &Redeclaration) { 2248 // If the decl is already known invalid, don't check it. 2249 if (NewVD->isInvalidDecl()) 2250 return; 2251 2252 QualType T = NewVD->getType(); 2253 2254 if (T->isObjCInterfaceType()) { 2255 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2256 return NewVD->setInvalidDecl(); 2257 } 2258 2259 // The variable can not have an abstract class type. 2260 if (RequireNonAbstractType(NewVD->getLocation(), T, 2261 diag::err_abstract_type_in_decl, 2262 AbstractVariableType)) 2263 return NewVD->setInvalidDecl(); 2264 2265 // Emit an error if an address space was applied to decl with local storage. 2266 // This includes arrays of objects with address space qualifiers, but not 2267 // automatic variables that point to other address spaces. 2268 // ISO/IEC TR 18037 S5.1.2 2269 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2270 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2271 return NewVD->setInvalidDecl(); 2272 } 2273 2274 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2275 && !NewVD->hasAttr<BlocksAttr>()) 2276 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2277 2278 bool isVM = T->isVariablyModifiedType(); 2279 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2280 NewVD->hasAttr<BlocksAttr>()) 2281 CurFunctionNeedsScopeChecking = true; 2282 2283 if ((isVM && NewVD->hasLinkage()) || 2284 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2285 bool SizeIsNegative; 2286 QualType FixedTy = 2287 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2288 2289 if (FixedTy.isNull() && T->isVariableArrayType()) { 2290 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2291 // FIXME: This won't give the correct result for 2292 // int a[10][n]; 2293 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2294 2295 if (NewVD->isFileVarDecl()) 2296 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2297 << SizeRange; 2298 else if (NewVD->getStorageClass() == VarDecl::Static) 2299 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2300 << SizeRange; 2301 else 2302 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2303 << SizeRange; 2304 return NewVD->setInvalidDecl(); 2305 } 2306 2307 if (FixedTy.isNull()) { 2308 if (NewVD->isFileVarDecl()) 2309 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2310 else 2311 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2312 return NewVD->setInvalidDecl(); 2313 } 2314 2315 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2316 NewVD->setType(FixedTy); 2317 } 2318 2319 if (!PrevDecl && NewVD->isExternC(Context)) { 2320 // Since we did not find anything by this name and we're declaring 2321 // an extern "C" variable, look for a non-visible extern "C" 2322 // declaration with the same name. 2323 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2324 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2325 if (Pos != LocallyScopedExternalDecls.end()) 2326 PrevDecl = Pos->second; 2327 } 2328 2329 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2330 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2331 << T; 2332 return NewVD->setInvalidDecl(); 2333 } 2334 2335 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2336 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2337 return NewVD->setInvalidDecl(); 2338 } 2339 2340 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2341 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2342 return NewVD->setInvalidDecl(); 2343 } 2344 2345 if (PrevDecl) { 2346 Redeclaration = true; 2347 MergeVarDecl(NewVD, PrevDecl); 2348 } 2349} 2350 2351static bool isUsingDecl(Decl *D) { 2352 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2353} 2354 2355NamedDecl* 2356Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2357 QualType R, DeclaratorInfo *DInfo, 2358 NamedDecl* PrevDecl, 2359 MultiTemplateParamsArg TemplateParamLists, 2360 bool IsFunctionDefinition, bool &Redeclaration) { 2361 assert(R.getTypePtr()->isFunctionType()); 2362 2363 DeclarationName Name = GetNameForDeclarator(D); 2364 FunctionDecl::StorageClass SC = FunctionDecl::None; 2365 switch (D.getDeclSpec().getStorageClassSpec()) { 2366 default: assert(0 && "Unknown storage class!"); 2367 case DeclSpec::SCS_auto: 2368 case DeclSpec::SCS_register: 2369 case DeclSpec::SCS_mutable: 2370 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2371 diag::err_typecheck_sclass_func); 2372 D.setInvalidType(); 2373 break; 2374 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2375 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2376 case DeclSpec::SCS_static: { 2377 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2378 // C99 6.7.1p5: 2379 // The declaration of an identifier for a function that has 2380 // block scope shall have no explicit storage-class specifier 2381 // other than extern 2382 // See also (C++ [dcl.stc]p4). 2383 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2384 diag::err_static_block_func); 2385 SC = FunctionDecl::None; 2386 } else 2387 SC = FunctionDecl::Static; 2388 break; 2389 } 2390 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2391 } 2392 2393 if (D.getDeclSpec().isThreadSpecified()) 2394 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2395 2396 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2397 bool isInline = D.getDeclSpec().isInlineSpecified(); 2398 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2399 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2400 2401 // Check that the return type is not an abstract class type. 2402 // For record types, this is done by the AbstractClassUsageDiagnoser once 2403 // the class has been completely parsed. 2404 if (!DC->isRecord() && 2405 RequireNonAbstractType(D.getIdentifierLoc(), 2406 R->getAsFunctionType()->getResultType(), 2407 diag::err_abstract_type_in_decl, 2408 AbstractReturnType)) 2409 D.setInvalidType(); 2410 2411 // Do not allow returning a objc interface by-value. 2412 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2413 Diag(D.getIdentifierLoc(), 2414 diag::err_object_cannot_be_passed_returned_by_value) << 0 2415 << R->getAsFunctionType()->getResultType(); 2416 D.setInvalidType(); 2417 } 2418 2419 bool isVirtualOkay = false; 2420 FunctionDecl *NewFD; 2421 2422 if (isFriend) { 2423 // DC is the namespace in which the function is being declared. 2424 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2425 "friend function being created in a non-namespace context"); 2426 2427 // C++ [class.friend]p5 2428 // A function can be defined in a friend declaration of a 2429 // class . . . . Such a function is implicitly inline. 2430 isInline |= IsFunctionDefinition; 2431 } 2432 2433 if (D.getKind() == Declarator::DK_Constructor) { 2434 // This is a C++ constructor declaration. 2435 assert(DC->isRecord() && 2436 "Constructors can only be declared in a member context"); 2437 2438 R = CheckConstructorDeclarator(D, R, SC); 2439 2440 // Create the new declaration 2441 NewFD = CXXConstructorDecl::Create(Context, 2442 cast<CXXRecordDecl>(DC), 2443 D.getIdentifierLoc(), Name, R, DInfo, 2444 isExplicit, isInline, 2445 /*isImplicitlyDeclared=*/false); 2446 } else if (D.getKind() == Declarator::DK_Destructor) { 2447 // This is a C++ destructor declaration. 2448 if (DC->isRecord()) { 2449 R = CheckDestructorDeclarator(D, SC); 2450 2451 NewFD = CXXDestructorDecl::Create(Context, 2452 cast<CXXRecordDecl>(DC), 2453 D.getIdentifierLoc(), Name, R, 2454 isInline, 2455 /*isImplicitlyDeclared=*/false); 2456 2457 isVirtualOkay = true; 2458 } else { 2459 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2460 2461 // Create a FunctionDecl to satisfy the function definition parsing 2462 // code path. 2463 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2464 Name, R, DInfo, SC, isInline, 2465 /*hasPrototype=*/true); 2466 D.setInvalidType(); 2467 } 2468 } else if (D.getKind() == Declarator::DK_Conversion) { 2469 if (!DC->isRecord()) { 2470 Diag(D.getIdentifierLoc(), 2471 diag::err_conv_function_not_member); 2472 return 0; 2473 } 2474 2475 CheckConversionDeclarator(D, R, SC); 2476 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2477 D.getIdentifierLoc(), Name, R, DInfo, 2478 isInline, isExplicit); 2479 2480 isVirtualOkay = true; 2481 } else if (DC->isRecord()) { 2482 // If the of the function is the same as the name of the record, then this 2483 // must be an invalid constructor that has a return type. 2484 // (The parser checks for a return type and makes the declarator a 2485 // constructor if it has no return type). 2486 // must have an invalid constructor that has a return type 2487 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2488 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2489 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2490 << SourceRange(D.getIdentifierLoc()); 2491 return 0; 2492 } 2493 2494 // This is a C++ method declaration. 2495 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2496 D.getIdentifierLoc(), Name, R, DInfo, 2497 (SC == FunctionDecl::Static), isInline); 2498 2499 isVirtualOkay = (SC != FunctionDecl::Static); 2500 } else { 2501 // Determine whether the function was written with a 2502 // prototype. This true when: 2503 // - we're in C++ (where every function has a prototype), 2504 // - there is a prototype in the declarator, or 2505 // - the type R of the function is some kind of typedef or other reference 2506 // to a type name (which eventually refers to a function type). 2507 bool HasPrototype = 2508 getLangOptions().CPlusPlus || 2509 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2510 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2511 2512 NewFD = FunctionDecl::Create(Context, DC, 2513 D.getIdentifierLoc(), 2514 Name, R, DInfo, SC, isInline, HasPrototype); 2515 } 2516 2517 if (D.isInvalidType()) 2518 NewFD->setInvalidDecl(); 2519 2520 // Set the lexical context. If the declarator has a C++ 2521 // scope specifier, or is the object of a friend declaration, the 2522 // lexical context will be different from the semantic context. 2523 NewFD->setLexicalDeclContext(CurContext); 2524 2525 if (isFriend) 2526 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2527 2528 // Match up the template parameter lists with the scope specifier, then 2529 // determine whether we have a template or a template specialization. 2530 FunctionTemplateDecl *FunctionTemplate = 0; 2531 if (TemplateParameterList *TemplateParams 2532 = MatchTemplateParametersToScopeSpecifier( 2533 D.getDeclSpec().getSourceRange().getBegin(), 2534 D.getCXXScopeSpec(), 2535 (TemplateParameterList**)TemplateParamLists.get(), 2536 TemplateParamLists.size())) { 2537 if (TemplateParams->size() > 0) { 2538 // This is a function template 2539 2540 // Check that we can declare a template here. 2541 if (CheckTemplateDeclScope(S, TemplateParams)) 2542 return 0; 2543 2544 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2545 NewFD->getLocation(), 2546 Name, TemplateParams, 2547 NewFD); 2548 FunctionTemplate->setLexicalDeclContext(CurContext); 2549 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2550 } else { 2551 // FIXME: Handle function template specializations 2552 } 2553 2554 // FIXME: Free this memory properly. 2555 TemplateParamLists.release(); 2556 } 2557 2558 // C++ [dcl.fct.spec]p5: 2559 // The virtual specifier shall only be used in declarations of 2560 // nonstatic class member functions that appear within a 2561 // member-specification of a class declaration; see 10.3. 2562 // 2563 if (isVirtual && !NewFD->isInvalidDecl()) { 2564 if (!isVirtualOkay) { 2565 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2566 diag::err_virtual_non_function); 2567 } else if (!CurContext->isRecord()) { 2568 // 'virtual' was specified outside of the class. 2569 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2570 << CodeModificationHint::CreateRemoval( 2571 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2572 } else { 2573 // Okay: Add virtual to the method. 2574 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2575 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2576 CurClass->setAggregate(false); 2577 CurClass->setPOD(false); 2578 CurClass->setEmpty(false); 2579 CurClass->setPolymorphic(true); 2580 CurClass->setHasTrivialConstructor(false); 2581 CurClass->setHasTrivialCopyConstructor(false); 2582 CurClass->setHasTrivialCopyAssignment(false); 2583 } 2584 } 2585 2586 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2587 // Look for virtual methods in base classes that this method might override. 2588 2589 BasePaths Paths; 2590 if (LookupInBases(cast<CXXRecordDecl>(DC), 2591 MemberLookupCriteria(NewMD), Paths)) { 2592 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2593 E = Paths.found_decls_end(); I != E; ++I) { 2594 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2595 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2596 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2597 NewMD->addOverriddenMethod(OldMD); 2598 } 2599 } 2600 } 2601 } 2602 2603 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2604 !CurContext->isRecord()) { 2605 // C++ [class.static]p1: 2606 // A data or function member of a class may be declared static 2607 // in a class definition, in which case it is a static member of 2608 // the class. 2609 2610 // Complain about the 'static' specifier if it's on an out-of-line 2611 // member function definition. 2612 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2613 diag::err_static_out_of_line) 2614 << CodeModificationHint::CreateRemoval( 2615 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2616 } 2617 2618 // Handle GNU asm-label extension (encoded as an attribute). 2619 if (Expr *E = (Expr*) D.getAsmLabel()) { 2620 // The parser guarantees this is a string. 2621 StringLiteral *SE = cast<StringLiteral>(E); 2622 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2623 SE->getByteLength()))); 2624 } 2625 2626 // Copy the parameter declarations from the declarator D to the function 2627 // declaration NewFD, if they are available. First scavenge them into Params. 2628 llvm::SmallVector<ParmVarDecl*, 16> Params; 2629 if (D.getNumTypeObjects() > 0) { 2630 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2631 2632 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2633 // function that takes no arguments, not a function that takes a 2634 // single void argument. 2635 // We let through "const void" here because Sema::GetTypeForDeclarator 2636 // already checks for that case. 2637 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2638 FTI.ArgInfo[0].Param && 2639 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2640 // Empty arg list, don't push any params. 2641 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2642 2643 // In C++, the empty parameter-type-list must be spelled "void"; a 2644 // typedef of void is not permitted. 2645 if (getLangOptions().CPlusPlus && 2646 Param->getType().getUnqualifiedType() != Context.VoidTy) 2647 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2648 // FIXME: Leaks decl? 2649 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2650 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2651 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2652 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2653 Param->setDeclContext(NewFD); 2654 Params.push_back(Param); 2655 } 2656 } 2657 2658 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2659 // When we're declaring a function with a typedef, typeof, etc as in the 2660 // following example, we'll need to synthesize (unnamed) 2661 // parameters for use in the declaration. 2662 // 2663 // @code 2664 // typedef void fn(int); 2665 // fn f; 2666 // @endcode 2667 2668 // Synthesize a parameter for each argument type. 2669 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2670 AE = FT->arg_type_end(); AI != AE; ++AI) { 2671 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2672 SourceLocation(), 0, 2673 *AI, /*DInfo=*/0, 2674 VarDecl::None, 0); 2675 Param->setImplicit(); 2676 Params.push_back(Param); 2677 } 2678 } else { 2679 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2680 "Should not need args for typedef of non-prototype fn"); 2681 } 2682 // Finally, we know we have the right number of parameters, install them. 2683 NewFD->setParams(Context, Params.data(), Params.size()); 2684 2685 // If name lookup finds a previous declaration that is not in the 2686 // same scope as the new declaration, this may still be an 2687 // acceptable redeclaration. 2688 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2689 !(NewFD->hasLinkage() && 2690 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2691 PrevDecl = 0; 2692 2693 // Perform semantic checking on the function declaration. 2694 bool OverloadableAttrRequired = false; // FIXME: HACK! 2695 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2696 /*FIXME:*/OverloadableAttrRequired); 2697 2698 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2699 // An out-of-line member function declaration must also be a 2700 // definition (C++ [dcl.meaning]p1). 2701 if (!IsFunctionDefinition && !isFriend) { 2702 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2703 << D.getCXXScopeSpec().getRange(); 2704 NewFD->setInvalidDecl(); 2705 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2706 // The user tried to provide an out-of-line definition for a 2707 // function that is a member of a class or namespace, but there 2708 // was no such member function declared (C++ [class.mfct]p2, 2709 // C++ [namespace.memdef]p2). For example: 2710 // 2711 // class X { 2712 // void f() const; 2713 // }; 2714 // 2715 // void X::f() { } // ill-formed 2716 // 2717 // Complain about this problem, and attempt to suggest close 2718 // matches (e.g., those that differ only in cv-qualifiers and 2719 // whether the parameter types are references). 2720 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2721 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2722 NewFD->setInvalidDecl(); 2723 2724 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2725 true); 2726 assert(!Prev.isAmbiguous() && 2727 "Cannot have an ambiguity in previous-declaration lookup"); 2728 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2729 Func != FuncEnd; ++Func) { 2730 if (isa<FunctionDecl>(*Func) && 2731 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2732 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2733 } 2734 2735 PrevDecl = 0; 2736 } 2737 } 2738 2739 // Handle attributes. We need to have merged decls when handling attributes 2740 // (for example to check for conflicts, etc). 2741 // FIXME: This needs to happen before we merge declarations. Then, 2742 // let attribute merging cope with attribute conflicts. 2743 ProcessDeclAttributes(S, NewFD, D); 2744 2745 // attributes declared post-definition are currently ignored 2746 if (Redeclaration && PrevDecl) { 2747 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2748 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2749 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2750 Diag(Def->getLocation(), diag::note_previous_definition); 2751 } 2752 } 2753 2754 AddKnownFunctionAttributes(NewFD); 2755 2756 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2757 // If a function name is overloadable in C, then every function 2758 // with that name must be marked "overloadable". 2759 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2760 << Redeclaration << NewFD; 2761 if (PrevDecl) 2762 Diag(PrevDecl->getLocation(), 2763 diag::note_attribute_overloadable_prev_overload); 2764 NewFD->addAttr(::new (Context) OverloadableAttr()); 2765 } 2766 2767 // If this is a locally-scoped extern C function, update the 2768 // map of such names. 2769 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2770 && !NewFD->isInvalidDecl()) 2771 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2772 2773 // Set this FunctionDecl's range up to the right paren. 2774 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2775 2776 if (FunctionTemplate && NewFD->isInvalidDecl()) 2777 FunctionTemplate->setInvalidDecl(); 2778 2779 if (FunctionTemplate) 2780 return FunctionTemplate; 2781 2782 return NewFD; 2783} 2784 2785/// \brief Perform semantic checking of a new function declaration. 2786/// 2787/// Performs semantic analysis of the new function declaration 2788/// NewFD. This routine performs all semantic checking that does not 2789/// require the actual declarator involved in the declaration, and is 2790/// used both for the declaration of functions as they are parsed 2791/// (called via ActOnDeclarator) and for the declaration of functions 2792/// that have been instantiated via C++ template instantiation (called 2793/// via InstantiateDecl). 2794/// 2795/// This sets NewFD->isInvalidDecl() to true if there was an error. 2796void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2797 bool &Redeclaration, 2798 bool &OverloadableAttrRequired) { 2799 // If NewFD is already known erroneous, don't do any of this checking. 2800 if (NewFD->isInvalidDecl()) 2801 return; 2802 2803 if (NewFD->getResultType()->isVariablyModifiedType()) { 2804 // Functions returning a variably modified type violate C99 6.7.5.2p2 2805 // because all functions have linkage. 2806 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2807 return NewFD->setInvalidDecl(); 2808 } 2809 2810 if (NewFD->isMain(Context)) CheckMain(NewFD); 2811 2812 // Semantic checking for this function declaration (in isolation). 2813 if (getLangOptions().CPlusPlus) { 2814 // C++-specific checks. 2815 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2816 CheckConstructor(Constructor); 2817 } else if (isa<CXXDestructorDecl>(NewFD)) { 2818 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2819 QualType ClassType = Context.getTypeDeclType(Record); 2820 if (!ClassType->isDependentType()) { 2821 DeclarationName Name 2822 = Context.DeclarationNames.getCXXDestructorName( 2823 Context.getCanonicalType(ClassType)); 2824 if (NewFD->getDeclName() != Name) { 2825 Diag(NewFD->getLocation(), diag::err_destructor_name); 2826 return NewFD->setInvalidDecl(); 2827 } 2828 } 2829 Record->setUserDeclaredDestructor(true); 2830 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2831 // user-defined destructor. 2832 Record->setPOD(false); 2833 2834 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2835 // declared destructor. 2836 // FIXME: C++0x: don't do this for "= default" destructors 2837 Record->setHasTrivialDestructor(false); 2838 } else if (CXXConversionDecl *Conversion 2839 = dyn_cast<CXXConversionDecl>(NewFD)) 2840 ActOnConversionDeclarator(Conversion); 2841 2842 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2843 if (NewFD->isOverloadedOperator() && 2844 CheckOverloadedOperatorDeclaration(NewFD)) 2845 return NewFD->setInvalidDecl(); 2846 } 2847 2848 // C99 6.7.4p6: 2849 // [... ] For a function with external linkage, the following 2850 // restrictions apply: [...] If all of the file scope declarations 2851 // for a function in a translation unit include the inline 2852 // function specifier without extern, then the definition in that 2853 // translation unit is an inline definition. An inline definition 2854 // does not provide an external definition for the function, and 2855 // does not forbid an external definition in another translation 2856 // unit. 2857 // 2858 // Here we determine whether this function, in isolation, would be a 2859 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2860 // previous declarations. 2861 if (NewFD->isInline() && getLangOptions().C99 && 2862 NewFD->getStorageClass() == FunctionDecl::None && 2863 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2864 NewFD->setC99InlineDefinition(true); 2865 2866 // Check for a previous declaration of this name. 2867 if (!PrevDecl && NewFD->isExternC(Context)) { 2868 // Since we did not find anything by this name and we're declaring 2869 // an extern "C" function, look for a non-visible extern "C" 2870 // declaration with the same name. 2871 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2872 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2873 if (Pos != LocallyScopedExternalDecls.end()) 2874 PrevDecl = Pos->second; 2875 } 2876 2877 // Merge or overload the declaration with an existing declaration of 2878 // the same name, if appropriate. 2879 if (PrevDecl) { 2880 // Determine whether NewFD is an overload of PrevDecl or 2881 // a declaration that requires merging. If it's an overload, 2882 // there's no more work to do here; we'll just add the new 2883 // function to the scope. 2884 OverloadedFunctionDecl::function_iterator MatchedDecl; 2885 2886 if (!getLangOptions().CPlusPlus && 2887 AllowOverloadingOfFunction(PrevDecl, Context)) { 2888 OverloadableAttrRequired = true; 2889 2890 // Functions marked "overloadable" must have a prototype (that 2891 // we can't get through declaration merging). 2892 if (!NewFD->getType()->getAsFunctionProtoType()) { 2893 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2894 << NewFD; 2895 Redeclaration = true; 2896 2897 // Turn this into a variadic function with no parameters. 2898 QualType R = Context.getFunctionType( 2899 NewFD->getType()->getAsFunctionType()->getResultType(), 2900 0, 0, true, 0); 2901 NewFD->setType(R); 2902 return NewFD->setInvalidDecl(); 2903 } 2904 } 2905 2906 if (PrevDecl && 2907 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2908 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2909 Redeclaration = true; 2910 Decl *OldDecl = PrevDecl; 2911 2912 // If PrevDecl was an overloaded function, extract the 2913 // FunctionDecl that matched. 2914 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2915 OldDecl = *MatchedDecl; 2916 2917 // NewFD and OldDecl represent declarations that need to be 2918 // merged. 2919 if (MergeFunctionDecl(NewFD, OldDecl)) 2920 return NewFD->setInvalidDecl(); 2921 2922 if (FunctionTemplateDecl *OldTemplateDecl 2923 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2924 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2925 else { 2926 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2927 NewFD->setAccess(OldDecl->getAccess()); 2928 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2929 } 2930 } 2931 } 2932 2933 // In C++, check default arguments now that we have merged decls. Unless 2934 // the lexical context is the class, because in this case this is done 2935 // during delayed parsing anyway. 2936 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2937 CheckCXXDefaultArguments(NewFD); 2938} 2939 2940void Sema::CheckMain(FunctionDecl* FD) { 2941 // C++ [basic.start.main]p3: A program that declares main to be inline 2942 // or static is ill-formed. 2943 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2944 // shall not appear in a declaration of main. 2945 // static main is not an error under C99, but we should warn about it. 2946 bool isInline = FD->isInline(); 2947 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2948 if (isInline || isStatic) { 2949 unsigned diagID = diag::warn_unusual_main_decl; 2950 if (isInline || getLangOptions().CPlusPlus) 2951 diagID = diag::err_unusual_main_decl; 2952 2953 int which = isStatic + (isInline << 1) - 1; 2954 Diag(FD->getLocation(), diagID) << which; 2955 } 2956 2957 QualType T = FD->getType(); 2958 assert(T->isFunctionType() && "function decl is not of function type"); 2959 const FunctionType* FT = T->getAsFunctionType(); 2960 2961 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2962 // TODO: add a replacement fixit to turn the return type into 'int'. 2963 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2964 FD->setInvalidDecl(true); 2965 } 2966 2967 // Treat protoless main() as nullary. 2968 if (isa<FunctionNoProtoType>(FT)) return; 2969 2970 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2971 unsigned nparams = FTP->getNumArgs(); 2972 assert(FD->getNumParams() == nparams); 2973 2974 if (nparams > 3) { 2975 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2976 FD->setInvalidDecl(true); 2977 nparams = 3; 2978 } 2979 2980 // FIXME: a lot of the following diagnostics would be improved 2981 // if we had some location information about types. 2982 2983 QualType CharPP = 2984 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2985 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2986 2987 for (unsigned i = 0; i < nparams; ++i) { 2988 QualType AT = FTP->getArgType(i); 2989 2990 bool mismatch = true; 2991 2992 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2993 mismatch = false; 2994 else if (Expected[i] == CharPP) { 2995 // As an extension, the following forms are okay: 2996 // char const ** 2997 // char const * const * 2998 // char * const * 2999 3000 QualifierSet qs; 3001 const PointerType* PT; 3002 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3003 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3004 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3005 qs.removeConst(); 3006 mismatch = !qs.empty(); 3007 } 3008 } 3009 3010 if (mismatch) { 3011 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3012 // TODO: suggest replacing given type with expected type 3013 FD->setInvalidDecl(true); 3014 } 3015 } 3016 3017 if (nparams == 1 && !FD->isInvalidDecl()) { 3018 Diag(FD->getLocation(), diag::warn_main_one_arg); 3019 } 3020} 3021 3022bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3023 // FIXME: Need strict checking. In C89, we need to check for 3024 // any assignment, increment, decrement, function-calls, or 3025 // commas outside of a sizeof. In C99, it's the same list, 3026 // except that the aforementioned are allowed in unevaluated 3027 // expressions. Everything else falls under the 3028 // "may accept other forms of constant expressions" exception. 3029 // (We never end up here for C++, so the constant expression 3030 // rules there don't matter.) 3031 if (Init->isConstantInitializer(Context)) 3032 return false; 3033 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3034 << Init->getSourceRange(); 3035 return true; 3036} 3037 3038void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3039 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3040} 3041 3042/// AddInitializerToDecl - Adds the initializer Init to the 3043/// declaration dcl. If DirectInit is true, this is C++ direct 3044/// initialization rather than copy initialization. 3045void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3046 Decl *RealDecl = dcl.getAs<Decl>(); 3047 // If there is no declaration, there was an error parsing it. Just ignore 3048 // the initializer. 3049 if (RealDecl == 0) 3050 return; 3051 3052 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3053 // With declarators parsed the way they are, the parser cannot 3054 // distinguish between a normal initializer and a pure-specifier. 3055 // Thus this grotesque test. 3056 IntegerLiteral *IL; 3057 Expr *Init = static_cast<Expr *>(init.get()); 3058 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3059 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3060 if (Method->isVirtualAsWritten()) { 3061 Method->setPure(); 3062 3063 // A class is abstract if at least one function is pure virtual. 3064 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3065 } else if (!Method->isInvalidDecl()) { 3066 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3067 << Method->getDeclName() << Init->getSourceRange(); 3068 Method->setInvalidDecl(); 3069 } 3070 } else { 3071 Diag(Method->getLocation(), diag::err_member_function_initialization) 3072 << Method->getDeclName() << Init->getSourceRange(); 3073 Method->setInvalidDecl(); 3074 } 3075 return; 3076 } 3077 3078 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3079 if (!VDecl) { 3080 if (getLangOptions().CPlusPlus && 3081 RealDecl->getLexicalDeclContext()->isRecord() && 3082 isa<NamedDecl>(RealDecl)) 3083 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3084 << cast<NamedDecl>(RealDecl)->getDeclName(); 3085 else 3086 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3087 RealDecl->setInvalidDecl(); 3088 return; 3089 } 3090 3091 if (!VDecl->getType()->isArrayType() && 3092 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3093 diag::err_typecheck_decl_incomplete_type)) { 3094 RealDecl->setInvalidDecl(); 3095 return; 3096 } 3097 3098 const VarDecl *Def = 0; 3099 if (VDecl->getDefinition(Def)) { 3100 Diag(VDecl->getLocation(), diag::err_redefinition) 3101 << VDecl->getDeclName(); 3102 Diag(Def->getLocation(), diag::note_previous_definition); 3103 VDecl->setInvalidDecl(); 3104 return; 3105 } 3106 3107 // Take ownership of the expression, now that we're sure we have somewhere 3108 // to put it. 3109 Expr *Init = init.takeAs<Expr>(); 3110 assert(Init && "missing initializer"); 3111 3112 // Get the decls type and save a reference for later, since 3113 // CheckInitializerTypes may change it. 3114 QualType DclT = VDecl->getType(), SavT = DclT; 3115 if (VDecl->isBlockVarDecl()) { 3116 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3117 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3118 VDecl->setInvalidDecl(); 3119 } else if (!VDecl->isInvalidDecl()) { 3120 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3121 VDecl->getDeclName(), DirectInit)) 3122 VDecl->setInvalidDecl(); 3123 3124 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3125 // Don't check invalid declarations to avoid emitting useless diagnostics. 3126 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3127 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3128 CheckForConstantInitializer(Init, DclT); 3129 } 3130 } 3131 } else if (VDecl->isStaticDataMember() && 3132 VDecl->getLexicalDeclContext()->isRecord()) { 3133 // This is an in-class initialization for a static data member, e.g., 3134 // 3135 // struct S { 3136 // static const int value = 17; 3137 // }; 3138 3139 // Attach the initializer 3140 VDecl->setInit(Context, Init); 3141 3142 // C++ [class.mem]p4: 3143 // A member-declarator can contain a constant-initializer only 3144 // if it declares a static member (9.4) of const integral or 3145 // const enumeration type, see 9.4.2. 3146 QualType T = VDecl->getType(); 3147 if (!T->isDependentType() && 3148 (!Context.getCanonicalType(T).isConstQualified() || 3149 !T->isIntegralType())) { 3150 Diag(VDecl->getLocation(), diag::err_member_initialization) 3151 << VDecl->getDeclName() << Init->getSourceRange(); 3152 VDecl->setInvalidDecl(); 3153 } else { 3154 // C++ [class.static.data]p4: 3155 // If a static data member is of const integral or const 3156 // enumeration type, its declaration in the class definition 3157 // can specify a constant-initializer which shall be an 3158 // integral constant expression (5.19). 3159 if (!Init->isTypeDependent() && 3160 !Init->getType()->isIntegralType()) { 3161 // We have a non-dependent, non-integral or enumeration type. 3162 Diag(Init->getSourceRange().getBegin(), 3163 diag::err_in_class_initializer_non_integral_type) 3164 << Init->getType() << Init->getSourceRange(); 3165 VDecl->setInvalidDecl(); 3166 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3167 // Check whether the expression is a constant expression. 3168 llvm::APSInt Value; 3169 SourceLocation Loc; 3170 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3171 Diag(Loc, diag::err_in_class_initializer_non_constant) 3172 << Init->getSourceRange(); 3173 VDecl->setInvalidDecl(); 3174 } else if (!VDecl->getType()->isDependentType()) 3175 ImpCastExprToType(Init, VDecl->getType()); 3176 } 3177 } 3178 } else if (VDecl->isFileVarDecl()) { 3179 if (VDecl->getStorageClass() == VarDecl::Extern) 3180 Diag(VDecl->getLocation(), diag::warn_extern_init); 3181 if (!VDecl->isInvalidDecl()) 3182 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3183 VDecl->getDeclName(), DirectInit)) 3184 VDecl->setInvalidDecl(); 3185 3186 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3187 // Don't check invalid declarations to avoid emitting useless diagnostics. 3188 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3189 // C99 6.7.8p4. All file scoped initializers need to be constant. 3190 CheckForConstantInitializer(Init, DclT); 3191 } 3192 } 3193 // If the type changed, it means we had an incomplete type that was 3194 // completed by the initializer. For example: 3195 // int ary[] = { 1, 3, 5 }; 3196 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3197 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3198 VDecl->setType(DclT); 3199 Init->setType(DclT); 3200 } 3201 3202 Init = MaybeCreateCXXExprWithTemporaries(Init, 3203 /*ShouldDestroyTemporaries=*/true); 3204 // Attach the initializer to the decl. 3205 VDecl->setInit(Context, Init); 3206 3207 // If the previous declaration of VDecl was a tentative definition, 3208 // remove it from the set of tentative definitions. 3209 if (VDecl->getPreviousDeclaration() && 3210 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3211 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 3212 = TentativeDefinitions.find(VDecl->getDeclName()); 3213 assert(Pos != TentativeDefinitions.end() && 3214 "Unrecorded tentative definition?"); 3215 TentativeDefinitions.erase(Pos); 3216 } 3217 3218 return; 3219} 3220 3221void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3222 bool TypeContainsUndeducedAuto) { 3223 Decl *RealDecl = dcl.getAs<Decl>(); 3224 3225 // If there is no declaration, there was an error parsing it. Just ignore it. 3226 if (RealDecl == 0) 3227 return; 3228 3229 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3230 QualType Type = Var->getType(); 3231 3232 // Record tentative definitions. 3233 if (Var->isTentativeDefinition(Context)) 3234 TentativeDefinitions[Var->getDeclName()] = Var; 3235 3236 // C++ [dcl.init.ref]p3: 3237 // The initializer can be omitted for a reference only in a 3238 // parameter declaration (8.3.5), in the declaration of a 3239 // function return type, in the declaration of a class member 3240 // within its class declaration (9.2), and where the extern 3241 // specifier is explicitly used. 3242 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3243 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3244 << Var->getDeclName() 3245 << SourceRange(Var->getLocation(), Var->getLocation()); 3246 Var->setInvalidDecl(); 3247 return; 3248 } 3249 3250 // C++0x [dcl.spec.auto]p3 3251 if (TypeContainsUndeducedAuto) { 3252 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3253 << Var->getDeclName() << Type; 3254 Var->setInvalidDecl(); 3255 return; 3256 } 3257 3258 // C++ [dcl.init]p9: 3259 // 3260 // If no initializer is specified for an object, and the object 3261 // is of (possibly cv-qualified) non-POD class type (or array 3262 // thereof), the object shall be default-initialized; if the 3263 // object is of const-qualified type, the underlying class type 3264 // shall have a user-declared default constructor. 3265 if (getLangOptions().CPlusPlus) { 3266 QualType InitType = Type; 3267 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3268 InitType = Array->getElementType(); 3269 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 3270 InitType->isRecordType() && !InitType->isDependentType()) { 3271 CXXRecordDecl *RD = 3272 cast<CXXRecordDecl>(InitType->getAs<RecordType>()->getDecl()); 3273 CXXConstructorDecl *Constructor = 0; 3274 if (!RequireCompleteType(Var->getLocation(), InitType, 3275 diag::err_invalid_incomplete_type_use)) 3276 Constructor 3277 = PerformInitializationByConstructor(InitType, 0, 0, 3278 Var->getLocation(), 3279 SourceRange(Var->getLocation(), 3280 Var->getLocation()), 3281 Var->getDeclName(), 3282 IK_Default); 3283 if (!Constructor) 3284 Var->setInvalidDecl(); 3285 else { 3286 if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()) { 3287 if (InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0)) 3288 Var->setInvalidDecl(); 3289 } 3290 3291 FinalizeVarWithDestructor(Var, InitType); 3292 } 3293 } 3294 } 3295 3296#if 0 3297 // FIXME: Temporarily disabled because we are not properly parsing 3298 // linkage specifications on declarations, e.g., 3299 // 3300 // extern "C" const CGPoint CGPointerZero; 3301 // 3302 // C++ [dcl.init]p9: 3303 // 3304 // If no initializer is specified for an object, and the 3305 // object is of (possibly cv-qualified) non-POD class type (or 3306 // array thereof), the object shall be default-initialized; if 3307 // the object is of const-qualified type, the underlying class 3308 // type shall have a user-declared default 3309 // constructor. Otherwise, if no initializer is specified for 3310 // an object, the object and its subobjects, if any, have an 3311 // indeterminate initial value; if the object or any of its 3312 // subobjects are of const-qualified type, the program is 3313 // ill-formed. 3314 // 3315 // This isn't technically an error in C, so we don't diagnose it. 3316 // 3317 // FIXME: Actually perform the POD/user-defined default 3318 // constructor check. 3319 if (getLangOptions().CPlusPlus && 3320 Context.getCanonicalType(Type).isConstQualified() && 3321 !Var->hasExternalStorage()) 3322 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3323 << Var->getName() 3324 << SourceRange(Var->getLocation(), Var->getLocation()); 3325#endif 3326 } 3327} 3328 3329Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3330 DeclPtrTy *Group, 3331 unsigned NumDecls) { 3332 llvm::SmallVector<Decl*, 8> Decls; 3333 3334 if (DS.isTypeSpecOwned()) 3335 Decls.push_back((Decl*)DS.getTypeRep()); 3336 3337 for (unsigned i = 0; i != NumDecls; ++i) 3338 if (Decl *D = Group[i].getAs<Decl>()) 3339 Decls.push_back(D); 3340 3341 // Perform semantic analysis that depends on having fully processed both 3342 // the declarator and initializer. 3343 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3344 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3345 if (!IDecl) 3346 continue; 3347 QualType T = IDecl->getType(); 3348 3349 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3350 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3351 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3352 if (!IDecl->isInvalidDecl() && 3353 RequireCompleteType(IDecl->getLocation(), T, 3354 diag::err_typecheck_decl_incomplete_type)) 3355 IDecl->setInvalidDecl(); 3356 } 3357 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3358 // object that has file scope without an initializer, and without a 3359 // storage-class specifier or with the storage-class specifier "static", 3360 // constitutes a tentative definition. Note: A tentative definition with 3361 // external linkage is valid (C99 6.2.2p5). 3362 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3363 if (const IncompleteArrayType *ArrayT 3364 = Context.getAsIncompleteArrayType(T)) { 3365 if (RequireCompleteType(IDecl->getLocation(), 3366 ArrayT->getElementType(), 3367 diag::err_illegal_decl_array_incomplete_type)) 3368 IDecl->setInvalidDecl(); 3369 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3370 // C99 6.9.2p3: If the declaration of an identifier for an object is 3371 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3372 // declared type shall not be an incomplete type. 3373 // NOTE: code such as the following 3374 // static struct s; 3375 // struct s { int a; }; 3376 // is accepted by gcc. Hence here we issue a warning instead of 3377 // an error and we do not invalidate the static declaration. 3378 // NOTE: to avoid multiple warnings, only check the first declaration. 3379 if (IDecl->getPreviousDeclaration() == 0) 3380 RequireCompleteType(IDecl->getLocation(), T, 3381 diag::ext_typecheck_decl_incomplete_type); 3382 } 3383 } 3384 } 3385 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3386 Decls.data(), Decls.size())); 3387} 3388 3389 3390/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3391/// to introduce parameters into function prototype scope. 3392Sema::DeclPtrTy 3393Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3394 const DeclSpec &DS = D.getDeclSpec(); 3395 3396 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3397 VarDecl::StorageClass StorageClass = VarDecl::None; 3398 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3399 StorageClass = VarDecl::Register; 3400 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3401 Diag(DS.getStorageClassSpecLoc(), 3402 diag::err_invalid_storage_class_in_func_decl); 3403 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3404 } 3405 3406 if (D.getDeclSpec().isThreadSpecified()) 3407 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3408 3409 DiagnoseFunctionSpecifiers(D); 3410 3411 // Check that there are no default arguments inside the type of this 3412 // parameter (C++ only). 3413 if (getLangOptions().CPlusPlus) 3414 CheckExtraCXXDefaultArguments(D); 3415 3416 DeclaratorInfo *DInfo = 0; 3417 TagDecl *OwnedDecl = 0; 3418 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3419 &OwnedDecl); 3420 3421 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3422 // C++ [dcl.fct]p6: 3423 // Types shall not be defined in return or parameter types. 3424 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3425 << Context.getTypeDeclType(OwnedDecl); 3426 } 3427 3428 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3429 // Can this happen for params? We already checked that they don't conflict 3430 // among each other. Here they can only shadow globals, which is ok. 3431 IdentifierInfo *II = D.getIdentifier(); 3432 if (II) { 3433 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3434 if (PrevDecl->isTemplateParameter()) { 3435 // Maybe we will complain about the shadowed template parameter. 3436 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3437 // Just pretend that we didn't see the previous declaration. 3438 PrevDecl = 0; 3439 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3440 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3441 3442 // Recover by removing the name 3443 II = 0; 3444 D.SetIdentifier(0, D.getIdentifierLoc()); 3445 } 3446 } 3447 } 3448 3449 // Parameters can not be abstract class types. 3450 // For record types, this is done by the AbstractClassUsageDiagnoser once 3451 // the class has been completely parsed. 3452 if (!CurContext->isRecord() && 3453 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3454 diag::err_abstract_type_in_decl, 3455 AbstractParamType)) 3456 D.setInvalidType(true); 3457 3458 QualType T = adjustParameterType(parmDeclType); 3459 3460 ParmVarDecl *New; 3461 if (T == parmDeclType) // parameter type did not need adjustment 3462 New = ParmVarDecl::Create(Context, CurContext, 3463 D.getIdentifierLoc(), II, 3464 parmDeclType, DInfo, StorageClass, 3465 0); 3466 else // keep track of both the adjusted and unadjusted types 3467 New = OriginalParmVarDecl::Create(Context, CurContext, 3468 D.getIdentifierLoc(), II, T, DInfo, 3469 parmDeclType, StorageClass, 0); 3470 3471 if (D.isInvalidType()) 3472 New->setInvalidDecl(); 3473 3474 // Parameter declarators cannot be interface types. All ObjC objects are 3475 // passed by reference. 3476 if (T->isObjCInterfaceType()) { 3477 Diag(D.getIdentifierLoc(), 3478 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3479 New->setInvalidDecl(); 3480 } 3481 3482 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3483 if (D.getCXXScopeSpec().isSet()) { 3484 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3485 << D.getCXXScopeSpec().getRange(); 3486 New->setInvalidDecl(); 3487 } 3488 3489 // Add the parameter declaration into this scope. 3490 S->AddDecl(DeclPtrTy::make(New)); 3491 if (II) 3492 IdResolver.AddDecl(New); 3493 3494 ProcessDeclAttributes(S, New, D); 3495 3496 if (New->hasAttr<BlocksAttr>()) { 3497 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3498 } 3499 return DeclPtrTy::make(New); 3500} 3501 3502void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3503 SourceLocation LocAfterDecls) { 3504 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3505 "Not a function declarator!"); 3506 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3507 3508 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3509 // for a K&R function. 3510 if (!FTI.hasPrototype) { 3511 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3512 --i; 3513 if (FTI.ArgInfo[i].Param == 0) { 3514 std::string Code = " int "; 3515 Code += FTI.ArgInfo[i].Ident->getName(); 3516 Code += ";\n"; 3517 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3518 << FTI.ArgInfo[i].Ident 3519 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3520 3521 // Implicitly declare the argument as type 'int' for lack of a better 3522 // type. 3523 DeclSpec DS; 3524 const char* PrevSpec; // unused 3525 unsigned DiagID; // unused 3526 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3527 PrevSpec, DiagID); 3528 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3529 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3530 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3531 } 3532 } 3533 } 3534} 3535 3536Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3537 Declarator &D) { 3538 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3539 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3540 "Not a function declarator!"); 3541 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3542 3543 if (FTI.hasPrototype) { 3544 // FIXME: Diagnose arguments without names in C. 3545 } 3546 3547 Scope *ParentScope = FnBodyScope->getParent(); 3548 3549 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3550 MultiTemplateParamsArg(*this), 3551 /*IsFunctionDefinition=*/true); 3552 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3553} 3554 3555Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3556 if (!D) 3557 return D; 3558 FunctionDecl *FD = 0; 3559 3560 if (FunctionTemplateDecl *FunTmpl 3561 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3562 FD = FunTmpl->getTemplatedDecl(); 3563 else 3564 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3565 3566 CurFunctionNeedsScopeChecking = false; 3567 3568 // See if this is a redefinition. 3569 const FunctionDecl *Definition; 3570 if (FD->getBody(Definition)) { 3571 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3572 Diag(Definition->getLocation(), diag::note_previous_definition); 3573 } 3574 3575 // Builtin functions cannot be defined. 3576 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3577 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3578 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3579 FD->setInvalidDecl(); 3580 } 3581 } 3582 3583 // The return type of a function definition must be complete 3584 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3585 QualType ResultType = FD->getResultType(); 3586 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3587 !FD->isInvalidDecl() && 3588 RequireCompleteType(FD->getLocation(), ResultType, 3589 diag::err_func_def_incomplete_result)) 3590 FD->setInvalidDecl(); 3591 3592 // GNU warning -Wmissing-prototypes: 3593 // Warn if a global function is defined without a previous 3594 // prototype declaration. This warning is issued even if the 3595 // definition itself provides a prototype. The aim is to detect 3596 // global functions that fail to be declared in header files. 3597 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3598 !FD->isMain(Context)) { 3599 bool MissingPrototype = true; 3600 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3601 Prev; Prev = Prev->getPreviousDeclaration()) { 3602 // Ignore any declarations that occur in function or method 3603 // scope, because they aren't visible from the header. 3604 if (Prev->getDeclContext()->isFunctionOrMethod()) 3605 continue; 3606 3607 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3608 break; 3609 } 3610 3611 if (MissingPrototype) 3612 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3613 } 3614 3615 if (FnBodyScope) 3616 PushDeclContext(FnBodyScope, FD); 3617 3618 // Check the validity of our function parameters 3619 CheckParmsForFunctionDef(FD); 3620 3621 // Introduce our parameters into the function scope 3622 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3623 ParmVarDecl *Param = FD->getParamDecl(p); 3624 Param->setOwningFunction(FD); 3625 3626 // If this has an identifier, add it to the scope stack. 3627 if (Param->getIdentifier() && FnBodyScope) 3628 PushOnScopeChains(Param, FnBodyScope); 3629 } 3630 3631 // Checking attributes of current function definition 3632 // dllimport attribute. 3633 if (FD->getAttr<DLLImportAttr>() && 3634 (!FD->getAttr<DLLExportAttr>())) { 3635 // dllimport attribute cannot be applied to definition. 3636 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3637 Diag(FD->getLocation(), 3638 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3639 << "dllimport"; 3640 FD->setInvalidDecl(); 3641 return DeclPtrTy::make(FD); 3642 } else { 3643 // If a symbol previously declared dllimport is later defined, the 3644 // attribute is ignored in subsequent references, and a warning is 3645 // emitted. 3646 Diag(FD->getLocation(), 3647 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3648 << FD->getNameAsCString() << "dllimport"; 3649 } 3650 } 3651 return DeclPtrTy::make(FD); 3652} 3653 3654Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3655 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3656} 3657 3658Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3659 bool IsInstantiation) { 3660 Decl *dcl = D.getAs<Decl>(); 3661 Stmt *Body = BodyArg.takeAs<Stmt>(); 3662 3663 FunctionDecl *FD = 0; 3664 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3665 if (FunTmpl) 3666 FD = FunTmpl->getTemplatedDecl(); 3667 else 3668 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3669 3670 if (FD) { 3671 FD->setBody(Body); 3672 if (FD->isMain(Context)) 3673 // C and C++ allow for main to automagically return 0. 3674 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3675 FD->setHasImplicitReturnZero(true); 3676 else 3677 CheckFallThroughForFunctionDef(FD, Body); 3678 3679 if (!FD->isInvalidDecl()) 3680 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3681 3682 // C++ [basic.def.odr]p2: 3683 // [...] A virtual member function is used if it is not pure. [...] 3684 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3685 if (Method->isVirtual() && !Method->isPure()) 3686 MarkDeclarationReferenced(Method->getLocation(), Method); 3687 3688 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3689 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3690 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3691 MD->setBody(Body); 3692 CheckFallThroughForFunctionDef(MD, Body); 3693 MD->setEndLoc(Body->getLocEnd()); 3694 3695 if (!MD->isInvalidDecl()) 3696 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3697 } else { 3698 Body->Destroy(Context); 3699 return DeclPtrTy(); 3700 } 3701 if (!IsInstantiation) 3702 PopDeclContext(); 3703 3704 // Verify and clean out per-function state. 3705 3706 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3707 3708 // Check goto/label use. 3709 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3710 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3711 LabelStmt *L = I->second; 3712 3713 // Verify that we have no forward references left. If so, there was a goto 3714 // or address of a label taken, but no definition of it. Label fwd 3715 // definitions are indicated with a null substmt. 3716 if (L->getSubStmt() != 0) 3717 continue; 3718 3719 // Emit error. 3720 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3721 3722 // At this point, we have gotos that use the bogus label. Stitch it into 3723 // the function body so that they aren't leaked and that the AST is well 3724 // formed. 3725 if (Body == 0) { 3726 // The whole function wasn't parsed correctly, just delete this. 3727 L->Destroy(Context); 3728 continue; 3729 } 3730 3731 // Otherwise, the body is valid: we want to stitch the label decl into the 3732 // function somewhere so that it is properly owned and so that the goto 3733 // has a valid target. Do this by creating a new compound stmt with the 3734 // label in it. 3735 3736 // Give the label a sub-statement. 3737 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3738 3739 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3740 cast<CXXTryStmt>(Body)->getTryBlock() : 3741 cast<CompoundStmt>(Body); 3742 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3743 Elements.push_back(L); 3744 Compound->setStmts(Context, &Elements[0], Elements.size()); 3745 } 3746 FunctionLabelMap.clear(); 3747 3748 if (!Body) return D; 3749 3750 // Verify that that gotos and switch cases don't jump into scopes illegally. 3751 if (CurFunctionNeedsScopeChecking) 3752 DiagnoseInvalidJumps(Body); 3753 3754 // C++ constructors that have function-try-blocks can't have return 3755 // statements in the handlers of that block. (C++ [except.handle]p14) 3756 // Verify this. 3757 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3758 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3759 3760 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3761 Destructor->computeBaseOrMembersToDestroy(Context); 3762 return D; 3763} 3764 3765/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3766/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3767NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3768 IdentifierInfo &II, Scope *S) { 3769 // Before we produce a declaration for an implicitly defined 3770 // function, see whether there was a locally-scoped declaration of 3771 // this name as a function or variable. If so, use that 3772 // (non-visible) declaration, and complain about it. 3773 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3774 = LocallyScopedExternalDecls.find(&II); 3775 if (Pos != LocallyScopedExternalDecls.end()) { 3776 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3777 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3778 return Pos->second; 3779 } 3780 3781 // Extension in C99. Legal in C90, but warn about it. 3782 if (getLangOptions().C99) 3783 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3784 else 3785 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3786 3787 // FIXME: handle stuff like: 3788 // void foo() { extern float X(); } 3789 // void bar() { X(); } <-- implicit decl for X in another scope. 3790 3791 // Set a Declarator for the implicit definition: int foo(); 3792 const char *Dummy; 3793 DeclSpec DS; 3794 unsigned DiagID; 3795 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3796 Error = Error; // Silence warning. 3797 assert(!Error && "Error setting up implicit decl!"); 3798 Declarator D(DS, Declarator::BlockContext); 3799 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3800 0, 0, false, SourceLocation(), 3801 false, 0,0,0, Loc, Loc, D), 3802 SourceLocation()); 3803 D.SetIdentifier(&II, Loc); 3804 3805 // Insert this function into translation-unit scope. 3806 3807 DeclContext *PrevDC = CurContext; 3808 CurContext = Context.getTranslationUnitDecl(); 3809 3810 FunctionDecl *FD = 3811 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3812 FD->setImplicit(); 3813 3814 CurContext = PrevDC; 3815 3816 AddKnownFunctionAttributes(FD); 3817 3818 return FD; 3819} 3820 3821/// \brief Adds any function attributes that we know a priori based on 3822/// the declaration of this function. 3823/// 3824/// These attributes can apply both to implicitly-declared builtins 3825/// (like __builtin___printf_chk) or to library-declared functions 3826/// like NSLog or printf. 3827void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3828 if (FD->isInvalidDecl()) 3829 return; 3830 3831 // If this is a built-in function, map its builtin attributes to 3832 // actual attributes. 3833 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3834 // Handle printf-formatting attributes. 3835 unsigned FormatIdx; 3836 bool HasVAListArg; 3837 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3838 if (!FD->getAttr<FormatAttr>()) 3839 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3840 HasVAListArg ? 0 : FormatIdx + 2)); 3841 } 3842 3843 // Mark const if we don't care about errno and that is the only 3844 // thing preventing the function from being const. This allows 3845 // IRgen to use LLVM intrinsics for such functions. 3846 if (!getLangOptions().MathErrno && 3847 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3848 if (!FD->getAttr<ConstAttr>()) 3849 FD->addAttr(::new (Context) ConstAttr()); 3850 } 3851 3852 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3853 FD->addAttr(::new (Context) NoReturnAttr()); 3854 } 3855 3856 IdentifierInfo *Name = FD->getIdentifier(); 3857 if (!Name) 3858 return; 3859 if ((!getLangOptions().CPlusPlus && 3860 FD->getDeclContext()->isTranslationUnit()) || 3861 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3862 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3863 LinkageSpecDecl::lang_c)) { 3864 // Okay: this could be a libc/libm/Objective-C function we know 3865 // about. 3866 } else 3867 return; 3868 3869 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3870 // FIXME: NSLog and NSLogv should be target specific 3871 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3872 // FIXME: We known better than our headers. 3873 const_cast<FormatAttr *>(Format)->setType("printf"); 3874 } else 3875 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3876 Name->isStr("NSLogv") ? 0 : 2)); 3877 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3878 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3879 // target-specific builtins, perhaps? 3880 if (!FD->getAttr<FormatAttr>()) 3881 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3882 Name->isStr("vasprintf") ? 0 : 3)); 3883 } 3884} 3885 3886TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3887 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3888 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3889 3890 // Scope manipulation handled by caller. 3891 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3892 D.getIdentifierLoc(), 3893 D.getIdentifier(), 3894 T); 3895 3896 if (TagType *TT = dyn_cast<TagType>(T)) { 3897 TagDecl *TD = TT->getDecl(); 3898 3899 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3900 // keep track of the TypedefDecl. 3901 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3902 TD->setTypedefForAnonDecl(NewTD); 3903 } 3904 3905 if (D.isInvalidType()) 3906 NewTD->setInvalidDecl(); 3907 return NewTD; 3908} 3909 3910 3911/// \brief Determine whether a tag with a given kind is acceptable 3912/// as a redeclaration of the given tag declaration. 3913/// 3914/// \returns true if the new tag kind is acceptable, false otherwise. 3915bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3916 TagDecl::TagKind NewTag, 3917 SourceLocation NewTagLoc, 3918 const IdentifierInfo &Name) { 3919 // C++ [dcl.type.elab]p3: 3920 // The class-key or enum keyword present in the 3921 // elaborated-type-specifier shall agree in kind with the 3922 // declaration to which the name in theelaborated-type-specifier 3923 // refers. This rule also applies to the form of 3924 // elaborated-type-specifier that declares a class-name or 3925 // friend class since it can be construed as referring to the 3926 // definition of the class. Thus, in any 3927 // elaborated-type-specifier, the enum keyword shall be used to 3928 // refer to an enumeration (7.2), the union class-keyshall be 3929 // used to refer to a union (clause 9), and either the class or 3930 // struct class-key shall be used to refer to a class (clause 9) 3931 // declared using the class or struct class-key. 3932 TagDecl::TagKind OldTag = Previous->getTagKind(); 3933 if (OldTag == NewTag) 3934 return true; 3935 3936 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3937 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3938 // Warn about the struct/class tag mismatch. 3939 bool isTemplate = false; 3940 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3941 isTemplate = Record->getDescribedClassTemplate(); 3942 3943 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3944 << (NewTag == TagDecl::TK_class) 3945 << isTemplate << &Name 3946 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3947 OldTag == TagDecl::TK_class? "class" : "struct"); 3948 Diag(Previous->getLocation(), diag::note_previous_use); 3949 return true; 3950 } 3951 return false; 3952} 3953 3954/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3955/// former case, Name will be non-null. In the later case, Name will be null. 3956/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3957/// reference/declaration/definition of a tag. 3958Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3959 SourceLocation KWLoc, const CXXScopeSpec &SS, 3960 IdentifierInfo *Name, SourceLocation NameLoc, 3961 AttributeList *Attr, AccessSpecifier AS, 3962 MultiTemplateParamsArg TemplateParameterLists, 3963 bool &OwnedDecl) { 3964 // If this is not a definition, it must have a name. 3965 assert((Name != 0 || TUK == TUK_Definition) && 3966 "Nameless record must be a definition!"); 3967 3968 OwnedDecl = false; 3969 TagDecl::TagKind Kind; 3970 switch (TagSpec) { 3971 default: assert(0 && "Unknown tag type!"); 3972 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3973 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3974 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3975 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3976 } 3977 3978 if (TUK != TUK_Reference) { 3979 if (TemplateParameterList *TemplateParams 3980 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3981 (TemplateParameterList**)TemplateParameterLists.get(), 3982 TemplateParameterLists.size())) { 3983 if (TemplateParams->size() > 0) { 3984 // This is a declaration or definition of a class template (which may 3985 // be a member of another template). 3986 OwnedDecl = false; 3987 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 3988 SS, Name, NameLoc, Attr, 3989 TemplateParams, 3990 AS); 3991 TemplateParameterLists.release(); 3992 return Result.get(); 3993 } else { 3994 // FIXME: diagnose the extraneous 'template<>', once we recover 3995 // slightly better in ParseTemplate.cpp from bogus template 3996 // parameters. 3997 } 3998 } 3999 } 4000 4001 DeclContext *SearchDC = CurContext; 4002 DeclContext *DC = CurContext; 4003 NamedDecl *PrevDecl = 0; 4004 4005 bool Invalid = false; 4006 4007 if (Name && SS.isNotEmpty()) { 4008 // We have a nested-name tag ('struct foo::bar'). 4009 4010 // Check for invalid 'foo::'. 4011 if (SS.isInvalid()) { 4012 Name = 0; 4013 goto CreateNewDecl; 4014 } 4015 4016 if (RequireCompleteDeclContext(SS)) 4017 return DeclPtrTy::make((Decl *)0); 4018 4019 DC = computeDeclContext(SS, true); 4020 SearchDC = DC; 4021 // Look-up name inside 'foo::'. 4022 PrevDecl 4023 = dyn_cast_or_null<TagDecl>( 4024 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4025 4026 // A tag 'foo::bar' must already exist. 4027 if (PrevDecl == 0) { 4028 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4029 Name = 0; 4030 Invalid = true; 4031 goto CreateNewDecl; 4032 } 4033 } else if (Name) { 4034 // If this is a named struct, check to see if there was a previous forward 4035 // declaration or definition. 4036 // FIXME: We're looking into outer scopes here, even when we 4037 // shouldn't be. Doing so can result in ambiguities that we 4038 // shouldn't be diagnosing. 4039 LookupResult R = LookupName(S, Name, LookupTagName, 4040 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4041 if (R.isAmbiguous()) { 4042 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4043 // FIXME: This is not best way to recover from case like: 4044 // 4045 // struct S s; 4046 // 4047 // causes needless "incomplete type" error later. 4048 Name = 0; 4049 PrevDecl = 0; 4050 Invalid = true; 4051 } else 4052 PrevDecl = R; 4053 4054 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4055 // FIXME: This makes sure that we ignore the contexts associated 4056 // with C structs, unions, and enums when looking for a matching 4057 // tag declaration or definition. See the similar lookup tweak 4058 // in Sema::LookupName; is there a better way to deal with this? 4059 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4060 SearchDC = SearchDC->getParent(); 4061 } 4062 } 4063 4064 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4065 // Maybe we will complain about the shadowed template parameter. 4066 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4067 // Just pretend that we didn't see the previous declaration. 4068 PrevDecl = 0; 4069 } 4070 4071 if (PrevDecl) { 4072 // Check whether the previous declaration is usable. 4073 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4074 4075 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4076 // If this is a use of a previous tag, or if the tag is already declared 4077 // in the same scope (so that the definition/declaration completes or 4078 // rementions the tag), reuse the decl. 4079 if (TUK == TUK_Reference || TUK == TUK_Friend || 4080 isDeclInScope(PrevDecl, SearchDC, S)) { 4081 // Make sure that this wasn't declared as an enum and now used as a 4082 // struct or something similar. 4083 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4084 bool SafeToContinue 4085 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4086 Kind != TagDecl::TK_enum); 4087 if (SafeToContinue) 4088 Diag(KWLoc, diag::err_use_with_wrong_tag) 4089 << Name 4090 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4091 PrevTagDecl->getKindName()); 4092 else 4093 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4094 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4095 4096 if (SafeToContinue) 4097 Kind = PrevTagDecl->getTagKind(); 4098 else { 4099 // Recover by making this an anonymous redefinition. 4100 Name = 0; 4101 PrevDecl = 0; 4102 Invalid = true; 4103 } 4104 } 4105 4106 if (!Invalid) { 4107 // If this is a use, just return the declaration we found. 4108 4109 // FIXME: In the future, return a variant or some other clue 4110 // for the consumer of this Decl to know it doesn't own it. 4111 // For our current ASTs this shouldn't be a problem, but will 4112 // need to be changed with DeclGroups. 4113 if (TUK == TUK_Reference) 4114 return DeclPtrTy::make(PrevDecl); 4115 4116 // If this is a friend, make sure we create the new 4117 // declaration in the appropriate semantic context. 4118 if (TUK == TUK_Friend) 4119 SearchDC = PrevDecl->getDeclContext(); 4120 4121 // Diagnose attempts to redefine a tag. 4122 if (TUK == TUK_Definition) { 4123 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4124 Diag(NameLoc, diag::err_redefinition) << Name; 4125 Diag(Def->getLocation(), diag::note_previous_definition); 4126 // If this is a redefinition, recover by making this 4127 // struct be anonymous, which will make any later 4128 // references get the previous definition. 4129 Name = 0; 4130 PrevDecl = 0; 4131 Invalid = true; 4132 } else { 4133 // If the type is currently being defined, complain 4134 // about a nested redefinition. 4135 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4136 if (Tag->isBeingDefined()) { 4137 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4138 Diag(PrevTagDecl->getLocation(), 4139 diag::note_previous_definition); 4140 Name = 0; 4141 PrevDecl = 0; 4142 Invalid = true; 4143 } 4144 } 4145 4146 // Okay, this is definition of a previously declared or referenced 4147 // tag PrevDecl. We're going to create a new Decl for it. 4148 } 4149 } 4150 // If we get here we have (another) forward declaration or we 4151 // have a definition. Just create a new decl. 4152 4153 } else { 4154 // If we get here, this is a definition of a new tag type in a nested 4155 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4156 // new decl/type. We set PrevDecl to NULL so that the entities 4157 // have distinct types. 4158 PrevDecl = 0; 4159 } 4160 // If we get here, we're going to create a new Decl. If PrevDecl 4161 // is non-NULL, it's a definition of the tag declared by 4162 // PrevDecl. If it's NULL, we have a new definition. 4163 } else { 4164 // PrevDecl is a namespace, template, or anything else 4165 // that lives in the IDNS_Tag identifier namespace. 4166 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4167 // The tag name clashes with a namespace name, issue an error and 4168 // recover by making this tag be anonymous. 4169 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4170 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4171 Name = 0; 4172 PrevDecl = 0; 4173 Invalid = true; 4174 } else { 4175 // The existing declaration isn't relevant to us; we're in a 4176 // new scope, so clear out the previous declaration. 4177 PrevDecl = 0; 4178 } 4179 } 4180 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4181 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4182 // C++ [basic.scope.pdecl]p5: 4183 // -- for an elaborated-type-specifier of the form 4184 // 4185 // class-key identifier 4186 // 4187 // if the elaborated-type-specifier is used in the 4188 // decl-specifier-seq or parameter-declaration-clause of a 4189 // function defined in namespace scope, the identifier is 4190 // declared as a class-name in the namespace that contains 4191 // the declaration; otherwise, except as a friend 4192 // declaration, the identifier is declared in the smallest 4193 // non-class, non-function-prototype scope that contains the 4194 // declaration. 4195 // 4196 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4197 // C structs and unions. 4198 // 4199 // GNU C also supports this behavior as part of its incomplete 4200 // enum types extension, while GNU C++ does not. 4201 // 4202 // Find the context where we'll be declaring the tag. 4203 // FIXME: We would like to maintain the current DeclContext as the 4204 // lexical context, 4205 while (SearchDC->isRecord()) 4206 SearchDC = SearchDC->getParent(); 4207 4208 // Find the scope where we'll be declaring the tag. 4209 while (S->isClassScope() || 4210 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4211 ((S->getFlags() & Scope::DeclScope) == 0) || 4212 (S->getEntity() && 4213 ((DeclContext *)S->getEntity())->isTransparentContext())) 4214 S = S->getParent(); 4215 4216 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4217 // C++ [namespace.memdef]p3: 4218 // If a friend declaration in a non-local class first declares a 4219 // class or function, the friend class or function is a member of 4220 // the innermost enclosing namespace. 4221 while (!SearchDC->isFileContext()) 4222 SearchDC = SearchDC->getParent(); 4223 4224 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4225 while (S->getEntity() != SearchDC) 4226 S = S->getParent(); 4227 } 4228 4229CreateNewDecl: 4230 4231 // If there is an identifier, use the location of the identifier as the 4232 // location of the decl, otherwise use the location of the struct/union 4233 // keyword. 4234 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4235 4236 // Otherwise, create a new declaration. If there is a previous 4237 // declaration of the same entity, the two will be linked via 4238 // PrevDecl. 4239 TagDecl *New; 4240 4241 if (Kind == TagDecl::TK_enum) { 4242 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4243 // enum X { A, B, C } D; D should chain to X. 4244 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4245 cast_or_null<EnumDecl>(PrevDecl)); 4246 // If this is an undefined enum, warn. 4247 if (TUK != TUK_Definition && !Invalid) { 4248 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4249 : diag::ext_forward_ref_enum; 4250 Diag(Loc, DK); 4251 } 4252 } else { 4253 // struct/union/class 4254 4255 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4256 // struct X { int A; } D; D should chain to X. 4257 if (getLangOptions().CPlusPlus) 4258 // FIXME: Look for a way to use RecordDecl for simple structs. 4259 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4260 cast_or_null<CXXRecordDecl>(PrevDecl)); 4261 else 4262 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4263 cast_or_null<RecordDecl>(PrevDecl)); 4264 } 4265 4266 if (Kind != TagDecl::TK_enum) { 4267 // Handle #pragma pack: if the #pragma pack stack has non-default 4268 // alignment, make up a packed attribute for this decl. These 4269 // attributes are checked when the ASTContext lays out the 4270 // structure. 4271 // 4272 // It is important for implementing the correct semantics that this 4273 // happen here (in act on tag decl). The #pragma pack stack is 4274 // maintained as a result of parser callbacks which can occur at 4275 // many points during the parsing of a struct declaration (because 4276 // the #pragma tokens are effectively skipped over during the 4277 // parsing of the struct). 4278 if (unsigned Alignment = getPragmaPackAlignment()) 4279 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4280 } 4281 4282 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4283 // C++ [dcl.typedef]p3: 4284 // [...] Similarly, in a given scope, a class or enumeration 4285 // shall not be declared with the same name as a typedef-name 4286 // that is declared in that scope and refers to a type other 4287 // than the class or enumeration itself. 4288 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4289 TypedefDecl *PrevTypedef = 0; 4290 if (Lookup.getKind() == LookupResult::Found) 4291 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4292 4293 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4294 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4295 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4296 Diag(Loc, diag::err_tag_definition_of_typedef) 4297 << Context.getTypeDeclType(New) 4298 << PrevTypedef->getUnderlyingType(); 4299 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4300 Invalid = true; 4301 } 4302 } 4303 4304 if (Invalid) 4305 New->setInvalidDecl(); 4306 4307 if (Attr) 4308 ProcessDeclAttributeList(S, New, Attr); 4309 4310 // If we're declaring or defining a tag in function prototype scope 4311 // in C, note that this type can only be used within the function. 4312 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4313 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4314 4315 // Set the lexical context. If the tag has a C++ scope specifier, the 4316 // lexical context will be different from the semantic context. 4317 New->setLexicalDeclContext(CurContext); 4318 4319 // Mark this as a friend decl if applicable. 4320 if (TUK == TUK_Friend) 4321 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4322 4323 // Set the access specifier. 4324 if (!Invalid && TUK != TUK_Friend) 4325 SetMemberAccessSpecifier(New, PrevDecl, AS); 4326 4327 if (TUK == TUK_Definition) 4328 New->startDefinition(); 4329 4330 // If this has an identifier, add it to the scope stack. 4331 if (TUK == TUK_Friend) { 4332 // Friend tag decls are visible in fairly strange ways. 4333 if (!CurContext->isDependentContext()) { 4334 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4335 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4336 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4337 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4338 } 4339 } else if (Name) { 4340 S = getNonFieldDeclScope(S); 4341 PushOnScopeChains(New, S); 4342 } else { 4343 CurContext->addDecl(New); 4344 } 4345 4346 // If this is the C FILE type, notify the AST context. 4347 if (IdentifierInfo *II = New->getIdentifier()) 4348 if (!New->isInvalidDecl() && 4349 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4350 II->isStr("FILE")) 4351 Context.setFILEDecl(New); 4352 4353 OwnedDecl = true; 4354 return DeclPtrTy::make(New); 4355} 4356 4357void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4358 AdjustDeclIfTemplate(TagD); 4359 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4360 4361 // Enter the tag context. 4362 PushDeclContext(S, Tag); 4363 4364 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4365 FieldCollector->StartClass(); 4366 4367 if (Record->getIdentifier()) { 4368 // C++ [class]p2: 4369 // [...] The class-name is also inserted into the scope of the 4370 // class itself; this is known as the injected-class-name. For 4371 // purposes of access checking, the injected-class-name is treated 4372 // as if it were a public member name. 4373 CXXRecordDecl *InjectedClassName 4374 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4375 CurContext, Record->getLocation(), 4376 Record->getIdentifier(), 4377 Record->getTagKeywordLoc(), 4378 Record); 4379 InjectedClassName->setImplicit(); 4380 InjectedClassName->setAccess(AS_public); 4381 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4382 InjectedClassName->setDescribedClassTemplate(Template); 4383 PushOnScopeChains(InjectedClassName, S); 4384 assert(InjectedClassName->isInjectedClassName() && 4385 "Broken injected-class-name"); 4386 } 4387 } 4388} 4389 4390void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4391 SourceLocation RBraceLoc) { 4392 AdjustDeclIfTemplate(TagD); 4393 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4394 Tag->setRBraceLoc(RBraceLoc); 4395 4396 if (isa<CXXRecordDecl>(Tag)) 4397 FieldCollector->FinishClass(); 4398 4399 // Exit this scope of this tag's definition. 4400 PopDeclContext(); 4401 4402 // Notify the consumer that we've defined a tag. 4403 Consumer.HandleTagDeclDefinition(Tag); 4404} 4405 4406// Note that FieldName may be null for anonymous bitfields. 4407bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4408 QualType FieldTy, const Expr *BitWidth, 4409 bool *ZeroWidth) { 4410 // Default to true; that shouldn't confuse checks for emptiness 4411 if (ZeroWidth) 4412 *ZeroWidth = true; 4413 4414 // C99 6.7.2.1p4 - verify the field type. 4415 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4416 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4417 // Handle incomplete types with specific error. 4418 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4419 return true; 4420 if (FieldName) 4421 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4422 << FieldName << FieldTy << BitWidth->getSourceRange(); 4423 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4424 << FieldTy << BitWidth->getSourceRange(); 4425 } 4426 4427 // If the bit-width is type- or value-dependent, don't try to check 4428 // it now. 4429 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4430 return false; 4431 4432 llvm::APSInt Value; 4433 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4434 return true; 4435 4436 if (Value != 0 && ZeroWidth) 4437 *ZeroWidth = false; 4438 4439 // Zero-width bitfield is ok for anonymous field. 4440 if (Value == 0 && FieldName) 4441 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4442 4443 if (Value.isSigned() && Value.isNegative()) { 4444 if (FieldName) 4445 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4446 << FieldName << Value.toString(10); 4447 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4448 << Value.toString(10); 4449 } 4450 4451 if (!FieldTy->isDependentType()) { 4452 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4453 if (Value.getZExtValue() > TypeSize) { 4454 if (FieldName) 4455 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4456 << FieldName << (unsigned)TypeSize; 4457 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4458 << (unsigned)TypeSize; 4459 } 4460 } 4461 4462 return false; 4463} 4464 4465/// ActOnField - Each field of a struct/union/class is passed into this in order 4466/// to create a FieldDecl object for it. 4467Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4468 SourceLocation DeclStart, 4469 Declarator &D, ExprTy *BitfieldWidth) { 4470 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4471 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4472 AS_public); 4473 return DeclPtrTy::make(Res); 4474} 4475 4476/// HandleField - Analyze a field of a C struct or a C++ data member. 4477/// 4478FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4479 SourceLocation DeclStart, 4480 Declarator &D, Expr *BitWidth, 4481 AccessSpecifier AS) { 4482 IdentifierInfo *II = D.getIdentifier(); 4483 SourceLocation Loc = DeclStart; 4484 if (II) Loc = D.getIdentifierLoc(); 4485 4486 DeclaratorInfo *DInfo = 0; 4487 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4488 if (getLangOptions().CPlusPlus) 4489 CheckExtraCXXDefaultArguments(D); 4490 4491 DiagnoseFunctionSpecifiers(D); 4492 4493 if (D.getDeclSpec().isThreadSpecified()) 4494 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4495 4496 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4497 4498 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4499 // Maybe we will complain about the shadowed template parameter. 4500 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4501 // Just pretend that we didn't see the previous declaration. 4502 PrevDecl = 0; 4503 } 4504 4505 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4506 PrevDecl = 0; 4507 4508 bool Mutable 4509 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4510 SourceLocation TSSL = D.getSourceRange().getBegin(); 4511 FieldDecl *NewFD 4512 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4513 AS, PrevDecl, &D); 4514 if (NewFD->isInvalidDecl() && PrevDecl) { 4515 // Don't introduce NewFD into scope; there's already something 4516 // with the same name in the same scope. 4517 } else if (II) { 4518 PushOnScopeChains(NewFD, S); 4519 } else 4520 Record->addDecl(NewFD); 4521 4522 return NewFD; 4523} 4524 4525/// \brief Build a new FieldDecl and check its well-formedness. 4526/// 4527/// This routine builds a new FieldDecl given the fields name, type, 4528/// record, etc. \p PrevDecl should refer to any previous declaration 4529/// with the same name and in the same scope as the field to be 4530/// created. 4531/// 4532/// \returns a new FieldDecl. 4533/// 4534/// \todo The Declarator argument is a hack. It will be removed once 4535FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4536 DeclaratorInfo *DInfo, 4537 RecordDecl *Record, SourceLocation Loc, 4538 bool Mutable, Expr *BitWidth, 4539 SourceLocation TSSL, 4540 AccessSpecifier AS, NamedDecl *PrevDecl, 4541 Declarator *D) { 4542 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4543 bool InvalidDecl = false; 4544 if (D) InvalidDecl = D->isInvalidType(); 4545 4546 // If we receive a broken type, recover by assuming 'int' and 4547 // marking this declaration as invalid. 4548 if (T.isNull()) { 4549 InvalidDecl = true; 4550 T = Context.IntTy; 4551 } 4552 4553 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4554 // than a variably modified type. 4555 if (T->isVariablyModifiedType()) { 4556 bool SizeIsNegative; 4557 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4558 SizeIsNegative); 4559 if (!FixedTy.isNull()) { 4560 Diag(Loc, diag::warn_illegal_constant_array_size); 4561 T = FixedTy; 4562 } else { 4563 if (SizeIsNegative) 4564 Diag(Loc, diag::err_typecheck_negative_array_size); 4565 else 4566 Diag(Loc, diag::err_typecheck_field_variable_size); 4567 InvalidDecl = true; 4568 } 4569 } 4570 4571 // Fields can not have abstract class types 4572 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4573 AbstractFieldType)) 4574 InvalidDecl = true; 4575 4576 bool ZeroWidth = false; 4577 // If this is declared as a bit-field, check the bit-field. 4578 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4579 InvalidDecl = true; 4580 DeleteExpr(BitWidth); 4581 BitWidth = 0; 4582 ZeroWidth = false; 4583 } 4584 4585 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4586 BitWidth, Mutable); 4587 if (InvalidDecl) 4588 NewFD->setInvalidDecl(); 4589 4590 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4591 Diag(Loc, diag::err_duplicate_member) << II; 4592 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4593 NewFD->setInvalidDecl(); 4594 } 4595 4596 if (getLangOptions().CPlusPlus) { 4597 QualType EltTy = Context.getBaseElementType(T); 4598 4599 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4600 4601 if (!T->isPODType()) 4602 CXXRecord->setPOD(false); 4603 if (!ZeroWidth) 4604 CXXRecord->setEmpty(false); 4605 4606 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4607 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4608 4609 if (!RDecl->hasTrivialConstructor()) 4610 CXXRecord->setHasTrivialConstructor(false); 4611 if (!RDecl->hasTrivialCopyConstructor()) 4612 CXXRecord->setHasTrivialCopyConstructor(false); 4613 if (!RDecl->hasTrivialCopyAssignment()) 4614 CXXRecord->setHasTrivialCopyAssignment(false); 4615 if (!RDecl->hasTrivialDestructor()) 4616 CXXRecord->setHasTrivialDestructor(false); 4617 4618 // C++ 9.5p1: An object of a class with a non-trivial 4619 // constructor, a non-trivial copy constructor, a non-trivial 4620 // destructor, or a non-trivial copy assignment operator 4621 // cannot be a member of a union, nor can an array of such 4622 // objects. 4623 // TODO: C++0x alters this restriction significantly. 4624 if (Record->isUnion()) { 4625 // We check for copy constructors before constructors 4626 // because otherwise we'll never get complaints about 4627 // copy constructors. 4628 4629 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4630 4631 CXXSpecialMember member; 4632 if (!RDecl->hasTrivialCopyConstructor()) 4633 member = CXXCopyConstructor; 4634 else if (!RDecl->hasTrivialConstructor()) 4635 member = CXXDefaultConstructor; 4636 else if (!RDecl->hasTrivialCopyAssignment()) 4637 member = CXXCopyAssignment; 4638 else if (!RDecl->hasTrivialDestructor()) 4639 member = CXXDestructor; 4640 else 4641 member = invalid; 4642 4643 if (member != invalid) { 4644 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4645 DiagnoseNontrivial(RT, member); 4646 NewFD->setInvalidDecl(); 4647 } 4648 } 4649 } 4650 } 4651 4652 // FIXME: We need to pass in the attributes given an AST 4653 // representation, not a parser representation. 4654 if (D) 4655 // FIXME: What to pass instead of TUScope? 4656 ProcessDeclAttributes(TUScope, NewFD, *D); 4657 4658 if (T.isObjCGCWeak()) 4659 Diag(Loc, diag::warn_attribute_weak_on_field); 4660 4661 NewFD->setAccess(AS); 4662 4663 // C++ [dcl.init.aggr]p1: 4664 // An aggregate is an array or a class (clause 9) with [...] no 4665 // private or protected non-static data members (clause 11). 4666 // A POD must be an aggregate. 4667 if (getLangOptions().CPlusPlus && 4668 (AS == AS_private || AS == AS_protected)) { 4669 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4670 CXXRecord->setAggregate(false); 4671 CXXRecord->setPOD(false); 4672 } 4673 4674 return NewFD; 4675} 4676 4677/// DiagnoseNontrivial - Given that a class has a non-trivial 4678/// special member, figure out why. 4679void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4680 QualType QT(T, 0U); 4681 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4682 4683 // Check whether the member was user-declared. 4684 switch (member) { 4685 case CXXDefaultConstructor: 4686 if (RD->hasUserDeclaredConstructor()) { 4687 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4688 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4689 if (!ci->isImplicitlyDefined(Context)) { 4690 SourceLocation CtorLoc = ci->getLocation(); 4691 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4692 return; 4693 } 4694 4695 assert(0 && "found no user-declared constructors"); 4696 return; 4697 } 4698 break; 4699 4700 case CXXCopyConstructor: 4701 if (RD->hasUserDeclaredCopyConstructor()) { 4702 SourceLocation CtorLoc = 4703 RD->getCopyConstructor(Context, 0)->getLocation(); 4704 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4705 return; 4706 } 4707 break; 4708 4709 case CXXCopyAssignment: 4710 if (RD->hasUserDeclaredCopyAssignment()) { 4711 // FIXME: this should use the location of the copy 4712 // assignment, not the type. 4713 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4714 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4715 return; 4716 } 4717 break; 4718 4719 case CXXDestructor: 4720 if (RD->hasUserDeclaredDestructor()) { 4721 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4722 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4723 return; 4724 } 4725 break; 4726 } 4727 4728 typedef CXXRecordDecl::base_class_iterator base_iter; 4729 4730 // Virtual bases and members inhibit trivial copying/construction, 4731 // but not trivial destruction. 4732 if (member != CXXDestructor) { 4733 // Check for virtual bases. vbases includes indirect virtual bases, 4734 // so we just iterate through the direct bases. 4735 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4736 if (bi->isVirtual()) { 4737 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4738 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4739 return; 4740 } 4741 4742 // Check for virtual methods. 4743 typedef CXXRecordDecl::method_iterator meth_iter; 4744 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4745 ++mi) { 4746 if (mi->isVirtual()) { 4747 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4748 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4749 return; 4750 } 4751 } 4752 } 4753 4754 bool (CXXRecordDecl::*hasTrivial)() const; 4755 switch (member) { 4756 case CXXDefaultConstructor: 4757 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4758 case CXXCopyConstructor: 4759 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4760 case CXXCopyAssignment: 4761 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4762 case CXXDestructor: 4763 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4764 default: 4765 assert(0 && "unexpected special member"); return; 4766 } 4767 4768 // Check for nontrivial bases (and recurse). 4769 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4770 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4771 assert(BaseRT); 4772 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4773 if (!(BaseRecTy->*hasTrivial)()) { 4774 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4775 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4776 DiagnoseNontrivial(BaseRT, member); 4777 return; 4778 } 4779 } 4780 4781 // Check for nontrivial members (and recurse). 4782 typedef RecordDecl::field_iterator field_iter; 4783 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4784 ++fi) { 4785 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4786 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4787 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4788 4789 if (!(EltRD->*hasTrivial)()) { 4790 SourceLocation FLoc = (*fi)->getLocation(); 4791 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4792 DiagnoseNontrivial(EltRT, member); 4793 return; 4794 } 4795 } 4796 } 4797 4798 assert(0 && "found no explanation for non-trivial member"); 4799} 4800 4801/// TranslateIvarVisibility - Translate visibility from a token ID to an 4802/// AST enum value. 4803static ObjCIvarDecl::AccessControl 4804TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4805 switch (ivarVisibility) { 4806 default: assert(0 && "Unknown visitibility kind"); 4807 case tok::objc_private: return ObjCIvarDecl::Private; 4808 case tok::objc_public: return ObjCIvarDecl::Public; 4809 case tok::objc_protected: return ObjCIvarDecl::Protected; 4810 case tok::objc_package: return ObjCIvarDecl::Package; 4811 } 4812} 4813 4814/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4815/// in order to create an IvarDecl object for it. 4816Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4817 SourceLocation DeclStart, 4818 DeclPtrTy IntfDecl, 4819 Declarator &D, ExprTy *BitfieldWidth, 4820 tok::ObjCKeywordKind Visibility) { 4821 4822 IdentifierInfo *II = D.getIdentifier(); 4823 Expr *BitWidth = (Expr*)BitfieldWidth; 4824 SourceLocation Loc = DeclStart; 4825 if (II) Loc = D.getIdentifierLoc(); 4826 4827 // FIXME: Unnamed fields can be handled in various different ways, for 4828 // example, unnamed unions inject all members into the struct namespace! 4829 4830 DeclaratorInfo *DInfo = 0; 4831 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4832 4833 if (BitWidth) { 4834 // 6.7.2.1p3, 6.7.2.1p4 4835 if (VerifyBitField(Loc, II, T, BitWidth)) { 4836 D.setInvalidType(); 4837 DeleteExpr(BitWidth); 4838 BitWidth = 0; 4839 } 4840 } else { 4841 // Not a bitfield. 4842 4843 // validate II. 4844 4845 } 4846 4847 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4848 // than a variably modified type. 4849 if (T->isVariablyModifiedType()) { 4850 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4851 D.setInvalidType(); 4852 } 4853 4854 // Get the visibility (access control) for this ivar. 4855 ObjCIvarDecl::AccessControl ac = 4856 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4857 : ObjCIvarDecl::None; 4858 // Must set ivar's DeclContext to its enclosing interface. 4859 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4860 DeclContext *EnclosingContext; 4861 if (ObjCImplementationDecl *IMPDecl = 4862 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4863 // Case of ivar declared in an implementation. Context is that of its class. 4864 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4865 assert(IDecl && "No class- ActOnIvar"); 4866 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4867 } else 4868 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4869 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4870 4871 // Construct the decl. 4872 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4873 EnclosingContext, Loc, II, T, 4874 DInfo, ac, (Expr *)BitfieldWidth); 4875 4876 if (II) { 4877 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4878 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4879 && !isa<TagDecl>(PrevDecl)) { 4880 Diag(Loc, diag::err_duplicate_member) << II; 4881 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4882 NewID->setInvalidDecl(); 4883 } 4884 } 4885 4886 // Process attributes attached to the ivar. 4887 ProcessDeclAttributes(S, NewID, D); 4888 4889 if (D.isInvalidType()) 4890 NewID->setInvalidDecl(); 4891 4892 if (II) { 4893 // FIXME: When interfaces are DeclContexts, we'll need to add 4894 // these to the interface. 4895 S->AddDecl(DeclPtrTy::make(NewID)); 4896 IdResolver.AddDecl(NewID); 4897 } 4898 4899 return DeclPtrTy::make(NewID); 4900} 4901 4902void Sema::ActOnFields(Scope* S, 4903 SourceLocation RecLoc, DeclPtrTy RecDecl, 4904 DeclPtrTy *Fields, unsigned NumFields, 4905 SourceLocation LBrac, SourceLocation RBrac, 4906 AttributeList *Attr) { 4907 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4908 assert(EnclosingDecl && "missing record or interface decl"); 4909 4910 // If the decl this is being inserted into is invalid, then it may be a 4911 // redeclaration or some other bogus case. Don't try to add fields to it. 4912 if (EnclosingDecl->isInvalidDecl()) { 4913 // FIXME: Deallocate fields? 4914 return; 4915 } 4916 4917 4918 // Verify that all the fields are okay. 4919 unsigned NumNamedMembers = 0; 4920 llvm::SmallVector<FieldDecl*, 32> RecFields; 4921 4922 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4923 for (unsigned i = 0; i != NumFields; ++i) { 4924 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4925 4926 // Get the type for the field. 4927 Type *FDTy = FD->getType().getTypePtr(); 4928 4929 if (!FD->isAnonymousStructOrUnion()) { 4930 // Remember all fields written by the user. 4931 RecFields.push_back(FD); 4932 } 4933 4934 // If the field is already invalid for some reason, don't emit more 4935 // diagnostics about it. 4936 if (FD->isInvalidDecl()) 4937 continue; 4938 4939 // C99 6.7.2.1p2: 4940 // A structure or union shall not contain a member with 4941 // incomplete or function type (hence, a structure shall not 4942 // contain an instance of itself, but may contain a pointer to 4943 // an instance of itself), except that the last member of a 4944 // structure with more than one named member may have incomplete 4945 // array type; such a structure (and any union containing, 4946 // possibly recursively, a member that is such a structure) 4947 // shall not be a member of a structure or an element of an 4948 // array. 4949 if (FDTy->isFunctionType()) { 4950 // Field declared as a function. 4951 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4952 << FD->getDeclName(); 4953 FD->setInvalidDecl(); 4954 EnclosingDecl->setInvalidDecl(); 4955 continue; 4956 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4957 Record && Record->isStruct()) { 4958 // Flexible array member. 4959 if (NumNamedMembers < 1) { 4960 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4961 << FD->getDeclName(); 4962 FD->setInvalidDecl(); 4963 EnclosingDecl->setInvalidDecl(); 4964 continue; 4965 } 4966 // Okay, we have a legal flexible array member at the end of the struct. 4967 if (Record) 4968 Record->setHasFlexibleArrayMember(true); 4969 } else if (!FDTy->isDependentType() && 4970 RequireCompleteType(FD->getLocation(), FD->getType(), 4971 diag::err_field_incomplete)) { 4972 // Incomplete type 4973 FD->setInvalidDecl(); 4974 EnclosingDecl->setInvalidDecl(); 4975 continue; 4976 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 4977 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4978 // If this is a member of a union, then entire union becomes "flexible". 4979 if (Record && Record->isUnion()) { 4980 Record->setHasFlexibleArrayMember(true); 4981 } else { 4982 // If this is a struct/class and this is not the last element, reject 4983 // it. Note that GCC supports variable sized arrays in the middle of 4984 // structures. 4985 if (i != NumFields-1) 4986 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4987 << FD->getDeclName() << FD->getType(); 4988 else { 4989 // We support flexible arrays at the end of structs in 4990 // other structs as an extension. 4991 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4992 << FD->getDeclName(); 4993 if (Record) 4994 Record->setHasFlexibleArrayMember(true); 4995 } 4996 } 4997 } 4998 if (Record && FDTTy->getDecl()->hasObjectMember()) 4999 Record->setHasObjectMember(true); 5000 } else if (FDTy->isObjCInterfaceType()) { 5001 /// A field cannot be an Objective-c object 5002 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5003 FD->setInvalidDecl(); 5004 EnclosingDecl->setInvalidDecl(); 5005 continue; 5006 } else if (getLangOptions().ObjC1 && 5007 getLangOptions().getGCMode() != LangOptions::NonGC && 5008 Record && 5009 (FD->getType()->isObjCObjectPointerType() || 5010 FD->getType().isObjCGCStrong())) 5011 Record->setHasObjectMember(true); 5012 // Keep track of the number of named members. 5013 if (FD->getIdentifier()) 5014 ++NumNamedMembers; 5015 } 5016 5017 // Okay, we successfully defined 'Record'. 5018 if (Record) { 5019 Record->completeDefinition(Context); 5020 } else { 5021 ObjCIvarDecl **ClsFields = 5022 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5023 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5024 ID->setIVarList(ClsFields, RecFields.size(), Context); 5025 ID->setLocEnd(RBrac); 5026 // Add ivar's to class's DeclContext. 5027 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5028 ClsFields[i]->setLexicalDeclContext(ID); 5029 ID->addDecl(ClsFields[i]); 5030 } 5031 // Must enforce the rule that ivars in the base classes may not be 5032 // duplicates. 5033 if (ID->getSuperClass()) { 5034 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5035 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5036 ObjCIvarDecl* Ivar = (*IVI); 5037 5038 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5039 ObjCIvarDecl* prevIvar = 5040 ID->getSuperClass()->lookupInstanceVariable(II); 5041 if (prevIvar) { 5042 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5043 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5044 } 5045 } 5046 } 5047 } 5048 } else if (ObjCImplementationDecl *IMPDecl = 5049 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5050 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5051 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5052 // Ivar declared in @implementation never belongs to the implementation. 5053 // Only it is in implementation's lexical context. 5054 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5055 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5056 } 5057 } 5058 5059 if (Attr) 5060 ProcessDeclAttributeList(S, Record, Attr); 5061} 5062 5063EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5064 EnumConstantDecl *LastEnumConst, 5065 SourceLocation IdLoc, 5066 IdentifierInfo *Id, 5067 ExprArg val) { 5068 Expr *Val = (Expr *)val.get(); 5069 5070 llvm::APSInt EnumVal(32); 5071 QualType EltTy; 5072 if (Val && !Val->isTypeDependent()) { 5073 // Make sure to promote the operand type to int. 5074 UsualUnaryConversions(Val); 5075 if (Val != val.get()) { 5076 val.release(); 5077 val = Val; 5078 } 5079 5080 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5081 SourceLocation ExpLoc; 5082 if (!Val->isValueDependent() && 5083 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5084 Val = 0; 5085 } else { 5086 EltTy = Val->getType(); 5087 } 5088 } 5089 5090 if (!Val) { 5091 if (LastEnumConst) { 5092 // Assign the last value + 1. 5093 EnumVal = LastEnumConst->getInitVal(); 5094 ++EnumVal; 5095 5096 // Check for overflow on increment. 5097 if (EnumVal < LastEnumConst->getInitVal()) 5098 Diag(IdLoc, diag::warn_enum_value_overflow); 5099 5100 EltTy = LastEnumConst->getType(); 5101 } else { 5102 // First value, set to zero. 5103 EltTy = Context.IntTy; 5104 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5105 } 5106 } 5107 5108 val.release(); 5109 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5110 Val, EnumVal); 5111} 5112 5113 5114Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5115 DeclPtrTy lastEnumConst, 5116 SourceLocation IdLoc, 5117 IdentifierInfo *Id, 5118 SourceLocation EqualLoc, ExprTy *val) { 5119 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5120 EnumConstantDecl *LastEnumConst = 5121 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5122 Expr *Val = static_cast<Expr*>(val); 5123 5124 // The scope passed in may not be a decl scope. Zip up the scope tree until 5125 // we find one that is. 5126 S = getNonFieldDeclScope(S); 5127 5128 // Verify that there isn't already something declared with this name in this 5129 // scope. 5130 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5131 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5132 // Maybe we will complain about the shadowed template parameter. 5133 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5134 // Just pretend that we didn't see the previous declaration. 5135 PrevDecl = 0; 5136 } 5137 5138 if (PrevDecl) { 5139 // When in C++, we may get a TagDecl with the same name; in this case the 5140 // enum constant will 'hide' the tag. 5141 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5142 "Received TagDecl when not in C++!"); 5143 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5144 if (isa<EnumConstantDecl>(PrevDecl)) 5145 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5146 else 5147 Diag(IdLoc, diag::err_redefinition) << Id; 5148 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5149 if (Val) Val->Destroy(Context); 5150 return DeclPtrTy(); 5151 } 5152 } 5153 5154 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5155 IdLoc, Id, Owned(Val)); 5156 5157 // Register this decl in the current scope stack. 5158 if (New) 5159 PushOnScopeChains(New, S); 5160 5161 return DeclPtrTy::make(New); 5162} 5163 5164void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5165 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5166 DeclPtrTy *Elements, unsigned NumElements, 5167 Scope *S, AttributeList *Attr) { 5168 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5169 QualType EnumType = Context.getTypeDeclType(Enum); 5170 5171 if (Attr) 5172 ProcessDeclAttributeList(S, Enum, Attr); 5173 5174 // TODO: If the result value doesn't fit in an int, it must be a long or long 5175 // long value. ISO C does not support this, but GCC does as an extension, 5176 // emit a warning. 5177 unsigned IntWidth = Context.Target.getIntWidth(); 5178 unsigned CharWidth = Context.Target.getCharWidth(); 5179 unsigned ShortWidth = Context.Target.getShortWidth(); 5180 5181 // Verify that all the values are okay, compute the size of the values, and 5182 // reverse the list. 5183 unsigned NumNegativeBits = 0; 5184 unsigned NumPositiveBits = 0; 5185 5186 // Keep track of whether all elements have type int. 5187 bool AllElementsInt = true; 5188 5189 for (unsigned i = 0; i != NumElements; ++i) { 5190 EnumConstantDecl *ECD = 5191 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5192 if (!ECD) continue; // Already issued a diagnostic. 5193 5194 // If the enum value doesn't fit in an int, emit an extension warning. 5195 const llvm::APSInt &InitVal = ECD->getInitVal(); 5196 assert(InitVal.getBitWidth() >= IntWidth && 5197 "Should have promoted value to int"); 5198 if (InitVal.getBitWidth() > IntWidth) { 5199 llvm::APSInt V(InitVal); 5200 V.trunc(IntWidth); 5201 V.extend(InitVal.getBitWidth()); 5202 if (V != InitVal) 5203 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5204 << InitVal.toString(10); 5205 } 5206 5207 // Keep track of the size of positive and negative values. 5208 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5209 NumPositiveBits = std::max(NumPositiveBits, 5210 (unsigned)InitVal.getActiveBits()); 5211 else 5212 NumNegativeBits = std::max(NumNegativeBits, 5213 (unsigned)InitVal.getMinSignedBits()); 5214 5215 // Keep track of whether every enum element has type int (very commmon). 5216 if (AllElementsInt) 5217 AllElementsInt = ECD->getType() == Context.IntTy; 5218 } 5219 5220 // Figure out the type that should be used for this enum. 5221 // FIXME: Support -fshort-enums. 5222 QualType BestType; 5223 unsigned BestWidth; 5224 5225 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5226 5227 if (NumNegativeBits) { 5228 // If there is a negative value, figure out the smallest integer type (of 5229 // int/long/longlong) that fits. 5230 // If it's packed, check also if it fits a char or a short. 5231 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5232 BestType = Context.SignedCharTy; 5233 BestWidth = CharWidth; 5234 } else if (Packed && NumNegativeBits <= ShortWidth && 5235 NumPositiveBits < ShortWidth) { 5236 BestType = Context.ShortTy; 5237 BestWidth = ShortWidth; 5238 } 5239 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5240 BestType = Context.IntTy; 5241 BestWidth = IntWidth; 5242 } else { 5243 BestWidth = Context.Target.getLongWidth(); 5244 5245 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5246 BestType = Context.LongTy; 5247 else { 5248 BestWidth = Context.Target.getLongLongWidth(); 5249 5250 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5251 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5252 BestType = Context.LongLongTy; 5253 } 5254 } 5255 } else { 5256 // If there is no negative value, figure out which of uint, ulong, ulonglong 5257 // fits. 5258 // If it's packed, check also if it fits a char or a short. 5259 if (Packed && NumPositiveBits <= CharWidth) { 5260 BestType = Context.UnsignedCharTy; 5261 BestWidth = CharWidth; 5262 } else if (Packed && NumPositiveBits <= ShortWidth) { 5263 BestType = Context.UnsignedShortTy; 5264 BestWidth = ShortWidth; 5265 } 5266 else if (NumPositiveBits <= IntWidth) { 5267 BestType = Context.UnsignedIntTy; 5268 BestWidth = IntWidth; 5269 } else if (NumPositiveBits <= 5270 (BestWidth = Context.Target.getLongWidth())) { 5271 BestType = Context.UnsignedLongTy; 5272 } else { 5273 BestWidth = Context.Target.getLongLongWidth(); 5274 assert(NumPositiveBits <= BestWidth && 5275 "How could an initializer get larger than ULL?"); 5276 BestType = Context.UnsignedLongLongTy; 5277 } 5278 } 5279 5280 // Loop over all of the enumerator constants, changing their types to match 5281 // the type of the enum if needed. 5282 for (unsigned i = 0; i != NumElements; ++i) { 5283 EnumConstantDecl *ECD = 5284 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5285 if (!ECD) continue; // Already issued a diagnostic. 5286 5287 // Standard C says the enumerators have int type, but we allow, as an 5288 // extension, the enumerators to be larger than int size. If each 5289 // enumerator value fits in an int, type it as an int, otherwise type it the 5290 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5291 // that X has type 'int', not 'unsigned'. 5292 if (ECD->getType() == Context.IntTy) { 5293 // Make sure the init value is signed. 5294 llvm::APSInt IV = ECD->getInitVal(); 5295 IV.setIsSigned(true); 5296 ECD->setInitVal(IV); 5297 5298 if (getLangOptions().CPlusPlus) 5299 // C++ [dcl.enum]p4: Following the closing brace of an 5300 // enum-specifier, each enumerator has the type of its 5301 // enumeration. 5302 ECD->setType(EnumType); 5303 continue; // Already int type. 5304 } 5305 5306 // Determine whether the value fits into an int. 5307 llvm::APSInt InitVal = ECD->getInitVal(); 5308 bool FitsInInt; 5309 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5310 FitsInInt = InitVal.getActiveBits() < IntWidth; 5311 else 5312 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5313 5314 // If it fits into an integer type, force it. Otherwise force it to match 5315 // the enum decl type. 5316 QualType NewTy; 5317 unsigned NewWidth; 5318 bool NewSign; 5319 if (FitsInInt) { 5320 NewTy = Context.IntTy; 5321 NewWidth = IntWidth; 5322 NewSign = true; 5323 } else if (ECD->getType() == BestType) { 5324 // Already the right type! 5325 if (getLangOptions().CPlusPlus) 5326 // C++ [dcl.enum]p4: Following the closing brace of an 5327 // enum-specifier, each enumerator has the type of its 5328 // enumeration. 5329 ECD->setType(EnumType); 5330 continue; 5331 } else { 5332 NewTy = BestType; 5333 NewWidth = BestWidth; 5334 NewSign = BestType->isSignedIntegerType(); 5335 } 5336 5337 // Adjust the APSInt value. 5338 InitVal.extOrTrunc(NewWidth); 5339 InitVal.setIsSigned(NewSign); 5340 ECD->setInitVal(InitVal); 5341 5342 // Adjust the Expr initializer and type. 5343 if (ECD->getInitExpr()) 5344 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5345 CastExpr::CK_Unknown, 5346 ECD->getInitExpr(), 5347 /*isLvalue=*/false)); 5348 if (getLangOptions().CPlusPlus) 5349 // C++ [dcl.enum]p4: Following the closing brace of an 5350 // enum-specifier, each enumerator has the type of its 5351 // enumeration. 5352 ECD->setType(EnumType); 5353 else 5354 ECD->setType(NewTy); 5355 } 5356 5357 Enum->completeDefinition(Context, BestType); 5358} 5359 5360Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5361 ExprArg expr) { 5362 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5363 5364 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5365 Loc, AsmString); 5366 CurContext->addDecl(New); 5367 return DeclPtrTy::make(New); 5368} 5369 5370void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5371 SourceLocation PragmaLoc, 5372 SourceLocation NameLoc) { 5373 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5374 5375 if (PrevDecl) { 5376 PrevDecl->addAttr(::new (Context) WeakAttr()); 5377 } else { 5378 (void)WeakUndeclaredIdentifiers.insert( 5379 std::pair<IdentifierInfo*,WeakInfo> 5380 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5381 } 5382} 5383 5384void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5385 IdentifierInfo* AliasName, 5386 SourceLocation PragmaLoc, 5387 SourceLocation NameLoc, 5388 SourceLocation AliasNameLoc) { 5389 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5390 WeakInfo W = WeakInfo(Name, NameLoc); 5391 5392 if (PrevDecl) { 5393 if (!PrevDecl->hasAttr<AliasAttr>()) 5394 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5395 DeclApplyPragmaWeak(TUScope, ND, W); 5396 } else { 5397 (void)WeakUndeclaredIdentifiers.insert( 5398 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5399 } 5400} 5401