SemaDecl.cpp revision f6d6a228b0faafdfd1cdffe865f47616b6cab7a8
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/TargetInfo.h" 27#include "clang/Basic/SourceManager.h" 28// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 29#include "clang/Lex/Preprocessor.h" 30#include "clang/Lex/HeaderSearch.h" 31#include "llvm/ADT/BitVector.h" 32#include "llvm/ADT/STLExtras.h" 33#include <algorithm> 34#include <functional> 35#include <queue> 36using namespace clang; 37 38/// getDeclName - Return a pretty name for the specified decl if possible, or 39/// an empty string if not. This is used for pretty crash reporting. 40std::string Sema::getDeclName(DeclPtrTy d) { 41 Decl *D = d.getAs<Decl>(); 42 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 43 return DN->getQualifiedNameAsString(); 44 return ""; 45} 46 47Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 48 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 49} 50 51/// \brief If the identifier refers to a type name within this scope, 52/// return the declaration of that type. 53/// 54/// This routine performs ordinary name lookup of the identifier II 55/// within the given scope, with optional C++ scope specifier SS, to 56/// determine whether the name refers to a type. If so, returns an 57/// opaque pointer (actually a QualType) corresponding to that 58/// type. Otherwise, returns NULL. 59/// 60/// If name lookup results in an ambiguity, this routine will complain 61/// and then return NULL. 62Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 63 Scope *S, const CXXScopeSpec *SS) { 64 // C++ [temp.res]p3: 65 // A qualified-id that refers to a type and in which the 66 // nested-name-specifier depends on a template-parameter (14.6.2) 67 // shall be prefixed by the keyword typename to indicate that the 68 // qualified-id denotes a type, forming an 69 // elaborated-type-specifier (7.1.5.3). 70 // 71 // We therefore do not perform any name lookup if the result would 72 // refer to a member of an unknown specialization. 73 if (SS && isUnknownSpecialization(*SS)) 74 return 0; 75 76 LookupResult Result 77 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 78 79 NamedDecl *IIDecl = 0; 80 switch (Result.getKind()) { 81 case LookupResult::NotFound: 82 case LookupResult::FoundOverloaded: 83 return 0; 84 85 case LookupResult::AmbiguousBaseSubobjectTypes: 86 case LookupResult::AmbiguousBaseSubobjects: 87 case LookupResult::AmbiguousReference: { 88 // Look to see if we have a type anywhere in the list of results. 89 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 90 Res != ResEnd; ++Res) { 91 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 92 if (!IIDecl || 93 (*Res)->getLocation().getRawEncoding() < 94 IIDecl->getLocation().getRawEncoding()) 95 IIDecl = *Res; 96 } 97 } 98 99 if (!IIDecl) { 100 // None of the entities we found is a type, so there is no way 101 // to even assume that the result is a type. In this case, don't 102 // complain about the ambiguity. The parser will either try to 103 // perform this lookup again (e.g., as an object name), which 104 // will produce the ambiguity, or will complain that it expected 105 // a type name. 106 Result.Destroy(); 107 return 0; 108 } 109 110 // We found a type within the ambiguous lookup; diagnose the 111 // ambiguity and then return that type. This might be the right 112 // answer, or it might not be, but it suppresses any attempt to 113 // perform the name lookup again. 114 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 115 break; 116 } 117 118 case LookupResult::Found: 119 IIDecl = Result.getAsDecl(); 120 break; 121 } 122 123 if (IIDecl) { 124 QualType T; 125 126 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 127 // Check whether we can use this type 128 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 129 130 if (getLangOptions().CPlusPlus) { 131 // C++ [temp.local]p2: 132 // Within the scope of a class template specialization or 133 // partial specialization, when the injected-class-name is 134 // not followed by a <, it is equivalent to the 135 // injected-class-name followed by the template-argument s 136 // of the class template specialization or partial 137 // specialization enclosed in <>. 138 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 139 if (RD->isInjectedClassName()) 140 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 141 T = Template->getInjectedClassNameType(Context); 142 } 143 144 if (T.isNull()) 145 T = Context.getTypeDeclType(TD); 146 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 147 // Check whether we can use this interface. 148 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 149 150 T = Context.getObjCInterfaceType(IDecl); 151 } else 152 return 0; 153 154 if (SS) 155 T = getQualifiedNameType(*SS, T); 156 157 return T.getAsOpaquePtr(); 158 } 159 160 return 0; 161} 162 163/// isTagName() - This method is called *for error recovery purposes only* 164/// to determine if the specified name is a valid tag name ("struct foo"). If 165/// so, this returns the TST for the tag corresponding to it (TST_enum, 166/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 167/// where the user forgot to specify the tag. 168DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 169 // Do a tag name lookup in this scope. 170 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 171 if (R.getKind() == LookupResult::Found) 172 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 173 switch (TD->getTagKind()) { 174 case TagDecl::TK_struct: return DeclSpec::TST_struct; 175 case TagDecl::TK_union: return DeclSpec::TST_union; 176 case TagDecl::TK_class: return DeclSpec::TST_class; 177 case TagDecl::TK_enum: return DeclSpec::TST_enum; 178 } 179 } 180 181 return DeclSpec::TST_unspecified; 182} 183 184 185// Determines the context to return to after temporarily entering a 186// context. This depends in an unnecessarily complicated way on the 187// exact ordering of callbacks from the parser. 188DeclContext *Sema::getContainingDC(DeclContext *DC) { 189 190 // Functions defined inline within classes aren't parsed until we've 191 // finished parsing the top-level class, so the top-level class is 192 // the context we'll need to return to. 193 if (isa<FunctionDecl>(DC)) { 194 DC = DC->getLexicalParent(); 195 196 // A function not defined within a class will always return to its 197 // lexical context. 198 if (!isa<CXXRecordDecl>(DC)) 199 return DC; 200 201 // A C++ inline method/friend is parsed *after* the topmost class 202 // it was declared in is fully parsed ("complete"); the topmost 203 // class is the context we need to return to. 204 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 205 DC = RD; 206 207 // Return the declaration context of the topmost class the inline method is 208 // declared in. 209 return DC; 210 } 211 212 if (isa<ObjCMethodDecl>(DC)) 213 return Context.getTranslationUnitDecl(); 214 215 return DC->getLexicalParent(); 216} 217 218void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 219 assert(getContainingDC(DC) == CurContext && 220 "The next DeclContext should be lexically contained in the current one."); 221 CurContext = DC; 222 S->setEntity(DC); 223} 224 225void Sema::PopDeclContext() { 226 assert(CurContext && "DeclContext imbalance!"); 227 228 CurContext = getContainingDC(CurContext); 229} 230 231/// EnterDeclaratorContext - Used when we must lookup names in the context 232/// of a declarator's nested name specifier. 233void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 234 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 235 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 236 CurContext = DC; 237 assert(CurContext && "No context?"); 238 S->setEntity(CurContext); 239} 240 241void Sema::ExitDeclaratorContext(Scope *S) { 242 S->setEntity(PreDeclaratorDC); 243 PreDeclaratorDC = 0; 244 245 // Reset CurContext to the nearest enclosing context. 246 while (!S->getEntity() && S->getParent()) 247 S = S->getParent(); 248 CurContext = static_cast<DeclContext*>(S->getEntity()); 249 assert(CurContext && "No context?"); 250} 251 252/// \brief Determine whether we allow overloading of the function 253/// PrevDecl with another declaration. 254/// 255/// This routine determines whether overloading is possible, not 256/// whether some new function is actually an overload. It will return 257/// true in C++ (where we can always provide overloads) or, as an 258/// extension, in C when the previous function is already an 259/// overloaded function declaration or has the "overloadable" 260/// attribute. 261static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 262 if (Context.getLangOptions().CPlusPlus) 263 return true; 264 265 if (isa<OverloadedFunctionDecl>(PrevDecl)) 266 return true; 267 268 return PrevDecl->getAttr<OverloadableAttr>() != 0; 269} 270 271/// Add this decl to the scope shadowed decl chains. 272void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 273 // Move up the scope chain until we find the nearest enclosing 274 // non-transparent context. The declaration will be introduced into this 275 // scope. 276 while (S->getEntity() && 277 ((DeclContext *)S->getEntity())->isTransparentContext()) 278 S = S->getParent(); 279 280 S->AddDecl(DeclPtrTy::make(D)); 281 282 // Add scoped declarations into their context, so that they can be 283 // found later. Declarations without a context won't be inserted 284 // into any context. 285 CurContext->addDecl(D); 286 287 // C++ [basic.scope]p4: 288 // -- exactly one declaration shall declare a class name or 289 // enumeration name that is not a typedef name and the other 290 // declarations shall all refer to the same object or 291 // enumerator, or all refer to functions and function templates; 292 // in this case the class name or enumeration name is hidden. 293 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 294 // We are pushing the name of a tag (enum or class). 295 if (CurContext->getLookupContext() 296 == TD->getDeclContext()->getLookupContext()) { 297 // We're pushing the tag into the current context, which might 298 // require some reshuffling in the identifier resolver. 299 IdentifierResolver::iterator 300 I = IdResolver.begin(TD->getDeclName()), 301 IEnd = IdResolver.end(); 302 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 303 NamedDecl *PrevDecl = *I; 304 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 305 PrevDecl = *I, ++I) { 306 if (TD->declarationReplaces(*I)) { 307 // This is a redeclaration. Remove it from the chain and 308 // break out, so that we'll add in the shadowed 309 // declaration. 310 S->RemoveDecl(DeclPtrTy::make(*I)); 311 if (PrevDecl == *I) { 312 IdResolver.RemoveDecl(*I); 313 IdResolver.AddDecl(TD); 314 return; 315 } else { 316 IdResolver.RemoveDecl(*I); 317 break; 318 } 319 } 320 } 321 322 // There is already a declaration with the same name in the same 323 // scope, which is not a tag declaration. It must be found 324 // before we find the new declaration, so insert the new 325 // declaration at the end of the chain. 326 IdResolver.AddShadowedDecl(TD, PrevDecl); 327 328 return; 329 } 330 } 331 } else if ((isa<FunctionDecl>(D) && 332 AllowOverloadingOfFunction(D, Context)) || 333 isa<FunctionTemplateDecl>(D)) { 334 // We are pushing the name of a function or function template, 335 // which might be an overloaded name. 336 IdentifierResolver::iterator Redecl 337 = std::find_if(IdResolver.begin(D->getDeclName()), 338 IdResolver.end(), 339 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 340 D)); 341 if (Redecl != IdResolver.end() && 342 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 343 // There is already a declaration of a function on our 344 // IdResolver chain. Replace it with this declaration. 345 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 346 IdResolver.RemoveDecl(*Redecl); 347 } 348 } else if (isa<ObjCInterfaceDecl>(D)) { 349 // We're pushing an Objective-C interface into the current 350 // context. If there is already an alias declaration, remove it first. 351 for (IdentifierResolver::iterator 352 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 353 I != IEnd; ++I) { 354 if (isa<ObjCCompatibleAliasDecl>(*I)) { 355 S->RemoveDecl(DeclPtrTy::make(*I)); 356 IdResolver.RemoveDecl(*I); 357 break; 358 } 359 } 360 } 361 362 IdResolver.AddDecl(D); 363} 364 365void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 366 if (S->decl_empty()) return; 367 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 368 "Scope shouldn't contain decls!"); 369 370 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 371 I != E; ++I) { 372 Decl *TmpD = (*I).getAs<Decl>(); 373 assert(TmpD && "This decl didn't get pushed??"); 374 375 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 376 NamedDecl *D = cast<NamedDecl>(TmpD); 377 378 if (!D->getDeclName()) continue; 379 380 // Remove this name from our lexical scope. 381 IdResolver.RemoveDecl(D); 382 } 383} 384 385/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 386/// return 0 if one not found. 387ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 388 // The third "scope" argument is 0 since we aren't enabling lazy built-in 389 // creation from this context. 390 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 391 392 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 393} 394 395/// getNonFieldDeclScope - Retrieves the innermost scope, starting 396/// from S, where a non-field would be declared. This routine copes 397/// with the difference between C and C++ scoping rules in structs and 398/// unions. For example, the following code is well-formed in C but 399/// ill-formed in C++: 400/// @code 401/// struct S6 { 402/// enum { BAR } e; 403/// }; 404/// 405/// void test_S6() { 406/// struct S6 a; 407/// a.e = BAR; 408/// } 409/// @endcode 410/// For the declaration of BAR, this routine will return a different 411/// scope. The scope S will be the scope of the unnamed enumeration 412/// within S6. In C++, this routine will return the scope associated 413/// with S6, because the enumeration's scope is a transparent 414/// context but structures can contain non-field names. In C, this 415/// routine will return the translation unit scope, since the 416/// enumeration's scope is a transparent context and structures cannot 417/// contain non-field names. 418Scope *Sema::getNonFieldDeclScope(Scope *S) { 419 while (((S->getFlags() & Scope::DeclScope) == 0) || 420 (S->getEntity() && 421 ((DeclContext *)S->getEntity())->isTransparentContext()) || 422 (S->isClassScope() && !getLangOptions().CPlusPlus)) 423 S = S->getParent(); 424 return S; 425} 426 427void Sema::InitBuiltinVaListType() { 428 if (!Context.getBuiltinVaListType().isNull()) 429 return; 430 431 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 432 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 433 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 434 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 435} 436 437/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 438/// file scope. lazily create a decl for it. ForRedeclaration is true 439/// if we're creating this built-in in anticipation of redeclaring the 440/// built-in. 441NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 442 Scope *S, bool ForRedeclaration, 443 SourceLocation Loc) { 444 Builtin::ID BID = (Builtin::ID)bid; 445 446 if (Context.BuiltinInfo.hasVAListUse(BID)) 447 InitBuiltinVaListType(); 448 449 ASTContext::GetBuiltinTypeError Error; 450 QualType R = Context.GetBuiltinType(BID, Error); 451 switch (Error) { 452 case ASTContext::GE_None: 453 // Okay 454 break; 455 456 case ASTContext::GE_Missing_stdio: 457 if (ForRedeclaration) 458 Diag(Loc, diag::err_implicit_decl_requires_stdio) 459 << Context.BuiltinInfo.GetName(BID); 460 return 0; 461 462 case ASTContext::GE_Missing_setjmp: 463 if (ForRedeclaration) 464 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 465 << Context.BuiltinInfo.GetName(BID); 466 return 0; 467 } 468 469 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 470 Diag(Loc, diag::ext_implicit_lib_function_decl) 471 << Context.BuiltinInfo.GetName(BID) 472 << R; 473 if (Context.BuiltinInfo.getHeaderName(BID) && 474 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 475 != Diagnostic::Ignored) 476 Diag(Loc, diag::note_please_include_header) 477 << Context.BuiltinInfo.getHeaderName(BID) 478 << Context.BuiltinInfo.GetName(BID); 479 } 480 481 FunctionDecl *New = FunctionDecl::Create(Context, 482 Context.getTranslationUnitDecl(), 483 Loc, II, R, /*DInfo=*/0, 484 FunctionDecl::Extern, false, 485 /*hasPrototype=*/true); 486 New->setImplicit(); 487 488 // Create Decl objects for each parameter, adding them to the 489 // FunctionDecl. 490 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 491 llvm::SmallVector<ParmVarDecl*, 16> Params; 492 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 493 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 494 FT->getArgType(i), /*DInfo=*/0, 495 VarDecl::None, 0)); 496 New->setParams(Context, Params.data(), Params.size()); 497 } 498 499 AddKnownFunctionAttributes(New); 500 501 // TUScope is the translation-unit scope to insert this function into. 502 // FIXME: This is hideous. We need to teach PushOnScopeChains to 503 // relate Scopes to DeclContexts, and probably eliminate CurContext 504 // entirely, but we're not there yet. 505 DeclContext *SavedContext = CurContext; 506 CurContext = Context.getTranslationUnitDecl(); 507 PushOnScopeChains(New, TUScope); 508 CurContext = SavedContext; 509 return New; 510} 511 512/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 513/// everything from the standard library is defined. 514NamespaceDecl *Sema::GetStdNamespace() { 515 if (!StdNamespace) { 516 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 517 DeclContext *Global = Context.getTranslationUnitDecl(); 518 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 519 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 520 } 521 return StdNamespace; 522} 523 524/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 525/// same name and scope as a previous declaration 'Old'. Figure out 526/// how to resolve this situation, merging decls or emitting 527/// diagnostics as appropriate. If there was an error, set New to be invalid. 528/// 529void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 530 // If either decl is known invalid already, set the new one to be invalid and 531 // don't bother doing any merging checks. 532 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 533 return New->setInvalidDecl(); 534 535 // Allow multiple definitions for ObjC built-in typedefs. 536 // FIXME: Verify the underlying types are equivalent! 537 if (getLangOptions().ObjC1) { 538 const IdentifierInfo *TypeID = New->getIdentifier(); 539 switch (TypeID->getLength()) { 540 default: break; 541 case 2: 542 if (!TypeID->isStr("id")) 543 break; 544 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 545 // Install the built-in type for 'id', ignoring the current definition. 546 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 547 return; 548 case 5: 549 if (!TypeID->isStr("Class")) 550 break; 551 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 552 // Install the built-in type for 'Class', ignoring the current definition. 553 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 554 return; 555 case 3: 556 if (!TypeID->isStr("SEL")) 557 break; 558 Context.setObjCSelType(Context.getTypeDeclType(New)); 559 return; 560 case 8: 561 if (!TypeID->isStr("Protocol")) 562 break; 563 Context.setObjCProtoType(New->getUnderlyingType()); 564 return; 565 } 566 // Fall through - the typedef name was not a builtin type. 567 } 568 // Verify the old decl was also a type. 569 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 570 if (!Old) { 571 Diag(New->getLocation(), diag::err_redefinition_different_kind) 572 << New->getDeclName(); 573 if (OldD->getLocation().isValid()) 574 Diag(OldD->getLocation(), diag::note_previous_definition); 575 return New->setInvalidDecl(); 576 } 577 578 // Determine the "old" type we'll use for checking and diagnostics. 579 QualType OldType; 580 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 581 OldType = OldTypedef->getUnderlyingType(); 582 else 583 OldType = Context.getTypeDeclType(Old); 584 585 // If the typedef types are not identical, reject them in all languages and 586 // with any extensions enabled. 587 588 if (OldType != New->getUnderlyingType() && 589 Context.getCanonicalType(OldType) != 590 Context.getCanonicalType(New->getUnderlyingType())) { 591 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 592 << New->getUnderlyingType() << OldType; 593 if (Old->getLocation().isValid()) 594 Diag(Old->getLocation(), diag::note_previous_definition); 595 return New->setInvalidDecl(); 596 } 597 598 if (getLangOptions().Microsoft) 599 return; 600 601 // C++ [dcl.typedef]p2: 602 // In a given non-class scope, a typedef specifier can be used to 603 // redefine the name of any type declared in that scope to refer 604 // to the type to which it already refers. 605 if (getLangOptions().CPlusPlus) { 606 if (!isa<CXXRecordDecl>(CurContext)) 607 return; 608 Diag(New->getLocation(), diag::err_redefinition) 609 << New->getDeclName(); 610 Diag(Old->getLocation(), diag::note_previous_definition); 611 return New->setInvalidDecl(); 612 } 613 614 // If we have a redefinition of a typedef in C, emit a warning. This warning 615 // is normally mapped to an error, but can be controlled with 616 // -Wtypedef-redefinition. If either the original or the redefinition is 617 // in a system header, don't emit this for compatibility with GCC. 618 if (PP.getDiagnostics().getSuppressSystemWarnings() && 619 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 620 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 621 return; 622 623 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 624 << New->getDeclName(); 625 Diag(Old->getLocation(), diag::note_previous_definition); 626 return; 627} 628 629/// DeclhasAttr - returns true if decl Declaration already has the target 630/// attribute. 631static bool 632DeclHasAttr(const Decl *decl, const Attr *target) { 633 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 634 if (attr->getKind() == target->getKind()) 635 return true; 636 637 return false; 638} 639 640/// MergeAttributes - append attributes from the Old decl to the New one. 641static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 642 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 643 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 644 Attr *NewAttr = attr->clone(C); 645 NewAttr->setInherited(true); 646 New->addAttr(NewAttr); 647 } 648 } 649} 650 651/// Used in MergeFunctionDecl to keep track of function parameters in 652/// C. 653struct GNUCompatibleParamWarning { 654 ParmVarDecl *OldParm; 655 ParmVarDecl *NewParm; 656 QualType PromotedType; 657}; 658 659/// MergeFunctionDecl - We just parsed a function 'New' from 660/// declarator D which has the same name and scope as a previous 661/// declaration 'Old'. Figure out how to resolve this situation, 662/// merging decls or emitting diagnostics as appropriate. 663/// 664/// In C++, New and Old must be declarations that are not 665/// overloaded. Use IsOverload to determine whether New and Old are 666/// overloaded, and to select the Old declaration that New should be 667/// merged with. 668/// 669/// Returns true if there was an error, false otherwise. 670bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 671 assert(!isa<OverloadedFunctionDecl>(OldD) && 672 "Cannot merge with an overloaded function declaration"); 673 674 // Verify the old decl was also a function. 675 FunctionDecl *Old = 0; 676 if (FunctionTemplateDecl *OldFunctionTemplate 677 = dyn_cast<FunctionTemplateDecl>(OldD)) 678 Old = OldFunctionTemplate->getTemplatedDecl(); 679 else 680 Old = dyn_cast<FunctionDecl>(OldD); 681 if (!Old) { 682 Diag(New->getLocation(), diag::err_redefinition_different_kind) 683 << New->getDeclName(); 684 Diag(OldD->getLocation(), diag::note_previous_definition); 685 return true; 686 } 687 688 // Determine whether the previous declaration was a definition, 689 // implicit declaration, or a declaration. 690 diag::kind PrevDiag; 691 if (Old->isThisDeclarationADefinition()) 692 PrevDiag = diag::note_previous_definition; 693 else if (Old->isImplicit()) 694 PrevDiag = diag::note_previous_implicit_declaration; 695 else 696 PrevDiag = diag::note_previous_declaration; 697 698 QualType OldQType = Context.getCanonicalType(Old->getType()); 699 QualType NewQType = Context.getCanonicalType(New->getType()); 700 701 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 702 New->getStorageClass() == FunctionDecl::Static && 703 Old->getStorageClass() != FunctionDecl::Static) { 704 Diag(New->getLocation(), diag::err_static_non_static) 705 << New; 706 Diag(Old->getLocation(), PrevDiag); 707 return true; 708 } 709 710 if (getLangOptions().CPlusPlus) { 711 // (C++98 13.1p2): 712 // Certain function declarations cannot be overloaded: 713 // -- Function declarations that differ only in the return type 714 // cannot be overloaded. 715 QualType OldReturnType 716 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 717 QualType NewReturnType 718 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 719 if (OldReturnType != NewReturnType) { 720 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 721 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 722 return true; 723 } 724 725 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 726 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 727 if (OldMethod && NewMethod && 728 NewMethod->getLexicalDeclContext()->isRecord()) { 729 // -- Member function declarations with the same name and the 730 // same parameter types cannot be overloaded if any of them 731 // is a static member function declaration. 732 if (OldMethod->isStatic() || NewMethod->isStatic()) { 733 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 734 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 735 return true; 736 } 737 738 // C++ [class.mem]p1: 739 // [...] A member shall not be declared twice in the 740 // member-specification, except that a nested class or member 741 // class template can be declared and then later defined. 742 unsigned NewDiag; 743 if (isa<CXXConstructorDecl>(OldMethod)) 744 NewDiag = diag::err_constructor_redeclared; 745 else if (isa<CXXDestructorDecl>(NewMethod)) 746 NewDiag = diag::err_destructor_redeclared; 747 else if (isa<CXXConversionDecl>(NewMethod)) 748 NewDiag = diag::err_conv_function_redeclared; 749 else 750 NewDiag = diag::err_member_redeclared; 751 752 Diag(New->getLocation(), NewDiag); 753 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 754 } 755 756 // (C++98 8.3.5p3): 757 // All declarations for a function shall agree exactly in both the 758 // return type and the parameter-type-list. 759 if (OldQType == NewQType) 760 return MergeCompatibleFunctionDecls(New, Old); 761 762 // Fall through for conflicting redeclarations and redefinitions. 763 } 764 765 // C: Function types need to be compatible, not identical. This handles 766 // duplicate function decls like "void f(int); void f(enum X);" properly. 767 if (!getLangOptions().CPlusPlus && 768 Context.typesAreCompatible(OldQType, NewQType)) { 769 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 770 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 771 const FunctionProtoType *OldProto = 0; 772 if (isa<FunctionNoProtoType>(NewFuncType) && 773 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 774 // The old declaration provided a function prototype, but the 775 // new declaration does not. Merge in the prototype. 776 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 777 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 778 OldProto->arg_type_end()); 779 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 780 ParamTypes.data(), ParamTypes.size(), 781 OldProto->isVariadic(), 782 OldProto->getTypeQuals()); 783 New->setType(NewQType); 784 New->setHasInheritedPrototype(); 785 786 // Synthesize a parameter for each argument type. 787 llvm::SmallVector<ParmVarDecl*, 16> Params; 788 for (FunctionProtoType::arg_type_iterator 789 ParamType = OldProto->arg_type_begin(), 790 ParamEnd = OldProto->arg_type_end(); 791 ParamType != ParamEnd; ++ParamType) { 792 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 793 SourceLocation(), 0, 794 *ParamType, /*DInfo=*/0, 795 VarDecl::None, 0); 796 Param->setImplicit(); 797 Params.push_back(Param); 798 } 799 800 New->setParams(Context, Params.data(), Params.size()); 801 } 802 803 return MergeCompatibleFunctionDecls(New, Old); 804 } 805 806 // GNU C permits a K&R definition to follow a prototype declaration 807 // if the declared types of the parameters in the K&R definition 808 // match the types in the prototype declaration, even when the 809 // promoted types of the parameters from the K&R definition differ 810 // from the types in the prototype. GCC then keeps the types from 811 // the prototype. 812 // 813 // If a variadic prototype is followed by a non-variadic K&R definition, 814 // the K&R definition becomes variadic. This is sort of an edge case, but 815 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 816 // C99 6.9.1p8. 817 if (!getLangOptions().CPlusPlus && 818 Old->hasPrototype() && !New->hasPrototype() && 819 New->getType()->getAsFunctionProtoType() && 820 Old->getNumParams() == New->getNumParams()) { 821 llvm::SmallVector<QualType, 16> ArgTypes; 822 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 823 const FunctionProtoType *OldProto 824 = Old->getType()->getAsFunctionProtoType(); 825 const FunctionProtoType *NewProto 826 = New->getType()->getAsFunctionProtoType(); 827 828 // Determine whether this is the GNU C extension. 829 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 830 NewProto->getResultType()); 831 bool LooseCompatible = !MergedReturn.isNull(); 832 for (unsigned Idx = 0, End = Old->getNumParams(); 833 LooseCompatible && Idx != End; ++Idx) { 834 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 835 ParmVarDecl *NewParm = New->getParamDecl(Idx); 836 if (Context.typesAreCompatible(OldParm->getType(), 837 NewProto->getArgType(Idx))) { 838 ArgTypes.push_back(NewParm->getType()); 839 } else if (Context.typesAreCompatible(OldParm->getType(), 840 NewParm->getType())) { 841 GNUCompatibleParamWarning Warn 842 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 843 Warnings.push_back(Warn); 844 ArgTypes.push_back(NewParm->getType()); 845 } else 846 LooseCompatible = false; 847 } 848 849 if (LooseCompatible) { 850 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 851 Diag(Warnings[Warn].NewParm->getLocation(), 852 diag::ext_param_promoted_not_compatible_with_prototype) 853 << Warnings[Warn].PromotedType 854 << Warnings[Warn].OldParm->getType(); 855 Diag(Warnings[Warn].OldParm->getLocation(), 856 diag::note_previous_declaration); 857 } 858 859 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 860 ArgTypes.size(), 861 OldProto->isVariadic(), 0)); 862 return MergeCompatibleFunctionDecls(New, Old); 863 } 864 865 // Fall through to diagnose conflicting types. 866 } 867 868 // A function that has already been declared has been redeclared or defined 869 // with a different type- show appropriate diagnostic 870 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 871 // The user has declared a builtin function with an incompatible 872 // signature. 873 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 874 // The function the user is redeclaring is a library-defined 875 // function like 'malloc' or 'printf'. Warn about the 876 // redeclaration, then pretend that we don't know about this 877 // library built-in. 878 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 879 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 880 << Old << Old->getType(); 881 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 882 Old->setInvalidDecl(); 883 return false; 884 } 885 886 PrevDiag = diag::note_previous_builtin_declaration; 887 } 888 889 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 890 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 891 return true; 892} 893 894/// \brief Completes the merge of two function declarations that are 895/// known to be compatible. 896/// 897/// This routine handles the merging of attributes and other 898/// properties of function declarations form the old declaration to 899/// the new declaration, once we know that New is in fact a 900/// redeclaration of Old. 901/// 902/// \returns false 903bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 904 // Merge the attributes 905 MergeAttributes(New, Old, Context); 906 907 // Merge the storage class. 908 if (Old->getStorageClass() != FunctionDecl::Extern) 909 New->setStorageClass(Old->getStorageClass()); 910 911 // Merge "inline" 912 if (Old->isInline()) 913 New->setInline(true); 914 915 // If this function declaration by itself qualifies as a C99 inline 916 // definition (C99 6.7.4p6), but the previous definition did not, 917 // then the function is not a C99 inline definition. 918 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 919 New->setC99InlineDefinition(false); 920 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 921 // Mark all preceding definitions as not being C99 inline definitions. 922 for (const FunctionDecl *Prev = Old; Prev; 923 Prev = Prev->getPreviousDeclaration()) 924 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 925 } 926 927 // Merge "pure" flag. 928 if (Old->isPure()) 929 New->setPure(); 930 931 // Merge the "deleted" flag. 932 if (Old->isDeleted()) 933 New->setDeleted(); 934 935 if (getLangOptions().CPlusPlus) 936 return MergeCXXFunctionDecl(New, Old); 937 938 return false; 939} 940 941/// MergeVarDecl - We just parsed a variable 'New' which has the same name 942/// and scope as a previous declaration 'Old'. Figure out how to resolve this 943/// situation, merging decls or emitting diagnostics as appropriate. 944/// 945/// Tentative definition rules (C99 6.9.2p2) are checked by 946/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 947/// definitions here, since the initializer hasn't been attached. 948/// 949void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 950 // If either decl is invalid, make sure the new one is marked invalid and 951 // don't do any other checking. 952 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 953 return New->setInvalidDecl(); 954 955 // Verify the old decl was also a variable. 956 VarDecl *Old = dyn_cast<VarDecl>(OldD); 957 if (!Old) { 958 Diag(New->getLocation(), diag::err_redefinition_different_kind) 959 << New->getDeclName(); 960 Diag(OldD->getLocation(), diag::note_previous_definition); 961 return New->setInvalidDecl(); 962 } 963 964 MergeAttributes(New, Old, Context); 965 966 // Merge the types 967 QualType MergedT; 968 if (getLangOptions().CPlusPlus) { 969 if (Context.hasSameType(New->getType(), Old->getType())) 970 MergedT = New->getType(); 971 } else { 972 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 973 } 974 if (MergedT.isNull()) { 975 Diag(New->getLocation(), diag::err_redefinition_different_type) 976 << New->getDeclName(); 977 Diag(Old->getLocation(), diag::note_previous_definition); 978 return New->setInvalidDecl(); 979 } 980 New->setType(MergedT); 981 982 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 983 if (New->getStorageClass() == VarDecl::Static && 984 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 985 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 986 Diag(Old->getLocation(), diag::note_previous_definition); 987 return New->setInvalidDecl(); 988 } 989 // C99 6.2.2p4: 990 // For an identifier declared with the storage-class specifier 991 // extern in a scope in which a prior declaration of that 992 // identifier is visible,23) if the prior declaration specifies 993 // internal or external linkage, the linkage of the identifier at 994 // the later declaration is the same as the linkage specified at 995 // the prior declaration. If no prior declaration is visible, or 996 // if the prior declaration specifies no linkage, then the 997 // identifier has external linkage. 998 if (New->hasExternalStorage() && Old->hasLinkage()) 999 /* Okay */; 1000 else if (New->getStorageClass() != VarDecl::Static && 1001 Old->getStorageClass() == VarDecl::Static) { 1002 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1003 Diag(Old->getLocation(), diag::note_previous_definition); 1004 return New->setInvalidDecl(); 1005 } 1006 1007 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1008 1009 // FIXME: The test for external storage here seems wrong? We still 1010 // need to check for mismatches. 1011 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1012 // Don't complain about out-of-line definitions of static members. 1013 !(Old->getLexicalDeclContext()->isRecord() && 1014 !New->getLexicalDeclContext()->isRecord())) { 1015 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1016 Diag(Old->getLocation(), diag::note_previous_definition); 1017 return New->setInvalidDecl(); 1018 } 1019 1020 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1021 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1022 Diag(Old->getLocation(), diag::note_previous_definition); 1023 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1024 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1025 Diag(Old->getLocation(), diag::note_previous_definition); 1026 } 1027 1028 // Keep a chain of previous declarations. 1029 New->setPreviousDeclaration(Old); 1030} 1031 1032/// CheckFallThrough - Check that we don't fall off the end of a 1033/// Statement that should return a value. 1034/// 1035/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1036/// MaybeFallThrough iff we might or might not fall off the end and 1037/// NeverFallThrough iff we never fall off the end of the statement. We assume 1038/// that functions not marked noreturn will return. 1039Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1040 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1041 1042 // FIXME: They should never return 0, fix that, delete this code. 1043 if (cfg == 0) 1044 return NeverFallThrough; 1045 // The CFG leaves in dead things, and we don't want to dead code paths to 1046 // confuse us, so we mark all live things first. 1047 std::queue<CFGBlock*> workq; 1048 llvm::BitVector live(cfg->getNumBlockIDs()); 1049 // Prep work queue 1050 workq.push(&cfg->getEntry()); 1051 // Solve 1052 while (!workq.empty()) { 1053 CFGBlock *item = workq.front(); 1054 workq.pop(); 1055 live.set(item->getBlockID()); 1056 for (CFGBlock::succ_iterator I=item->succ_begin(), 1057 E=item->succ_end(); 1058 I != E; 1059 ++I) { 1060 if ((*I) && !live[(*I)->getBlockID()]) { 1061 live.set((*I)->getBlockID()); 1062 workq.push(*I); 1063 } 1064 } 1065 } 1066 1067 // Now we know what is live, we check the live precessors of the exit block 1068 // and look for fall through paths, being careful to ignore normal returns, 1069 // and exceptional paths. 1070 bool HasLiveReturn = false; 1071 bool HasFakeEdge = false; 1072 bool HasPlainEdge = false; 1073 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1074 E = cfg->getExit().pred_end(); 1075 I != E; 1076 ++I) { 1077 CFGBlock& B = **I; 1078 if (!live[B.getBlockID()]) 1079 continue; 1080 if (B.size() == 0) { 1081 // A labeled empty statement, or the entry block... 1082 HasPlainEdge = true; 1083 continue; 1084 } 1085 Stmt *S = B[B.size()-1]; 1086 if (isa<ReturnStmt>(S)) { 1087 HasLiveReturn = true; 1088 continue; 1089 } 1090 if (isa<ObjCAtThrowStmt>(S)) { 1091 HasFakeEdge = true; 1092 continue; 1093 } 1094 if (isa<CXXThrowExpr>(S)) { 1095 HasFakeEdge = true; 1096 continue; 1097 } 1098 bool NoReturnEdge = false; 1099 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1100 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1101 if (CEE->getType().getNoReturnAttr()) { 1102 NoReturnEdge = true; 1103 HasFakeEdge = true; 1104 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1105 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1106 if (FD->hasAttr<NoReturnAttr>()) { 1107 NoReturnEdge = true; 1108 HasFakeEdge = true; 1109 } 1110 } 1111 } 1112 } 1113 // FIXME: Add noreturn message sends. 1114 if (NoReturnEdge == false) 1115 HasPlainEdge = true; 1116 } 1117 if (!HasPlainEdge) 1118 return NeverFallThrough; 1119 if (HasFakeEdge || HasLiveReturn) 1120 return MaybeFallThrough; 1121 // This says AlwaysFallThrough for calls to functions that are not marked 1122 // noreturn, that don't return. If people would like this warning to be more 1123 // accurate, such functions should be marked as noreturn. 1124 return AlwaysFallThrough; 1125} 1126 1127/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1128/// function that should return a value. Check that we don't fall off the end 1129/// of a noreturn function. We assume that functions and blocks not marked 1130/// noreturn will return. 1131void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1132 // FIXME: Would be nice if we had a better way to control cascading errors, 1133 // but for now, avoid them. The problem is that when Parse sees: 1134 // int foo() { return a; } 1135 // The return is eaten and the Sema code sees just: 1136 // int foo() { } 1137 // which this code would then warn about. 1138 if (getDiagnostics().hasErrorOccurred()) 1139 return; 1140 bool ReturnsVoid = false; 1141 bool HasNoReturn = false; 1142 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1143 if (FD->getResultType()->isVoidType()) 1144 ReturnsVoid = true; 1145 if (FD->hasAttr<NoReturnAttr>()) 1146 HasNoReturn = true; 1147 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1148 if (MD->getResultType()->isVoidType()) 1149 ReturnsVoid = true; 1150 if (MD->hasAttr<NoReturnAttr>()) 1151 HasNoReturn = true; 1152 } 1153 1154 // Short circuit for compilation speed. 1155 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1156 == Diagnostic::Ignored || ReturnsVoid) 1157 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1158 == Diagnostic::Ignored || !HasNoReturn) 1159 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1160 == Diagnostic::Ignored || !ReturnsVoid)) 1161 return; 1162 // FIXME: Funtion try block 1163 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1164 switch (CheckFallThrough(Body)) { 1165 case MaybeFallThrough: 1166 if (HasNoReturn) 1167 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1168 else if (!ReturnsVoid) 1169 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1170 break; 1171 case AlwaysFallThrough: 1172 if (HasNoReturn) 1173 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1174 else if (!ReturnsVoid) 1175 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1176 break; 1177 case NeverFallThrough: 1178 if (ReturnsVoid) 1179 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1180 break; 1181 } 1182 } 1183} 1184 1185/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1186/// that should return a value. Check that we don't fall off the end of a 1187/// noreturn block. We assume that functions and blocks not marked noreturn 1188/// will return. 1189void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1190 // FIXME: Would be nice if we had a better way to control cascading errors, 1191 // but for now, avoid them. The problem is that when Parse sees: 1192 // int foo() { return a; } 1193 // The return is eaten and the Sema code sees just: 1194 // int foo() { } 1195 // which this code would then warn about. 1196 if (getDiagnostics().hasErrorOccurred()) 1197 return; 1198 bool ReturnsVoid = false; 1199 bool HasNoReturn = false; 1200 if (const FunctionType *FT = BlockTy->getPointeeType()->getAsFunctionType()) { 1201 if (FT->getResultType()->isVoidType()) 1202 ReturnsVoid = true; 1203 if (FT->getNoReturnAttr()) 1204 HasNoReturn = true; 1205 } 1206 1207 // Short circuit for compilation speed. 1208 if (ReturnsVoid 1209 && !HasNoReturn 1210 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1211 == Diagnostic::Ignored || !ReturnsVoid)) 1212 return; 1213 // FIXME: Funtion try block 1214 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1215 switch (CheckFallThrough(Body)) { 1216 case MaybeFallThrough: 1217 if (HasNoReturn) 1218 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1219 else if (!ReturnsVoid) 1220 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1221 break; 1222 case AlwaysFallThrough: 1223 if (HasNoReturn) 1224 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1225 else if (!ReturnsVoid) 1226 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1227 break; 1228 case NeverFallThrough: 1229 if (ReturnsVoid) 1230 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1231 break; 1232 } 1233 } 1234} 1235 1236/// CheckParmsForFunctionDef - Check that the parameters of the given 1237/// function are appropriate for the definition of a function. This 1238/// takes care of any checks that cannot be performed on the 1239/// declaration itself, e.g., that the types of each of the function 1240/// parameters are complete. 1241bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1242 bool HasInvalidParm = false; 1243 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1244 ParmVarDecl *Param = FD->getParamDecl(p); 1245 1246 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1247 // function declarator that is part of a function definition of 1248 // that function shall not have incomplete type. 1249 // 1250 // This is also C++ [dcl.fct]p6. 1251 if (!Param->isInvalidDecl() && 1252 RequireCompleteType(Param->getLocation(), Param->getType(), 1253 diag::err_typecheck_decl_incomplete_type)) { 1254 Param->setInvalidDecl(); 1255 HasInvalidParm = true; 1256 } 1257 1258 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1259 // declaration of each parameter shall include an identifier. 1260 if (Param->getIdentifier() == 0 && 1261 !Param->isImplicit() && 1262 !getLangOptions().CPlusPlus) 1263 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1264 } 1265 1266 return HasInvalidParm; 1267} 1268 1269/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1270/// no declarator (e.g. "struct foo;") is parsed. 1271Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1272 // FIXME: Error on auto/register at file scope 1273 // FIXME: Error on inline/virtual/explicit 1274 // FIXME: Error on invalid restrict 1275 // FIXME: Warn on useless __thread 1276 // FIXME: Warn on useless const/volatile 1277 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1278 // FIXME: Warn on useless attributes 1279 TagDecl *Tag = 0; 1280 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1281 DS.getTypeSpecType() == DeclSpec::TST_struct || 1282 DS.getTypeSpecType() == DeclSpec::TST_union || 1283 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1284 if (!DS.getTypeRep()) // We probably had an error 1285 return DeclPtrTy(); 1286 1287 // Note that the above type specs guarantee that the 1288 // type rep is a Decl, whereas in many of the others 1289 // it's a Type. 1290 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1291 } 1292 1293 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1294 if (!Record->getDeclName() && Record->isDefinition() && 1295 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1296 if (getLangOptions().CPlusPlus || 1297 Record->getDeclContext()->isRecord()) 1298 return BuildAnonymousStructOrUnion(S, DS, Record); 1299 1300 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1301 << DS.getSourceRange(); 1302 } 1303 1304 // Microsoft allows unnamed struct/union fields. Don't complain 1305 // about them. 1306 // FIXME: Should we support Microsoft's extensions in this area? 1307 if (Record->getDeclName() && getLangOptions().Microsoft) 1308 return DeclPtrTy::make(Tag); 1309 } 1310 1311 if (!DS.isMissingDeclaratorOk() && 1312 DS.getTypeSpecType() != DeclSpec::TST_error) { 1313 // Warn about typedefs of enums without names, since this is an 1314 // extension in both Microsoft an GNU. 1315 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1316 Tag && isa<EnumDecl>(Tag)) { 1317 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1318 << DS.getSourceRange(); 1319 return DeclPtrTy::make(Tag); 1320 } 1321 1322 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1323 << DS.getSourceRange(); 1324 return DeclPtrTy(); 1325 } 1326 1327 return DeclPtrTy::make(Tag); 1328} 1329 1330/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1331/// anonymous struct or union AnonRecord into the owning context Owner 1332/// and scope S. This routine will be invoked just after we realize 1333/// that an unnamed union or struct is actually an anonymous union or 1334/// struct, e.g., 1335/// 1336/// @code 1337/// union { 1338/// int i; 1339/// float f; 1340/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1341/// // f into the surrounding scope.x 1342/// @endcode 1343/// 1344/// This routine is recursive, injecting the names of nested anonymous 1345/// structs/unions into the owning context and scope as well. 1346bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1347 RecordDecl *AnonRecord) { 1348 bool Invalid = false; 1349 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1350 FEnd = AnonRecord->field_end(); 1351 F != FEnd; ++F) { 1352 if ((*F)->getDeclName()) { 1353 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1354 LookupOrdinaryName, true); 1355 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1356 // C++ [class.union]p2: 1357 // The names of the members of an anonymous union shall be 1358 // distinct from the names of any other entity in the 1359 // scope in which the anonymous union is declared. 1360 unsigned diagKind 1361 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1362 : diag::err_anonymous_struct_member_redecl; 1363 Diag((*F)->getLocation(), diagKind) 1364 << (*F)->getDeclName(); 1365 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1366 Invalid = true; 1367 } else { 1368 // C++ [class.union]p2: 1369 // For the purpose of name lookup, after the anonymous union 1370 // definition, the members of the anonymous union are 1371 // considered to have been defined in the scope in which the 1372 // anonymous union is declared. 1373 Owner->makeDeclVisibleInContext(*F); 1374 S->AddDecl(DeclPtrTy::make(*F)); 1375 IdResolver.AddDecl(*F); 1376 } 1377 } else if (const RecordType *InnerRecordType 1378 = (*F)->getType()->getAs<RecordType>()) { 1379 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1380 if (InnerRecord->isAnonymousStructOrUnion()) 1381 Invalid = Invalid || 1382 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1383 } 1384 } 1385 1386 return Invalid; 1387} 1388 1389/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1390/// anonymous structure or union. Anonymous unions are a C++ feature 1391/// (C++ [class.union]) and a GNU C extension; anonymous structures 1392/// are a GNU C and GNU C++ extension. 1393Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1394 RecordDecl *Record) { 1395 DeclContext *Owner = Record->getDeclContext(); 1396 1397 // Diagnose whether this anonymous struct/union is an extension. 1398 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1399 Diag(Record->getLocation(), diag::ext_anonymous_union); 1400 else if (!Record->isUnion()) 1401 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1402 1403 // C and C++ require different kinds of checks for anonymous 1404 // structs/unions. 1405 bool Invalid = false; 1406 if (getLangOptions().CPlusPlus) { 1407 const char* PrevSpec = 0; 1408 unsigned DiagID; 1409 // C++ [class.union]p3: 1410 // Anonymous unions declared in a named namespace or in the 1411 // global namespace shall be declared static. 1412 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1413 (isa<TranslationUnitDecl>(Owner) || 1414 (isa<NamespaceDecl>(Owner) && 1415 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1416 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1417 Invalid = true; 1418 1419 // Recover by adding 'static'. 1420 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1421 PrevSpec, DiagID); 1422 } 1423 // C++ [class.union]p3: 1424 // A storage class is not allowed in a declaration of an 1425 // anonymous union in a class scope. 1426 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1427 isa<RecordDecl>(Owner)) { 1428 Diag(DS.getStorageClassSpecLoc(), 1429 diag::err_anonymous_union_with_storage_spec); 1430 Invalid = true; 1431 1432 // Recover by removing the storage specifier. 1433 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1434 PrevSpec, DiagID); 1435 } 1436 1437 // C++ [class.union]p2: 1438 // The member-specification of an anonymous union shall only 1439 // define non-static data members. [Note: nested types and 1440 // functions cannot be declared within an anonymous union. ] 1441 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1442 MemEnd = Record->decls_end(); 1443 Mem != MemEnd; ++Mem) { 1444 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1445 // C++ [class.union]p3: 1446 // An anonymous union shall not have private or protected 1447 // members (clause 11). 1448 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1449 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1450 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1451 Invalid = true; 1452 } 1453 } else if ((*Mem)->isImplicit()) { 1454 // Any implicit members are fine. 1455 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1456 // This is a type that showed up in an 1457 // elaborated-type-specifier inside the anonymous struct or 1458 // union, but which actually declares a type outside of the 1459 // anonymous struct or union. It's okay. 1460 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1461 if (!MemRecord->isAnonymousStructOrUnion() && 1462 MemRecord->getDeclName()) { 1463 // This is a nested type declaration. 1464 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1465 << (int)Record->isUnion(); 1466 Invalid = true; 1467 } 1468 } else { 1469 // We have something that isn't a non-static data 1470 // member. Complain about it. 1471 unsigned DK = diag::err_anonymous_record_bad_member; 1472 if (isa<TypeDecl>(*Mem)) 1473 DK = diag::err_anonymous_record_with_type; 1474 else if (isa<FunctionDecl>(*Mem)) 1475 DK = diag::err_anonymous_record_with_function; 1476 else if (isa<VarDecl>(*Mem)) 1477 DK = diag::err_anonymous_record_with_static; 1478 Diag((*Mem)->getLocation(), DK) 1479 << (int)Record->isUnion(); 1480 Invalid = true; 1481 } 1482 } 1483 } 1484 1485 if (!Record->isUnion() && !Owner->isRecord()) { 1486 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1487 << (int)getLangOptions().CPlusPlus; 1488 Invalid = true; 1489 } 1490 1491 // Create a declaration for this anonymous struct/union. 1492 NamedDecl *Anon = 0; 1493 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1494 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1495 /*IdentifierInfo=*/0, 1496 Context.getTypeDeclType(Record), 1497 // FIXME: Type source info. 1498 /*DInfo=*/0, 1499 /*BitWidth=*/0, /*Mutable=*/false); 1500 Anon->setAccess(AS_public); 1501 if (getLangOptions().CPlusPlus) 1502 FieldCollector->Add(cast<FieldDecl>(Anon)); 1503 } else { 1504 VarDecl::StorageClass SC; 1505 switch (DS.getStorageClassSpec()) { 1506 default: assert(0 && "Unknown storage class!"); 1507 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1508 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1509 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1510 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1511 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1512 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1513 case DeclSpec::SCS_mutable: 1514 // mutable can only appear on non-static class members, so it's always 1515 // an error here 1516 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1517 Invalid = true; 1518 SC = VarDecl::None; 1519 break; 1520 } 1521 1522 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1523 /*IdentifierInfo=*/0, 1524 Context.getTypeDeclType(Record), 1525 // FIXME: Type source info. 1526 /*DInfo=*/0, 1527 SC); 1528 } 1529 Anon->setImplicit(); 1530 1531 // Add the anonymous struct/union object to the current 1532 // context. We'll be referencing this object when we refer to one of 1533 // its members. 1534 Owner->addDecl(Anon); 1535 1536 // Inject the members of the anonymous struct/union into the owning 1537 // context and into the identifier resolver chain for name lookup 1538 // purposes. 1539 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1540 Invalid = true; 1541 1542 // Mark this as an anonymous struct/union type. Note that we do not 1543 // do this until after we have already checked and injected the 1544 // members of this anonymous struct/union type, because otherwise 1545 // the members could be injected twice: once by DeclContext when it 1546 // builds its lookup table, and once by 1547 // InjectAnonymousStructOrUnionMembers. 1548 Record->setAnonymousStructOrUnion(true); 1549 1550 if (Invalid) 1551 Anon->setInvalidDecl(); 1552 1553 return DeclPtrTy::make(Anon); 1554} 1555 1556 1557/// GetNameForDeclarator - Determine the full declaration name for the 1558/// given Declarator. 1559DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1560 switch (D.getKind()) { 1561 case Declarator::DK_Abstract: 1562 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1563 return DeclarationName(); 1564 1565 case Declarator::DK_Normal: 1566 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1567 return DeclarationName(D.getIdentifier()); 1568 1569 case Declarator::DK_Constructor: { 1570 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1571 return Context.DeclarationNames.getCXXConstructorName( 1572 Context.getCanonicalType(Ty)); 1573 } 1574 1575 case Declarator::DK_Destructor: { 1576 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1577 return Context.DeclarationNames.getCXXDestructorName( 1578 Context.getCanonicalType(Ty)); 1579 } 1580 1581 case Declarator::DK_Conversion: { 1582 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1583 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1584 return Context.DeclarationNames.getCXXConversionFunctionName( 1585 Context.getCanonicalType(Ty)); 1586 } 1587 1588 case Declarator::DK_Operator: 1589 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1590 return Context.DeclarationNames.getCXXOperatorName( 1591 D.getOverloadedOperator()); 1592 } 1593 1594 assert(false && "Unknown name kind"); 1595 return DeclarationName(); 1596} 1597 1598/// isNearlyMatchingFunction - Determine whether the C++ functions 1599/// Declaration and Definition are "nearly" matching. This heuristic 1600/// is used to improve diagnostics in the case where an out-of-line 1601/// function definition doesn't match any declaration within 1602/// the class or namespace. 1603static bool isNearlyMatchingFunction(ASTContext &Context, 1604 FunctionDecl *Declaration, 1605 FunctionDecl *Definition) { 1606 if (Declaration->param_size() != Definition->param_size()) 1607 return false; 1608 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1609 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1610 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1611 1612 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1613 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1614 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1615 return false; 1616 } 1617 1618 return true; 1619} 1620 1621Sema::DeclPtrTy 1622Sema::HandleDeclarator(Scope *S, Declarator &D, 1623 MultiTemplateParamsArg TemplateParamLists, 1624 bool IsFunctionDefinition) { 1625 DeclarationName Name = GetNameForDeclarator(D); 1626 1627 // All of these full declarators require an identifier. If it doesn't have 1628 // one, the ParsedFreeStandingDeclSpec action should be used. 1629 if (!Name) { 1630 if (!D.isInvalidType()) // Reject this if we think it is valid. 1631 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1632 diag::err_declarator_need_ident) 1633 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1634 return DeclPtrTy(); 1635 } 1636 1637 // The scope passed in may not be a decl scope. Zip up the scope tree until 1638 // we find one that is. 1639 while ((S->getFlags() & Scope::DeclScope) == 0 || 1640 (S->getFlags() & Scope::TemplateParamScope) != 0) 1641 S = S->getParent(); 1642 1643 // If this is an out-of-line definition of a member of a class template 1644 // or class template partial specialization, we may need to rebuild the 1645 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1646 // for more information. 1647 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1648 // handle expressions properly. 1649 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1650 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1651 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1652 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1653 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1654 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1655 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1656 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1657 // FIXME: Preserve type source info. 1658 QualType T = GetTypeFromParser(DS.getTypeRep()); 1659 EnterDeclaratorContext(S, DC); 1660 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1661 ExitDeclaratorContext(S); 1662 if (T.isNull()) 1663 return DeclPtrTy(); 1664 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1665 } 1666 } 1667 1668 DeclContext *DC; 1669 NamedDecl *PrevDecl; 1670 NamedDecl *New; 1671 1672 DeclaratorInfo *DInfo = 0; 1673 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1674 1675 // See if this is a redefinition of a variable in the same scope. 1676 if (D.getCXXScopeSpec().isInvalid()) { 1677 DC = CurContext; 1678 PrevDecl = 0; 1679 D.setInvalidType(); 1680 } else if (!D.getCXXScopeSpec().isSet()) { 1681 LookupNameKind NameKind = LookupOrdinaryName; 1682 1683 // If the declaration we're planning to build will be a function 1684 // or object with linkage, then look for another declaration with 1685 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1686 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1687 /* Do nothing*/; 1688 else if (R->isFunctionType()) { 1689 if (CurContext->isFunctionOrMethod() || 1690 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1691 NameKind = LookupRedeclarationWithLinkage; 1692 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1693 NameKind = LookupRedeclarationWithLinkage; 1694 else if (CurContext->getLookupContext()->isTranslationUnit() && 1695 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1696 NameKind = LookupRedeclarationWithLinkage; 1697 1698 DC = CurContext; 1699 PrevDecl = LookupName(S, Name, NameKind, true, 1700 NameKind == LookupRedeclarationWithLinkage, 1701 D.getIdentifierLoc()); 1702 } else { // Something like "int foo::x;" 1703 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1704 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1705 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1706 1707 // C++ 7.3.1.2p2: 1708 // Members (including explicit specializations of templates) of a named 1709 // namespace can also be defined outside that namespace by explicit 1710 // qualification of the name being defined, provided that the entity being 1711 // defined was already declared in the namespace and the definition appears 1712 // after the point of declaration in a namespace that encloses the 1713 // declarations namespace. 1714 // 1715 // Note that we only check the context at this point. We don't yet 1716 // have enough information to make sure that PrevDecl is actually 1717 // the declaration we want to match. For example, given: 1718 // 1719 // class X { 1720 // void f(); 1721 // void f(float); 1722 // }; 1723 // 1724 // void X::f(int) { } // ill-formed 1725 // 1726 // In this case, PrevDecl will point to the overload set 1727 // containing the two f's declared in X, but neither of them 1728 // matches. 1729 1730 // First check whether we named the global scope. 1731 if (isa<TranslationUnitDecl>(DC)) { 1732 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1733 << Name << D.getCXXScopeSpec().getRange(); 1734 } else if (!CurContext->Encloses(DC)) { 1735 // The qualifying scope doesn't enclose the original declaration. 1736 // Emit diagnostic based on current scope. 1737 SourceLocation L = D.getIdentifierLoc(); 1738 SourceRange R = D.getCXXScopeSpec().getRange(); 1739 if (isa<FunctionDecl>(CurContext)) 1740 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1741 else 1742 Diag(L, diag::err_invalid_declarator_scope) 1743 << Name << cast<NamedDecl>(DC) << R; 1744 D.setInvalidType(); 1745 } 1746 } 1747 1748 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1749 // Maybe we will complain about the shadowed template parameter. 1750 if (!D.isInvalidType()) 1751 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1752 D.setInvalidType(); 1753 1754 // Just pretend that we didn't see the previous declaration. 1755 PrevDecl = 0; 1756 } 1757 1758 // In C++, the previous declaration we find might be a tag type 1759 // (class or enum). In this case, the new declaration will hide the 1760 // tag type. Note that this does does not apply if we're declaring a 1761 // typedef (C++ [dcl.typedef]p4). 1762 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1763 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1764 PrevDecl = 0; 1765 1766 bool Redeclaration = false; 1767 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1768 if (TemplateParamLists.size()) { 1769 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1770 return DeclPtrTy(); 1771 } 1772 1773 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1774 } else if (R->isFunctionType()) { 1775 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1776 move(TemplateParamLists), 1777 IsFunctionDefinition, Redeclaration); 1778 } else { 1779 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1780 move(TemplateParamLists), 1781 Redeclaration); 1782 } 1783 1784 if (New == 0) 1785 return DeclPtrTy(); 1786 1787 // If this has an identifier and is not an invalid redeclaration, 1788 // add it to the scope stack. 1789 if (Name && !(Redeclaration && New->isInvalidDecl())) 1790 PushOnScopeChains(New, S); 1791 1792 return DeclPtrTy::make(New); 1793} 1794 1795/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1796/// types into constant array types in certain situations which would otherwise 1797/// be errors (for GCC compatibility). 1798static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1799 ASTContext &Context, 1800 bool &SizeIsNegative) { 1801 // This method tries to turn a variable array into a constant 1802 // array even when the size isn't an ICE. This is necessary 1803 // for compatibility with code that depends on gcc's buggy 1804 // constant expression folding, like struct {char x[(int)(char*)2];} 1805 SizeIsNegative = false; 1806 1807 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1808 QualType Pointee = PTy->getPointeeType(); 1809 QualType FixedType = 1810 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1811 if (FixedType.isNull()) return FixedType; 1812 FixedType = Context.getPointerType(FixedType); 1813 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1814 return FixedType; 1815 } 1816 1817 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1818 if (!VLATy) 1819 return QualType(); 1820 // FIXME: We should probably handle this case 1821 if (VLATy->getElementType()->isVariablyModifiedType()) 1822 return QualType(); 1823 1824 Expr::EvalResult EvalResult; 1825 if (!VLATy->getSizeExpr() || 1826 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1827 !EvalResult.Val.isInt()) 1828 return QualType(); 1829 1830 llvm::APSInt &Res = EvalResult.Val.getInt(); 1831 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1832 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1833 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1834 // so as to transfer ownership to the ConstantArrayWithExpr. 1835 // Alternatively, we could "clone" it (how?). 1836 // Since we don't know how to do things above, we just use the 1837 // very same Expr*. 1838 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1839 Res, ArySizeExpr, 1840 ArrayType::Normal, 0, 1841 VLATy->getBracketsRange()); 1842 } 1843 1844 SizeIsNegative = true; 1845 return QualType(); 1846} 1847 1848/// \brief Register the given locally-scoped external C declaration so 1849/// that it can be found later for redeclarations 1850void 1851Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1852 Scope *S) { 1853 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1854 "Decl is not a locally-scoped decl!"); 1855 // Note that we have a locally-scoped external with this name. 1856 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1857 1858 if (!PrevDecl) 1859 return; 1860 1861 // If there was a previous declaration of this variable, it may be 1862 // in our identifier chain. Update the identifier chain with the new 1863 // declaration. 1864 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1865 // The previous declaration was found on the identifer resolver 1866 // chain, so remove it from its scope. 1867 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1868 S = S->getParent(); 1869 1870 if (S) 1871 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1872 } 1873} 1874 1875/// \brief Diagnose function specifiers on a declaration of an identifier that 1876/// does not identify a function. 1877void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1878 // FIXME: We should probably indicate the identifier in question to avoid 1879 // confusion for constructs like "inline int a(), b;" 1880 if (D.getDeclSpec().isInlineSpecified()) 1881 Diag(D.getDeclSpec().getInlineSpecLoc(), 1882 diag::err_inline_non_function); 1883 1884 if (D.getDeclSpec().isVirtualSpecified()) 1885 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1886 diag::err_virtual_non_function); 1887 1888 if (D.getDeclSpec().isExplicitSpecified()) 1889 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1890 diag::err_explicit_non_function); 1891} 1892 1893NamedDecl* 1894Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1895 QualType R, DeclaratorInfo *DInfo, 1896 Decl* PrevDecl, bool &Redeclaration) { 1897 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1898 if (D.getCXXScopeSpec().isSet()) { 1899 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1900 << D.getCXXScopeSpec().getRange(); 1901 D.setInvalidType(); 1902 // Pretend we didn't see the scope specifier. 1903 DC = 0; 1904 } 1905 1906 if (getLangOptions().CPlusPlus) { 1907 // Check that there are no default arguments (C++ only). 1908 CheckExtraCXXDefaultArguments(D); 1909 } 1910 1911 DiagnoseFunctionSpecifiers(D); 1912 1913 if (D.getDeclSpec().isThreadSpecified()) 1914 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1915 1916 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1917 if (!NewTD) return 0; 1918 1919 if (D.isInvalidType()) 1920 NewTD->setInvalidDecl(); 1921 1922 // Handle attributes prior to checking for duplicates in MergeVarDecl 1923 ProcessDeclAttributes(S, NewTD, D); 1924 // Merge the decl with the existing one if appropriate. If the decl is 1925 // in an outer scope, it isn't the same thing. 1926 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1927 Redeclaration = true; 1928 MergeTypeDefDecl(NewTD, PrevDecl); 1929 } 1930 1931 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1932 // then it shall have block scope. 1933 QualType T = NewTD->getUnderlyingType(); 1934 if (T->isVariablyModifiedType()) { 1935 CurFunctionNeedsScopeChecking = true; 1936 1937 if (S->getFnParent() == 0) { 1938 bool SizeIsNegative; 1939 QualType FixedTy = 1940 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1941 if (!FixedTy.isNull()) { 1942 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1943 NewTD->setUnderlyingType(FixedTy); 1944 } else { 1945 if (SizeIsNegative) 1946 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1947 else if (T->isVariableArrayType()) 1948 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1949 else 1950 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1951 NewTD->setInvalidDecl(); 1952 } 1953 } 1954 } 1955 1956 // If this is the C FILE type, notify the AST context. 1957 if (IdentifierInfo *II = NewTD->getIdentifier()) 1958 if (!NewTD->isInvalidDecl() && 1959 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1960 if (II->isStr("FILE")) 1961 Context.setFILEDecl(NewTD); 1962 else if (II->isStr("jmp_buf")) 1963 Context.setjmp_bufDecl(NewTD); 1964 else if (II->isStr("sigjmp_buf")) 1965 Context.setsigjmp_bufDecl(NewTD); 1966 } 1967 1968 return NewTD; 1969} 1970 1971/// \brief Determines whether the given declaration is an out-of-scope 1972/// previous declaration. 1973/// 1974/// This routine should be invoked when name lookup has found a 1975/// previous declaration (PrevDecl) that is not in the scope where a 1976/// new declaration by the same name is being introduced. If the new 1977/// declaration occurs in a local scope, previous declarations with 1978/// linkage may still be considered previous declarations (C99 1979/// 6.2.2p4-5, C++ [basic.link]p6). 1980/// 1981/// \param PrevDecl the previous declaration found by name 1982/// lookup 1983/// 1984/// \param DC the context in which the new declaration is being 1985/// declared. 1986/// 1987/// \returns true if PrevDecl is an out-of-scope previous declaration 1988/// for a new delcaration with the same name. 1989static bool 1990isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1991 ASTContext &Context) { 1992 if (!PrevDecl) 1993 return 0; 1994 1995 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1996 // case we need to check each of the overloaded functions. 1997 if (!PrevDecl->hasLinkage()) 1998 return false; 1999 2000 if (Context.getLangOptions().CPlusPlus) { 2001 // C++ [basic.link]p6: 2002 // If there is a visible declaration of an entity with linkage 2003 // having the same name and type, ignoring entities declared 2004 // outside the innermost enclosing namespace scope, the block 2005 // scope declaration declares that same entity and receives the 2006 // linkage of the previous declaration. 2007 DeclContext *OuterContext = DC->getLookupContext(); 2008 if (!OuterContext->isFunctionOrMethod()) 2009 // This rule only applies to block-scope declarations. 2010 return false; 2011 else { 2012 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2013 if (PrevOuterContext->isRecord()) 2014 // We found a member function: ignore it. 2015 return false; 2016 else { 2017 // Find the innermost enclosing namespace for the new and 2018 // previous declarations. 2019 while (!OuterContext->isFileContext()) 2020 OuterContext = OuterContext->getParent(); 2021 while (!PrevOuterContext->isFileContext()) 2022 PrevOuterContext = PrevOuterContext->getParent(); 2023 2024 // The previous declaration is in a different namespace, so it 2025 // isn't the same function. 2026 if (OuterContext->getPrimaryContext() != 2027 PrevOuterContext->getPrimaryContext()) 2028 return false; 2029 } 2030 } 2031 } 2032 2033 return true; 2034} 2035 2036NamedDecl* 2037Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2038 QualType R, DeclaratorInfo *DInfo, 2039 NamedDecl* PrevDecl, 2040 MultiTemplateParamsArg TemplateParamLists, 2041 bool &Redeclaration) { 2042 DeclarationName Name = GetNameForDeclarator(D); 2043 2044 // Check that there are no default arguments (C++ only). 2045 if (getLangOptions().CPlusPlus) 2046 CheckExtraCXXDefaultArguments(D); 2047 2048 VarDecl *NewVD; 2049 VarDecl::StorageClass SC; 2050 switch (D.getDeclSpec().getStorageClassSpec()) { 2051 default: assert(0 && "Unknown storage class!"); 2052 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2053 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2054 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2055 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2056 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2057 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2058 case DeclSpec::SCS_mutable: 2059 // mutable can only appear on non-static class members, so it's always 2060 // an error here 2061 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2062 D.setInvalidType(); 2063 SC = VarDecl::None; 2064 break; 2065 } 2066 2067 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2068 if (!II) { 2069 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2070 << Name.getAsString(); 2071 return 0; 2072 } 2073 2074 DiagnoseFunctionSpecifiers(D); 2075 2076 if (!DC->isRecord() && S->getFnParent() == 0) { 2077 // C99 6.9p2: The storage-class specifiers auto and register shall not 2078 // appear in the declaration specifiers in an external declaration. 2079 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2080 2081 // If this is a register variable with an asm label specified, then this 2082 // is a GNU extension. 2083 if (SC == VarDecl::Register && D.getAsmLabel()) 2084 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2085 else 2086 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2087 D.setInvalidType(); 2088 } 2089 } 2090 if (DC->isRecord() && !CurContext->isRecord()) { 2091 // This is an out-of-line definition of a static data member. 2092 if (SC == VarDecl::Static) { 2093 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2094 diag::err_static_out_of_line) 2095 << CodeModificationHint::CreateRemoval( 2096 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2097 } else if (SC == VarDecl::None) 2098 SC = VarDecl::Static; 2099 } 2100 if (SC == VarDecl::Static) { 2101 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2102 if (RD->isLocalClass()) 2103 Diag(D.getIdentifierLoc(), 2104 diag::err_static_data_member_not_allowed_in_local_class) 2105 << Name << RD->getDeclName(); 2106 } 2107 } 2108 2109 // Check that we can declare a template here. 2110 if (TemplateParamLists.size() && 2111 CheckTemplateDeclScope(S, TemplateParamLists)) 2112 return 0; 2113 2114 // Match up the template parameter lists with the scope specifier, then 2115 // determine whether we have a template or a template specialization. 2116 if (TemplateParameterList *TemplateParams 2117 = MatchTemplateParametersToScopeSpecifier( 2118 D.getDeclSpec().getSourceRange().getBegin(), 2119 D.getCXXScopeSpec(), 2120 (TemplateParameterList**)TemplateParamLists.get(), 2121 TemplateParamLists.size())) { 2122 if (TemplateParams->size() > 0) { 2123 // There is no such thing as a variable template. 2124 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2125 << II 2126 << SourceRange(TemplateParams->getTemplateLoc(), 2127 TemplateParams->getRAngleLoc()); 2128 return 0; 2129 } else { 2130 // There is an extraneous 'template<>' for this variable. Complain 2131 // about it, but allow the declaration of the variable. 2132 Diag(TemplateParams->getTemplateLoc(), 2133 diag::err_template_variable_noparams) 2134 << II 2135 << SourceRange(TemplateParams->getTemplateLoc(), 2136 TemplateParams->getRAngleLoc()); 2137 } 2138 } 2139 2140 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2141 II, R, DInfo, SC); 2142 2143 if (D.isInvalidType()) 2144 NewVD->setInvalidDecl(); 2145 2146 if (D.getDeclSpec().isThreadSpecified()) { 2147 if (NewVD->hasLocalStorage()) 2148 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2149 else if (!Context.Target.isTLSSupported()) 2150 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2151 else 2152 NewVD->setThreadSpecified(true); 2153 } 2154 2155 // Set the lexical context. If the declarator has a C++ scope specifier, the 2156 // lexical context will be different from the semantic context. 2157 NewVD->setLexicalDeclContext(CurContext); 2158 2159 // Handle attributes prior to checking for duplicates in MergeVarDecl 2160 ProcessDeclAttributes(S, NewVD, D); 2161 2162 // Handle GNU asm-label extension (encoded as an attribute). 2163 if (Expr *E = (Expr*) D.getAsmLabel()) { 2164 // The parser guarantees this is a string. 2165 StringLiteral *SE = cast<StringLiteral>(E); 2166 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2167 SE->getByteLength()))); 2168 } 2169 2170 // If name lookup finds a previous declaration that is not in the 2171 // same scope as the new declaration, this may still be an 2172 // acceptable redeclaration. 2173 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2174 !(NewVD->hasLinkage() && 2175 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2176 PrevDecl = 0; 2177 2178 // Merge the decl with the existing one if appropriate. 2179 if (PrevDecl) { 2180 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2181 // The user tried to define a non-static data member 2182 // out-of-line (C++ [dcl.meaning]p1). 2183 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2184 << D.getCXXScopeSpec().getRange(); 2185 PrevDecl = 0; 2186 NewVD->setInvalidDecl(); 2187 } 2188 } else if (D.getCXXScopeSpec().isSet()) { 2189 // No previous declaration in the qualifying scope. 2190 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 2191 << Name << D.getCXXScopeSpec().getRange(); 2192 NewVD->setInvalidDecl(); 2193 } 2194 2195 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2196 2197 // attributes declared post-definition are currently ignored 2198 if (PrevDecl) { 2199 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2200 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2201 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2202 Diag(Def->getLocation(), diag::note_previous_definition); 2203 } 2204 } 2205 2206 // If this is a locally-scoped extern C variable, update the map of 2207 // such variables. 2208 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 2209 !NewVD->isInvalidDecl()) 2210 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2211 2212 return NewVD; 2213} 2214 2215/// \brief Perform semantic checking on a newly-created variable 2216/// declaration. 2217/// 2218/// This routine performs all of the type-checking required for a 2219/// variable declaration once it has been built. It is used both to 2220/// check variables after they have been parsed and their declarators 2221/// have been translated into a declaration, and to check variables 2222/// that have been instantiated from a template. 2223/// 2224/// Sets NewVD->isInvalidDecl() if an error was encountered. 2225void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2226 bool &Redeclaration) { 2227 // If the decl is already known invalid, don't check it. 2228 if (NewVD->isInvalidDecl()) 2229 return; 2230 2231 QualType T = NewVD->getType(); 2232 2233 if (T->isObjCInterfaceType()) { 2234 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2235 return NewVD->setInvalidDecl(); 2236 } 2237 2238 // The variable can not have an abstract class type. 2239 if (RequireNonAbstractType(NewVD->getLocation(), T, 2240 diag::err_abstract_type_in_decl, 2241 AbstractVariableType)) 2242 return NewVD->setInvalidDecl(); 2243 2244 // Emit an error if an address space was applied to decl with local storage. 2245 // This includes arrays of objects with address space qualifiers, but not 2246 // automatic variables that point to other address spaces. 2247 // ISO/IEC TR 18037 S5.1.2 2248 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2249 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2250 return NewVD->setInvalidDecl(); 2251 } 2252 2253 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2254 && !NewVD->hasAttr<BlocksAttr>()) 2255 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2256 2257 bool isVM = T->isVariablyModifiedType(); 2258 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2259 NewVD->hasAttr<BlocksAttr>()) 2260 CurFunctionNeedsScopeChecking = true; 2261 2262 if ((isVM && NewVD->hasLinkage()) || 2263 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2264 bool SizeIsNegative; 2265 QualType FixedTy = 2266 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2267 2268 if (FixedTy.isNull() && T->isVariableArrayType()) { 2269 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2270 // FIXME: This won't give the correct result for 2271 // int a[10][n]; 2272 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2273 2274 if (NewVD->isFileVarDecl()) 2275 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2276 << SizeRange; 2277 else if (NewVD->getStorageClass() == VarDecl::Static) 2278 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2279 << SizeRange; 2280 else 2281 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2282 << SizeRange; 2283 return NewVD->setInvalidDecl(); 2284 } 2285 2286 if (FixedTy.isNull()) { 2287 if (NewVD->isFileVarDecl()) 2288 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2289 else 2290 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2291 return NewVD->setInvalidDecl(); 2292 } 2293 2294 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2295 NewVD->setType(FixedTy); 2296 } 2297 2298 if (!PrevDecl && NewVD->isExternC(Context)) { 2299 // Since we did not find anything by this name and we're declaring 2300 // an extern "C" variable, look for a non-visible extern "C" 2301 // declaration with the same name. 2302 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2303 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2304 if (Pos != LocallyScopedExternalDecls.end()) 2305 PrevDecl = Pos->second; 2306 } 2307 2308 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2309 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2310 << T; 2311 return NewVD->setInvalidDecl(); 2312 } 2313 2314 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2315 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2316 return NewVD->setInvalidDecl(); 2317 } 2318 2319 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2320 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2321 return NewVD->setInvalidDecl(); 2322 } 2323 2324 if (PrevDecl) { 2325 Redeclaration = true; 2326 MergeVarDecl(NewVD, PrevDecl); 2327 } 2328} 2329 2330NamedDecl* 2331Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2332 QualType R, DeclaratorInfo *DInfo, 2333 NamedDecl* PrevDecl, 2334 MultiTemplateParamsArg TemplateParamLists, 2335 bool IsFunctionDefinition, bool &Redeclaration) { 2336 assert(R.getTypePtr()->isFunctionType()); 2337 2338 DeclarationName Name = GetNameForDeclarator(D); 2339 FunctionDecl::StorageClass SC = FunctionDecl::None; 2340 switch (D.getDeclSpec().getStorageClassSpec()) { 2341 default: assert(0 && "Unknown storage class!"); 2342 case DeclSpec::SCS_auto: 2343 case DeclSpec::SCS_register: 2344 case DeclSpec::SCS_mutable: 2345 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2346 diag::err_typecheck_sclass_func); 2347 D.setInvalidType(); 2348 break; 2349 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2350 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2351 case DeclSpec::SCS_static: { 2352 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2353 // C99 6.7.1p5: 2354 // The declaration of an identifier for a function that has 2355 // block scope shall have no explicit storage-class specifier 2356 // other than extern 2357 // See also (C++ [dcl.stc]p4). 2358 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2359 diag::err_static_block_func); 2360 SC = FunctionDecl::None; 2361 } else 2362 SC = FunctionDecl::Static; 2363 break; 2364 } 2365 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2366 } 2367 2368 if (D.getDeclSpec().isThreadSpecified()) 2369 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2370 2371 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2372 bool isInline = D.getDeclSpec().isInlineSpecified(); 2373 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2374 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2375 2376 // Check that the return type is not an abstract class type. 2377 // For record types, this is done by the AbstractClassUsageDiagnoser once 2378 // the class has been completely parsed. 2379 if (!DC->isRecord() && 2380 RequireNonAbstractType(D.getIdentifierLoc(), 2381 R->getAsFunctionType()->getResultType(), 2382 diag::err_abstract_type_in_decl, 2383 AbstractReturnType)) 2384 D.setInvalidType(); 2385 2386 // Do not allow returning a objc interface by-value. 2387 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2388 Diag(D.getIdentifierLoc(), 2389 diag::err_object_cannot_be_passed_returned_by_value) << 0 2390 << R->getAsFunctionType()->getResultType(); 2391 D.setInvalidType(); 2392 } 2393 2394 // Check that we can declare a template here. 2395 if (TemplateParamLists.size() && 2396 CheckTemplateDeclScope(S, TemplateParamLists)) 2397 return 0; 2398 2399 bool isVirtualOkay = false; 2400 FunctionDecl *NewFD; 2401 if (isFriend) { 2402 // DC is the namespace in which the function is being declared. 2403 assert(DC->isFileContext() || D.getCXXScopeSpec().isSet()); 2404 2405 // C++ [class.friend]p5 2406 // A function can be defined in a friend declaration of a 2407 // class . . . . Such a function is implicitly inline. 2408 isInline |= IsFunctionDefinition; 2409 2410 NewFD = FriendFunctionDecl::Create(Context, DC, 2411 D.getIdentifierLoc(), Name, R, DInfo, 2412 isInline, 2413 D.getDeclSpec().getFriendSpecLoc()); 2414 2415 } else if (D.getKind() == Declarator::DK_Constructor) { 2416 // This is a C++ constructor declaration. 2417 assert(DC->isRecord() && 2418 "Constructors can only be declared in a member context"); 2419 2420 R = CheckConstructorDeclarator(D, R, SC); 2421 2422 // Create the new declaration 2423 NewFD = CXXConstructorDecl::Create(Context, 2424 cast<CXXRecordDecl>(DC), 2425 D.getIdentifierLoc(), Name, R, DInfo, 2426 isExplicit, isInline, 2427 /*isImplicitlyDeclared=*/false); 2428 } else if (D.getKind() == Declarator::DK_Destructor) { 2429 // This is a C++ destructor declaration. 2430 if (DC->isRecord()) { 2431 R = CheckDestructorDeclarator(D, SC); 2432 2433 NewFD = CXXDestructorDecl::Create(Context, 2434 cast<CXXRecordDecl>(DC), 2435 D.getIdentifierLoc(), Name, R, 2436 isInline, 2437 /*isImplicitlyDeclared=*/false); 2438 2439 isVirtualOkay = true; 2440 } else { 2441 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2442 2443 // Create a FunctionDecl to satisfy the function definition parsing 2444 // code path. 2445 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2446 Name, R, DInfo, SC, isInline, 2447 /*hasPrototype=*/true); 2448 D.setInvalidType(); 2449 } 2450 } else if (D.getKind() == Declarator::DK_Conversion) { 2451 if (!DC->isRecord()) { 2452 Diag(D.getIdentifierLoc(), 2453 diag::err_conv_function_not_member); 2454 return 0; 2455 } 2456 2457 CheckConversionDeclarator(D, R, SC); 2458 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2459 D.getIdentifierLoc(), Name, R, DInfo, 2460 isInline, isExplicit); 2461 2462 isVirtualOkay = true; 2463 } else if (DC->isRecord()) { 2464 // If the of the function is the same as the name of the record, then this 2465 // must be an invalid constructor that has a return type. 2466 // (The parser checks for a return type and makes the declarator a 2467 // constructor if it has no return type). 2468 // must have an invalid constructor that has a return type 2469 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2470 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2471 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2472 << SourceRange(D.getIdentifierLoc()); 2473 return 0; 2474 } 2475 2476 // This is a C++ method declaration. 2477 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2478 D.getIdentifierLoc(), Name, R, DInfo, 2479 (SC == FunctionDecl::Static), isInline); 2480 2481 isVirtualOkay = (SC != FunctionDecl::Static); 2482 } else { 2483 // Determine whether the function was written with a 2484 // prototype. This true when: 2485 // - we're in C++ (where every function has a prototype), 2486 // - there is a prototype in the declarator, or 2487 // - the type R of the function is some kind of typedef or other reference 2488 // to a type name (which eventually refers to a function type). 2489 bool HasPrototype = 2490 getLangOptions().CPlusPlus || 2491 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2492 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2493 2494 NewFD = FunctionDecl::Create(Context, DC, 2495 D.getIdentifierLoc(), 2496 Name, R, DInfo, SC, isInline, HasPrototype); 2497 } 2498 2499 if (D.isInvalidType()) 2500 NewFD->setInvalidDecl(); 2501 2502 // Set the lexical context. If the declarator has a C++ 2503 // scope specifier, the lexical context will be different 2504 // from the semantic context. 2505 NewFD->setLexicalDeclContext(CurContext); 2506 2507 // Match up the template parameter lists with the scope specifier, then 2508 // determine whether we have a template or a template specialization. 2509 FunctionTemplateDecl *FunctionTemplate = 0; 2510 if (TemplateParameterList *TemplateParams 2511 = MatchTemplateParametersToScopeSpecifier( 2512 D.getDeclSpec().getSourceRange().getBegin(), 2513 D.getCXXScopeSpec(), 2514 (TemplateParameterList**)TemplateParamLists.get(), 2515 TemplateParamLists.size())) { 2516 if (TemplateParams->size() > 0) { 2517 // This is a function template 2518 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2519 NewFD->getLocation(), 2520 Name, TemplateParams, 2521 NewFD); 2522 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2523 } else { 2524 // FIXME: Handle function template specializations 2525 } 2526 2527 // FIXME: Free this memory properly. 2528 TemplateParamLists.release(); 2529 } 2530 2531 // C++ [dcl.fct.spec]p5: 2532 // The virtual specifier shall only be used in declarations of 2533 // nonstatic class member functions that appear within a 2534 // member-specification of a class declaration; see 10.3. 2535 // 2536 if (isVirtual && !NewFD->isInvalidDecl()) { 2537 if (!isVirtualOkay) { 2538 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2539 diag::err_virtual_non_function); 2540 } else if (!CurContext->isRecord()) { 2541 // 'virtual' was specified outside of the class. 2542 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2543 << CodeModificationHint::CreateRemoval( 2544 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2545 } else { 2546 // Okay: Add virtual to the method. 2547 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2548 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2549 CurClass->setAggregate(false); 2550 CurClass->setPOD(false); 2551 CurClass->setEmpty(false); 2552 CurClass->setPolymorphic(true); 2553 CurClass->setHasTrivialConstructor(false); 2554 CurClass->setHasTrivialCopyConstructor(false); 2555 CurClass->setHasTrivialCopyAssignment(false); 2556 } 2557 } 2558 2559 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2560 // Look for virtual methods in base classes that this method might override. 2561 2562 BasePaths Paths; 2563 if (LookupInBases(cast<CXXRecordDecl>(DC), 2564 MemberLookupCriteria(NewMD), Paths)) { 2565 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2566 E = Paths.found_decls_end(); I != E; ++I) { 2567 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2568 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2569 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2570 NewMD->addOverriddenMethod(OldMD); 2571 } 2572 } 2573 } 2574 } 2575 2576 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2577 !CurContext->isRecord()) { 2578 // C++ [class.static]p1: 2579 // A data or function member of a class may be declared static 2580 // in a class definition, in which case it is a static member of 2581 // the class. 2582 2583 // Complain about the 'static' specifier if it's on an out-of-line 2584 // member function definition. 2585 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2586 diag::err_static_out_of_line) 2587 << CodeModificationHint::CreateRemoval( 2588 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2589 } 2590 2591 // Handle GNU asm-label extension (encoded as an attribute). 2592 if (Expr *E = (Expr*) D.getAsmLabel()) { 2593 // The parser guarantees this is a string. 2594 StringLiteral *SE = cast<StringLiteral>(E); 2595 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2596 SE->getByteLength()))); 2597 } 2598 2599 // Copy the parameter declarations from the declarator D to the function 2600 // declaration NewFD, if they are available. First scavenge them into Params. 2601 llvm::SmallVector<ParmVarDecl*, 16> Params; 2602 if (D.getNumTypeObjects() > 0) { 2603 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2604 2605 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2606 // function that takes no arguments, not a function that takes a 2607 // single void argument. 2608 // We let through "const void" here because Sema::GetTypeForDeclarator 2609 // already checks for that case. 2610 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2611 FTI.ArgInfo[0].Param && 2612 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2613 // Empty arg list, don't push any params. 2614 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2615 2616 // In C++, the empty parameter-type-list must be spelled "void"; a 2617 // typedef of void is not permitted. 2618 if (getLangOptions().CPlusPlus && 2619 Param->getType().getUnqualifiedType() != Context.VoidTy) 2620 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2621 // FIXME: Leaks decl? 2622 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2623 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2624 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2625 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2626 Param->setDeclContext(NewFD); 2627 Params.push_back(Param); 2628 } 2629 } 2630 2631 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2632 // When we're declaring a function with a typedef, typeof, etc as in the 2633 // following example, we'll need to synthesize (unnamed) 2634 // parameters for use in the declaration. 2635 // 2636 // @code 2637 // typedef void fn(int); 2638 // fn f; 2639 // @endcode 2640 2641 // Synthesize a parameter for each argument type. 2642 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2643 AE = FT->arg_type_end(); AI != AE; ++AI) { 2644 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2645 SourceLocation(), 0, 2646 *AI, /*DInfo=*/0, 2647 VarDecl::None, 0); 2648 Param->setImplicit(); 2649 Params.push_back(Param); 2650 } 2651 } else { 2652 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2653 "Should not need args for typedef of non-prototype fn"); 2654 } 2655 // Finally, we know we have the right number of parameters, install them. 2656 NewFD->setParams(Context, Params.data(), Params.size()); 2657 2658 // If name lookup finds a previous declaration that is not in the 2659 // same scope as the new declaration, this may still be an 2660 // acceptable redeclaration. 2661 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2662 !(NewFD->hasLinkage() && 2663 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2664 PrevDecl = 0; 2665 2666 // Perform semantic checking on the function declaration. 2667 bool OverloadableAttrRequired = false; // FIXME: HACK! 2668 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2669 /*FIXME:*/OverloadableAttrRequired); 2670 2671 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2672 // An out-of-line member function declaration must also be a 2673 // definition (C++ [dcl.meaning]p1). 2674 if (!IsFunctionDefinition && !isFriend) { 2675 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2676 << D.getCXXScopeSpec().getRange(); 2677 NewFD->setInvalidDecl(); 2678 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2679 // The user tried to provide an out-of-line definition for a 2680 // function that is a member of a class or namespace, but there 2681 // was no such member function declared (C++ [class.mfct]p2, 2682 // C++ [namespace.memdef]p2). For example: 2683 // 2684 // class X { 2685 // void f() const; 2686 // }; 2687 // 2688 // void X::f() { } // ill-formed 2689 // 2690 // Complain about this problem, and attempt to suggest close 2691 // matches (e.g., those that differ only in cv-qualifiers and 2692 // whether the parameter types are references). 2693 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2694 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2695 NewFD->setInvalidDecl(); 2696 2697 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2698 true); 2699 assert(!Prev.isAmbiguous() && 2700 "Cannot have an ambiguity in previous-declaration lookup"); 2701 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2702 Func != FuncEnd; ++Func) { 2703 if (isa<FunctionDecl>(*Func) && 2704 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2705 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2706 } 2707 2708 PrevDecl = 0; 2709 } 2710 } 2711 2712 // Handle attributes. We need to have merged decls when handling attributes 2713 // (for example to check for conflicts, etc). 2714 // FIXME: This needs to happen before we merge declarations. Then, 2715 // let attribute merging cope with attribute conflicts. 2716 ProcessDeclAttributes(S, NewFD, D); 2717 2718 // attributes declared post-definition are currently ignored 2719 if (PrevDecl) { 2720 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2721 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2722 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2723 Diag(Def->getLocation(), diag::note_previous_definition); 2724 } 2725 } 2726 2727 AddKnownFunctionAttributes(NewFD); 2728 2729 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2730 // If a function name is overloadable in C, then every function 2731 // with that name must be marked "overloadable". 2732 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2733 << Redeclaration << NewFD; 2734 if (PrevDecl) 2735 Diag(PrevDecl->getLocation(), 2736 diag::note_attribute_overloadable_prev_overload); 2737 NewFD->addAttr(::new (Context) OverloadableAttr()); 2738 } 2739 2740 // If this is a locally-scoped extern C function, update the 2741 // map of such names. 2742 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2743 && !NewFD->isInvalidDecl()) 2744 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2745 2746 // Set this FunctionDecl's range up to the right paren. 2747 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2748 2749 if (FunctionTemplate && NewFD->isInvalidDecl()) 2750 FunctionTemplate->setInvalidDecl(); 2751 2752 if (FunctionTemplate) 2753 return FunctionTemplate; 2754 2755 return NewFD; 2756} 2757 2758/// \brief Perform semantic checking of a new function declaration. 2759/// 2760/// Performs semantic analysis of the new function declaration 2761/// NewFD. This routine performs all semantic checking that does not 2762/// require the actual declarator involved in the declaration, and is 2763/// used both for the declaration of functions as they are parsed 2764/// (called via ActOnDeclarator) and for the declaration of functions 2765/// that have been instantiated via C++ template instantiation (called 2766/// via InstantiateDecl). 2767/// 2768/// This sets NewFD->isInvalidDecl() to true if there was an error. 2769void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2770 bool &Redeclaration, 2771 bool &OverloadableAttrRequired) { 2772 // If NewFD is already known erroneous, don't do any of this checking. 2773 if (NewFD->isInvalidDecl()) 2774 return; 2775 2776 if (NewFD->getResultType()->isVariablyModifiedType()) { 2777 // Functions returning a variably modified type violate C99 6.7.5.2p2 2778 // because all functions have linkage. 2779 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2780 return NewFD->setInvalidDecl(); 2781 } 2782 2783 if (NewFD->isMain(Context)) CheckMain(NewFD); 2784 2785 // Semantic checking for this function declaration (in isolation). 2786 if (getLangOptions().CPlusPlus) { 2787 // C++-specific checks. 2788 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2789 CheckConstructor(Constructor); 2790 } else if (isa<CXXDestructorDecl>(NewFD)) { 2791 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2792 QualType ClassType = Context.getTypeDeclType(Record); 2793 if (!ClassType->isDependentType()) { 2794 DeclarationName Name 2795 = Context.DeclarationNames.getCXXDestructorName( 2796 Context.getCanonicalType(ClassType)); 2797 if (NewFD->getDeclName() != Name) { 2798 Diag(NewFD->getLocation(), diag::err_destructor_name); 2799 return NewFD->setInvalidDecl(); 2800 } 2801 } 2802 Record->setUserDeclaredDestructor(true); 2803 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2804 // user-defined destructor. 2805 Record->setPOD(false); 2806 2807 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2808 // declared destructor. 2809 // FIXME: C++0x: don't do this for "= default" destructors 2810 Record->setHasTrivialDestructor(false); 2811 } else if (CXXConversionDecl *Conversion 2812 = dyn_cast<CXXConversionDecl>(NewFD)) 2813 ActOnConversionDeclarator(Conversion); 2814 2815 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2816 if (NewFD->isOverloadedOperator() && 2817 CheckOverloadedOperatorDeclaration(NewFD)) 2818 return NewFD->setInvalidDecl(); 2819 } 2820 2821 // C99 6.7.4p6: 2822 // [... ] For a function with external linkage, the following 2823 // restrictions apply: [...] If all of the file scope declarations 2824 // for a function in a translation unit include the inline 2825 // function specifier without extern, then the definition in that 2826 // translation unit is an inline definition. An inline definition 2827 // does not provide an external definition for the function, and 2828 // does not forbid an external definition in another translation 2829 // unit. 2830 // 2831 // Here we determine whether this function, in isolation, would be a 2832 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2833 // previous declarations. 2834 if (NewFD->isInline() && getLangOptions().C99 && 2835 NewFD->getStorageClass() == FunctionDecl::None && 2836 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2837 NewFD->setC99InlineDefinition(true); 2838 2839 // Check for a previous declaration of this name. 2840 if (!PrevDecl && NewFD->isExternC(Context)) { 2841 // Since we did not find anything by this name and we're declaring 2842 // an extern "C" function, look for a non-visible extern "C" 2843 // declaration with the same name. 2844 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2845 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2846 if (Pos != LocallyScopedExternalDecls.end()) 2847 PrevDecl = Pos->second; 2848 } 2849 2850 // Merge or overload the declaration with an existing declaration of 2851 // the same name, if appropriate. 2852 if (PrevDecl) { 2853 // Determine whether NewFD is an overload of PrevDecl or 2854 // a declaration that requires merging. If it's an overload, 2855 // there's no more work to do here; we'll just add the new 2856 // function to the scope. 2857 OverloadedFunctionDecl::function_iterator MatchedDecl; 2858 2859 if (!getLangOptions().CPlusPlus && 2860 AllowOverloadingOfFunction(PrevDecl, Context)) { 2861 OverloadableAttrRequired = true; 2862 2863 // Functions marked "overloadable" must have a prototype (that 2864 // we can't get through declaration merging). 2865 if (!NewFD->getType()->getAsFunctionProtoType()) { 2866 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2867 << NewFD; 2868 Redeclaration = true; 2869 2870 // Turn this into a variadic function with no parameters. 2871 QualType R = Context.getFunctionType( 2872 NewFD->getType()->getAsFunctionType()->getResultType(), 2873 0, 0, true, 0); 2874 NewFD->setType(R); 2875 return NewFD->setInvalidDecl(); 2876 } 2877 } 2878 2879 if (PrevDecl && 2880 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2881 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2882 !isa<UsingDecl>(PrevDecl)) { 2883 Redeclaration = true; 2884 Decl *OldDecl = PrevDecl; 2885 2886 // If PrevDecl was an overloaded function, extract the 2887 // FunctionDecl that matched. 2888 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2889 OldDecl = *MatchedDecl; 2890 2891 // NewFD and OldDecl represent declarations that need to be 2892 // merged. 2893 if (MergeFunctionDecl(NewFD, OldDecl)) 2894 return NewFD->setInvalidDecl(); 2895 2896 if (FunctionTemplateDecl *OldTemplateDecl 2897 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2898 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2899 else { 2900 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2901 NewFD->setAccess(OldDecl->getAccess()); 2902 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2903 } 2904 } 2905 } 2906 2907 // In C++, check default arguments now that we have merged decls. Unless 2908 // the lexical context is the class, because in this case this is done 2909 // during delayed parsing anyway. 2910 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2911 CheckCXXDefaultArguments(NewFD); 2912} 2913 2914void Sema::CheckMain(FunctionDecl* FD) { 2915 // C++ [basic.start.main]p3: A program that declares main to be inline 2916 // or static is ill-formed. 2917 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2918 // shall not appear in a declaration of main. 2919 // static main is not an error under C99, but we should warn about it. 2920 bool isInline = FD->isInline(); 2921 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2922 if (isInline || isStatic) { 2923 unsigned diagID = diag::warn_unusual_main_decl; 2924 if (isInline || getLangOptions().CPlusPlus) 2925 diagID = diag::err_unusual_main_decl; 2926 2927 int which = isStatic + (isInline << 1) - 1; 2928 Diag(FD->getLocation(), diagID) << which; 2929 } 2930 2931 QualType T = FD->getType(); 2932 assert(T->isFunctionType() && "function decl is not of function type"); 2933 const FunctionType* FT = T->getAsFunctionType(); 2934 2935 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2936 // TODO: add a replacement fixit to turn the return type into 'int'. 2937 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2938 FD->setInvalidDecl(true); 2939 } 2940 2941 // Treat protoless main() as nullary. 2942 if (isa<FunctionNoProtoType>(FT)) return; 2943 2944 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2945 unsigned nparams = FTP->getNumArgs(); 2946 assert(FD->getNumParams() == nparams); 2947 2948 if (nparams > 3) { 2949 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2950 FD->setInvalidDecl(true); 2951 nparams = 3; 2952 } 2953 2954 // FIXME: a lot of the following diagnostics would be improved 2955 // if we had some location information about types. 2956 2957 QualType CharPP = 2958 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2959 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2960 2961 for (unsigned i = 0; i < nparams; ++i) { 2962 QualType AT = FTP->getArgType(i); 2963 2964 bool mismatch = true; 2965 2966 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2967 mismatch = false; 2968 else if (Expected[i] == CharPP) { 2969 // As an extension, the following forms are okay: 2970 // char const ** 2971 // char const * const * 2972 // char * const * 2973 2974 QualifierSet qs; 2975 const PointerType* PT; 2976 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 2977 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 2978 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 2979 qs.removeConst(); 2980 mismatch = !qs.empty(); 2981 } 2982 } 2983 2984 if (mismatch) { 2985 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 2986 // TODO: suggest replacing given type with expected type 2987 FD->setInvalidDecl(true); 2988 } 2989 } 2990 2991 if (nparams == 1 && !FD->isInvalidDecl()) { 2992 Diag(FD->getLocation(), diag::warn_main_one_arg); 2993 } 2994} 2995 2996bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2997 // FIXME: Need strict checking. In C89, we need to check for 2998 // any assignment, increment, decrement, function-calls, or 2999 // commas outside of a sizeof. In C99, it's the same list, 3000 // except that the aforementioned are allowed in unevaluated 3001 // expressions. Everything else falls under the 3002 // "may accept other forms of constant expressions" exception. 3003 // (We never end up here for C++, so the constant expression 3004 // rules there don't matter.) 3005 if (Init->isConstantInitializer(Context)) 3006 return false; 3007 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3008 << Init->getSourceRange(); 3009 return true; 3010} 3011 3012void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3013 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3014} 3015 3016/// AddInitializerToDecl - Adds the initializer Init to the 3017/// declaration dcl. If DirectInit is true, this is C++ direct 3018/// initialization rather than copy initialization. 3019void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3020 Decl *RealDecl = dcl.getAs<Decl>(); 3021 // If there is no declaration, there was an error parsing it. Just ignore 3022 // the initializer. 3023 if (RealDecl == 0) 3024 return; 3025 3026 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3027 // With declarators parsed the way they are, the parser cannot 3028 // distinguish between a normal initializer and a pure-specifier. 3029 // Thus this grotesque test. 3030 IntegerLiteral *IL; 3031 Expr *Init = static_cast<Expr *>(init.get()); 3032 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3033 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3034 if (Method->isVirtualAsWritten()) { 3035 Method->setPure(); 3036 3037 // A class is abstract if at least one function is pure virtual. 3038 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3039 } else if (!Method->isInvalidDecl()) { 3040 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3041 << Method->getDeclName() << Init->getSourceRange(); 3042 Method->setInvalidDecl(); 3043 } 3044 } else { 3045 Diag(Method->getLocation(), diag::err_member_function_initialization) 3046 << Method->getDeclName() << Init->getSourceRange(); 3047 Method->setInvalidDecl(); 3048 } 3049 return; 3050 } 3051 3052 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3053 if (!VDecl) { 3054 if (getLangOptions().CPlusPlus && 3055 RealDecl->getLexicalDeclContext()->isRecord() && 3056 isa<NamedDecl>(RealDecl)) 3057 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3058 << cast<NamedDecl>(RealDecl)->getDeclName(); 3059 else 3060 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3061 RealDecl->setInvalidDecl(); 3062 return; 3063 } 3064 3065 if (!VDecl->getType()->isArrayType() && 3066 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3067 diag::err_typecheck_decl_incomplete_type)) { 3068 RealDecl->setInvalidDecl(); 3069 return; 3070 } 3071 3072 const VarDecl *Def = 0; 3073 if (VDecl->getDefinition(Def)) { 3074 Diag(VDecl->getLocation(), diag::err_redefinition) 3075 << VDecl->getDeclName(); 3076 Diag(Def->getLocation(), diag::note_previous_definition); 3077 VDecl->setInvalidDecl(); 3078 return; 3079 } 3080 3081 // Take ownership of the expression, now that we're sure we have somewhere 3082 // to put it. 3083 Expr *Init = init.takeAs<Expr>(); 3084 assert(Init && "missing initializer"); 3085 3086 // Get the decls type and save a reference for later, since 3087 // CheckInitializerTypes may change it. 3088 QualType DclT = VDecl->getType(), SavT = DclT; 3089 if (VDecl->isBlockVarDecl()) { 3090 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3091 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3092 VDecl->setInvalidDecl(); 3093 } else if (!VDecl->isInvalidDecl()) { 3094 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3095 VDecl->getDeclName(), DirectInit)) 3096 VDecl->setInvalidDecl(); 3097 3098 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3099 // Don't check invalid declarations to avoid emitting useless diagnostics. 3100 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3101 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3102 CheckForConstantInitializer(Init, DclT); 3103 } 3104 } 3105 } else if (VDecl->isStaticDataMember() && 3106 VDecl->getLexicalDeclContext()->isRecord()) { 3107 // This is an in-class initialization for a static data member, e.g., 3108 // 3109 // struct S { 3110 // static const int value = 17; 3111 // }; 3112 3113 // Attach the initializer 3114 VDecl->setInit(Context, Init); 3115 3116 // C++ [class.mem]p4: 3117 // A member-declarator can contain a constant-initializer only 3118 // if it declares a static member (9.4) of const integral or 3119 // const enumeration type, see 9.4.2. 3120 QualType T = VDecl->getType(); 3121 if (!T->isDependentType() && 3122 (!Context.getCanonicalType(T).isConstQualified() || 3123 !T->isIntegralType())) { 3124 Diag(VDecl->getLocation(), diag::err_member_initialization) 3125 << VDecl->getDeclName() << Init->getSourceRange(); 3126 VDecl->setInvalidDecl(); 3127 } else { 3128 // C++ [class.static.data]p4: 3129 // If a static data member is of const integral or const 3130 // enumeration type, its declaration in the class definition 3131 // can specify a constant-initializer which shall be an 3132 // integral constant expression (5.19). 3133 if (!Init->isTypeDependent() && 3134 !Init->getType()->isIntegralType()) { 3135 // We have a non-dependent, non-integral or enumeration type. 3136 Diag(Init->getSourceRange().getBegin(), 3137 diag::err_in_class_initializer_non_integral_type) 3138 << Init->getType() << Init->getSourceRange(); 3139 VDecl->setInvalidDecl(); 3140 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3141 // Check whether the expression is a constant expression. 3142 llvm::APSInt Value; 3143 SourceLocation Loc; 3144 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3145 Diag(Loc, diag::err_in_class_initializer_non_constant) 3146 << Init->getSourceRange(); 3147 VDecl->setInvalidDecl(); 3148 } else if (!VDecl->getType()->isDependentType()) 3149 ImpCastExprToType(Init, VDecl->getType()); 3150 } 3151 } 3152 } else if (VDecl->isFileVarDecl()) { 3153 if (VDecl->getStorageClass() == VarDecl::Extern) 3154 Diag(VDecl->getLocation(), diag::warn_extern_init); 3155 if (!VDecl->isInvalidDecl()) 3156 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3157 VDecl->getDeclName(), DirectInit)) 3158 VDecl->setInvalidDecl(); 3159 3160 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3161 // Don't check invalid declarations to avoid emitting useless diagnostics. 3162 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3163 // C99 6.7.8p4. All file scoped initializers need to be constant. 3164 CheckForConstantInitializer(Init, DclT); 3165 } 3166 } 3167 // If the type changed, it means we had an incomplete type that was 3168 // completed by the initializer. For example: 3169 // int ary[] = { 1, 3, 5 }; 3170 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3171 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3172 VDecl->setType(DclT); 3173 Init->setType(DclT); 3174 } 3175 3176 Init = MaybeCreateCXXExprWithTemporaries(Init, 3177 /*ShouldDestroyTemporaries=*/true); 3178 // Attach the initializer to the decl. 3179 VDecl->setInit(Context, Init); 3180 3181 // If the previous declaration of VDecl was a tentative definition, 3182 // remove it from the set of tentative definitions. 3183 if (VDecl->getPreviousDeclaration() && 3184 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3185 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 3186 = TentativeDefinitions.find(VDecl->getDeclName()); 3187 assert(Pos != TentativeDefinitions.end() && 3188 "Unrecorded tentative definition?"); 3189 TentativeDefinitions.erase(Pos); 3190 } 3191 3192 return; 3193} 3194 3195void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3196 bool TypeContainsUndeducedAuto) { 3197 Decl *RealDecl = dcl.getAs<Decl>(); 3198 3199 // If there is no declaration, there was an error parsing it. Just ignore it. 3200 if (RealDecl == 0) 3201 return; 3202 3203 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3204 QualType Type = Var->getType(); 3205 3206 // Record tentative definitions. 3207 if (Var->isTentativeDefinition(Context)) 3208 TentativeDefinitions[Var->getDeclName()] = Var; 3209 3210 // C++ [dcl.init.ref]p3: 3211 // The initializer can be omitted for a reference only in a 3212 // parameter declaration (8.3.5), in the declaration of a 3213 // function return type, in the declaration of a class member 3214 // within its class declaration (9.2), and where the extern 3215 // specifier is explicitly used. 3216 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3217 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3218 << Var->getDeclName() 3219 << SourceRange(Var->getLocation(), Var->getLocation()); 3220 Var->setInvalidDecl(); 3221 return; 3222 } 3223 3224 // C++0x [dcl.spec.auto]p3 3225 if (TypeContainsUndeducedAuto) { 3226 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3227 << Var->getDeclName() << Type; 3228 Var->setInvalidDecl(); 3229 return; 3230 } 3231 3232 // C++ [dcl.init]p9: 3233 // 3234 // If no initializer is specified for an object, and the object 3235 // is of (possibly cv-qualified) non-POD class type (or array 3236 // thereof), the object shall be default-initialized; if the 3237 // object is of const-qualified type, the underlying class type 3238 // shall have a user-declared default constructor. 3239 if (getLangOptions().CPlusPlus) { 3240 QualType InitType = Type; 3241 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3242 InitType = Array->getElementType(); 3243 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 3244 InitType->isRecordType() && !InitType->isDependentType()) { 3245 CXXRecordDecl *RD = 3246 cast<CXXRecordDecl>(InitType->getAs<RecordType>()->getDecl()); 3247 CXXConstructorDecl *Constructor = 0; 3248 if (!RequireCompleteType(Var->getLocation(), InitType, 3249 diag::err_invalid_incomplete_type_use)) 3250 Constructor 3251 = PerformInitializationByConstructor(InitType, 0, 0, 3252 Var->getLocation(), 3253 SourceRange(Var->getLocation(), 3254 Var->getLocation()), 3255 Var->getDeclName(), 3256 IK_Default); 3257 if (!Constructor) 3258 Var->setInvalidDecl(); 3259 else { 3260 if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()) 3261 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 3262 FinalizeVarWithDestructor(Var, InitType); 3263 } 3264 } 3265 } 3266 3267#if 0 3268 // FIXME: Temporarily disabled because we are not properly parsing 3269 // linkage specifications on declarations, e.g., 3270 // 3271 // extern "C" const CGPoint CGPointerZero; 3272 // 3273 // C++ [dcl.init]p9: 3274 // 3275 // If no initializer is specified for an object, and the 3276 // object is of (possibly cv-qualified) non-POD class type (or 3277 // array thereof), the object shall be default-initialized; if 3278 // the object is of const-qualified type, the underlying class 3279 // type shall have a user-declared default 3280 // constructor. Otherwise, if no initializer is specified for 3281 // an object, the object and its subobjects, if any, have an 3282 // indeterminate initial value; if the object or any of its 3283 // subobjects are of const-qualified type, the program is 3284 // ill-formed. 3285 // 3286 // This isn't technically an error in C, so we don't diagnose it. 3287 // 3288 // FIXME: Actually perform the POD/user-defined default 3289 // constructor check. 3290 if (getLangOptions().CPlusPlus && 3291 Context.getCanonicalType(Type).isConstQualified() && 3292 !Var->hasExternalStorage()) 3293 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3294 << Var->getName() 3295 << SourceRange(Var->getLocation(), Var->getLocation()); 3296#endif 3297 } 3298} 3299 3300Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3301 DeclPtrTy *Group, 3302 unsigned NumDecls) { 3303 llvm::SmallVector<Decl*, 8> Decls; 3304 3305 if (DS.isTypeSpecOwned()) 3306 Decls.push_back((Decl*)DS.getTypeRep()); 3307 3308 for (unsigned i = 0; i != NumDecls; ++i) 3309 if (Decl *D = Group[i].getAs<Decl>()) 3310 Decls.push_back(D); 3311 3312 // Perform semantic analysis that depends on having fully processed both 3313 // the declarator and initializer. 3314 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3315 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3316 if (!IDecl) 3317 continue; 3318 QualType T = IDecl->getType(); 3319 3320 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3321 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3322 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3323 if (!IDecl->isInvalidDecl() && 3324 RequireCompleteType(IDecl->getLocation(), T, 3325 diag::err_typecheck_decl_incomplete_type)) 3326 IDecl->setInvalidDecl(); 3327 } 3328 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3329 // object that has file scope without an initializer, and without a 3330 // storage-class specifier or with the storage-class specifier "static", 3331 // constitutes a tentative definition. Note: A tentative definition with 3332 // external linkage is valid (C99 6.2.2p5). 3333 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3334 if (const IncompleteArrayType *ArrayT 3335 = Context.getAsIncompleteArrayType(T)) { 3336 if (RequireCompleteType(IDecl->getLocation(), 3337 ArrayT->getElementType(), 3338 diag::err_illegal_decl_array_incomplete_type)) 3339 IDecl->setInvalidDecl(); 3340 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3341 // C99 6.9.2p3: If the declaration of an identifier for an object is 3342 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3343 // declared type shall not be an incomplete type. 3344 // NOTE: code such as the following 3345 // static struct s; 3346 // struct s { int a; }; 3347 // is accepted by gcc. Hence here we issue a warning instead of 3348 // an error and we do not invalidate the static declaration. 3349 // NOTE: to avoid multiple warnings, only check the first declaration. 3350 if (IDecl->getPreviousDeclaration() == 0) 3351 RequireCompleteType(IDecl->getLocation(), T, 3352 diag::ext_typecheck_decl_incomplete_type); 3353 } 3354 } 3355 } 3356 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3357 Decls.data(), Decls.size())); 3358} 3359 3360 3361/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3362/// to introduce parameters into function prototype scope. 3363Sema::DeclPtrTy 3364Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3365 const DeclSpec &DS = D.getDeclSpec(); 3366 3367 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3368 VarDecl::StorageClass StorageClass = VarDecl::None; 3369 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3370 StorageClass = VarDecl::Register; 3371 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3372 Diag(DS.getStorageClassSpecLoc(), 3373 diag::err_invalid_storage_class_in_func_decl); 3374 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3375 } 3376 3377 if (D.getDeclSpec().isThreadSpecified()) 3378 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3379 3380 DiagnoseFunctionSpecifiers(D); 3381 3382 // Check that there are no default arguments inside the type of this 3383 // parameter (C++ only). 3384 if (getLangOptions().CPlusPlus) 3385 CheckExtraCXXDefaultArguments(D); 3386 3387 DeclaratorInfo *DInfo = 0; 3388 TagDecl *OwnedDecl = 0; 3389 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3390 &OwnedDecl); 3391 3392 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3393 // C++ [dcl.fct]p6: 3394 // Types shall not be defined in return or parameter types. 3395 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3396 << Context.getTypeDeclType(OwnedDecl); 3397 } 3398 3399 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3400 // Can this happen for params? We already checked that they don't conflict 3401 // among each other. Here they can only shadow globals, which is ok. 3402 IdentifierInfo *II = D.getIdentifier(); 3403 if (II) { 3404 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3405 if (PrevDecl->isTemplateParameter()) { 3406 // Maybe we will complain about the shadowed template parameter. 3407 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3408 // Just pretend that we didn't see the previous declaration. 3409 PrevDecl = 0; 3410 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3411 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3412 3413 // Recover by removing the name 3414 II = 0; 3415 D.SetIdentifier(0, D.getIdentifierLoc()); 3416 } 3417 } 3418 } 3419 3420 // Parameters can not be abstract class types. 3421 // For record types, this is done by the AbstractClassUsageDiagnoser once 3422 // the class has been completely parsed. 3423 if (!CurContext->isRecord() && 3424 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3425 diag::err_abstract_type_in_decl, 3426 AbstractParamType)) 3427 D.setInvalidType(true); 3428 3429 QualType T = adjustParameterType(parmDeclType); 3430 3431 ParmVarDecl *New; 3432 if (T == parmDeclType) // parameter type did not need adjustment 3433 New = ParmVarDecl::Create(Context, CurContext, 3434 D.getIdentifierLoc(), II, 3435 parmDeclType, DInfo, StorageClass, 3436 0); 3437 else // keep track of both the adjusted and unadjusted types 3438 New = OriginalParmVarDecl::Create(Context, CurContext, 3439 D.getIdentifierLoc(), II, T, DInfo, 3440 parmDeclType, StorageClass, 0); 3441 3442 if (D.isInvalidType()) 3443 New->setInvalidDecl(); 3444 3445 // Parameter declarators cannot be interface types. All ObjC objects are 3446 // passed by reference. 3447 if (T->isObjCInterfaceType()) { 3448 Diag(D.getIdentifierLoc(), 3449 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3450 New->setInvalidDecl(); 3451 } 3452 3453 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3454 if (D.getCXXScopeSpec().isSet()) { 3455 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3456 << D.getCXXScopeSpec().getRange(); 3457 New->setInvalidDecl(); 3458 } 3459 3460 // Add the parameter declaration into this scope. 3461 S->AddDecl(DeclPtrTy::make(New)); 3462 if (II) 3463 IdResolver.AddDecl(New); 3464 3465 ProcessDeclAttributes(S, New, D); 3466 3467 if (New->hasAttr<BlocksAttr>()) { 3468 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3469 } 3470 return DeclPtrTy::make(New); 3471} 3472 3473void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3474 SourceLocation LocAfterDecls) { 3475 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3476 "Not a function declarator!"); 3477 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3478 3479 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3480 // for a K&R function. 3481 if (!FTI.hasPrototype) { 3482 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3483 --i; 3484 if (FTI.ArgInfo[i].Param == 0) { 3485 std::string Code = " int "; 3486 Code += FTI.ArgInfo[i].Ident->getName(); 3487 Code += ";\n"; 3488 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3489 << FTI.ArgInfo[i].Ident 3490 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3491 3492 // Implicitly declare the argument as type 'int' for lack of a better 3493 // type. 3494 DeclSpec DS; 3495 const char* PrevSpec; // unused 3496 unsigned DiagID; // unused 3497 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3498 PrevSpec, DiagID); 3499 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3500 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3501 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3502 } 3503 } 3504 } 3505} 3506 3507Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3508 Declarator &D) { 3509 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3510 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3511 "Not a function declarator!"); 3512 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3513 3514 if (FTI.hasPrototype) { 3515 // FIXME: Diagnose arguments without names in C. 3516 } 3517 3518 Scope *ParentScope = FnBodyScope->getParent(); 3519 3520 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3521 MultiTemplateParamsArg(*this), 3522 /*IsFunctionDefinition=*/true); 3523 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3524} 3525 3526Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3527 if (!D) 3528 return D; 3529 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 3530 3531 CurFunctionNeedsScopeChecking = false; 3532 3533 // See if this is a redefinition. 3534 const FunctionDecl *Definition; 3535 if (FD->getBody(Definition)) { 3536 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3537 Diag(Definition->getLocation(), diag::note_previous_definition); 3538 } 3539 3540 // Builtin functions cannot be defined. 3541 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3542 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3543 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3544 FD->setInvalidDecl(); 3545 } 3546 } 3547 3548 // The return type of a function definition must be complete 3549 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3550 QualType ResultType = FD->getResultType(); 3551 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3552 !FD->isInvalidDecl() && 3553 RequireCompleteType(FD->getLocation(), ResultType, 3554 diag::err_func_def_incomplete_result)) 3555 FD->setInvalidDecl(); 3556 3557 // GNU warning -Wmissing-prototypes: 3558 // Warn if a global function is defined without a previous 3559 // prototype declaration. This warning is issued even if the 3560 // definition itself provides a prototype. The aim is to detect 3561 // global functions that fail to be declared in header files. 3562 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3563 !FD->isMain(Context)) { 3564 bool MissingPrototype = true; 3565 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3566 Prev; Prev = Prev->getPreviousDeclaration()) { 3567 // Ignore any declarations that occur in function or method 3568 // scope, because they aren't visible from the header. 3569 if (Prev->getDeclContext()->isFunctionOrMethod()) 3570 continue; 3571 3572 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3573 break; 3574 } 3575 3576 if (MissingPrototype) 3577 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3578 } 3579 3580 if (FnBodyScope) 3581 PushDeclContext(FnBodyScope, FD); 3582 3583 // Check the validity of our function parameters 3584 CheckParmsForFunctionDef(FD); 3585 3586 // Introduce our parameters into the function scope 3587 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3588 ParmVarDecl *Param = FD->getParamDecl(p); 3589 Param->setOwningFunction(FD); 3590 3591 // If this has an identifier, add it to the scope stack. 3592 if (Param->getIdentifier() && FnBodyScope) 3593 PushOnScopeChains(Param, FnBodyScope); 3594 } 3595 3596 // Checking attributes of current function definition 3597 // dllimport attribute. 3598 if (FD->getAttr<DLLImportAttr>() && 3599 (!FD->getAttr<DLLExportAttr>())) { 3600 // dllimport attribute cannot be applied to definition. 3601 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3602 Diag(FD->getLocation(), 3603 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3604 << "dllimport"; 3605 FD->setInvalidDecl(); 3606 return DeclPtrTy::make(FD); 3607 } else { 3608 // If a symbol previously declared dllimport is later defined, the 3609 // attribute is ignored in subsequent references, and a warning is 3610 // emitted. 3611 Diag(FD->getLocation(), 3612 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3613 << FD->getNameAsCString() << "dllimport"; 3614 } 3615 } 3616 return DeclPtrTy::make(FD); 3617} 3618 3619Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3620 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3621} 3622 3623Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3624 bool IsInstantiation) { 3625 Decl *dcl = D.getAs<Decl>(); 3626 Stmt *Body = BodyArg.takeAs<Stmt>(); 3627 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3628 FD->setBody(Body); 3629 if (FD->isMain(Context)) 3630 // C and C++ allow for main to automagically return 0. 3631 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3632 FD->setHasImplicitReturnZero(true); 3633 else 3634 CheckFallThroughForFunctionDef(FD, Body); 3635 3636 if (!FD->isInvalidDecl()) 3637 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3638 3639 // C++ [basic.def.odr]p2: 3640 // [...] A virtual member function is used if it is not pure. [...] 3641 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3642 if (Method->isVirtual() && !Method->isPure()) 3643 MarkDeclarationReferenced(Method->getLocation(), Method); 3644 3645 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3646 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3647 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3648 MD->setBody(Body); 3649 CheckFallThroughForFunctionDef(MD, Body); 3650 MD->setEndLoc(Body->getLocEnd()); 3651 3652 if (!MD->isInvalidDecl()) 3653 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3654 } else { 3655 Body->Destroy(Context); 3656 return DeclPtrTy(); 3657 } 3658 if (!IsInstantiation) 3659 PopDeclContext(); 3660 3661 // Verify and clean out per-function state. 3662 3663 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3664 3665 // Check goto/label use. 3666 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3667 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3668 LabelStmt *L = I->second; 3669 3670 // Verify that we have no forward references left. If so, there was a goto 3671 // or address of a label taken, but no definition of it. Label fwd 3672 // definitions are indicated with a null substmt. 3673 if (L->getSubStmt() != 0) 3674 continue; 3675 3676 // Emit error. 3677 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3678 3679 // At this point, we have gotos that use the bogus label. Stitch it into 3680 // the function body so that they aren't leaked and that the AST is well 3681 // formed. 3682 if (Body == 0) { 3683 // The whole function wasn't parsed correctly, just delete this. 3684 L->Destroy(Context); 3685 continue; 3686 } 3687 3688 // Otherwise, the body is valid: we want to stitch the label decl into the 3689 // function somewhere so that it is properly owned and so that the goto 3690 // has a valid target. Do this by creating a new compound stmt with the 3691 // label in it. 3692 3693 // Give the label a sub-statement. 3694 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3695 3696 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3697 cast<CXXTryStmt>(Body)->getTryBlock() : 3698 cast<CompoundStmt>(Body); 3699 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3700 Elements.push_back(L); 3701 Compound->setStmts(Context, &Elements[0], Elements.size()); 3702 } 3703 FunctionLabelMap.clear(); 3704 3705 if (!Body) return D; 3706 3707 // Verify that that gotos and switch cases don't jump into scopes illegally. 3708 if (CurFunctionNeedsScopeChecking) 3709 DiagnoseInvalidJumps(Body); 3710 3711 // C++ constructors that have function-try-blocks can't have return 3712 // statements in the handlers of that block. (C++ [except.handle]p14) 3713 // Verify this. 3714 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3715 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3716 3717 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3718 Destructor->computeBaseOrMembersToDestroy(Context); 3719 return D; 3720} 3721 3722/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3723/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3724NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3725 IdentifierInfo &II, Scope *S) { 3726 // Before we produce a declaration for an implicitly defined 3727 // function, see whether there was a locally-scoped declaration of 3728 // this name as a function or variable. If so, use that 3729 // (non-visible) declaration, and complain about it. 3730 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3731 = LocallyScopedExternalDecls.find(&II); 3732 if (Pos != LocallyScopedExternalDecls.end()) { 3733 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3734 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3735 return Pos->second; 3736 } 3737 3738 // Extension in C99. Legal in C90, but warn about it. 3739 if (getLangOptions().C99) 3740 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3741 else 3742 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3743 3744 // FIXME: handle stuff like: 3745 // void foo() { extern float X(); } 3746 // void bar() { X(); } <-- implicit decl for X in another scope. 3747 3748 // Set a Declarator for the implicit definition: int foo(); 3749 const char *Dummy; 3750 DeclSpec DS; 3751 unsigned DiagID; 3752 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3753 Error = Error; // Silence warning. 3754 assert(!Error && "Error setting up implicit decl!"); 3755 Declarator D(DS, Declarator::BlockContext); 3756 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3757 0, 0, false, SourceLocation(), 3758 false, 0,0,0, Loc, Loc, D), 3759 SourceLocation()); 3760 D.SetIdentifier(&II, Loc); 3761 3762 // Insert this function into translation-unit scope. 3763 3764 DeclContext *PrevDC = CurContext; 3765 CurContext = Context.getTranslationUnitDecl(); 3766 3767 FunctionDecl *FD = 3768 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3769 FD->setImplicit(); 3770 3771 CurContext = PrevDC; 3772 3773 AddKnownFunctionAttributes(FD); 3774 3775 return FD; 3776} 3777 3778/// \brief Adds any function attributes that we know a priori based on 3779/// the declaration of this function. 3780/// 3781/// These attributes can apply both to implicitly-declared builtins 3782/// (like __builtin___printf_chk) or to library-declared functions 3783/// like NSLog or printf. 3784void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3785 if (FD->isInvalidDecl()) 3786 return; 3787 3788 // If this is a built-in function, map its builtin attributes to 3789 // actual attributes. 3790 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3791 // Handle printf-formatting attributes. 3792 unsigned FormatIdx; 3793 bool HasVAListArg; 3794 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3795 if (!FD->getAttr<FormatAttr>()) 3796 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3797 HasVAListArg ? 0 : FormatIdx + 2)); 3798 } 3799 3800 // Mark const if we don't care about errno and that is the only 3801 // thing preventing the function from being const. This allows 3802 // IRgen to use LLVM intrinsics for such functions. 3803 if (!getLangOptions().MathErrno && 3804 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3805 if (!FD->getAttr<ConstAttr>()) 3806 FD->addAttr(::new (Context) ConstAttr()); 3807 } 3808 3809 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3810 FD->addAttr(::new (Context) NoReturnAttr()); 3811 } 3812 3813 IdentifierInfo *Name = FD->getIdentifier(); 3814 if (!Name) 3815 return; 3816 if ((!getLangOptions().CPlusPlus && 3817 FD->getDeclContext()->isTranslationUnit()) || 3818 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3819 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3820 LinkageSpecDecl::lang_c)) { 3821 // Okay: this could be a libc/libm/Objective-C function we know 3822 // about. 3823 } else 3824 return; 3825 3826 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3827 // FIXME: NSLog and NSLogv should be target specific 3828 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3829 // FIXME: We known better than our headers. 3830 const_cast<FormatAttr *>(Format)->setType("printf"); 3831 } else 3832 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3833 Name->isStr("NSLogv") ? 0 : 2)); 3834 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3835 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3836 // target-specific builtins, perhaps? 3837 if (!FD->getAttr<FormatAttr>()) 3838 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3839 Name->isStr("vasprintf") ? 0 : 3)); 3840 } 3841} 3842 3843TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3844 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3845 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3846 3847 // Scope manipulation handled by caller. 3848 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3849 D.getIdentifierLoc(), 3850 D.getIdentifier(), 3851 T); 3852 3853 if (TagType *TT = dyn_cast<TagType>(T)) { 3854 TagDecl *TD = TT->getDecl(); 3855 3856 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3857 // keep track of the TypedefDecl. 3858 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3859 TD->setTypedefForAnonDecl(NewTD); 3860 } 3861 3862 if (D.isInvalidType()) 3863 NewTD->setInvalidDecl(); 3864 return NewTD; 3865} 3866 3867 3868/// \brief Determine whether a tag with a given kind is acceptable 3869/// as a redeclaration of the given tag declaration. 3870/// 3871/// \returns true if the new tag kind is acceptable, false otherwise. 3872bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3873 TagDecl::TagKind NewTag, 3874 SourceLocation NewTagLoc, 3875 const IdentifierInfo &Name) { 3876 // C++ [dcl.type.elab]p3: 3877 // The class-key or enum keyword present in the 3878 // elaborated-type-specifier shall agree in kind with the 3879 // declaration to which the name in theelaborated-type-specifier 3880 // refers. This rule also applies to the form of 3881 // elaborated-type-specifier that declares a class-name or 3882 // friend class since it can be construed as referring to the 3883 // definition of the class. Thus, in any 3884 // elaborated-type-specifier, the enum keyword shall be used to 3885 // refer to an enumeration (7.2), the union class-keyshall be 3886 // used to refer to a union (clause 9), and either the class or 3887 // struct class-key shall be used to refer to a class (clause 9) 3888 // declared using the class or struct class-key. 3889 TagDecl::TagKind OldTag = Previous->getTagKind(); 3890 if (OldTag == NewTag) 3891 return true; 3892 3893 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3894 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3895 // Warn about the struct/class tag mismatch. 3896 bool isTemplate = false; 3897 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3898 isTemplate = Record->getDescribedClassTemplate(); 3899 3900 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3901 << (NewTag == TagDecl::TK_class) 3902 << isTemplate << &Name 3903 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3904 OldTag == TagDecl::TK_class? "class" : "struct"); 3905 Diag(Previous->getLocation(), diag::note_previous_use); 3906 return true; 3907 } 3908 return false; 3909} 3910 3911/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3912/// former case, Name will be non-null. In the later case, Name will be null. 3913/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3914/// reference/declaration/definition of a tag. 3915Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3916 SourceLocation KWLoc, const CXXScopeSpec &SS, 3917 IdentifierInfo *Name, SourceLocation NameLoc, 3918 AttributeList *Attr, AccessSpecifier AS, 3919 MultiTemplateParamsArg TemplateParameterLists, 3920 bool &OwnedDecl) { 3921 // If this is not a definition, it must have a name. 3922 assert((Name != 0 || TUK == TUK_Definition) && 3923 "Nameless record must be a definition!"); 3924 3925 OwnedDecl = false; 3926 TagDecl::TagKind Kind; 3927 switch (TagSpec) { 3928 default: assert(0 && "Unknown tag type!"); 3929 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3930 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3931 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3932 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3933 } 3934 3935 if (TUK != TUK_Reference) { 3936 if (TemplateParameterList *TemplateParams 3937 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3938 (TemplateParameterList**)TemplateParameterLists.get(), 3939 TemplateParameterLists.size())) { 3940 if (TemplateParams->size() > 0) { 3941 // This is a declaration or definition of a class template (which may 3942 // be a member of another template). 3943 OwnedDecl = false; 3944 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 3945 SS, Name, NameLoc, Attr, 3946 move(TemplateParameterLists), 3947 AS); 3948 return Result.get(); 3949 } else { 3950 // FIXME: diagnose the extraneous 'template<>', once we recover 3951 // slightly better in ParseTemplate.cpp from bogus template 3952 // parameters. 3953 } 3954 } 3955 } 3956 3957 DeclContext *SearchDC = CurContext; 3958 DeclContext *DC = CurContext; 3959 NamedDecl *PrevDecl = 0; 3960 3961 bool Invalid = false; 3962 3963 if (Name && SS.isNotEmpty()) { 3964 // We have a nested-name tag ('struct foo::bar'). 3965 3966 // Check for invalid 'foo::'. 3967 if (SS.isInvalid()) { 3968 Name = 0; 3969 goto CreateNewDecl; 3970 } 3971 3972 if (RequireCompleteDeclContext(SS)) 3973 return DeclPtrTy::make((Decl *)0); 3974 3975 DC = computeDeclContext(SS, true); 3976 SearchDC = DC; 3977 // Look-up name inside 'foo::'. 3978 PrevDecl 3979 = dyn_cast_or_null<TagDecl>( 3980 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3981 3982 // A tag 'foo::bar' must already exist. 3983 if (PrevDecl == 0) { 3984 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3985 Name = 0; 3986 Invalid = true; 3987 goto CreateNewDecl; 3988 } 3989 } else if (Name) { 3990 // If this is a named struct, check to see if there was a previous forward 3991 // declaration or definition. 3992 // FIXME: We're looking into outer scopes here, even when we 3993 // shouldn't be. Doing so can result in ambiguities that we 3994 // shouldn't be diagnosing. 3995 LookupResult R = LookupName(S, Name, LookupTagName, 3996 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 3997 if (R.isAmbiguous()) { 3998 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3999 // FIXME: This is not best way to recover from case like: 4000 // 4001 // struct S s; 4002 // 4003 // causes needless "incomplete type" error later. 4004 Name = 0; 4005 PrevDecl = 0; 4006 Invalid = true; 4007 } else 4008 PrevDecl = R; 4009 4010 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4011 // FIXME: This makes sure that we ignore the contexts associated 4012 // with C structs, unions, and enums when looking for a matching 4013 // tag declaration or definition. See the similar lookup tweak 4014 // in Sema::LookupName; is there a better way to deal with this? 4015 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4016 SearchDC = SearchDC->getParent(); 4017 } 4018 } 4019 4020 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4021 // Maybe we will complain about the shadowed template parameter. 4022 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4023 // Just pretend that we didn't see the previous declaration. 4024 PrevDecl = 0; 4025 } 4026 4027 if (PrevDecl) { 4028 // Check whether the previous declaration is usable. 4029 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4030 4031 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4032 // If this is a use of a previous tag, or if the tag is already declared 4033 // in the same scope (so that the definition/declaration completes or 4034 // rementions the tag), reuse the decl. 4035 if (TUK == TUK_Reference || TUK == TUK_Friend || 4036 isDeclInScope(PrevDecl, SearchDC, S)) { 4037 // Make sure that this wasn't declared as an enum and now used as a 4038 // struct or something similar. 4039 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4040 bool SafeToContinue 4041 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4042 Kind != TagDecl::TK_enum); 4043 if (SafeToContinue) 4044 Diag(KWLoc, diag::err_use_with_wrong_tag) 4045 << Name 4046 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4047 PrevTagDecl->getKindName()); 4048 else 4049 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4050 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4051 4052 if (SafeToContinue) 4053 Kind = PrevTagDecl->getTagKind(); 4054 else { 4055 // Recover by making this an anonymous redefinition. 4056 Name = 0; 4057 PrevDecl = 0; 4058 Invalid = true; 4059 } 4060 } 4061 4062 if (!Invalid) { 4063 // If this is a use, just return the declaration we found. 4064 4065 // FIXME: In the future, return a variant or some other clue 4066 // for the consumer of this Decl to know it doesn't own it. 4067 // For our current ASTs this shouldn't be a problem, but will 4068 // need to be changed with DeclGroups. 4069 if (TUK == TUK_Reference) 4070 return DeclPtrTy::make(PrevDecl); 4071 4072 // If this is a friend, make sure we create the new 4073 // declaration in the appropriate semantic context. 4074 if (TUK == TUK_Friend) 4075 SearchDC = PrevDecl->getDeclContext(); 4076 4077 // Diagnose attempts to redefine a tag. 4078 if (TUK == TUK_Definition) { 4079 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4080 Diag(NameLoc, diag::err_redefinition) << Name; 4081 Diag(Def->getLocation(), diag::note_previous_definition); 4082 // If this is a redefinition, recover by making this 4083 // struct be anonymous, which will make any later 4084 // references get the previous definition. 4085 Name = 0; 4086 PrevDecl = 0; 4087 Invalid = true; 4088 } else { 4089 // If the type is currently being defined, complain 4090 // about a nested redefinition. 4091 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4092 if (Tag->isBeingDefined()) { 4093 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4094 Diag(PrevTagDecl->getLocation(), 4095 diag::note_previous_definition); 4096 Name = 0; 4097 PrevDecl = 0; 4098 Invalid = true; 4099 } 4100 } 4101 4102 // Okay, this is definition of a previously declared or referenced 4103 // tag PrevDecl. We're going to create a new Decl for it. 4104 } 4105 } 4106 // If we get here we have (another) forward declaration or we 4107 // have a definition. Just create a new decl. 4108 4109 } else { 4110 // If we get here, this is a definition of a new tag type in a nested 4111 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4112 // new decl/type. We set PrevDecl to NULL so that the entities 4113 // have distinct types. 4114 PrevDecl = 0; 4115 } 4116 // If we get here, we're going to create a new Decl. If PrevDecl 4117 // is non-NULL, it's a definition of the tag declared by 4118 // PrevDecl. If it's NULL, we have a new definition. 4119 } else { 4120 // PrevDecl is a namespace, template, or anything else 4121 // that lives in the IDNS_Tag identifier namespace. 4122 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4123 // The tag name clashes with a namespace name, issue an error and 4124 // recover by making this tag be anonymous. 4125 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4126 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4127 Name = 0; 4128 PrevDecl = 0; 4129 Invalid = true; 4130 } else { 4131 // The existing declaration isn't relevant to us; we're in a 4132 // new scope, so clear out the previous declaration. 4133 PrevDecl = 0; 4134 } 4135 } 4136 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4137 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4138 // C++ [basic.scope.pdecl]p5: 4139 // -- for an elaborated-type-specifier of the form 4140 // 4141 // class-key identifier 4142 // 4143 // if the elaborated-type-specifier is used in the 4144 // decl-specifier-seq or parameter-declaration-clause of a 4145 // function defined in namespace scope, the identifier is 4146 // declared as a class-name in the namespace that contains 4147 // the declaration; otherwise, except as a friend 4148 // declaration, the identifier is declared in the smallest 4149 // non-class, non-function-prototype scope that contains the 4150 // declaration. 4151 // 4152 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4153 // C structs and unions. 4154 // 4155 // GNU C also supports this behavior as part of its incomplete 4156 // enum types extension, while GNU C++ does not. 4157 // 4158 // Find the context where we'll be declaring the tag. 4159 // FIXME: We would like to maintain the current DeclContext as the 4160 // lexical context, 4161 while (SearchDC->isRecord()) 4162 SearchDC = SearchDC->getParent(); 4163 4164 // Find the scope where we'll be declaring the tag. 4165 while (S->isClassScope() || 4166 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4167 ((S->getFlags() & Scope::DeclScope) == 0) || 4168 (S->getEntity() && 4169 ((DeclContext *)S->getEntity())->isTransparentContext())) 4170 S = S->getParent(); 4171 4172 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4173 // C++ [namespace.memdef]p3: 4174 // If a friend declaration in a non-local class first declares a 4175 // class or function, the friend class or function is a member of 4176 // the innermost enclosing namespace. 4177 while (!SearchDC->isFileContext()) 4178 SearchDC = SearchDC->getParent(); 4179 4180 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4181 while (S->getEntity() != SearchDC) 4182 S = S->getParent(); 4183 } 4184 4185CreateNewDecl: 4186 4187 // If there is an identifier, use the location of the identifier as the 4188 // location of the decl, otherwise use the location of the struct/union 4189 // keyword. 4190 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4191 4192 // Otherwise, create a new declaration. If there is a previous 4193 // declaration of the same entity, the two will be linked via 4194 // PrevDecl. 4195 TagDecl *New; 4196 4197 if (Kind == TagDecl::TK_enum) { 4198 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4199 // enum X { A, B, C } D; D should chain to X. 4200 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4201 cast_or_null<EnumDecl>(PrevDecl)); 4202 // If this is an undefined enum, warn. 4203 if (TUK != TUK_Definition && !Invalid) { 4204 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4205 : diag::ext_forward_ref_enum; 4206 Diag(Loc, DK); 4207 } 4208 } else { 4209 // struct/union/class 4210 4211 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4212 // struct X { int A; } D; D should chain to X. 4213 if (getLangOptions().CPlusPlus) 4214 // FIXME: Look for a way to use RecordDecl for simple structs. 4215 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4216 cast_or_null<CXXRecordDecl>(PrevDecl)); 4217 else 4218 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4219 cast_or_null<RecordDecl>(PrevDecl)); 4220 } 4221 4222 if (Kind != TagDecl::TK_enum) { 4223 // Handle #pragma pack: if the #pragma pack stack has non-default 4224 // alignment, make up a packed attribute for this decl. These 4225 // attributes are checked when the ASTContext lays out the 4226 // structure. 4227 // 4228 // It is important for implementing the correct semantics that this 4229 // happen here (in act on tag decl). The #pragma pack stack is 4230 // maintained as a result of parser callbacks which can occur at 4231 // many points during the parsing of a struct declaration (because 4232 // the #pragma tokens are effectively skipped over during the 4233 // parsing of the struct). 4234 if (unsigned Alignment = getPragmaPackAlignment()) 4235 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4236 } 4237 4238 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4239 // C++ [dcl.typedef]p3: 4240 // [...] Similarly, in a given scope, a class or enumeration 4241 // shall not be declared with the same name as a typedef-name 4242 // that is declared in that scope and refers to a type other 4243 // than the class or enumeration itself. 4244 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4245 TypedefDecl *PrevTypedef = 0; 4246 if (Lookup.getKind() == LookupResult::Found) 4247 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4248 4249 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4250 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4251 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4252 Diag(Loc, diag::err_tag_definition_of_typedef) 4253 << Context.getTypeDeclType(New) 4254 << PrevTypedef->getUnderlyingType(); 4255 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4256 Invalid = true; 4257 } 4258 } 4259 4260 if (Invalid) 4261 New->setInvalidDecl(); 4262 4263 if (Attr) 4264 ProcessDeclAttributeList(S, New, Attr); 4265 4266 // If we're declaring or defining a tag in function prototype scope 4267 // in C, note that this type can only be used within the function. 4268 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4269 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4270 4271 // Set the lexical context. If the tag has a C++ scope specifier, the 4272 // lexical context will be different from the semantic context. 4273 New->setLexicalDeclContext(CurContext); 4274 4275 // Set the access specifier. 4276 if (!Invalid && TUK != TUK_Friend) 4277 SetMemberAccessSpecifier(New, PrevDecl, AS); 4278 4279 if (TUK == TUK_Definition) 4280 New->startDefinition(); 4281 4282 // If this has an identifier, add it to the scope stack. 4283 if (Name && TUK != TUK_Friend) { 4284 S = getNonFieldDeclScope(S); 4285 PushOnScopeChains(New, S); 4286 } else { 4287 CurContext->addDecl(New); 4288 } 4289 4290 // If this is the C FILE type, notify the AST context. 4291 if (IdentifierInfo *II = New->getIdentifier()) 4292 if (!New->isInvalidDecl() && 4293 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4294 II->isStr("FILE")) 4295 Context.setFILEDecl(New); 4296 4297 OwnedDecl = true; 4298 return DeclPtrTy::make(New); 4299} 4300 4301void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4302 AdjustDeclIfTemplate(TagD); 4303 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4304 4305 // Enter the tag context. 4306 PushDeclContext(S, Tag); 4307 4308 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4309 FieldCollector->StartClass(); 4310 4311 if (Record->getIdentifier()) { 4312 // C++ [class]p2: 4313 // [...] The class-name is also inserted into the scope of the 4314 // class itself; this is known as the injected-class-name. For 4315 // purposes of access checking, the injected-class-name is treated 4316 // as if it were a public member name. 4317 CXXRecordDecl *InjectedClassName 4318 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4319 CurContext, Record->getLocation(), 4320 Record->getIdentifier(), 4321 Record->getTagKeywordLoc(), 4322 Record); 4323 InjectedClassName->setImplicit(); 4324 InjectedClassName->setAccess(AS_public); 4325 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4326 InjectedClassName->setDescribedClassTemplate(Template); 4327 PushOnScopeChains(InjectedClassName, S); 4328 assert(InjectedClassName->isInjectedClassName() && 4329 "Broken injected-class-name"); 4330 } 4331 } 4332} 4333 4334void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4335 SourceLocation RBraceLoc) { 4336 AdjustDeclIfTemplate(TagD); 4337 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4338 Tag->setRBraceLoc(RBraceLoc); 4339 4340 if (isa<CXXRecordDecl>(Tag)) 4341 FieldCollector->FinishClass(); 4342 4343 // Exit this scope of this tag's definition. 4344 PopDeclContext(); 4345 4346 // Notify the consumer that we've defined a tag. 4347 Consumer.HandleTagDeclDefinition(Tag); 4348} 4349 4350// Note that FieldName may be null for anonymous bitfields. 4351bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4352 QualType FieldTy, const Expr *BitWidth, 4353 bool *ZeroWidth) { 4354 // Default to true; that shouldn't confuse checks for emptiness 4355 if (ZeroWidth) 4356 *ZeroWidth = true; 4357 4358 // C99 6.7.2.1p4 - verify the field type. 4359 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4360 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4361 // Handle incomplete types with specific error. 4362 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4363 return true; 4364 if (FieldName) 4365 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4366 << FieldName << FieldTy << BitWidth->getSourceRange(); 4367 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4368 << FieldTy << BitWidth->getSourceRange(); 4369 } 4370 4371 // If the bit-width is type- or value-dependent, don't try to check 4372 // it now. 4373 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4374 return false; 4375 4376 llvm::APSInt Value; 4377 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4378 return true; 4379 4380 if (Value != 0 && ZeroWidth) 4381 *ZeroWidth = false; 4382 4383 // Zero-width bitfield is ok for anonymous field. 4384 if (Value == 0 && FieldName) 4385 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4386 4387 if (Value.isSigned() && Value.isNegative()) { 4388 if (FieldName) 4389 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4390 << FieldName << Value.toString(10); 4391 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4392 << Value.toString(10); 4393 } 4394 4395 if (!FieldTy->isDependentType()) { 4396 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4397 if (Value.getZExtValue() > TypeSize) { 4398 if (FieldName) 4399 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4400 << FieldName << (unsigned)TypeSize; 4401 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4402 << (unsigned)TypeSize; 4403 } 4404 } 4405 4406 return false; 4407} 4408 4409/// ActOnField - Each field of a struct/union/class is passed into this in order 4410/// to create a FieldDecl object for it. 4411Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4412 SourceLocation DeclStart, 4413 Declarator &D, ExprTy *BitfieldWidth) { 4414 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4415 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4416 AS_public); 4417 return DeclPtrTy::make(Res); 4418} 4419 4420/// HandleField - Analyze a field of a C struct or a C++ data member. 4421/// 4422FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4423 SourceLocation DeclStart, 4424 Declarator &D, Expr *BitWidth, 4425 AccessSpecifier AS) { 4426 IdentifierInfo *II = D.getIdentifier(); 4427 SourceLocation Loc = DeclStart; 4428 if (II) Loc = D.getIdentifierLoc(); 4429 4430 DeclaratorInfo *DInfo = 0; 4431 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4432 if (getLangOptions().CPlusPlus) 4433 CheckExtraCXXDefaultArguments(D); 4434 4435 DiagnoseFunctionSpecifiers(D); 4436 4437 if (D.getDeclSpec().isThreadSpecified()) 4438 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4439 4440 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4441 4442 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4443 // Maybe we will complain about the shadowed template parameter. 4444 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4445 // Just pretend that we didn't see the previous declaration. 4446 PrevDecl = 0; 4447 } 4448 4449 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4450 PrevDecl = 0; 4451 4452 bool Mutable 4453 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4454 SourceLocation TSSL = D.getSourceRange().getBegin(); 4455 FieldDecl *NewFD 4456 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4457 AS, PrevDecl, &D); 4458 if (NewFD->isInvalidDecl() && PrevDecl) { 4459 // Don't introduce NewFD into scope; there's already something 4460 // with the same name in the same scope. 4461 } else if (II) { 4462 PushOnScopeChains(NewFD, S); 4463 } else 4464 Record->addDecl(NewFD); 4465 4466 return NewFD; 4467} 4468 4469/// \brief Build a new FieldDecl and check its well-formedness. 4470/// 4471/// This routine builds a new FieldDecl given the fields name, type, 4472/// record, etc. \p PrevDecl should refer to any previous declaration 4473/// with the same name and in the same scope as the field to be 4474/// created. 4475/// 4476/// \returns a new FieldDecl. 4477/// 4478/// \todo The Declarator argument is a hack. It will be removed once 4479FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4480 DeclaratorInfo *DInfo, 4481 RecordDecl *Record, SourceLocation Loc, 4482 bool Mutable, Expr *BitWidth, 4483 SourceLocation TSSL, 4484 AccessSpecifier AS, NamedDecl *PrevDecl, 4485 Declarator *D) { 4486 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4487 bool InvalidDecl = false; 4488 if (D) InvalidDecl = D->isInvalidType(); 4489 4490 // If we receive a broken type, recover by assuming 'int' and 4491 // marking this declaration as invalid. 4492 if (T.isNull()) { 4493 InvalidDecl = true; 4494 T = Context.IntTy; 4495 } 4496 4497 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4498 // than a variably modified type. 4499 if (T->isVariablyModifiedType()) { 4500 bool SizeIsNegative; 4501 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4502 SizeIsNegative); 4503 if (!FixedTy.isNull()) { 4504 Diag(Loc, diag::warn_illegal_constant_array_size); 4505 T = FixedTy; 4506 } else { 4507 if (SizeIsNegative) 4508 Diag(Loc, diag::err_typecheck_negative_array_size); 4509 else 4510 Diag(Loc, diag::err_typecheck_field_variable_size); 4511 InvalidDecl = true; 4512 } 4513 } 4514 4515 // Fields can not have abstract class types 4516 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4517 AbstractFieldType)) 4518 InvalidDecl = true; 4519 4520 bool ZeroWidth = false; 4521 // If this is declared as a bit-field, check the bit-field. 4522 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4523 InvalidDecl = true; 4524 DeleteExpr(BitWidth); 4525 BitWidth = 0; 4526 ZeroWidth = false; 4527 } 4528 4529 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4530 BitWidth, Mutable); 4531 if (InvalidDecl) 4532 NewFD->setInvalidDecl(); 4533 4534 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4535 Diag(Loc, diag::err_duplicate_member) << II; 4536 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4537 NewFD->setInvalidDecl(); 4538 } 4539 4540 if (getLangOptions().CPlusPlus) { 4541 QualType EltTy = Context.getBaseElementType(T); 4542 4543 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4544 4545 if (!T->isPODType()) 4546 CXXRecord->setPOD(false); 4547 if (!ZeroWidth) 4548 CXXRecord->setEmpty(false); 4549 4550 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4551 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4552 4553 if (!RDecl->hasTrivialConstructor()) 4554 CXXRecord->setHasTrivialConstructor(false); 4555 if (!RDecl->hasTrivialCopyConstructor()) 4556 CXXRecord->setHasTrivialCopyConstructor(false); 4557 if (!RDecl->hasTrivialCopyAssignment()) 4558 CXXRecord->setHasTrivialCopyAssignment(false); 4559 if (!RDecl->hasTrivialDestructor()) 4560 CXXRecord->setHasTrivialDestructor(false); 4561 4562 // C++ 9.5p1: An object of a class with a non-trivial 4563 // constructor, a non-trivial copy constructor, a non-trivial 4564 // destructor, or a non-trivial copy assignment operator 4565 // cannot be a member of a union, nor can an array of such 4566 // objects. 4567 // TODO: C++0x alters this restriction significantly. 4568 if (Record->isUnion()) { 4569 // We check for copy constructors before constructors 4570 // because otherwise we'll never get complaints about 4571 // copy constructors. 4572 4573 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4574 4575 CXXSpecialMember member; 4576 if (!RDecl->hasTrivialCopyConstructor()) 4577 member = CXXCopyConstructor; 4578 else if (!RDecl->hasTrivialConstructor()) 4579 member = CXXDefaultConstructor; 4580 else if (!RDecl->hasTrivialCopyAssignment()) 4581 member = CXXCopyAssignment; 4582 else if (!RDecl->hasTrivialDestructor()) 4583 member = CXXDestructor; 4584 else 4585 member = invalid; 4586 4587 if (member != invalid) { 4588 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4589 DiagnoseNontrivial(RT, member); 4590 NewFD->setInvalidDecl(); 4591 } 4592 } 4593 } 4594 } 4595 4596 // FIXME: We need to pass in the attributes given an AST 4597 // representation, not a parser representation. 4598 if (D) 4599 // FIXME: What to pass instead of TUScope? 4600 ProcessDeclAttributes(TUScope, NewFD, *D); 4601 4602 if (T.isObjCGCWeak()) 4603 Diag(Loc, diag::warn_attribute_weak_on_field); 4604 4605 NewFD->setAccess(AS); 4606 4607 // C++ [dcl.init.aggr]p1: 4608 // An aggregate is an array or a class (clause 9) with [...] no 4609 // private or protected non-static data members (clause 11). 4610 // A POD must be an aggregate. 4611 if (getLangOptions().CPlusPlus && 4612 (AS == AS_private || AS == AS_protected)) { 4613 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4614 CXXRecord->setAggregate(false); 4615 CXXRecord->setPOD(false); 4616 } 4617 4618 return NewFD; 4619} 4620 4621/// DiagnoseNontrivial - Given that a class has a non-trivial 4622/// special member, figure out why. 4623void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4624 QualType QT(T, 0U); 4625 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4626 4627 // Check whether the member was user-declared. 4628 switch (member) { 4629 case CXXDefaultConstructor: 4630 if (RD->hasUserDeclaredConstructor()) { 4631 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4632 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4633 if (!ci->isImplicitlyDefined(Context)) { 4634 SourceLocation CtorLoc = ci->getLocation(); 4635 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4636 return; 4637 } 4638 4639 assert(0 && "found no user-declared constructors"); 4640 return; 4641 } 4642 break; 4643 4644 case CXXCopyConstructor: 4645 if (RD->hasUserDeclaredCopyConstructor()) { 4646 SourceLocation CtorLoc = 4647 RD->getCopyConstructor(Context, 0)->getLocation(); 4648 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4649 return; 4650 } 4651 break; 4652 4653 case CXXCopyAssignment: 4654 if (RD->hasUserDeclaredCopyAssignment()) { 4655 // FIXME: this should use the location of the copy 4656 // assignment, not the type. 4657 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4658 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4659 return; 4660 } 4661 break; 4662 4663 case CXXDestructor: 4664 if (RD->hasUserDeclaredDestructor()) { 4665 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4666 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4667 return; 4668 } 4669 break; 4670 } 4671 4672 typedef CXXRecordDecl::base_class_iterator base_iter; 4673 4674 // Virtual bases and members inhibit trivial copying/construction, 4675 // but not trivial destruction. 4676 if (member != CXXDestructor) { 4677 // Check for virtual bases. vbases includes indirect virtual bases, 4678 // so we just iterate through the direct bases. 4679 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4680 if (bi->isVirtual()) { 4681 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4682 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4683 return; 4684 } 4685 4686 // Check for virtual methods. 4687 typedef CXXRecordDecl::method_iterator meth_iter; 4688 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4689 ++mi) { 4690 if (mi->isVirtual()) { 4691 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4692 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4693 return; 4694 } 4695 } 4696 } 4697 4698 bool (CXXRecordDecl::*hasTrivial)() const; 4699 switch (member) { 4700 case CXXDefaultConstructor: 4701 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4702 case CXXCopyConstructor: 4703 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4704 case CXXCopyAssignment: 4705 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4706 case CXXDestructor: 4707 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4708 default: 4709 assert(0 && "unexpected special member"); return; 4710 } 4711 4712 // Check for nontrivial bases (and recurse). 4713 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4714 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4715 assert(BaseRT); 4716 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4717 if (!(BaseRecTy->*hasTrivial)()) { 4718 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4719 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4720 DiagnoseNontrivial(BaseRT, member); 4721 return; 4722 } 4723 } 4724 4725 // Check for nontrivial members (and recurse). 4726 typedef RecordDecl::field_iterator field_iter; 4727 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4728 ++fi) { 4729 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4730 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4731 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4732 4733 if (!(EltRD->*hasTrivial)()) { 4734 SourceLocation FLoc = (*fi)->getLocation(); 4735 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4736 DiagnoseNontrivial(EltRT, member); 4737 return; 4738 } 4739 } 4740 } 4741 4742 assert(0 && "found no explanation for non-trivial member"); 4743} 4744 4745/// TranslateIvarVisibility - Translate visibility from a token ID to an 4746/// AST enum value. 4747static ObjCIvarDecl::AccessControl 4748TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4749 switch (ivarVisibility) { 4750 default: assert(0 && "Unknown visitibility kind"); 4751 case tok::objc_private: return ObjCIvarDecl::Private; 4752 case tok::objc_public: return ObjCIvarDecl::Public; 4753 case tok::objc_protected: return ObjCIvarDecl::Protected; 4754 case tok::objc_package: return ObjCIvarDecl::Package; 4755 } 4756} 4757 4758/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4759/// in order to create an IvarDecl object for it. 4760Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4761 SourceLocation DeclStart, 4762 DeclPtrTy IntfDecl, 4763 Declarator &D, ExprTy *BitfieldWidth, 4764 tok::ObjCKeywordKind Visibility) { 4765 4766 IdentifierInfo *II = D.getIdentifier(); 4767 Expr *BitWidth = (Expr*)BitfieldWidth; 4768 SourceLocation Loc = DeclStart; 4769 if (II) Loc = D.getIdentifierLoc(); 4770 4771 // FIXME: Unnamed fields can be handled in various different ways, for 4772 // example, unnamed unions inject all members into the struct namespace! 4773 4774 DeclaratorInfo *DInfo = 0; 4775 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4776 4777 if (BitWidth) { 4778 // 6.7.2.1p3, 6.7.2.1p4 4779 if (VerifyBitField(Loc, II, T, BitWidth)) { 4780 D.setInvalidType(); 4781 DeleteExpr(BitWidth); 4782 BitWidth = 0; 4783 } 4784 } else { 4785 // Not a bitfield. 4786 4787 // validate II. 4788 4789 } 4790 4791 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4792 // than a variably modified type. 4793 if (T->isVariablyModifiedType()) { 4794 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4795 D.setInvalidType(); 4796 } 4797 4798 // Get the visibility (access control) for this ivar. 4799 ObjCIvarDecl::AccessControl ac = 4800 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4801 : ObjCIvarDecl::None; 4802 // Must set ivar's DeclContext to its enclosing interface. 4803 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4804 DeclContext *EnclosingContext; 4805 if (ObjCImplementationDecl *IMPDecl = 4806 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4807 // Case of ivar declared in an implementation. Context is that of its class. 4808 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4809 assert(IDecl && "No class- ActOnIvar"); 4810 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4811 } else 4812 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4813 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4814 4815 // Construct the decl. 4816 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4817 EnclosingContext, Loc, II, T, 4818 DInfo, ac, (Expr *)BitfieldWidth); 4819 4820 if (II) { 4821 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4822 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4823 && !isa<TagDecl>(PrevDecl)) { 4824 Diag(Loc, diag::err_duplicate_member) << II; 4825 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4826 NewID->setInvalidDecl(); 4827 } 4828 } 4829 4830 // Process attributes attached to the ivar. 4831 ProcessDeclAttributes(S, NewID, D); 4832 4833 if (D.isInvalidType()) 4834 NewID->setInvalidDecl(); 4835 4836 if (II) { 4837 // FIXME: When interfaces are DeclContexts, we'll need to add 4838 // these to the interface. 4839 S->AddDecl(DeclPtrTy::make(NewID)); 4840 IdResolver.AddDecl(NewID); 4841 } 4842 4843 return DeclPtrTy::make(NewID); 4844} 4845 4846void Sema::ActOnFields(Scope* S, 4847 SourceLocation RecLoc, DeclPtrTy RecDecl, 4848 DeclPtrTy *Fields, unsigned NumFields, 4849 SourceLocation LBrac, SourceLocation RBrac, 4850 AttributeList *Attr) { 4851 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4852 assert(EnclosingDecl && "missing record or interface decl"); 4853 4854 // If the decl this is being inserted into is invalid, then it may be a 4855 // redeclaration or some other bogus case. Don't try to add fields to it. 4856 if (EnclosingDecl->isInvalidDecl()) { 4857 // FIXME: Deallocate fields? 4858 return; 4859 } 4860 4861 4862 // Verify that all the fields are okay. 4863 unsigned NumNamedMembers = 0; 4864 llvm::SmallVector<FieldDecl*, 32> RecFields; 4865 4866 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4867 for (unsigned i = 0; i != NumFields; ++i) { 4868 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4869 4870 // Get the type for the field. 4871 Type *FDTy = FD->getType().getTypePtr(); 4872 4873 if (!FD->isAnonymousStructOrUnion()) { 4874 // Remember all fields written by the user. 4875 RecFields.push_back(FD); 4876 } 4877 4878 // If the field is already invalid for some reason, don't emit more 4879 // diagnostics about it. 4880 if (FD->isInvalidDecl()) 4881 continue; 4882 4883 // C99 6.7.2.1p2: 4884 // A structure or union shall not contain a member with 4885 // incomplete or function type (hence, a structure shall not 4886 // contain an instance of itself, but may contain a pointer to 4887 // an instance of itself), except that the last member of a 4888 // structure with more than one named member may have incomplete 4889 // array type; such a structure (and any union containing, 4890 // possibly recursively, a member that is such a structure) 4891 // shall not be a member of a structure or an element of an 4892 // array. 4893 if (FDTy->isFunctionType()) { 4894 // Field declared as a function. 4895 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4896 << FD->getDeclName(); 4897 FD->setInvalidDecl(); 4898 EnclosingDecl->setInvalidDecl(); 4899 continue; 4900 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4901 Record && Record->isStruct()) { 4902 // Flexible array member. 4903 if (NumNamedMembers < 1) { 4904 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4905 << FD->getDeclName(); 4906 FD->setInvalidDecl(); 4907 EnclosingDecl->setInvalidDecl(); 4908 continue; 4909 } 4910 // Okay, we have a legal flexible array member at the end of the struct. 4911 if (Record) 4912 Record->setHasFlexibleArrayMember(true); 4913 } else if (!FDTy->isDependentType() && 4914 RequireCompleteType(FD->getLocation(), FD->getType(), 4915 diag::err_field_incomplete)) { 4916 // Incomplete type 4917 FD->setInvalidDecl(); 4918 EnclosingDecl->setInvalidDecl(); 4919 continue; 4920 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 4921 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4922 // If this is a member of a union, then entire union becomes "flexible". 4923 if (Record && Record->isUnion()) { 4924 Record->setHasFlexibleArrayMember(true); 4925 } else { 4926 // If this is a struct/class and this is not the last element, reject 4927 // it. Note that GCC supports variable sized arrays in the middle of 4928 // structures. 4929 if (i != NumFields-1) 4930 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4931 << FD->getDeclName() << FD->getType(); 4932 else { 4933 // We support flexible arrays at the end of structs in 4934 // other structs as an extension. 4935 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4936 << FD->getDeclName(); 4937 if (Record) 4938 Record->setHasFlexibleArrayMember(true); 4939 } 4940 } 4941 } 4942 if (Record && FDTTy->getDecl()->hasObjectMember()) 4943 Record->setHasObjectMember(true); 4944 } else if (FDTy->isObjCInterfaceType()) { 4945 /// A field cannot be an Objective-c object 4946 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4947 FD->setInvalidDecl(); 4948 EnclosingDecl->setInvalidDecl(); 4949 continue; 4950 } else if (getLangOptions().ObjC1 && 4951 getLangOptions().getGCMode() != LangOptions::NonGC && 4952 Record && 4953 (FD->getType()->isObjCObjectPointerType() || 4954 FD->getType().isObjCGCStrong())) 4955 Record->setHasObjectMember(true); 4956 // Keep track of the number of named members. 4957 if (FD->getIdentifier()) 4958 ++NumNamedMembers; 4959 } 4960 4961 // Okay, we successfully defined 'Record'. 4962 if (Record) { 4963 Record->completeDefinition(Context); 4964 } else { 4965 ObjCIvarDecl **ClsFields = 4966 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4967 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4968 ID->setIVarList(ClsFields, RecFields.size(), Context); 4969 ID->setLocEnd(RBrac); 4970 // Add ivar's to class's DeclContext. 4971 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4972 ClsFields[i]->setLexicalDeclContext(ID); 4973 ID->addDecl(ClsFields[i]); 4974 } 4975 // Must enforce the rule that ivars in the base classes may not be 4976 // duplicates. 4977 if (ID->getSuperClass()) { 4978 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4979 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4980 ObjCIvarDecl* Ivar = (*IVI); 4981 4982 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4983 ObjCIvarDecl* prevIvar = 4984 ID->getSuperClass()->lookupInstanceVariable(II); 4985 if (prevIvar) { 4986 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4987 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4988 } 4989 } 4990 } 4991 } 4992 } else if (ObjCImplementationDecl *IMPDecl = 4993 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4994 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4995 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4996 // Ivar declared in @implementation never belongs to the implementation. 4997 // Only it is in implementation's lexical context. 4998 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4999 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5000 } 5001 } 5002 5003 if (Attr) 5004 ProcessDeclAttributeList(S, Record, Attr); 5005} 5006 5007EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5008 EnumConstantDecl *LastEnumConst, 5009 SourceLocation IdLoc, 5010 IdentifierInfo *Id, 5011 ExprArg val) { 5012 Expr *Val = (Expr *)val.get(); 5013 5014 llvm::APSInt EnumVal(32); 5015 QualType EltTy; 5016 if (Val && !Val->isTypeDependent()) { 5017 // Make sure to promote the operand type to int. 5018 UsualUnaryConversions(Val); 5019 if (Val != val.get()) { 5020 val.release(); 5021 val = Val; 5022 } 5023 5024 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5025 SourceLocation ExpLoc; 5026 if (!Val->isValueDependent() && 5027 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5028 Val = 0; 5029 } else { 5030 EltTy = Val->getType(); 5031 } 5032 } 5033 5034 if (!Val) { 5035 if (LastEnumConst) { 5036 // Assign the last value + 1. 5037 EnumVal = LastEnumConst->getInitVal(); 5038 ++EnumVal; 5039 5040 // Check for overflow on increment. 5041 if (EnumVal < LastEnumConst->getInitVal()) 5042 Diag(IdLoc, diag::warn_enum_value_overflow); 5043 5044 EltTy = LastEnumConst->getType(); 5045 } else { 5046 // First value, set to zero. 5047 EltTy = Context.IntTy; 5048 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5049 } 5050 } 5051 5052 val.release(); 5053 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5054 Val, EnumVal); 5055} 5056 5057 5058Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5059 DeclPtrTy lastEnumConst, 5060 SourceLocation IdLoc, 5061 IdentifierInfo *Id, 5062 SourceLocation EqualLoc, ExprTy *val) { 5063 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5064 EnumConstantDecl *LastEnumConst = 5065 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5066 Expr *Val = static_cast<Expr*>(val); 5067 5068 // The scope passed in may not be a decl scope. Zip up the scope tree until 5069 // we find one that is. 5070 S = getNonFieldDeclScope(S); 5071 5072 // Verify that there isn't already something declared with this name in this 5073 // scope. 5074 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5075 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5076 // Maybe we will complain about the shadowed template parameter. 5077 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5078 // Just pretend that we didn't see the previous declaration. 5079 PrevDecl = 0; 5080 } 5081 5082 if (PrevDecl) { 5083 // When in C++, we may get a TagDecl with the same name; in this case the 5084 // enum constant will 'hide' the tag. 5085 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5086 "Received TagDecl when not in C++!"); 5087 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5088 if (isa<EnumConstantDecl>(PrevDecl)) 5089 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5090 else 5091 Diag(IdLoc, diag::err_redefinition) << Id; 5092 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5093 if (Val) Val->Destroy(Context); 5094 return DeclPtrTy(); 5095 } 5096 } 5097 5098 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5099 IdLoc, Id, Owned(Val)); 5100 5101 // Register this decl in the current scope stack. 5102 if (New) 5103 PushOnScopeChains(New, S); 5104 5105 return DeclPtrTy::make(New); 5106} 5107 5108void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5109 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5110 DeclPtrTy *Elements, unsigned NumElements, 5111 Scope *S, AttributeList *Attr) { 5112 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5113 QualType EnumType = Context.getTypeDeclType(Enum); 5114 5115 if (Attr) 5116 ProcessDeclAttributeList(S, Enum, Attr); 5117 5118 // TODO: If the result value doesn't fit in an int, it must be a long or long 5119 // long value. ISO C does not support this, but GCC does as an extension, 5120 // emit a warning. 5121 unsigned IntWidth = Context.Target.getIntWidth(); 5122 unsigned CharWidth = Context.Target.getCharWidth(); 5123 unsigned ShortWidth = Context.Target.getShortWidth(); 5124 5125 // Verify that all the values are okay, compute the size of the values, and 5126 // reverse the list. 5127 unsigned NumNegativeBits = 0; 5128 unsigned NumPositiveBits = 0; 5129 5130 // Keep track of whether all elements have type int. 5131 bool AllElementsInt = true; 5132 5133 for (unsigned i = 0; i != NumElements; ++i) { 5134 EnumConstantDecl *ECD = 5135 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5136 if (!ECD) continue; // Already issued a diagnostic. 5137 5138 // If the enum value doesn't fit in an int, emit an extension warning. 5139 const llvm::APSInt &InitVal = ECD->getInitVal(); 5140 assert(InitVal.getBitWidth() >= IntWidth && 5141 "Should have promoted value to int"); 5142 if (InitVal.getBitWidth() > IntWidth) { 5143 llvm::APSInt V(InitVal); 5144 V.trunc(IntWidth); 5145 V.extend(InitVal.getBitWidth()); 5146 if (V != InitVal) 5147 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5148 << InitVal.toString(10); 5149 } 5150 5151 // Keep track of the size of positive and negative values. 5152 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5153 NumPositiveBits = std::max(NumPositiveBits, 5154 (unsigned)InitVal.getActiveBits()); 5155 else 5156 NumNegativeBits = std::max(NumNegativeBits, 5157 (unsigned)InitVal.getMinSignedBits()); 5158 5159 // Keep track of whether every enum element has type int (very commmon). 5160 if (AllElementsInt) 5161 AllElementsInt = ECD->getType() == Context.IntTy; 5162 } 5163 5164 // Figure out the type that should be used for this enum. 5165 // FIXME: Support -fshort-enums. 5166 QualType BestType; 5167 unsigned BestWidth; 5168 5169 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5170 5171 if (NumNegativeBits) { 5172 // If there is a negative value, figure out the smallest integer type (of 5173 // int/long/longlong) that fits. 5174 // If it's packed, check also if it fits a char or a short. 5175 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5176 BestType = Context.SignedCharTy; 5177 BestWidth = CharWidth; 5178 } else if (Packed && NumNegativeBits <= ShortWidth && 5179 NumPositiveBits < ShortWidth) { 5180 BestType = Context.ShortTy; 5181 BestWidth = ShortWidth; 5182 } 5183 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5184 BestType = Context.IntTy; 5185 BestWidth = IntWidth; 5186 } else { 5187 BestWidth = Context.Target.getLongWidth(); 5188 5189 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5190 BestType = Context.LongTy; 5191 else { 5192 BestWidth = Context.Target.getLongLongWidth(); 5193 5194 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5195 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5196 BestType = Context.LongLongTy; 5197 } 5198 } 5199 } else { 5200 // If there is no negative value, figure out which of uint, ulong, ulonglong 5201 // fits. 5202 // If it's packed, check also if it fits a char or a short. 5203 if (Packed && NumPositiveBits <= CharWidth) { 5204 BestType = Context.UnsignedCharTy; 5205 BestWidth = CharWidth; 5206 } else if (Packed && NumPositiveBits <= ShortWidth) { 5207 BestType = Context.UnsignedShortTy; 5208 BestWidth = ShortWidth; 5209 } 5210 else if (NumPositiveBits <= IntWidth) { 5211 BestType = Context.UnsignedIntTy; 5212 BestWidth = IntWidth; 5213 } else if (NumPositiveBits <= 5214 (BestWidth = Context.Target.getLongWidth())) { 5215 BestType = Context.UnsignedLongTy; 5216 } else { 5217 BestWidth = Context.Target.getLongLongWidth(); 5218 assert(NumPositiveBits <= BestWidth && 5219 "How could an initializer get larger than ULL?"); 5220 BestType = Context.UnsignedLongLongTy; 5221 } 5222 } 5223 5224 // Loop over all of the enumerator constants, changing their types to match 5225 // the type of the enum if needed. 5226 for (unsigned i = 0; i != NumElements; ++i) { 5227 EnumConstantDecl *ECD = 5228 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5229 if (!ECD) continue; // Already issued a diagnostic. 5230 5231 // Standard C says the enumerators have int type, but we allow, as an 5232 // extension, the enumerators to be larger than int size. If each 5233 // enumerator value fits in an int, type it as an int, otherwise type it the 5234 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5235 // that X has type 'int', not 'unsigned'. 5236 if (ECD->getType() == Context.IntTy) { 5237 // Make sure the init value is signed. 5238 llvm::APSInt IV = ECD->getInitVal(); 5239 IV.setIsSigned(true); 5240 ECD->setInitVal(IV); 5241 5242 if (getLangOptions().CPlusPlus) 5243 // C++ [dcl.enum]p4: Following the closing brace of an 5244 // enum-specifier, each enumerator has the type of its 5245 // enumeration. 5246 ECD->setType(EnumType); 5247 continue; // Already int type. 5248 } 5249 5250 // Determine whether the value fits into an int. 5251 llvm::APSInt InitVal = ECD->getInitVal(); 5252 bool FitsInInt; 5253 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5254 FitsInInt = InitVal.getActiveBits() < IntWidth; 5255 else 5256 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5257 5258 // If it fits into an integer type, force it. Otherwise force it to match 5259 // the enum decl type. 5260 QualType NewTy; 5261 unsigned NewWidth; 5262 bool NewSign; 5263 if (FitsInInt) { 5264 NewTy = Context.IntTy; 5265 NewWidth = IntWidth; 5266 NewSign = true; 5267 } else if (ECD->getType() == BestType) { 5268 // Already the right type! 5269 if (getLangOptions().CPlusPlus) 5270 // C++ [dcl.enum]p4: Following the closing brace of an 5271 // enum-specifier, each enumerator has the type of its 5272 // enumeration. 5273 ECD->setType(EnumType); 5274 continue; 5275 } else { 5276 NewTy = BestType; 5277 NewWidth = BestWidth; 5278 NewSign = BestType->isSignedIntegerType(); 5279 } 5280 5281 // Adjust the APSInt value. 5282 InitVal.extOrTrunc(NewWidth); 5283 InitVal.setIsSigned(NewSign); 5284 ECD->setInitVal(InitVal); 5285 5286 // Adjust the Expr initializer and type. 5287 if (ECD->getInitExpr()) 5288 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5289 CastExpr::CK_Unknown, 5290 ECD->getInitExpr(), 5291 /*isLvalue=*/false)); 5292 if (getLangOptions().CPlusPlus) 5293 // C++ [dcl.enum]p4: Following the closing brace of an 5294 // enum-specifier, each enumerator has the type of its 5295 // enumeration. 5296 ECD->setType(EnumType); 5297 else 5298 ECD->setType(NewTy); 5299 } 5300 5301 Enum->completeDefinition(Context, BestType); 5302} 5303 5304Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5305 ExprArg expr) { 5306 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5307 5308 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5309 Loc, AsmString); 5310 CurContext->addDecl(New); 5311 return DeclPtrTy::make(New); 5312} 5313 5314void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5315 SourceLocation PragmaLoc, 5316 SourceLocation NameLoc) { 5317 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5318 5319 if (PrevDecl) { 5320 PrevDecl->addAttr(::new (Context) WeakAttr()); 5321 } else { 5322 (void)WeakUndeclaredIdentifiers.insert( 5323 std::pair<IdentifierInfo*,WeakInfo> 5324 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5325 } 5326} 5327 5328void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5329 IdentifierInfo* AliasName, 5330 SourceLocation PragmaLoc, 5331 SourceLocation NameLoc, 5332 SourceLocation AliasNameLoc) { 5333 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5334 WeakInfo W = WeakInfo(Name, NameLoc); 5335 5336 if (PrevDecl) { 5337 if (!PrevDecl->hasAttr<AliasAttr>()) 5338 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5339 DeclApplyPragmaWeak(TUScope, ND, W); 5340 } else { 5341 (void)WeakUndeclaredIdentifiers.insert( 5342 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5343 } 5344} 5345