SemaDecl.cpp revision 16f19306f9dd24cdc397ceae89a73a55086e5127
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/DeclObjC.h" 20#include "clang/AST/DeclTemplate.h" 21#include "clang/AST/ExprCXX.h" 22#include "clang/AST/StmtCXX.h" 23#include "clang/Parse/DeclSpec.h" 24#include "clang/Basic/TargetInfo.h" 25#include "clang/Basic/SourceManager.h" 26// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 27#include "clang/Lex/Preprocessor.h" 28#include "clang/Lex/HeaderSearch.h" 29#include "llvm/ADT/SmallSet.h" 30#include "llvm/ADT/STLExtras.h" 31#include <algorithm> 32#include <functional> 33using namespace clang; 34 35/// getDeclName - Return a pretty name for the specified decl if possible, or 36/// an empty string if not. This is used for pretty crash reporting. 37std::string Sema::getDeclName(DeclPtrTy d) { 38 Decl *D = d.getAs<Decl>(); 39 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 40 return DN->getQualifiedNameAsString(); 41 return ""; 42} 43 44Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 45 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 46} 47 48/// \brief If the identifier refers to a type name within this scope, 49/// return the declaration of that type. 50/// 51/// This routine performs ordinary name lookup of the identifier II 52/// within the given scope, with optional C++ scope specifier SS, to 53/// determine whether the name refers to a type. If so, returns an 54/// opaque pointer (actually a QualType) corresponding to that 55/// type. Otherwise, returns NULL. 56/// 57/// If name lookup results in an ambiguity, this routine will complain 58/// and then return NULL. 59Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 60 Scope *S, const CXXScopeSpec *SS) { 61 // C++ [temp.res]p3: 62 // A qualified-id that refers to a type and in which the 63 // nested-name-specifier depends on a template-parameter (14.6.2) 64 // shall be prefixed by the keyword typename to indicate that the 65 // qualified-id denotes a type, forming an 66 // elaborated-type-specifier (7.1.5.3). 67 // 68 // We therefore do not perform any name lookup if the result would 69 // refer to a member of an unknown specialization. 70 if (SS && isUnknownSpecialization(*SS)) 71 return 0; 72 73 LookupResult Result 74 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 75 76 NamedDecl *IIDecl = 0; 77 switch (Result.getKind()) { 78 case LookupResult::NotFound: 79 case LookupResult::FoundOverloaded: 80 return 0; 81 82 case LookupResult::AmbiguousBaseSubobjectTypes: 83 case LookupResult::AmbiguousBaseSubobjects: 84 case LookupResult::AmbiguousReference: { 85 // Look to see if we have a type anywhere in the list of results. 86 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 87 Res != ResEnd; ++Res) { 88 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 89 if (!IIDecl || 90 (*Res)->getLocation().getRawEncoding() < 91 IIDecl->getLocation().getRawEncoding()) 92 IIDecl = *Res; 93 } 94 } 95 96 if (!IIDecl) { 97 // None of the entities we found is a type, so there is no way 98 // to even assume that the result is a type. In this case, don't 99 // complain about the ambiguity. The parser will either try to 100 // perform this lookup again (e.g., as an object name), which 101 // will produce the ambiguity, or will complain that it expected 102 // a type name. 103 Result.Destroy(); 104 return 0; 105 } 106 107 // We found a type within the ambiguous lookup; diagnose the 108 // ambiguity and then return that type. This might be the right 109 // answer, or it might not be, but it suppresses any attempt to 110 // perform the name lookup again. 111 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 112 break; 113 } 114 115 case LookupResult::Found: 116 IIDecl = Result.getAsDecl(); 117 break; 118 } 119 120 if (IIDecl) { 121 QualType T; 122 123 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 124 // Check whether we can use this type 125 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 126 127 if (getLangOptions().CPlusPlus) { 128 // C++ [temp.local]p2: 129 // Within the scope of a class template specialization or 130 // partial specialization, when the injected-class-name is 131 // not followed by a <, it is equivalent to the 132 // injected-class-name followed by the template-argument s 133 // of the class template specialization or partial 134 // specialization enclosed in <>. 135 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 136 if (RD->isInjectedClassName()) 137 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 138 T = Template->getInjectedClassNameType(Context); 139 } 140 141 if (T.isNull()) 142 T = Context.getTypeDeclType(TD); 143 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 144 // Check whether we can use this interface. 145 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 146 147 T = Context.getObjCInterfaceType(IDecl); 148 } else 149 return 0; 150 151 if (SS) 152 T = getQualifiedNameType(*SS, T); 153 154 return T.getAsOpaquePtr(); 155 } 156 157 return 0; 158} 159 160/// isTagName() - This method is called *for error recovery purposes only* 161/// to determine if the specified name is a valid tag name ("struct foo"). If 162/// so, this returns the TST for the tag corresponding to it (TST_enum, 163/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 164/// where the user forgot to specify the tag. 165DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 166 // Do a tag name lookup in this scope. 167 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 168 if (R.getKind() == LookupResult::Found) 169 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 170 switch (TD->getTagKind()) { 171 case TagDecl::TK_struct: return DeclSpec::TST_struct; 172 case TagDecl::TK_union: return DeclSpec::TST_union; 173 case TagDecl::TK_class: return DeclSpec::TST_class; 174 case TagDecl::TK_enum: return DeclSpec::TST_enum; 175 } 176 } 177 178 return DeclSpec::TST_unspecified; 179} 180 181 182 183DeclContext *Sema::getContainingDC(DeclContext *DC) { 184 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 185 // A C++ out-of-line method will return to the file declaration context. 186 if (MD->isOutOfLine()) 187 return MD->getLexicalDeclContext(); 188 189 // A C++ inline method is parsed *after* the topmost class it was declared 190 // in is fully parsed (it's "complete"). 191 // The parsing of a C++ inline method happens at the declaration context of 192 // the topmost (non-nested) class it is lexically declared in. 193 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 194 DC = MD->getParent(); 195 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 196 DC = RD; 197 198 // Return the declaration context of the topmost class the inline method is 199 // declared in. 200 return DC; 201 } 202 203 if (isa<ObjCMethodDecl>(DC)) 204 return Context.getTranslationUnitDecl(); 205 206 return DC->getLexicalParent(); 207} 208 209void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 210 assert(getContainingDC(DC) == CurContext && 211 "The next DeclContext should be lexically contained in the current one."); 212 CurContext = DC; 213 S->setEntity(DC); 214} 215 216void Sema::PopDeclContext() { 217 assert(CurContext && "DeclContext imbalance!"); 218 219 CurContext = getContainingDC(CurContext); 220} 221 222/// EnterDeclaratorContext - Used when we must lookup names in the context 223/// of a declarator's nested name specifier. 224void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 225 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 226 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 227 CurContext = DC; 228 assert(CurContext && "No context?"); 229 S->setEntity(CurContext); 230} 231 232void Sema::ExitDeclaratorContext(Scope *S) { 233 S->setEntity(PreDeclaratorDC); 234 PreDeclaratorDC = 0; 235 236 // Reset CurContext to the nearest enclosing context. 237 while (!S->getEntity() && S->getParent()) 238 S = S->getParent(); 239 CurContext = static_cast<DeclContext*>(S->getEntity()); 240 assert(CurContext && "No context?"); 241} 242 243/// \brief Determine whether we allow overloading of the function 244/// PrevDecl with another declaration. 245/// 246/// This routine determines whether overloading is possible, not 247/// whether some new function is actually an overload. It will return 248/// true in C++ (where we can always provide overloads) or, as an 249/// extension, in C when the previous function is already an 250/// overloaded function declaration or has the "overloadable" 251/// attribute. 252static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 253 if (Context.getLangOptions().CPlusPlus) 254 return true; 255 256 if (isa<OverloadedFunctionDecl>(PrevDecl)) 257 return true; 258 259 return PrevDecl->getAttr<OverloadableAttr>(Context) != 0; 260} 261 262/// Add this decl to the scope shadowed decl chains. 263void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 264 // Move up the scope chain until we find the nearest enclosing 265 // non-transparent context. The declaration will be introduced into this 266 // scope. 267 while (S->getEntity() && 268 ((DeclContext *)S->getEntity())->isTransparentContext()) 269 S = S->getParent(); 270 271 S->AddDecl(DeclPtrTy::make(D)); 272 273 // Add scoped declarations into their context, so that they can be 274 // found later. Declarations without a context won't be inserted 275 // into any context. 276 CurContext->addDecl(Context, D); 277 278 // C++ [basic.scope]p4: 279 // -- exactly one declaration shall declare a class name or 280 // enumeration name that is not a typedef name and the other 281 // declarations shall all refer to the same object or 282 // enumerator, or all refer to functions and function templates; 283 // in this case the class name or enumeration name is hidden. 284 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 285 // We are pushing the name of a tag (enum or class). 286 if (CurContext->getLookupContext() 287 == TD->getDeclContext()->getLookupContext()) { 288 // We're pushing the tag into the current context, which might 289 // require some reshuffling in the identifier resolver. 290 IdentifierResolver::iterator 291 I = IdResolver.begin(TD->getDeclName()), 292 IEnd = IdResolver.end(); 293 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 294 NamedDecl *PrevDecl = *I; 295 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 296 PrevDecl = *I, ++I) { 297 if (TD->declarationReplaces(*I)) { 298 // This is a redeclaration. Remove it from the chain and 299 // break out, so that we'll add in the shadowed 300 // declaration. 301 S->RemoveDecl(DeclPtrTy::make(*I)); 302 if (PrevDecl == *I) { 303 IdResolver.RemoveDecl(*I); 304 IdResolver.AddDecl(TD); 305 return; 306 } else { 307 IdResolver.RemoveDecl(*I); 308 break; 309 } 310 } 311 } 312 313 // There is already a declaration with the same name in the same 314 // scope, which is not a tag declaration. It must be found 315 // before we find the new declaration, so insert the new 316 // declaration at the end of the chain. 317 IdResolver.AddShadowedDecl(TD, PrevDecl); 318 319 return; 320 } 321 } 322 } else if (isa<FunctionDecl>(D) && 323 AllowOverloadingOfFunction(D, Context)) { 324 // We are pushing the name of a function, which might be an 325 // overloaded name. 326 FunctionDecl *FD = cast<FunctionDecl>(D); 327 IdentifierResolver::iterator Redecl 328 = std::find_if(IdResolver.begin(FD->getDeclName()), 329 IdResolver.end(), 330 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 331 FD)); 332 if (Redecl != IdResolver.end() && 333 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 334 // There is already a declaration of a function on our 335 // IdResolver chain. Replace it with this declaration. 336 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 337 IdResolver.RemoveDecl(*Redecl); 338 } 339 } else if (isa<ObjCInterfaceDecl>(D)) { 340 // We're pushing an Objective-C interface into the current 341 // context. If there is already an alias declaration, remove it first. 342 for (IdentifierResolver::iterator 343 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 344 I != IEnd; ++I) { 345 if (isa<ObjCCompatibleAliasDecl>(*I)) { 346 S->RemoveDecl(DeclPtrTy::make(*I)); 347 IdResolver.RemoveDecl(*I); 348 break; 349 } 350 } 351 } 352 353 IdResolver.AddDecl(D); 354} 355 356void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 357 if (S->decl_empty()) return; 358 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 359 "Scope shouldn't contain decls!"); 360 361 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 362 I != E; ++I) { 363 Decl *TmpD = (*I).getAs<Decl>(); 364 assert(TmpD && "This decl didn't get pushed??"); 365 366 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 367 NamedDecl *D = cast<NamedDecl>(TmpD); 368 369 if (!D->getDeclName()) continue; 370 371 // Remove this name from our lexical scope. 372 IdResolver.RemoveDecl(D); 373 } 374} 375 376/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 377/// return 0 if one not found. 378ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 379 // The third "scope" argument is 0 since we aren't enabling lazy built-in 380 // creation from this context. 381 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 382 383 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 384} 385 386/// getNonFieldDeclScope - Retrieves the innermost scope, starting 387/// from S, where a non-field would be declared. This routine copes 388/// with the difference between C and C++ scoping rules in structs and 389/// unions. For example, the following code is well-formed in C but 390/// ill-formed in C++: 391/// @code 392/// struct S6 { 393/// enum { BAR } e; 394/// }; 395/// 396/// void test_S6() { 397/// struct S6 a; 398/// a.e = BAR; 399/// } 400/// @endcode 401/// For the declaration of BAR, this routine will return a different 402/// scope. The scope S will be the scope of the unnamed enumeration 403/// within S6. In C++, this routine will return the scope associated 404/// with S6, because the enumeration's scope is a transparent 405/// context but structures can contain non-field names. In C, this 406/// routine will return the translation unit scope, since the 407/// enumeration's scope is a transparent context and structures cannot 408/// contain non-field names. 409Scope *Sema::getNonFieldDeclScope(Scope *S) { 410 while (((S->getFlags() & Scope::DeclScope) == 0) || 411 (S->getEntity() && 412 ((DeclContext *)S->getEntity())->isTransparentContext()) || 413 (S->isClassScope() && !getLangOptions().CPlusPlus)) 414 S = S->getParent(); 415 return S; 416} 417 418void Sema::InitBuiltinVaListType() { 419 if (!Context.getBuiltinVaListType().isNull()) 420 return; 421 422 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 423 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 424 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 425 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 426} 427 428/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 429/// file scope. lazily create a decl for it. ForRedeclaration is true 430/// if we're creating this built-in in anticipation of redeclaring the 431/// built-in. 432NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 433 Scope *S, bool ForRedeclaration, 434 SourceLocation Loc) { 435 Builtin::ID BID = (Builtin::ID)bid; 436 437 if (Context.BuiltinInfo.hasVAListUse(BID)) 438 InitBuiltinVaListType(); 439 440 ASTContext::GetBuiltinTypeError Error; 441 QualType R = Context.GetBuiltinType(BID, Error); 442 switch (Error) { 443 case ASTContext::GE_None: 444 // Okay 445 break; 446 447 case ASTContext::GE_Missing_FILE: 448 if (ForRedeclaration) 449 Diag(Loc, diag::err_implicit_decl_requires_stdio) 450 << Context.BuiltinInfo.GetName(BID); 451 return 0; 452 } 453 454 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 455 Diag(Loc, diag::ext_implicit_lib_function_decl) 456 << Context.BuiltinInfo.GetName(BID) 457 << R; 458 if (Context.BuiltinInfo.getHeaderName(BID) && 459 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 460 != Diagnostic::Ignored) 461 Diag(Loc, diag::note_please_include_header) 462 << Context.BuiltinInfo.getHeaderName(BID) 463 << Context.BuiltinInfo.GetName(BID); 464 } 465 466 FunctionDecl *New = FunctionDecl::Create(Context, 467 Context.getTranslationUnitDecl(), 468 Loc, II, R, 469 FunctionDecl::Extern, false, 470 /*hasPrototype=*/true); 471 New->setImplicit(); 472 473 // Create Decl objects for each parameter, adding them to the 474 // FunctionDecl. 475 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 476 llvm::SmallVector<ParmVarDecl*, 16> Params; 477 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 478 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 479 FT->getArgType(i), VarDecl::None, 0)); 480 New->setParams(Context, Params.data(), Params.size()); 481 } 482 483 AddKnownFunctionAttributes(New); 484 485 // TUScope is the translation-unit scope to insert this function into. 486 // FIXME: This is hideous. We need to teach PushOnScopeChains to 487 // relate Scopes to DeclContexts, and probably eliminate CurContext 488 // entirely, but we're not there yet. 489 DeclContext *SavedContext = CurContext; 490 CurContext = Context.getTranslationUnitDecl(); 491 PushOnScopeChains(New, TUScope); 492 CurContext = SavedContext; 493 return New; 494} 495 496/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 497/// everything from the standard library is defined. 498NamespaceDecl *Sema::GetStdNamespace() { 499 if (!StdNamespace) { 500 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 501 DeclContext *Global = Context.getTranslationUnitDecl(); 502 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 503 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 504 } 505 return StdNamespace; 506} 507 508/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 509/// same name and scope as a previous declaration 'Old'. Figure out 510/// how to resolve this situation, merging decls or emitting 511/// diagnostics as appropriate. If there was an error, set New to be invalid. 512/// 513void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 514 // If either decl is known invalid already, set the new one to be invalid and 515 // don't bother doing any merging checks. 516 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 517 return New->setInvalidDecl(); 518 519 bool objc_types = false; 520 521 // Allow multiple definitions for ObjC built-in typedefs. 522 // FIXME: Verify the underlying types are equivalent! 523 if (getLangOptions().ObjC1) { 524 const IdentifierInfo *TypeID = New->getIdentifier(); 525 switch (TypeID->getLength()) { 526 default: break; 527 case 2: 528 if (!TypeID->isStr("id")) 529 break; 530 Context.setObjCIdType(Context.getTypeDeclType(New)); 531 objc_types = true; 532 break; 533 case 5: 534 if (!TypeID->isStr("Class")) 535 break; 536 Context.setObjCClassType(Context.getTypeDeclType(New)); 537 return; 538 case 3: 539 if (!TypeID->isStr("SEL")) 540 break; 541 Context.setObjCSelType(Context.getTypeDeclType(New)); 542 return; 543 case 8: 544 if (!TypeID->isStr("Protocol")) 545 break; 546 Context.setObjCProtoType(New->getUnderlyingType()); 547 return; 548 } 549 // Fall through - the typedef name was not a builtin type. 550 } 551 // Verify the old decl was also a type. 552 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 553 if (!Old) { 554 Diag(New->getLocation(), diag::err_redefinition_different_kind) 555 << New->getDeclName(); 556 if (OldD->getLocation().isValid()) 557 Diag(OldD->getLocation(), diag::note_previous_definition); 558 return New->setInvalidDecl(); 559 } 560 561 // Determine the "old" type we'll use for checking and diagnostics. 562 QualType OldType; 563 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 564 OldType = OldTypedef->getUnderlyingType(); 565 else 566 OldType = Context.getTypeDeclType(Old); 567 568 // If the typedef types are not identical, reject them in all languages and 569 // with any extensions enabled. 570 571 if (OldType != New->getUnderlyingType() && 572 Context.getCanonicalType(OldType) != 573 Context.getCanonicalType(New->getUnderlyingType())) { 574 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 575 << New->getUnderlyingType() << OldType; 576 if (Old->getLocation().isValid()) 577 Diag(Old->getLocation(), diag::note_previous_definition); 578 return New->setInvalidDecl(); 579 } 580 581 if (objc_types || getLangOptions().Microsoft) 582 return; 583 584 // C++ [dcl.typedef]p2: 585 // In a given non-class scope, a typedef specifier can be used to 586 // redefine the name of any type declared in that scope to refer 587 // to the type to which it already refers. 588 if (getLangOptions().CPlusPlus) { 589 if (!isa<CXXRecordDecl>(CurContext)) 590 return; 591 Diag(New->getLocation(), diag::err_redefinition) 592 << New->getDeclName(); 593 Diag(Old->getLocation(), diag::note_previous_definition); 594 return New->setInvalidDecl(); 595 } 596 597 // If we have a redefinition of a typedef in C, emit a warning. This warning 598 // is normally mapped to an error, but can be controlled with 599 // -Wtypedef-redefinition. If either the original or the redefinition is 600 // in a system header, don't emit this for compatibility with GCC. 601 if (PP.getDiagnostics().getSuppressSystemWarnings() && 602 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 603 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 604 return; 605 606 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 607 << New->getDeclName(); 608 Diag(Old->getLocation(), diag::note_previous_definition); 609 return; 610} 611 612/// DeclhasAttr - returns true if decl Declaration already has the target 613/// attribute. 614static bool 615DeclHasAttr(ASTContext &Context, const Decl *decl, const Attr *target) { 616 for (const Attr *attr = decl->getAttrs(Context); attr; attr = attr->getNext()) 617 if (attr->getKind() == target->getKind()) 618 return true; 619 620 return false; 621} 622 623/// MergeAttributes - append attributes from the Old decl to the New one. 624static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 625 for (const Attr *attr = Old->getAttrs(C); attr; attr = attr->getNext()) { 626 if (!DeclHasAttr(C, New, attr) && attr->isMerged()) { 627 Attr *NewAttr = attr->clone(C); 628 NewAttr->setInherited(true); 629 New->addAttr(C, NewAttr); 630 } 631 } 632} 633 634/// Used in MergeFunctionDecl to keep track of function parameters in 635/// C. 636struct GNUCompatibleParamWarning { 637 ParmVarDecl *OldParm; 638 ParmVarDecl *NewParm; 639 QualType PromotedType; 640}; 641 642/// MergeFunctionDecl - We just parsed a function 'New' from 643/// declarator D which has the same name and scope as a previous 644/// declaration 'Old'. Figure out how to resolve this situation, 645/// merging decls or emitting diagnostics as appropriate. 646/// 647/// In C++, New and Old must be declarations that are not 648/// overloaded. Use IsOverload to determine whether New and Old are 649/// overloaded, and to select the Old declaration that New should be 650/// merged with. 651/// 652/// Returns true if there was an error, false otherwise. 653bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 654 assert(!isa<OverloadedFunctionDecl>(OldD) && 655 "Cannot merge with an overloaded function declaration"); 656 657 // Verify the old decl was also a function. 658 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 659 if (!Old) { 660 Diag(New->getLocation(), diag::err_redefinition_different_kind) 661 << New->getDeclName(); 662 Diag(OldD->getLocation(), diag::note_previous_definition); 663 return true; 664 } 665 666 // Determine whether the previous declaration was a definition, 667 // implicit declaration, or a declaration. 668 diag::kind PrevDiag; 669 if (Old->isThisDeclarationADefinition()) 670 PrevDiag = diag::note_previous_definition; 671 else if (Old->isImplicit()) 672 PrevDiag = diag::note_previous_implicit_declaration; 673 else 674 PrevDiag = diag::note_previous_declaration; 675 676 QualType OldQType = Context.getCanonicalType(Old->getType()); 677 QualType NewQType = Context.getCanonicalType(New->getType()); 678 679 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 680 New->getStorageClass() == FunctionDecl::Static && 681 Old->getStorageClass() != FunctionDecl::Static) { 682 Diag(New->getLocation(), diag::err_static_non_static) 683 << New; 684 Diag(Old->getLocation(), PrevDiag); 685 return true; 686 } 687 688 if (getLangOptions().CPlusPlus) { 689 // (C++98 13.1p2): 690 // Certain function declarations cannot be overloaded: 691 // -- Function declarations that differ only in the return type 692 // cannot be overloaded. 693 QualType OldReturnType 694 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 695 QualType NewReturnType 696 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 697 if (OldReturnType != NewReturnType) { 698 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 699 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 700 return true; 701 } 702 703 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 704 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 705 if (OldMethod && NewMethod && 706 OldMethod->getLexicalDeclContext() == 707 NewMethod->getLexicalDeclContext()) { 708 // -- Member function declarations with the same name and the 709 // same parameter types cannot be overloaded if any of them 710 // is a static member function declaration. 711 if (OldMethod->isStatic() || NewMethod->isStatic()) { 712 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 713 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 714 return true; 715 } 716 717 // C++ [class.mem]p1: 718 // [...] A member shall not be declared twice in the 719 // member-specification, except that a nested class or member 720 // class template can be declared and then later defined. 721 unsigned NewDiag; 722 if (isa<CXXConstructorDecl>(OldMethod)) 723 NewDiag = diag::err_constructor_redeclared; 724 else if (isa<CXXDestructorDecl>(NewMethod)) 725 NewDiag = diag::err_destructor_redeclared; 726 else if (isa<CXXConversionDecl>(NewMethod)) 727 NewDiag = diag::err_conv_function_redeclared; 728 else 729 NewDiag = diag::err_member_redeclared; 730 731 Diag(New->getLocation(), NewDiag); 732 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 733 } 734 735 // (C++98 8.3.5p3): 736 // All declarations for a function shall agree exactly in both the 737 // return type and the parameter-type-list. 738 if (OldQType == NewQType) 739 return MergeCompatibleFunctionDecls(New, Old); 740 741 // Fall through for conflicting redeclarations and redefinitions. 742 } 743 744 // C: Function types need to be compatible, not identical. This handles 745 // duplicate function decls like "void f(int); void f(enum X);" properly. 746 if (!getLangOptions().CPlusPlus && 747 Context.typesAreCompatible(OldQType, NewQType)) { 748 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 749 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 750 const FunctionProtoType *OldProto = 0; 751 if (isa<FunctionNoProtoType>(NewFuncType) && 752 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 753 // The old declaration provided a function prototype, but the 754 // new declaration does not. Merge in the prototype. 755 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 756 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 757 OldProto->arg_type_end()); 758 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 759 ParamTypes.data(), ParamTypes.size(), 760 OldProto->isVariadic(), 761 OldProto->getTypeQuals()); 762 New->setType(NewQType); 763 New->setHasInheritedPrototype(); 764 765 // Synthesize a parameter for each argument type. 766 llvm::SmallVector<ParmVarDecl*, 16> Params; 767 for (FunctionProtoType::arg_type_iterator 768 ParamType = OldProto->arg_type_begin(), 769 ParamEnd = OldProto->arg_type_end(); 770 ParamType != ParamEnd; ++ParamType) { 771 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 772 SourceLocation(), 0, 773 *ParamType, VarDecl::None, 774 0); 775 Param->setImplicit(); 776 Params.push_back(Param); 777 } 778 779 New->setParams(Context, Params.data(), Params.size()); 780 } 781 782 return MergeCompatibleFunctionDecls(New, Old); 783 } 784 785 // GNU C permits a K&R definition to follow a prototype declaration 786 // if the declared types of the parameters in the K&R definition 787 // match the types in the prototype declaration, even when the 788 // promoted types of the parameters from the K&R definition differ 789 // from the types in the prototype. GCC then keeps the types from 790 // the prototype. 791 // 792 // If a variadic prototype is followed by a non-variadic K&R definition, 793 // the K&R definition becomes variadic. This is sort of an edge case, but 794 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 795 // C99 6.9.1p8. 796 if (!getLangOptions().CPlusPlus && 797 Old->hasPrototype() && !New->hasPrototype() && 798 New->getType()->getAsFunctionProtoType() && 799 Old->getNumParams() == New->getNumParams()) { 800 llvm::SmallVector<QualType, 16> ArgTypes; 801 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 802 const FunctionProtoType *OldProto 803 = Old->getType()->getAsFunctionProtoType(); 804 const FunctionProtoType *NewProto 805 = New->getType()->getAsFunctionProtoType(); 806 807 // Determine whether this is the GNU C extension. 808 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 809 NewProto->getResultType()); 810 bool LooseCompatible = !MergedReturn.isNull(); 811 for (unsigned Idx = 0, End = Old->getNumParams(); 812 LooseCompatible && Idx != End; ++Idx) { 813 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 814 ParmVarDecl *NewParm = New->getParamDecl(Idx); 815 if (Context.typesAreCompatible(OldParm->getType(), 816 NewProto->getArgType(Idx))) { 817 ArgTypes.push_back(NewParm->getType()); 818 } else if (Context.typesAreCompatible(OldParm->getType(), 819 NewParm->getType())) { 820 GNUCompatibleParamWarning Warn 821 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 822 Warnings.push_back(Warn); 823 ArgTypes.push_back(NewParm->getType()); 824 } else 825 LooseCompatible = false; 826 } 827 828 if (LooseCompatible) { 829 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 830 Diag(Warnings[Warn].NewParm->getLocation(), 831 diag::ext_param_promoted_not_compatible_with_prototype) 832 << Warnings[Warn].PromotedType 833 << Warnings[Warn].OldParm->getType(); 834 Diag(Warnings[Warn].OldParm->getLocation(), 835 diag::note_previous_declaration); 836 } 837 838 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 839 ArgTypes.size(), 840 OldProto->isVariadic(), 0)); 841 return MergeCompatibleFunctionDecls(New, Old); 842 } 843 844 // Fall through to diagnose conflicting types. 845 } 846 847 // A function that has already been declared has been redeclared or defined 848 // with a different type- show appropriate diagnostic 849 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 850 // The user has declared a builtin function with an incompatible 851 // signature. 852 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 853 // The function the user is redeclaring is a library-defined 854 // function like 'malloc' or 'printf'. Warn about the 855 // redeclaration, then pretend that we don't know about this 856 // library built-in. 857 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 858 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 859 << Old << Old->getType(); 860 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 861 Old->setInvalidDecl(); 862 return false; 863 } 864 865 PrevDiag = diag::note_previous_builtin_declaration; 866 } 867 868 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 869 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 870 return true; 871} 872 873/// \brief Completes the merge of two function declarations that are 874/// known to be compatible. 875/// 876/// This routine handles the merging of attributes and other 877/// properties of function declarations form the old declaration to 878/// the new declaration, once we know that New is in fact a 879/// redeclaration of Old. 880/// 881/// \returns false 882bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 883 // Merge the attributes 884 MergeAttributes(New, Old, Context); 885 886 // Merge the storage class. 887 if (Old->getStorageClass() != FunctionDecl::Extern) 888 New->setStorageClass(Old->getStorageClass()); 889 890 // Merge "inline" 891 if (Old->isInline()) 892 New->setInline(true); 893 894 // If this function declaration by itself qualifies as a C99 inline 895 // definition (C99 6.7.4p6), but the previous definition did not, 896 // then the function is not a C99 inline definition. 897 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 898 New->setC99InlineDefinition(false); 899 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 900 // Mark all preceding definitions as not being C99 inline definitions. 901 for (const FunctionDecl *Prev = Old; Prev; 902 Prev = Prev->getPreviousDeclaration()) 903 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 904 } 905 906 // Merge "pure" flag. 907 if (Old->isPure()) 908 New->setPure(); 909 910 // Merge the "deleted" flag. 911 if (Old->isDeleted()) 912 New->setDeleted(); 913 914 if (getLangOptions().CPlusPlus) 915 return MergeCXXFunctionDecl(New, Old); 916 917 return false; 918} 919 920/// MergeVarDecl - We just parsed a variable 'New' which has the same name 921/// and scope as a previous declaration 'Old'. Figure out how to resolve this 922/// situation, merging decls or emitting diagnostics as appropriate. 923/// 924/// Tentative definition rules (C99 6.9.2p2) are checked by 925/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 926/// definitions here, since the initializer hasn't been attached. 927/// 928void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 929 // If either decl is invalid, make sure the new one is marked invalid and 930 // don't do any other checking. 931 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 932 return New->setInvalidDecl(); 933 934 // Verify the old decl was also a variable. 935 VarDecl *Old = dyn_cast<VarDecl>(OldD); 936 if (!Old) { 937 Diag(New->getLocation(), diag::err_redefinition_different_kind) 938 << New->getDeclName(); 939 Diag(OldD->getLocation(), diag::note_previous_definition); 940 return New->setInvalidDecl(); 941 } 942 943 MergeAttributes(New, Old, Context); 944 945 // Merge the types 946 QualType MergedT; 947 if (getLangOptions().CPlusPlus) { 948 if (Context.hasSameType(New->getType(), Old->getType())) 949 MergedT = New->getType(); 950 } else { 951 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 952 } 953 if (MergedT.isNull()) { 954 Diag(New->getLocation(), diag::err_redefinition_different_type) 955 << New->getDeclName(); 956 Diag(Old->getLocation(), diag::note_previous_definition); 957 return New->setInvalidDecl(); 958 } 959 New->setType(MergedT); 960 961 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 962 if (New->getStorageClass() == VarDecl::Static && 963 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 964 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 965 Diag(Old->getLocation(), diag::note_previous_definition); 966 return New->setInvalidDecl(); 967 } 968 // C99 6.2.2p4: 969 // For an identifier declared with the storage-class specifier 970 // extern in a scope in which a prior declaration of that 971 // identifier is visible,23) if the prior declaration specifies 972 // internal or external linkage, the linkage of the identifier at 973 // the later declaration is the same as the linkage specified at 974 // the prior declaration. If no prior declaration is visible, or 975 // if the prior declaration specifies no linkage, then the 976 // identifier has external linkage. 977 if (New->hasExternalStorage() && Old->hasLinkage()) 978 /* Okay */; 979 else if (New->getStorageClass() != VarDecl::Static && 980 Old->getStorageClass() == VarDecl::Static) { 981 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 982 Diag(Old->getLocation(), diag::note_previous_definition); 983 return New->setInvalidDecl(); 984 } 985 986 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 987 988 // FIXME: The test for external storage here seems wrong? We still 989 // need to check for mismatches. 990 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 991 // Don't complain about out-of-line definitions of static members. 992 !(Old->getLexicalDeclContext()->isRecord() && 993 !New->getLexicalDeclContext()->isRecord())) { 994 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 995 Diag(Old->getLocation(), diag::note_previous_definition); 996 return New->setInvalidDecl(); 997 } 998 999 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1000 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1001 Diag(Old->getLocation(), diag::note_previous_definition); 1002 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1003 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1004 Diag(Old->getLocation(), diag::note_previous_definition); 1005 } 1006 1007 // Keep a chain of previous declarations. 1008 New->setPreviousDeclaration(Old); 1009} 1010 1011/// CheckParmsForFunctionDef - Check that the parameters of the given 1012/// function are appropriate for the definition of a function. This 1013/// takes care of any checks that cannot be performed on the 1014/// declaration itself, e.g., that the types of each of the function 1015/// parameters are complete. 1016bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1017 bool HasInvalidParm = false; 1018 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1019 ParmVarDecl *Param = FD->getParamDecl(p); 1020 1021 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1022 // function declarator that is part of a function definition of 1023 // that function shall not have incomplete type. 1024 // 1025 // This is also C++ [dcl.fct]p6. 1026 if (!Param->isInvalidDecl() && 1027 RequireCompleteType(Param->getLocation(), Param->getType(), 1028 diag::err_typecheck_decl_incomplete_type)) { 1029 Param->setInvalidDecl(); 1030 HasInvalidParm = true; 1031 } 1032 1033 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1034 // declaration of each parameter shall include an identifier. 1035 if (Param->getIdentifier() == 0 && 1036 !Param->isImplicit() && 1037 !getLangOptions().CPlusPlus) 1038 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1039 } 1040 1041 return HasInvalidParm; 1042} 1043 1044/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1045/// no declarator (e.g. "struct foo;") is parsed. 1046Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1047 // FIXME: Error on auto/register at file scope 1048 // FIXME: Error on inline/virtual/explicit 1049 // FIXME: Error on invalid restrict 1050 // FIXME: Warn on useless __thread 1051 // FIXME: Warn on useless const/volatile 1052 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1053 // FIXME: Warn on useless attributes 1054 TagDecl *Tag = 0; 1055 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1056 DS.getTypeSpecType() == DeclSpec::TST_struct || 1057 DS.getTypeSpecType() == DeclSpec::TST_union || 1058 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1059 if (!DS.getTypeRep()) // We probably had an error 1060 return DeclPtrTy(); 1061 1062 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1063 } 1064 1065 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1066 if (!Record->getDeclName() && Record->isDefinition() && 1067 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1068 if (getLangOptions().CPlusPlus || 1069 Record->getDeclContext()->isRecord()) 1070 return BuildAnonymousStructOrUnion(S, DS, Record); 1071 1072 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1073 << DS.getSourceRange(); 1074 } 1075 1076 // Microsoft allows unnamed struct/union fields. Don't complain 1077 // about them. 1078 // FIXME: Should we support Microsoft's extensions in this area? 1079 if (Record->getDeclName() && getLangOptions().Microsoft) 1080 return DeclPtrTy::make(Tag); 1081 } 1082 1083 if (!DS.isMissingDeclaratorOk() && 1084 DS.getTypeSpecType() != DeclSpec::TST_error) { 1085 // Warn about typedefs of enums without names, since this is an 1086 // extension in both Microsoft an GNU. 1087 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1088 Tag && isa<EnumDecl>(Tag)) { 1089 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1090 << DS.getSourceRange(); 1091 return DeclPtrTy::make(Tag); 1092 } 1093 1094 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1095 << DS.getSourceRange(); 1096 return DeclPtrTy(); 1097 } 1098 1099 return DeclPtrTy::make(Tag); 1100} 1101 1102/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1103/// anonymous struct or union AnonRecord into the owning context Owner 1104/// and scope S. This routine will be invoked just after we realize 1105/// that an unnamed union or struct is actually an anonymous union or 1106/// struct, e.g., 1107/// 1108/// @code 1109/// union { 1110/// int i; 1111/// float f; 1112/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1113/// // f into the surrounding scope.x 1114/// @endcode 1115/// 1116/// This routine is recursive, injecting the names of nested anonymous 1117/// structs/unions into the owning context and scope as well. 1118bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1119 RecordDecl *AnonRecord) { 1120 bool Invalid = false; 1121 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1122 FEnd = AnonRecord->field_end(Context); 1123 F != FEnd; ++F) { 1124 if ((*F)->getDeclName()) { 1125 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1126 LookupOrdinaryName, true); 1127 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1128 // C++ [class.union]p2: 1129 // The names of the members of an anonymous union shall be 1130 // distinct from the names of any other entity in the 1131 // scope in which the anonymous union is declared. 1132 unsigned diagKind 1133 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1134 : diag::err_anonymous_struct_member_redecl; 1135 Diag((*F)->getLocation(), diagKind) 1136 << (*F)->getDeclName(); 1137 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1138 Invalid = true; 1139 } else { 1140 // C++ [class.union]p2: 1141 // For the purpose of name lookup, after the anonymous union 1142 // definition, the members of the anonymous union are 1143 // considered to have been defined in the scope in which the 1144 // anonymous union is declared. 1145 Owner->makeDeclVisibleInContext(Context, *F); 1146 S->AddDecl(DeclPtrTy::make(*F)); 1147 IdResolver.AddDecl(*F); 1148 } 1149 } else if (const RecordType *InnerRecordType 1150 = (*F)->getType()->getAsRecordType()) { 1151 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1152 if (InnerRecord->isAnonymousStructOrUnion()) 1153 Invalid = Invalid || 1154 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1155 } 1156 } 1157 1158 return Invalid; 1159} 1160 1161/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1162/// anonymous structure or union. Anonymous unions are a C++ feature 1163/// (C++ [class.union]) and a GNU C extension; anonymous structures 1164/// are a GNU C and GNU C++ extension. 1165Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1166 RecordDecl *Record) { 1167 DeclContext *Owner = Record->getDeclContext(); 1168 1169 // Diagnose whether this anonymous struct/union is an extension. 1170 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1171 Diag(Record->getLocation(), diag::ext_anonymous_union); 1172 else if (!Record->isUnion()) 1173 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1174 1175 // C and C++ require different kinds of checks for anonymous 1176 // structs/unions. 1177 bool Invalid = false; 1178 if (getLangOptions().CPlusPlus) { 1179 const char* PrevSpec = 0; 1180 // C++ [class.union]p3: 1181 // Anonymous unions declared in a named namespace or in the 1182 // global namespace shall be declared static. 1183 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1184 (isa<TranslationUnitDecl>(Owner) || 1185 (isa<NamespaceDecl>(Owner) && 1186 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1187 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1188 Invalid = true; 1189 1190 // Recover by adding 'static'. 1191 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1192 } 1193 // C++ [class.union]p3: 1194 // A storage class is not allowed in a declaration of an 1195 // anonymous union in a class scope. 1196 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1197 isa<RecordDecl>(Owner)) { 1198 Diag(DS.getStorageClassSpecLoc(), 1199 diag::err_anonymous_union_with_storage_spec); 1200 Invalid = true; 1201 1202 // Recover by removing the storage specifier. 1203 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1204 PrevSpec); 1205 } 1206 1207 // C++ [class.union]p2: 1208 // The member-specification of an anonymous union shall only 1209 // define non-static data members. [Note: nested types and 1210 // functions cannot be declared within an anonymous union. ] 1211 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1212 MemEnd = Record->decls_end(Context); 1213 Mem != MemEnd; ++Mem) { 1214 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1215 // C++ [class.union]p3: 1216 // An anonymous union shall not have private or protected 1217 // members (clause 11). 1218 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1219 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1220 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1221 Invalid = true; 1222 } 1223 } else if ((*Mem)->isImplicit()) { 1224 // Any implicit members are fine. 1225 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1226 // This is a type that showed up in an 1227 // elaborated-type-specifier inside the anonymous struct or 1228 // union, but which actually declares a type outside of the 1229 // anonymous struct or union. It's okay. 1230 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1231 if (!MemRecord->isAnonymousStructOrUnion() && 1232 MemRecord->getDeclName()) { 1233 // This is a nested type declaration. 1234 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1235 << (int)Record->isUnion(); 1236 Invalid = true; 1237 } 1238 } else { 1239 // We have something that isn't a non-static data 1240 // member. Complain about it. 1241 unsigned DK = diag::err_anonymous_record_bad_member; 1242 if (isa<TypeDecl>(*Mem)) 1243 DK = diag::err_anonymous_record_with_type; 1244 else if (isa<FunctionDecl>(*Mem)) 1245 DK = diag::err_anonymous_record_with_function; 1246 else if (isa<VarDecl>(*Mem)) 1247 DK = diag::err_anonymous_record_with_static; 1248 Diag((*Mem)->getLocation(), DK) 1249 << (int)Record->isUnion(); 1250 Invalid = true; 1251 } 1252 } 1253 } 1254 1255 if (!Record->isUnion() && !Owner->isRecord()) { 1256 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1257 << (int)getLangOptions().CPlusPlus; 1258 Invalid = true; 1259 } 1260 1261 // Create a declaration for this anonymous struct/union. 1262 NamedDecl *Anon = 0; 1263 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1264 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1265 /*IdentifierInfo=*/0, 1266 Context.getTypeDeclType(Record), 1267 /*BitWidth=*/0, /*Mutable=*/false); 1268 Anon->setAccess(AS_public); 1269 if (getLangOptions().CPlusPlus) 1270 FieldCollector->Add(cast<FieldDecl>(Anon)); 1271 } else { 1272 VarDecl::StorageClass SC; 1273 switch (DS.getStorageClassSpec()) { 1274 default: assert(0 && "Unknown storage class!"); 1275 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1276 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1277 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1278 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1279 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1280 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1281 case DeclSpec::SCS_mutable: 1282 // mutable can only appear on non-static class members, so it's always 1283 // an error here 1284 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1285 Invalid = true; 1286 SC = VarDecl::None; 1287 break; 1288 } 1289 1290 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1291 /*IdentifierInfo=*/0, 1292 Context.getTypeDeclType(Record), 1293 SC, DS.getSourceRange().getBegin()); 1294 } 1295 Anon->setImplicit(); 1296 1297 // Add the anonymous struct/union object to the current 1298 // context. We'll be referencing this object when we refer to one of 1299 // its members. 1300 Owner->addDecl(Context, Anon); 1301 1302 // Inject the members of the anonymous struct/union into the owning 1303 // context and into the identifier resolver chain for name lookup 1304 // purposes. 1305 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1306 Invalid = true; 1307 1308 // Mark this as an anonymous struct/union type. Note that we do not 1309 // do this until after we have already checked and injected the 1310 // members of this anonymous struct/union type, because otherwise 1311 // the members could be injected twice: once by DeclContext when it 1312 // builds its lookup table, and once by 1313 // InjectAnonymousStructOrUnionMembers. 1314 Record->setAnonymousStructOrUnion(true); 1315 1316 if (Invalid) 1317 Anon->setInvalidDecl(); 1318 1319 return DeclPtrTy::make(Anon); 1320} 1321 1322 1323/// GetNameForDeclarator - Determine the full declaration name for the 1324/// given Declarator. 1325DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1326 switch (D.getKind()) { 1327 case Declarator::DK_Abstract: 1328 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1329 return DeclarationName(); 1330 1331 case Declarator::DK_Normal: 1332 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1333 return DeclarationName(D.getIdentifier()); 1334 1335 case Declarator::DK_Constructor: { 1336 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1337 Ty = Context.getCanonicalType(Ty); 1338 return Context.DeclarationNames.getCXXConstructorName(Ty); 1339 } 1340 1341 case Declarator::DK_Destructor: { 1342 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1343 Ty = Context.getCanonicalType(Ty); 1344 return Context.DeclarationNames.getCXXDestructorName(Ty); 1345 } 1346 1347 case Declarator::DK_Conversion: { 1348 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1349 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1350 Ty = Context.getCanonicalType(Ty); 1351 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1352 } 1353 1354 case Declarator::DK_Operator: 1355 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1356 return Context.DeclarationNames.getCXXOperatorName( 1357 D.getOverloadedOperator()); 1358 } 1359 1360 assert(false && "Unknown name kind"); 1361 return DeclarationName(); 1362} 1363 1364/// isNearlyMatchingFunction - Determine whether the C++ functions 1365/// Declaration and Definition are "nearly" matching. This heuristic 1366/// is used to improve diagnostics in the case where an out-of-line 1367/// function definition doesn't match any declaration within 1368/// the class or namespace. 1369static bool isNearlyMatchingFunction(ASTContext &Context, 1370 FunctionDecl *Declaration, 1371 FunctionDecl *Definition) { 1372 if (Declaration->param_size() != Definition->param_size()) 1373 return false; 1374 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1375 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1376 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1377 1378 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1379 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1380 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1381 return false; 1382 } 1383 1384 return true; 1385} 1386 1387Sema::DeclPtrTy 1388Sema::HandleDeclarator(Scope *S, Declarator &D, 1389 MultiTemplateParamsArg TemplateParamLists, 1390 bool IsFunctionDefinition) { 1391 DeclarationName Name = GetNameForDeclarator(D); 1392 1393 // All of these full declarators require an identifier. If it doesn't have 1394 // one, the ParsedFreeStandingDeclSpec action should be used. 1395 if (!Name) { 1396 if (!D.isInvalidType()) // Reject this if we think it is valid. 1397 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1398 diag::err_declarator_need_ident) 1399 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1400 return DeclPtrTy(); 1401 } 1402 1403 // The scope passed in may not be a decl scope. Zip up the scope tree until 1404 // we find one that is. 1405 while ((S->getFlags() & Scope::DeclScope) == 0 || 1406 (S->getFlags() & Scope::TemplateParamScope) != 0) 1407 S = S->getParent(); 1408 1409 DeclContext *DC; 1410 NamedDecl *PrevDecl; 1411 NamedDecl *New; 1412 1413 QualType R = GetTypeForDeclarator(D, S); 1414 1415 // See if this is a redefinition of a variable in the same scope. 1416 if (D.getCXXScopeSpec().isInvalid()) { 1417 DC = CurContext; 1418 PrevDecl = 0; 1419 D.setInvalidType(); 1420 } else if (!D.getCXXScopeSpec().isSet()) { 1421 LookupNameKind NameKind = LookupOrdinaryName; 1422 1423 // If the declaration we're planning to build will be a function 1424 // or object with linkage, then look for another declaration with 1425 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1426 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1427 /* Do nothing*/; 1428 else if (R->isFunctionType()) { 1429 if (CurContext->isFunctionOrMethod()) 1430 NameKind = LookupRedeclarationWithLinkage; 1431 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1432 NameKind = LookupRedeclarationWithLinkage; 1433 1434 DC = CurContext; 1435 PrevDecl = LookupName(S, Name, NameKind, true, 1436 D.getDeclSpec().getStorageClassSpec() != 1437 DeclSpec::SCS_static, 1438 D.getIdentifierLoc()); 1439 } else { // Something like "int foo::x;" 1440 DC = computeDeclContext(D.getCXXScopeSpec()); 1441 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1442 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1443 1444 // C++ 7.3.1.2p2: 1445 // Members (including explicit specializations of templates) of a named 1446 // namespace can also be defined outside that namespace by explicit 1447 // qualification of the name being defined, provided that the entity being 1448 // defined was already declared in the namespace and the definition appears 1449 // after the point of declaration in a namespace that encloses the 1450 // declarations namespace. 1451 // 1452 // Note that we only check the context at this point. We don't yet 1453 // have enough information to make sure that PrevDecl is actually 1454 // the declaration we want to match. For example, given: 1455 // 1456 // class X { 1457 // void f(); 1458 // void f(float); 1459 // }; 1460 // 1461 // void X::f(int) { } // ill-formed 1462 // 1463 // In this case, PrevDecl will point to the overload set 1464 // containing the two f's declared in X, but neither of them 1465 // matches. 1466 1467 // First check whether we named the global scope. 1468 if (isa<TranslationUnitDecl>(DC)) { 1469 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1470 << Name << D.getCXXScopeSpec().getRange(); 1471 } else if (!CurContext->Encloses(DC)) { 1472 // The qualifying scope doesn't enclose the original declaration. 1473 // Emit diagnostic based on current scope. 1474 SourceLocation L = D.getIdentifierLoc(); 1475 SourceRange R = D.getCXXScopeSpec().getRange(); 1476 if (isa<FunctionDecl>(CurContext)) 1477 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1478 else 1479 Diag(L, diag::err_invalid_declarator_scope) 1480 << Name << cast<NamedDecl>(DC) << R; 1481 D.setInvalidType(); 1482 } 1483 } 1484 1485 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1486 // Maybe we will complain about the shadowed template parameter. 1487 if (!D.isInvalidType()) 1488 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1489 D.setInvalidType(); 1490 1491 // Just pretend that we didn't see the previous declaration. 1492 PrevDecl = 0; 1493 } 1494 1495 // In C++, the previous declaration we find might be a tag type 1496 // (class or enum). In this case, the new declaration will hide the 1497 // tag type. Note that this does does not apply if we're declaring a 1498 // typedef (C++ [dcl.typedef]p4). 1499 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1500 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1501 PrevDecl = 0; 1502 1503 bool Redeclaration = false; 1504 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1505 if (TemplateParamLists.size()) { 1506 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1507 return DeclPtrTy(); 1508 } 1509 1510 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1511 } else if (R->isFunctionType()) { 1512 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1513 move(TemplateParamLists), 1514 IsFunctionDefinition, Redeclaration); 1515 } else { 1516 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1517 } 1518 1519 if (New == 0) 1520 return DeclPtrTy(); 1521 1522 // If this has an identifier and is not an invalid redeclaration, 1523 // add it to the scope stack. 1524 if (Name && !(Redeclaration && New->isInvalidDecl())) 1525 PushOnScopeChains(New, S); 1526 1527 return DeclPtrTy::make(New); 1528} 1529 1530/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1531/// types into constant array types in certain situations which would otherwise 1532/// be errors (for GCC compatibility). 1533static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1534 ASTContext &Context, 1535 bool &SizeIsNegative) { 1536 // This method tries to turn a variable array into a constant 1537 // array even when the size isn't an ICE. This is necessary 1538 // for compatibility with code that depends on gcc's buggy 1539 // constant expression folding, like struct {char x[(int)(char*)2];} 1540 SizeIsNegative = false; 1541 1542 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1543 QualType Pointee = PTy->getPointeeType(); 1544 QualType FixedType = 1545 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1546 if (FixedType.isNull()) return FixedType; 1547 FixedType = Context.getPointerType(FixedType); 1548 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1549 return FixedType; 1550 } 1551 1552 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1553 if (!VLATy) 1554 return QualType(); 1555 // FIXME: We should probably handle this case 1556 if (VLATy->getElementType()->isVariablyModifiedType()) 1557 return QualType(); 1558 1559 Expr::EvalResult EvalResult; 1560 if (!VLATy->getSizeExpr() || 1561 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1562 !EvalResult.Val.isInt()) 1563 return QualType(); 1564 1565 llvm::APSInt &Res = EvalResult.Val.getInt(); 1566 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1567 return Context.getConstantArrayType(VLATy->getElementType(), 1568 Res, ArrayType::Normal, 0); 1569 1570 SizeIsNegative = true; 1571 return QualType(); 1572} 1573 1574/// \brief Register the given locally-scoped external C declaration so 1575/// that it can be found later for redeclarations 1576void 1577Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1578 Scope *S) { 1579 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1580 "Decl is not a locally-scoped decl!"); 1581 // Note that we have a locally-scoped external with this name. 1582 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1583 1584 if (!PrevDecl) 1585 return; 1586 1587 // If there was a previous declaration of this variable, it may be 1588 // in our identifier chain. Update the identifier chain with the new 1589 // declaration. 1590 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1591 // The previous declaration was found on the identifer resolver 1592 // chain, so remove it from its scope. 1593 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1594 S = S->getParent(); 1595 1596 if (S) 1597 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1598 } 1599} 1600 1601/// \brief Diagnose function specifiers on a declaration of an identifier that 1602/// does not identify a function. 1603void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1604 // FIXME: We should probably indicate the identifier in question to avoid 1605 // confusion for constructs like "inline int a(), b;" 1606 if (D.getDeclSpec().isInlineSpecified()) 1607 Diag(D.getDeclSpec().getInlineSpecLoc(), 1608 diag::err_inline_non_function); 1609 1610 if (D.getDeclSpec().isVirtualSpecified()) 1611 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1612 diag::err_virtual_non_function); 1613 1614 if (D.getDeclSpec().isExplicitSpecified()) 1615 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1616 diag::err_explicit_non_function); 1617} 1618 1619NamedDecl* 1620Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1621 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1622 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1623 if (D.getCXXScopeSpec().isSet()) { 1624 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1625 << D.getCXXScopeSpec().getRange(); 1626 D.setInvalidType(); 1627 // Pretend we didn't see the scope specifier. 1628 DC = 0; 1629 } 1630 1631 if (getLangOptions().CPlusPlus) { 1632 // Check that there are no default arguments (C++ only). 1633 CheckExtraCXXDefaultArguments(D); 1634 } 1635 1636 DiagnoseFunctionSpecifiers(D); 1637 1638 if (D.getDeclSpec().isThreadSpecified()) 1639 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1640 1641 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1642 if (!NewTD) return 0; 1643 1644 if (D.isInvalidType()) 1645 NewTD->setInvalidDecl(); 1646 1647 // Handle attributes prior to checking for duplicates in MergeVarDecl 1648 ProcessDeclAttributes(S, NewTD, D); 1649 // Merge the decl with the existing one if appropriate. If the decl is 1650 // in an outer scope, it isn't the same thing. 1651 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1652 Redeclaration = true; 1653 MergeTypeDefDecl(NewTD, PrevDecl); 1654 } 1655 1656 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1657 // then it shall have block scope. 1658 QualType T = NewTD->getUnderlyingType(); 1659 if (T->isVariablyModifiedType()) { 1660 CurFunctionNeedsScopeChecking = true; 1661 1662 if (S->getFnParent() == 0) { 1663 bool SizeIsNegative; 1664 QualType FixedTy = 1665 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1666 if (!FixedTy.isNull()) { 1667 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1668 NewTD->setUnderlyingType(FixedTy); 1669 } else { 1670 if (SizeIsNegative) 1671 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1672 else if (T->isVariableArrayType()) 1673 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1674 else 1675 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1676 NewTD->setInvalidDecl(); 1677 } 1678 } 1679 } 1680 return NewTD; 1681} 1682 1683/// \brief Determines whether the given declaration is an out-of-scope 1684/// previous declaration. 1685/// 1686/// This routine should be invoked when name lookup has found a 1687/// previous declaration (PrevDecl) that is not in the scope where a 1688/// new declaration by the same name is being introduced. If the new 1689/// declaration occurs in a local scope, previous declarations with 1690/// linkage may still be considered previous declarations (C99 1691/// 6.2.2p4-5, C++ [basic.link]p6). 1692/// 1693/// \param PrevDecl the previous declaration found by name 1694/// lookup 1695/// 1696/// \param DC the context in which the new declaration is being 1697/// declared. 1698/// 1699/// \returns true if PrevDecl is an out-of-scope previous declaration 1700/// for a new delcaration with the same name. 1701static bool 1702isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1703 ASTContext &Context) { 1704 if (!PrevDecl) 1705 return 0; 1706 1707 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1708 // case we need to check each of the overloaded functions. 1709 if (!PrevDecl->hasLinkage()) 1710 return false; 1711 1712 if (Context.getLangOptions().CPlusPlus) { 1713 // C++ [basic.link]p6: 1714 // If there is a visible declaration of an entity with linkage 1715 // having the same name and type, ignoring entities declared 1716 // outside the innermost enclosing namespace scope, the block 1717 // scope declaration declares that same entity and receives the 1718 // linkage of the previous declaration. 1719 DeclContext *OuterContext = DC->getLookupContext(); 1720 if (!OuterContext->isFunctionOrMethod()) 1721 // This rule only applies to block-scope declarations. 1722 return false; 1723 else { 1724 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1725 if (PrevOuterContext->isRecord()) 1726 // We found a member function: ignore it. 1727 return false; 1728 else { 1729 // Find the innermost enclosing namespace for the new and 1730 // previous declarations. 1731 while (!OuterContext->isFileContext()) 1732 OuterContext = OuterContext->getParent(); 1733 while (!PrevOuterContext->isFileContext()) 1734 PrevOuterContext = PrevOuterContext->getParent(); 1735 1736 // The previous declaration is in a different namespace, so it 1737 // isn't the same function. 1738 if (OuterContext->getPrimaryContext() != 1739 PrevOuterContext->getPrimaryContext()) 1740 return false; 1741 } 1742 } 1743 } 1744 1745 return true; 1746} 1747 1748NamedDecl* 1749Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1750 QualType R,NamedDecl* PrevDecl, 1751 bool &Redeclaration) { 1752 DeclarationName Name = GetNameForDeclarator(D); 1753 1754 // Check that there are no default arguments (C++ only). 1755 if (getLangOptions().CPlusPlus) 1756 CheckExtraCXXDefaultArguments(D); 1757 1758 VarDecl *NewVD; 1759 VarDecl::StorageClass SC; 1760 switch (D.getDeclSpec().getStorageClassSpec()) { 1761 default: assert(0 && "Unknown storage class!"); 1762 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1763 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1764 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1765 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1766 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1767 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1768 case DeclSpec::SCS_mutable: 1769 // mutable can only appear on non-static class members, so it's always 1770 // an error here 1771 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1772 D.setInvalidType(); 1773 SC = VarDecl::None; 1774 break; 1775 } 1776 1777 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1778 if (!II) { 1779 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1780 << Name.getAsString(); 1781 return 0; 1782 } 1783 1784 DiagnoseFunctionSpecifiers(D); 1785 1786 if (!DC->isRecord() && S->getFnParent() == 0) { 1787 // C99 6.9p2: The storage-class specifiers auto and register shall not 1788 // appear in the declaration specifiers in an external declaration. 1789 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1790 1791 // If this is a register variable with an asm label specified, then this 1792 // is a GNU extension. 1793 if (SC == VarDecl::Register && D.getAsmLabel()) 1794 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1795 else 1796 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1797 D.setInvalidType(); 1798 } 1799 } 1800 if (DC->isRecord() && !CurContext->isRecord()) { 1801 // This is an out-of-line definition of a static data member. 1802 if (SC == VarDecl::Static) { 1803 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1804 diag::err_static_out_of_line) 1805 << CodeModificationHint::CreateRemoval( 1806 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1807 } else if (SC == VarDecl::None) 1808 SC = VarDecl::Static; 1809 } 1810 if (SC == VarDecl::Static) { 1811 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 1812 if (RD->isLocalClass()) 1813 Diag(D.getIdentifierLoc(), 1814 diag::err_static_data_member_not_allowed_in_local_class) 1815 << Name << RD->getDeclName(); 1816 } 1817 } 1818 1819 1820 // The variable can not 1821 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1822 II, R, SC, 1823 // FIXME: Move to DeclGroup... 1824 D.getDeclSpec().getSourceRange().getBegin()); 1825 1826 if (D.isInvalidType()) 1827 NewVD->setInvalidDecl(); 1828 1829 if (D.getDeclSpec().isThreadSpecified()) { 1830 if (NewVD->hasLocalStorage()) 1831 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1832 else if (!Context.Target.isTLSSupported()) 1833 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1834 else 1835 NewVD->setThreadSpecified(true); 1836 } 1837 1838 // Set the lexical context. If the declarator has a C++ scope specifier, the 1839 // lexical context will be different from the semantic context. 1840 NewVD->setLexicalDeclContext(CurContext); 1841 1842 // Handle attributes prior to checking for duplicates in MergeVarDecl 1843 ProcessDeclAttributes(S, NewVD, D); 1844 1845 // Handle GNU asm-label extension (encoded as an attribute). 1846 if (Expr *E = (Expr*) D.getAsmLabel()) { 1847 // The parser guarantees this is a string. 1848 StringLiteral *SE = cast<StringLiteral>(E); 1849 NewVD->addAttr(Context, 1850 ::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1851 SE->getByteLength()))); 1852 } 1853 1854 // If name lookup finds a previous declaration that is not in the 1855 // same scope as the new declaration, this may still be an 1856 // acceptable redeclaration. 1857 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1858 !(NewVD->hasLinkage() && 1859 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1860 PrevDecl = 0; 1861 1862 // Merge the decl with the existing one if appropriate. 1863 if (PrevDecl) { 1864 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1865 // The user tried to define a non-static data member 1866 // out-of-line (C++ [dcl.meaning]p1). 1867 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1868 << D.getCXXScopeSpec().getRange(); 1869 PrevDecl = 0; 1870 NewVD->setInvalidDecl(); 1871 } 1872 } else if (D.getCXXScopeSpec().isSet()) { 1873 // No previous declaration in the qualifying scope. 1874 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1875 << Name << D.getCXXScopeSpec().getRange(); 1876 NewVD->setInvalidDecl(); 1877 } 1878 1879 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1880 1881 // If this is a locally-scoped extern C variable, update the map of 1882 // such variables. 1883 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1884 !NewVD->isInvalidDecl()) 1885 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1886 1887 return NewVD; 1888} 1889 1890/// \brief Perform semantic checking on a newly-created variable 1891/// declaration. 1892/// 1893/// This routine performs all of the type-checking required for a 1894/// variable declaration once it has been built. It is used both to 1895/// check variables after they have been parsed and their declarators 1896/// have been translated into a declaration, and to check variables 1897/// that have been instantiated from a template. 1898/// 1899/// Sets NewVD->isInvalidDecl() if an error was encountered. 1900void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1901 bool &Redeclaration) { 1902 // If the decl is already known invalid, don't check it. 1903 if (NewVD->isInvalidDecl()) 1904 return; 1905 1906 QualType T = NewVD->getType(); 1907 1908 if (T->isObjCInterfaceType()) { 1909 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1910 return NewVD->setInvalidDecl(); 1911 } 1912 1913 // The variable can not have an abstract class type. 1914 if (RequireNonAbstractType(NewVD->getLocation(), T, 1915 diag::err_abstract_type_in_decl, 1916 AbstractVariableType)) 1917 return NewVD->setInvalidDecl(); 1918 1919 // Emit an error if an address space was applied to decl with local storage. 1920 // This includes arrays of objects with address space qualifiers, but not 1921 // automatic variables that point to other address spaces. 1922 // ISO/IEC TR 18037 S5.1.2 1923 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1924 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1925 return NewVD->setInvalidDecl(); 1926 } 1927 1928 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1929 && !NewVD->hasAttr<BlocksAttr>(Context)) 1930 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1931 1932 bool isVM = T->isVariablyModifiedType(); 1933 if (isVM || NewVD->hasAttr<CleanupAttr>(Context)) 1934 CurFunctionNeedsScopeChecking = true; 1935 1936 if ((isVM && NewVD->hasLinkage()) || 1937 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1938 bool SizeIsNegative; 1939 QualType FixedTy = 1940 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1941 1942 if (FixedTy.isNull() && T->isVariableArrayType()) { 1943 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1944 // FIXME: This won't give the correct result for 1945 // int a[10][n]; 1946 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1947 1948 if (NewVD->isFileVarDecl()) 1949 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1950 << SizeRange; 1951 else if (NewVD->getStorageClass() == VarDecl::Static) 1952 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1953 << SizeRange; 1954 else 1955 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1956 << SizeRange; 1957 return NewVD->setInvalidDecl(); 1958 } 1959 1960 if (FixedTy.isNull()) { 1961 if (NewVD->isFileVarDecl()) 1962 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1963 else 1964 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1965 return NewVD->setInvalidDecl(); 1966 } 1967 1968 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1969 NewVD->setType(FixedTy); 1970 } 1971 1972 if (!PrevDecl && NewVD->isExternC(Context)) { 1973 // Since we did not find anything by this name and we're declaring 1974 // an extern "C" variable, look for a non-visible extern "C" 1975 // declaration with the same name. 1976 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1977 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1978 if (Pos != LocallyScopedExternalDecls.end()) 1979 PrevDecl = Pos->second; 1980 } 1981 1982 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1983 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1984 << T; 1985 return NewVD->setInvalidDecl(); 1986 } 1987 1988 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>(Context)) { 1989 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 1990 return NewVD->setInvalidDecl(); 1991 } 1992 1993 if (isVM && NewVD->hasAttr<BlocksAttr>(Context)) { 1994 Diag(NewVD->getLocation(), diag::err_block_on_vm); 1995 return NewVD->setInvalidDecl(); 1996 } 1997 1998 if (PrevDecl) { 1999 Redeclaration = true; 2000 MergeVarDecl(NewVD, PrevDecl); 2001 } 2002} 2003 2004NamedDecl* 2005Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2006 QualType R, NamedDecl* PrevDecl, 2007 MultiTemplateParamsArg TemplateParamLists, 2008 bool IsFunctionDefinition, bool &Redeclaration) { 2009 assert(R.getTypePtr()->isFunctionType()); 2010 2011 DeclarationName Name = GetNameForDeclarator(D); 2012 FunctionDecl::StorageClass SC = FunctionDecl::None; 2013 switch (D.getDeclSpec().getStorageClassSpec()) { 2014 default: assert(0 && "Unknown storage class!"); 2015 case DeclSpec::SCS_auto: 2016 case DeclSpec::SCS_register: 2017 case DeclSpec::SCS_mutable: 2018 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2019 diag::err_typecheck_sclass_func); 2020 D.setInvalidType(); 2021 break; 2022 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2023 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2024 case DeclSpec::SCS_static: { 2025 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2026 // C99 6.7.1p5: 2027 // The declaration of an identifier for a function that has 2028 // block scope shall have no explicit storage-class specifier 2029 // other than extern 2030 // See also (C++ [dcl.stc]p4). 2031 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2032 diag::err_static_block_func); 2033 SC = FunctionDecl::None; 2034 } else 2035 SC = FunctionDecl::Static; 2036 break; 2037 } 2038 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2039 } 2040 2041 if (D.getDeclSpec().isThreadSpecified()) 2042 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2043 2044 bool isInline = D.getDeclSpec().isInlineSpecified(); 2045 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2046 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2047 2048 // Check that the return type is not an abstract class type. 2049 // For record types, this is done by the AbstractClassUsageDiagnoser once 2050 // the class has been completely parsed. 2051 if (!DC->isRecord() && 2052 RequireNonAbstractType(D.getIdentifierLoc(), 2053 R->getAsFunctionType()->getResultType(), 2054 diag::err_abstract_type_in_decl, 2055 AbstractReturnType)) 2056 D.setInvalidType(); 2057 2058 // Do not allow returning a objc interface by-value. 2059 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2060 Diag(D.getIdentifierLoc(), 2061 diag::err_object_cannot_be_passed_returned_by_value) << 0 2062 << R->getAsFunctionType()->getResultType(); 2063 D.setInvalidType(); 2064 } 2065 2066 // Check that we can declare a template here. 2067 if (TemplateParamLists.size() && 2068 CheckTemplateDeclScope(S, TemplateParamLists)) 2069 return 0; 2070 2071 bool isVirtualOkay = false; 2072 FunctionDecl *NewFD; 2073 if (D.getKind() == Declarator::DK_Constructor) { 2074 // This is a C++ constructor declaration. 2075 assert(DC->isRecord() && 2076 "Constructors can only be declared in a member context"); 2077 2078 R = CheckConstructorDeclarator(D, R, SC); 2079 2080 // Create the new declaration 2081 NewFD = CXXConstructorDecl::Create(Context, 2082 cast<CXXRecordDecl>(DC), 2083 D.getIdentifierLoc(), Name, R, 2084 isExplicit, isInline, 2085 /*isImplicitlyDeclared=*/false); 2086 } else if (D.getKind() == Declarator::DK_Destructor) { 2087 // This is a C++ destructor declaration. 2088 if (DC->isRecord()) { 2089 R = CheckDestructorDeclarator(D, SC); 2090 2091 NewFD = CXXDestructorDecl::Create(Context, 2092 cast<CXXRecordDecl>(DC), 2093 D.getIdentifierLoc(), Name, R, 2094 isInline, 2095 /*isImplicitlyDeclared=*/false); 2096 2097 isVirtualOkay = true; 2098 } else { 2099 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2100 2101 // Create a FunctionDecl to satisfy the function definition parsing 2102 // code path. 2103 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2104 Name, R, SC, isInline, 2105 /*hasPrototype=*/true, 2106 // FIXME: Move to DeclGroup... 2107 D.getDeclSpec().getSourceRange().getBegin()); 2108 D.setInvalidType(); 2109 } 2110 } else if (D.getKind() == Declarator::DK_Conversion) { 2111 if (!DC->isRecord()) { 2112 Diag(D.getIdentifierLoc(), 2113 diag::err_conv_function_not_member); 2114 return 0; 2115 } 2116 2117 CheckConversionDeclarator(D, R, SC); 2118 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2119 D.getIdentifierLoc(), Name, R, 2120 isInline, isExplicit); 2121 2122 isVirtualOkay = true; 2123 } else if (DC->isRecord()) { 2124 // If the of the function is the same as the name of the record, then this 2125 // must be an invalid constructor that has a return type. 2126 // (The parser checks for a return type and makes the declarator a 2127 // constructor if it has no return type). 2128 // must have an invalid constructor that has a return type 2129 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2130 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2131 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2132 << SourceRange(D.getIdentifierLoc()); 2133 return 0; 2134 } 2135 2136 // This is a C++ method declaration. 2137 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2138 D.getIdentifierLoc(), Name, R, 2139 (SC == FunctionDecl::Static), isInline); 2140 2141 isVirtualOkay = (SC != FunctionDecl::Static); 2142 } else { 2143 // Determine whether the function was written with a 2144 // prototype. This true when: 2145 // - we're in C++ (where every function has a prototype), 2146 // - there is a prototype in the declarator, or 2147 // - the type R of the function is some kind of typedef or other reference 2148 // to a type name (which eventually refers to a function type). 2149 bool HasPrototype = 2150 getLangOptions().CPlusPlus || 2151 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2152 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2153 2154 NewFD = FunctionDecl::Create(Context, DC, 2155 D.getIdentifierLoc(), 2156 Name, R, SC, isInline, HasPrototype, 2157 // FIXME: Move to DeclGroup... 2158 D.getDeclSpec().getSourceRange().getBegin()); 2159 } 2160 2161 if (D.isInvalidType()) 2162 NewFD->setInvalidDecl(); 2163 2164 // Set the lexical context. If the declarator has a C++ 2165 // scope specifier, the lexical context will be different 2166 // from the semantic context. 2167 NewFD->setLexicalDeclContext(CurContext); 2168 2169 // If there is a template parameter list, then we are dealing with a 2170 // template declaration or specialization. 2171 FunctionTemplateDecl *FunctionTemplate = 0; 2172 if (TemplateParamLists.size()) { 2173 // FIXME: member templates! 2174 TemplateParameterList *TemplateParams 2175 = static_cast<TemplateParameterList *>(*TemplateParamLists.release()); 2176 2177 if (TemplateParams->size() > 0) { 2178 // This is a function template 2179 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2180 NewFD->getLocation(), 2181 Name, TemplateParams, 2182 NewFD); 2183 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2184 } else { 2185 // FIXME: Handle function template specializations 2186 } 2187 } 2188 2189 // C++ [dcl.fct.spec]p5: 2190 // The virtual specifier shall only be used in declarations of 2191 // nonstatic class member functions that appear within a 2192 // member-specification of a class declaration; see 10.3. 2193 // 2194 if (isVirtual && !NewFD->isInvalidDecl()) { 2195 if (!isVirtualOkay) { 2196 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2197 diag::err_virtual_non_function); 2198 } else if (!CurContext->isRecord()) { 2199 // 'virtual' was specified outside of the class. 2200 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2201 << CodeModificationHint::CreateRemoval( 2202 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2203 } else { 2204 // Okay: Add virtual to the method. 2205 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2206 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2207 CurClass->setAggregate(false); 2208 CurClass->setPOD(false); 2209 CurClass->setPolymorphic(true); 2210 CurClass->setHasTrivialConstructor(false); 2211 } 2212 } 2213 2214 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2215 // Look for virtual methods in base classes that this method might override. 2216 2217 BasePaths Paths; 2218 if (LookupInBases(cast<CXXRecordDecl>(DC), 2219 MemberLookupCriteria(NewMD), Paths)) { 2220 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2221 E = Paths.found_decls_end(); I != E; ++I) { 2222 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2223 if (!CheckOverridingFunctionReturnType(NewMD, OldMD)) 2224 NewMD->addOverriddenMethod(OldMD); 2225 } 2226 } 2227 } 2228 } 2229 2230 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2231 !CurContext->isRecord()) { 2232 // C++ [class.static]p1: 2233 // A data or function member of a class may be declared static 2234 // in a class definition, in which case it is a static member of 2235 // the class. 2236 2237 // Complain about the 'static' specifier if it's on an out-of-line 2238 // member function definition. 2239 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2240 diag::err_static_out_of_line) 2241 << CodeModificationHint::CreateRemoval( 2242 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2243 } 2244 2245 // Handle GNU asm-label extension (encoded as an attribute). 2246 if (Expr *E = (Expr*) D.getAsmLabel()) { 2247 // The parser guarantees this is a string. 2248 StringLiteral *SE = cast<StringLiteral>(E); 2249 NewFD->addAttr(Context, 2250 ::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2251 SE->getByteLength()))); 2252 } 2253 2254 // Copy the parameter declarations from the declarator D to the function 2255 // declaration NewFD, if they are available. First scavenge them into Params. 2256 llvm::SmallVector<ParmVarDecl*, 16> Params; 2257 if (D.getNumTypeObjects() > 0) { 2258 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2259 2260 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2261 // function that takes no arguments, not a function that takes a 2262 // single void argument. 2263 // We let through "const void" here because Sema::GetTypeForDeclarator 2264 // already checks for that case. 2265 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2266 FTI.ArgInfo[0].Param && 2267 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2268 // Empty arg list, don't push any params. 2269 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2270 2271 // In C++, the empty parameter-type-list must be spelled "void"; a 2272 // typedef of void is not permitted. 2273 if (getLangOptions().CPlusPlus && 2274 Param->getType().getUnqualifiedType() != Context.VoidTy) 2275 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2276 // FIXME: Leaks decl? 2277 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2278 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2279 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2280 } 2281 2282 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2283 // When we're declaring a function with a typedef, typeof, etc as in the 2284 // following example, we'll need to synthesize (unnamed) 2285 // parameters for use in the declaration. 2286 // 2287 // @code 2288 // typedef void fn(int); 2289 // fn f; 2290 // @endcode 2291 2292 // Synthesize a parameter for each argument type. 2293 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2294 AE = FT->arg_type_end(); AI != AE; ++AI) { 2295 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2296 SourceLocation(), 0, 2297 *AI, VarDecl::None, 0); 2298 Param->setImplicit(); 2299 Params.push_back(Param); 2300 } 2301 } else { 2302 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2303 "Should not need args for typedef of non-prototype fn"); 2304 } 2305 // Finally, we know we have the right number of parameters, install them. 2306 NewFD->setParams(Context, Params.data(), Params.size()); 2307 2308 2309 2310 // If name lookup finds a previous declaration that is not in the 2311 // same scope as the new declaration, this may still be an 2312 // acceptable redeclaration. 2313 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2314 !(NewFD->hasLinkage() && 2315 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2316 PrevDecl = 0; 2317 2318 // Perform semantic checking on the function declaration. 2319 bool OverloadableAttrRequired = false; // FIXME: HACK! 2320 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2321 /*FIXME:*/OverloadableAttrRequired); 2322 2323 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2324 // An out-of-line member function declaration must also be a 2325 // definition (C++ [dcl.meaning]p1). 2326 if (!IsFunctionDefinition) { 2327 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2328 << D.getCXXScopeSpec().getRange(); 2329 NewFD->setInvalidDecl(); 2330 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2331 // The user tried to provide an out-of-line definition for a 2332 // function that is a member of a class or namespace, but there 2333 // was no such member function declared (C++ [class.mfct]p2, 2334 // C++ [namespace.memdef]p2). For example: 2335 // 2336 // class X { 2337 // void f() const; 2338 // }; 2339 // 2340 // void X::f() { } // ill-formed 2341 // 2342 // Complain about this problem, and attempt to suggest close 2343 // matches (e.g., those that differ only in cv-qualifiers and 2344 // whether the parameter types are references). 2345 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2346 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2347 NewFD->setInvalidDecl(); 2348 2349 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2350 true); 2351 assert(!Prev.isAmbiguous() && 2352 "Cannot have an ambiguity in previous-declaration lookup"); 2353 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2354 Func != FuncEnd; ++Func) { 2355 if (isa<FunctionDecl>(*Func) && 2356 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2357 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2358 } 2359 2360 PrevDecl = 0; 2361 } 2362 } 2363 2364 // Handle attributes. We need to have merged decls when handling attributes 2365 // (for example to check for conflicts, etc). 2366 // FIXME: This needs to happen before we merge declarations. Then, 2367 // let attribute merging cope with attribute conflicts. 2368 ProcessDeclAttributes(S, NewFD, D); 2369 AddKnownFunctionAttributes(NewFD); 2370 2371 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>(Context)) { 2372 // If a function name is overloadable in C, then every function 2373 // with that name must be marked "overloadable". 2374 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2375 << Redeclaration << NewFD; 2376 if (PrevDecl) 2377 Diag(PrevDecl->getLocation(), 2378 diag::note_attribute_overloadable_prev_overload); 2379 NewFD->addAttr(Context, ::new (Context) OverloadableAttr()); 2380 } 2381 2382 // If this is a locally-scoped extern C function, update the 2383 // map of such names. 2384 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2385 && !NewFD->isInvalidDecl()) 2386 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2387 2388 // Set this FunctionDecl's range up to the right paren. 2389 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2390 2391 return NewFD; 2392} 2393 2394/// \brief Perform semantic checking of a new function declaration. 2395/// 2396/// Performs semantic analysis of the new function declaration 2397/// NewFD. This routine performs all semantic checking that does not 2398/// require the actual declarator involved in the declaration, and is 2399/// used both for the declaration of functions as they are parsed 2400/// (called via ActOnDeclarator) and for the declaration of functions 2401/// that have been instantiated via C++ template instantiation (called 2402/// via InstantiateDecl). 2403/// 2404/// This sets NewFD->isInvalidDecl() to true if there was an error. 2405void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2406 bool &Redeclaration, 2407 bool &OverloadableAttrRequired) { 2408 // If NewFD is already known erroneous, don't do any of this checking. 2409 if (NewFD->isInvalidDecl()) 2410 return; 2411 2412 if (NewFD->getResultType()->isVariablyModifiedType()) { 2413 // Functions returning a variably modified type violate C99 6.7.5.2p2 2414 // because all functions have linkage. 2415 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2416 return NewFD->setInvalidDecl(); 2417 } 2418 2419 // Semantic checking for this function declaration (in isolation). 2420 if (getLangOptions().CPlusPlus) { 2421 // C++-specific checks. 2422 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2423 CheckConstructor(Constructor); 2424 } else if (isa<CXXDestructorDecl>(NewFD)) { 2425 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2426 Record->setUserDeclaredDestructor(true); 2427 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2428 // user-defined destructor. 2429 Record->setPOD(false); 2430 2431 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2432 // declared destructor. 2433 Record->setHasTrivialDestructor(false); 2434 } else if (CXXConversionDecl *Conversion 2435 = dyn_cast<CXXConversionDecl>(NewFD)) 2436 ActOnConversionDeclarator(Conversion); 2437 2438 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2439 if (NewFD->isOverloadedOperator() && 2440 CheckOverloadedOperatorDeclaration(NewFD)) 2441 return NewFD->setInvalidDecl(); 2442 } 2443 2444 // C99 6.7.4p6: 2445 // [... ] For a function with external linkage, the following 2446 // restrictions apply: [...] If all of the file scope declarations 2447 // for a function in a translation unit include the inline 2448 // function specifier without extern, then the definition in that 2449 // translation unit is an inline definition. An inline definition 2450 // does not provide an external definition for the function, and 2451 // does not forbid an external definition in another translation 2452 // unit. 2453 // 2454 // Here we determine whether this function, in isolation, would be a 2455 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2456 // previous declarations. 2457 if (NewFD->isInline() && getLangOptions().C99 && 2458 NewFD->getStorageClass() == FunctionDecl::None && 2459 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2460 NewFD->setC99InlineDefinition(true); 2461 2462 // Check for a previous declaration of this name. 2463 if (!PrevDecl && NewFD->isExternC(Context)) { 2464 // Since we did not find anything by this name and we're declaring 2465 // an extern "C" function, look for a non-visible extern "C" 2466 // declaration with the same name. 2467 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2468 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2469 if (Pos != LocallyScopedExternalDecls.end()) 2470 PrevDecl = Pos->second; 2471 } 2472 2473 // Merge or overload the declaration with an existing declaration of 2474 // the same name, if appropriate. 2475 if (PrevDecl) { 2476 // Determine whether NewFD is an overload of PrevDecl or 2477 // a declaration that requires merging. If it's an overload, 2478 // there's no more work to do here; we'll just add the new 2479 // function to the scope. 2480 OverloadedFunctionDecl::function_iterator MatchedDecl; 2481 2482 if (!getLangOptions().CPlusPlus && 2483 AllowOverloadingOfFunction(PrevDecl, Context)) { 2484 OverloadableAttrRequired = true; 2485 2486 // Functions marked "overloadable" must have a prototype (that 2487 // we can't get through declaration merging). 2488 if (!NewFD->getType()->getAsFunctionProtoType()) { 2489 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2490 << NewFD; 2491 Redeclaration = true; 2492 2493 // Turn this into a variadic function with no parameters. 2494 QualType R = Context.getFunctionType( 2495 NewFD->getType()->getAsFunctionType()->getResultType(), 2496 0, 0, true, 0); 2497 NewFD->setType(R); 2498 return NewFD->setInvalidDecl(); 2499 } 2500 } 2501 2502 if (PrevDecl && 2503 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2504 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2505 !isa<UsingDecl>(PrevDecl)) { 2506 Redeclaration = true; 2507 Decl *OldDecl = PrevDecl; 2508 2509 // If PrevDecl was an overloaded function, extract the 2510 // FunctionDecl that matched. 2511 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2512 OldDecl = *MatchedDecl; 2513 2514 // NewFD and OldDecl represent declarations that need to be 2515 // merged. 2516 if (MergeFunctionDecl(NewFD, OldDecl)) 2517 return NewFD->setInvalidDecl(); 2518 2519 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2520 } 2521 } 2522 2523 // In C++, check default arguments now that we have merged decls. Unless 2524 // the lexical context is the class, because in this case this is done 2525 // during delayed parsing anyway. 2526 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2527 CheckCXXDefaultArguments(NewFD); 2528} 2529 2530bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2531 // FIXME: Need strict checking. In C89, we need to check for 2532 // any assignment, increment, decrement, function-calls, or 2533 // commas outside of a sizeof. In C99, it's the same list, 2534 // except that the aforementioned are allowed in unevaluated 2535 // expressions. Everything else falls under the 2536 // "may accept other forms of constant expressions" exception. 2537 // (We never end up here for C++, so the constant expression 2538 // rules there don't matter.) 2539 if (Init->isConstantInitializer(Context)) 2540 return false; 2541 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2542 << Init->getSourceRange(); 2543 return true; 2544} 2545 2546void Sema::AddInitializerToDecl(DeclPtrTy dcl, FullExprArg init) { 2547 AddInitializerToDecl(dcl, init.release(), /*DirectInit=*/false); 2548} 2549 2550/// AddInitializerToDecl - Adds the initializer Init to the 2551/// declaration dcl. If DirectInit is true, this is C++ direct 2552/// initialization rather than copy initialization. 2553void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2554 Decl *RealDecl = dcl.getAs<Decl>(); 2555 // If there is no declaration, there was an error parsing it. Just ignore 2556 // the initializer. 2557 if (RealDecl == 0) 2558 return; 2559 2560 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2561 // With declarators parsed the way they are, the parser cannot 2562 // distinguish between a normal initializer and a pure-specifier. 2563 // Thus this grotesque test. 2564 IntegerLiteral *IL; 2565 Expr *Init = static_cast<Expr *>(init.get()); 2566 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2567 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2568 if (Method->isVirtualAsWritten()) { 2569 Method->setPure(); 2570 2571 // A class is abstract if at least one function is pure virtual. 2572 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2573 } else if (!Method->isInvalidDecl()) { 2574 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2575 << Method->getDeclName() << Init->getSourceRange(); 2576 Method->setInvalidDecl(); 2577 } 2578 } else { 2579 Diag(Method->getLocation(), diag::err_member_function_initialization) 2580 << Method->getDeclName() << Init->getSourceRange(); 2581 Method->setInvalidDecl(); 2582 } 2583 return; 2584 } 2585 2586 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2587 if (!VDecl) { 2588 if (getLangOptions().CPlusPlus && 2589 RealDecl->getLexicalDeclContext()->isRecord() && 2590 isa<NamedDecl>(RealDecl)) 2591 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2592 << cast<NamedDecl>(RealDecl)->getDeclName(); 2593 else 2594 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2595 RealDecl->setInvalidDecl(); 2596 return; 2597 } 2598 2599 if (!VDecl->getType()->isArrayType() && 2600 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2601 diag::err_typecheck_decl_incomplete_type)) { 2602 RealDecl->setInvalidDecl(); 2603 return; 2604 } 2605 2606 const VarDecl *Def = 0; 2607 if (VDecl->getDefinition(Def)) { 2608 Diag(VDecl->getLocation(), diag::err_redefinition) 2609 << VDecl->getDeclName(); 2610 Diag(Def->getLocation(), diag::note_previous_definition); 2611 VDecl->setInvalidDecl(); 2612 return; 2613 } 2614 2615 // Take ownership of the expression, now that we're sure we have somewhere 2616 // to put it. 2617 Expr *Init = init.takeAs<Expr>(); 2618 assert(Init && "missing initializer"); 2619 2620 // Get the decls type and save a reference for later, since 2621 // CheckInitializerTypes may change it. 2622 QualType DclT = VDecl->getType(), SavT = DclT; 2623 if (VDecl->isBlockVarDecl()) { 2624 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2625 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2626 VDecl->setInvalidDecl(); 2627 } else if (!VDecl->isInvalidDecl()) { 2628 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2629 VDecl->getDeclName(), DirectInit)) 2630 VDecl->setInvalidDecl(); 2631 2632 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2633 // Don't check invalid declarations to avoid emitting useless diagnostics. 2634 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2635 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2636 CheckForConstantInitializer(Init, DclT); 2637 } 2638 } 2639 } else if (VDecl->isStaticDataMember() && 2640 VDecl->getLexicalDeclContext()->isRecord()) { 2641 // This is an in-class initialization for a static data member, e.g., 2642 // 2643 // struct S { 2644 // static const int value = 17; 2645 // }; 2646 2647 // Attach the initializer 2648 VDecl->setInit(Context, Init); 2649 2650 // C++ [class.mem]p4: 2651 // A member-declarator can contain a constant-initializer only 2652 // if it declares a static member (9.4) of const integral or 2653 // const enumeration type, see 9.4.2. 2654 QualType T = VDecl->getType(); 2655 if (!T->isDependentType() && 2656 (!Context.getCanonicalType(T).isConstQualified() || 2657 !T->isIntegralType())) { 2658 Diag(VDecl->getLocation(), diag::err_member_initialization) 2659 << VDecl->getDeclName() << Init->getSourceRange(); 2660 VDecl->setInvalidDecl(); 2661 } else { 2662 // C++ [class.static.data]p4: 2663 // If a static data member is of const integral or const 2664 // enumeration type, its declaration in the class definition 2665 // can specify a constant-initializer which shall be an 2666 // integral constant expression (5.19). 2667 if (!Init->isTypeDependent() && 2668 !Init->getType()->isIntegralType()) { 2669 // We have a non-dependent, non-integral or enumeration type. 2670 Diag(Init->getSourceRange().getBegin(), 2671 diag::err_in_class_initializer_non_integral_type) 2672 << Init->getType() << Init->getSourceRange(); 2673 VDecl->setInvalidDecl(); 2674 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2675 // Check whether the expression is a constant expression. 2676 llvm::APSInt Value; 2677 SourceLocation Loc; 2678 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2679 Diag(Loc, diag::err_in_class_initializer_non_constant) 2680 << Init->getSourceRange(); 2681 VDecl->setInvalidDecl(); 2682 } else if (!VDecl->getType()->isDependentType()) 2683 ImpCastExprToType(Init, VDecl->getType()); 2684 } 2685 } 2686 } else if (VDecl->isFileVarDecl()) { 2687 if (VDecl->getStorageClass() == VarDecl::Extern) 2688 Diag(VDecl->getLocation(), diag::warn_extern_init); 2689 if (!VDecl->isInvalidDecl()) 2690 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2691 VDecl->getDeclName(), DirectInit)) 2692 VDecl->setInvalidDecl(); 2693 2694 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2695 // Don't check invalid declarations to avoid emitting useless diagnostics. 2696 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2697 // C99 6.7.8p4. All file scoped initializers need to be constant. 2698 CheckForConstantInitializer(Init, DclT); 2699 } 2700 } 2701 // If the type changed, it means we had an incomplete type that was 2702 // completed by the initializer. For example: 2703 // int ary[] = { 1, 3, 5 }; 2704 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2705 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2706 VDecl->setType(DclT); 2707 Init->setType(DclT); 2708 } 2709 2710 // Attach the initializer to the decl. 2711 VDecl->setInit(Context, Init); 2712 2713 // If the previous declaration of VDecl was a tentative definition, 2714 // remove it from the set of tentative definitions. 2715 if (VDecl->getPreviousDeclaration() && 2716 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2717 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2718 = TentativeDefinitions.find(VDecl->getDeclName()); 2719 assert(Pos != TentativeDefinitions.end() && 2720 "Unrecorded tentative definition?"); 2721 TentativeDefinitions.erase(Pos); 2722 } 2723 2724 return; 2725} 2726 2727void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2728 Decl *RealDecl = dcl.getAs<Decl>(); 2729 2730 // If there is no declaration, there was an error parsing it. Just ignore it. 2731 if (RealDecl == 0) 2732 return; 2733 2734 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2735 QualType Type = Var->getType(); 2736 2737 // Record tentative definitions. 2738 if (Var->isTentativeDefinition(Context)) 2739 TentativeDefinitions[Var->getDeclName()] = Var; 2740 2741 // C++ [dcl.init.ref]p3: 2742 // The initializer can be omitted for a reference only in a 2743 // parameter declaration (8.3.5), in the declaration of a 2744 // function return type, in the declaration of a class member 2745 // within its class declaration (9.2), and where the extern 2746 // specifier is explicitly used. 2747 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2748 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2749 << Var->getDeclName() 2750 << SourceRange(Var->getLocation(), Var->getLocation()); 2751 Var->setInvalidDecl(); 2752 return; 2753 } 2754 2755 // C++ [dcl.init]p9: 2756 // 2757 // If no initializer is specified for an object, and the object 2758 // is of (possibly cv-qualified) non-POD class type (or array 2759 // thereof), the object shall be default-initialized; if the 2760 // object is of const-qualified type, the underlying class type 2761 // shall have a user-declared default constructor. 2762 if (getLangOptions().CPlusPlus) { 2763 QualType InitType = Type; 2764 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2765 InitType = Array->getElementType(); 2766 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 2767 InitType->isRecordType() && !InitType->isDependentType()) { 2768 CXXRecordDecl *RD = 2769 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2770 CXXConstructorDecl *Constructor = 0; 2771 if (!RequireCompleteType(Var->getLocation(), InitType, 2772 diag::err_invalid_incomplete_type_use)) 2773 Constructor 2774 = PerformInitializationByConstructor(InitType, 0, 0, 2775 Var->getLocation(), 2776 SourceRange(Var->getLocation(), 2777 Var->getLocation()), 2778 Var->getDeclName(), 2779 IK_Default); 2780 if (!Constructor) 2781 Var->setInvalidDecl(); 2782 else 2783 if (!RD->hasTrivialConstructor()) 2784 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2785 } 2786 } 2787 2788#if 0 2789 // FIXME: Temporarily disabled because we are not properly parsing 2790 // linkage specifications on declarations, e.g., 2791 // 2792 // extern "C" const CGPoint CGPointerZero; 2793 // 2794 // C++ [dcl.init]p9: 2795 // 2796 // If no initializer is specified for an object, and the 2797 // object is of (possibly cv-qualified) non-POD class type (or 2798 // array thereof), the object shall be default-initialized; if 2799 // the object is of const-qualified type, the underlying class 2800 // type shall have a user-declared default 2801 // constructor. Otherwise, if no initializer is specified for 2802 // an object, the object and its subobjects, if any, have an 2803 // indeterminate initial value; if the object or any of its 2804 // subobjects are of const-qualified type, the program is 2805 // ill-formed. 2806 // 2807 // This isn't technically an error in C, so we don't diagnose it. 2808 // 2809 // FIXME: Actually perform the POD/user-defined default 2810 // constructor check. 2811 if (getLangOptions().CPlusPlus && 2812 Context.getCanonicalType(Type).isConstQualified() && 2813 !Var->hasExternalStorage()) 2814 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2815 << Var->getName() 2816 << SourceRange(Var->getLocation(), Var->getLocation()); 2817#endif 2818 } 2819} 2820 2821Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 2822 DeclPtrTy *Group, 2823 unsigned NumDecls) { 2824 llvm::SmallVector<Decl*, 8> Decls; 2825 2826 if (DS.isTypeSpecOwned()) 2827 Decls.push_back((Decl*)DS.getTypeRep()); 2828 2829 for (unsigned i = 0; i != NumDecls; ++i) 2830 if (Decl *D = Group[i].getAs<Decl>()) 2831 Decls.push_back(D); 2832 2833 // Perform semantic analysis that depends on having fully processed both 2834 // the declarator and initializer. 2835 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2836 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2837 if (!IDecl) 2838 continue; 2839 QualType T = IDecl->getType(); 2840 2841 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2842 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2843 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2844 if (!IDecl->isInvalidDecl() && 2845 RequireCompleteType(IDecl->getLocation(), T, 2846 diag::err_typecheck_decl_incomplete_type)) 2847 IDecl->setInvalidDecl(); 2848 } 2849 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2850 // object that has file scope without an initializer, and without a 2851 // storage-class specifier or with the storage-class specifier "static", 2852 // constitutes a tentative definition. Note: A tentative definition with 2853 // external linkage is valid (C99 6.2.2p5). 2854 if (IDecl->isTentativeDefinition(Context)) { 2855 QualType CheckType = T; 2856 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2857 2858 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2859 if (ArrayT) { 2860 CheckType = ArrayT->getElementType(); 2861 DiagID = diag::err_illegal_decl_array_incomplete_type; 2862 } 2863 2864 if (IDecl->isInvalidDecl()) { 2865 // Do nothing with invalid declarations 2866 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2867 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2868 // C99 6.9.2p3: If the declaration of an identifier for an object is 2869 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2870 // declared type shall not be an incomplete type. 2871 IDecl->setInvalidDecl(); 2872 } 2873 } 2874 } 2875 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2876 Decls.data(), Decls.size())); 2877} 2878 2879 2880/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2881/// to introduce parameters into function prototype scope. 2882Sema::DeclPtrTy 2883Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2884 const DeclSpec &DS = D.getDeclSpec(); 2885 2886 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2887 VarDecl::StorageClass StorageClass = VarDecl::None; 2888 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2889 StorageClass = VarDecl::Register; 2890 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2891 Diag(DS.getStorageClassSpecLoc(), 2892 diag::err_invalid_storage_class_in_func_decl); 2893 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2894 } 2895 2896 if (D.getDeclSpec().isThreadSpecified()) 2897 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2898 2899 DiagnoseFunctionSpecifiers(D); 2900 2901 // Check that there are no default arguments inside the type of this 2902 // parameter (C++ only). 2903 if (getLangOptions().CPlusPlus) 2904 CheckExtraCXXDefaultArguments(D); 2905 2906 TagDecl *OwnedDecl = 0; 2907 QualType parmDeclType = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedDecl); 2908 2909 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 2910 // C++ [dcl.fct]p6: 2911 // Types shall not be defined in return or parameter types. 2912 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 2913 << Context.getTypeDeclType(OwnedDecl); 2914 } 2915 2916 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2917 // Can this happen for params? We already checked that they don't conflict 2918 // among each other. Here they can only shadow globals, which is ok. 2919 IdentifierInfo *II = D.getIdentifier(); 2920 if (II) { 2921 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2922 if (PrevDecl->isTemplateParameter()) { 2923 // Maybe we will complain about the shadowed template parameter. 2924 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2925 // Just pretend that we didn't see the previous declaration. 2926 PrevDecl = 0; 2927 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2928 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2929 2930 // Recover by removing the name 2931 II = 0; 2932 D.SetIdentifier(0, D.getIdentifierLoc()); 2933 } 2934 } 2935 } 2936 2937 // Parameters can not be abstract class types. 2938 // For record types, this is done by the AbstractClassUsageDiagnoser once 2939 // the class has been completely parsed. 2940 if (!CurContext->isRecord() && 2941 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2942 diag::err_abstract_type_in_decl, 2943 AbstractParamType)) 2944 D.setInvalidType(true); 2945 2946 QualType T = adjustParameterType(parmDeclType); 2947 2948 ParmVarDecl *New; 2949 if (T == parmDeclType) // parameter type did not need adjustment 2950 New = ParmVarDecl::Create(Context, CurContext, 2951 D.getIdentifierLoc(), II, 2952 parmDeclType, StorageClass, 2953 0); 2954 else // keep track of both the adjusted and unadjusted types 2955 New = OriginalParmVarDecl::Create(Context, CurContext, 2956 D.getIdentifierLoc(), II, T, 2957 parmDeclType, StorageClass, 0); 2958 2959 if (D.isInvalidType()) 2960 New->setInvalidDecl(); 2961 2962 // Parameter declarators cannot be interface types. All ObjC objects are 2963 // passed by reference. 2964 if (T->isObjCInterfaceType()) { 2965 Diag(D.getIdentifierLoc(), 2966 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2967 New->setInvalidDecl(); 2968 } 2969 2970 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2971 if (D.getCXXScopeSpec().isSet()) { 2972 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2973 << D.getCXXScopeSpec().getRange(); 2974 New->setInvalidDecl(); 2975 } 2976 2977 // Add the parameter declaration into this scope. 2978 S->AddDecl(DeclPtrTy::make(New)); 2979 if (II) 2980 IdResolver.AddDecl(New); 2981 2982 ProcessDeclAttributes(S, New, D); 2983 2984 if (New->hasAttr<BlocksAttr>(Context)) { 2985 Diag(New->getLocation(), diag::err_block_on_nonlocal); 2986 } 2987 return DeclPtrTy::make(New); 2988} 2989 2990void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2991 SourceLocation LocAfterDecls) { 2992 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2993 "Not a function declarator!"); 2994 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2995 2996 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2997 // for a K&R function. 2998 if (!FTI.hasPrototype) { 2999 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3000 --i; 3001 if (FTI.ArgInfo[i].Param == 0) { 3002 std::string Code = " int "; 3003 Code += FTI.ArgInfo[i].Ident->getName(); 3004 Code += ";\n"; 3005 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3006 << FTI.ArgInfo[i].Ident 3007 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3008 3009 // Implicitly declare the argument as type 'int' for lack of a better 3010 // type. 3011 DeclSpec DS; 3012 const char* PrevSpec; // unused 3013 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3014 PrevSpec); 3015 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3016 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3017 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3018 } 3019 } 3020 } 3021} 3022 3023Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3024 Declarator &D) { 3025 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3026 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3027 "Not a function declarator!"); 3028 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3029 3030 if (FTI.hasPrototype) { 3031 // FIXME: Diagnose arguments without names in C. 3032 } 3033 3034 Scope *ParentScope = FnBodyScope->getParent(); 3035 3036 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3037 MultiTemplateParamsArg(*this), 3038 /*IsFunctionDefinition=*/true); 3039 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3040} 3041 3042Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3043 if (!D) 3044 return D; 3045 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 3046 3047 CurFunctionNeedsScopeChecking = false; 3048 3049 // See if this is a redefinition. 3050 const FunctionDecl *Definition; 3051 if (FD->getBody(Context, Definition)) { 3052 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3053 Diag(Definition->getLocation(), diag::note_previous_definition); 3054 } 3055 3056 // Builtin functions cannot be defined. 3057 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3058 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3059 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3060 FD->setInvalidDecl(); 3061 } 3062 } 3063 3064 // The return type of a function definition must be complete 3065 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3066 QualType ResultType = FD->getResultType(); 3067 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3068 !FD->isInvalidDecl() && 3069 RequireCompleteType(FD->getLocation(), ResultType, 3070 diag::err_func_def_incomplete_result)) 3071 FD->setInvalidDecl(); 3072 3073 // GNU warning -Wmissing-prototypes: 3074 // Warn if a global function is defined without a previous 3075 // prototype declaration. This warning is issued even if the 3076 // definition itself provides a prototype. The aim is to detect 3077 // global functions that fail to be declared in header files. 3078 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3079 !FD->isMain()) { 3080 bool MissingPrototype = true; 3081 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3082 Prev; Prev = Prev->getPreviousDeclaration()) { 3083 // Ignore any declarations that occur in function or method 3084 // scope, because they aren't visible from the header. 3085 if (Prev->getDeclContext()->isFunctionOrMethod()) 3086 continue; 3087 3088 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3089 break; 3090 } 3091 3092 if (MissingPrototype) 3093 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3094 } 3095 3096 if (FnBodyScope) 3097 PushDeclContext(FnBodyScope, FD); 3098 3099 // Check the validity of our function parameters 3100 CheckParmsForFunctionDef(FD); 3101 3102 // Introduce our parameters into the function scope 3103 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3104 ParmVarDecl *Param = FD->getParamDecl(p); 3105 Param->setOwningFunction(FD); 3106 3107 // If this has an identifier, add it to the scope stack. 3108 if (Param->getIdentifier() && FnBodyScope) 3109 PushOnScopeChains(Param, FnBodyScope); 3110 } 3111 3112 // Checking attributes of current function definition 3113 // dllimport attribute. 3114 if (FD->getAttr<DLLImportAttr>(Context) && 3115 (!FD->getAttr<DLLExportAttr>(Context))) { 3116 // dllimport attribute cannot be applied to definition. 3117 if (!(FD->getAttr<DLLImportAttr>(Context))->isInherited()) { 3118 Diag(FD->getLocation(), 3119 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3120 << "dllimport"; 3121 FD->setInvalidDecl(); 3122 return DeclPtrTy::make(FD); 3123 } else { 3124 // If a symbol previously declared dllimport is later defined, the 3125 // attribute is ignored in subsequent references, and a warning is 3126 // emitted. 3127 Diag(FD->getLocation(), 3128 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3129 << FD->getNameAsCString() << "dllimport"; 3130 } 3131 } 3132 return DeclPtrTy::make(FD); 3133} 3134 3135Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3136 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3137} 3138 3139Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3140 bool IsInstantiation) { 3141 Decl *dcl = D.getAs<Decl>(); 3142 Stmt *Body = BodyArg.takeAs<Stmt>(); 3143 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3144 FD->setBody(Body); 3145 3146 if (!FD->isInvalidDecl()) 3147 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3148 3149 // C++ [basic.def.odr]p2: 3150 // [...] A virtual member function is used if it is not pure. [...] 3151 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3152 if (Method->isVirtual() && !Method->isPure()) 3153 MarkDeclarationReferenced(Method->getLocation(), Method); 3154 3155 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3156 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3157 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3158 MD->setBody(Body); 3159 3160 if (!MD->isInvalidDecl()) 3161 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3162 } else { 3163 Body->Destroy(Context); 3164 return DeclPtrTy(); 3165 } 3166 if (!IsInstantiation) 3167 PopDeclContext(); 3168 3169 // Verify and clean out per-function state. 3170 3171 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3172 3173 // Check goto/label use. 3174 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3175 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3176 LabelStmt *L = I->second; 3177 3178 // Verify that we have no forward references left. If so, there was a goto 3179 // or address of a label taken, but no definition of it. Label fwd 3180 // definitions are indicated with a null substmt. 3181 if (L->getSubStmt() != 0) 3182 continue; 3183 3184 // Emit error. 3185 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3186 3187 // At this point, we have gotos that use the bogus label. Stitch it into 3188 // the function body so that they aren't leaked and that the AST is well 3189 // formed. 3190 if (Body == 0) { 3191 // The whole function wasn't parsed correctly, just delete this. 3192 L->Destroy(Context); 3193 continue; 3194 } 3195 3196 // Otherwise, the body is valid: we want to stitch the label decl into the 3197 // function somewhere so that it is properly owned and so that the goto 3198 // has a valid target. Do this by creating a new compound stmt with the 3199 // label in it. 3200 3201 // Give the label a sub-statement. 3202 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3203 3204 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3205 cast<CXXTryStmt>(Body)->getTryBlock() : 3206 cast<CompoundStmt>(Body); 3207 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3208 Elements.push_back(L); 3209 Compound->setStmts(Context, &Elements[0], Elements.size()); 3210 } 3211 FunctionLabelMap.clear(); 3212 3213 if (!Body) return D; 3214 3215 // Verify that that gotos and switch cases don't jump into scopes illegally. 3216 if (CurFunctionNeedsScopeChecking) 3217 DiagnoseInvalidJumps(Body); 3218 3219 // C++ constructors that have function-try-blocks can't have return statements 3220 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3221 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3222 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3223 3224 return D; 3225} 3226 3227/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3228/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3229NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3230 IdentifierInfo &II, Scope *S) { 3231 // Before we produce a declaration for an implicitly defined 3232 // function, see whether there was a locally-scoped declaration of 3233 // this name as a function or variable. If so, use that 3234 // (non-visible) declaration, and complain about it. 3235 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3236 = LocallyScopedExternalDecls.find(&II); 3237 if (Pos != LocallyScopedExternalDecls.end()) { 3238 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3239 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3240 return Pos->second; 3241 } 3242 3243 // Extension in C99. Legal in C90, but warn about it. 3244 if (getLangOptions().C99) 3245 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3246 else 3247 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3248 3249 // FIXME: handle stuff like: 3250 // void foo() { extern float X(); } 3251 // void bar() { X(); } <-- implicit decl for X in another scope. 3252 3253 // Set a Declarator for the implicit definition: int foo(); 3254 const char *Dummy; 3255 DeclSpec DS; 3256 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3257 Error = Error; // Silence warning. 3258 assert(!Error && "Error setting up implicit decl!"); 3259 Declarator D(DS, Declarator::BlockContext); 3260 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3261 0, 0, false, SourceLocation(), 3262 false, 0,0,0, Loc, D), 3263 SourceLocation()); 3264 D.SetIdentifier(&II, Loc); 3265 3266 // Insert this function into translation-unit scope. 3267 3268 DeclContext *PrevDC = CurContext; 3269 CurContext = Context.getTranslationUnitDecl(); 3270 3271 FunctionDecl *FD = 3272 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3273 FD->setImplicit(); 3274 3275 CurContext = PrevDC; 3276 3277 AddKnownFunctionAttributes(FD); 3278 3279 return FD; 3280} 3281 3282/// \brief Adds any function attributes that we know a priori based on 3283/// the declaration of this function. 3284/// 3285/// These attributes can apply both to implicitly-declared builtins 3286/// (like __builtin___printf_chk) or to library-declared functions 3287/// like NSLog or printf. 3288void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3289 if (FD->isInvalidDecl()) 3290 return; 3291 3292 // If this is a built-in function, map its builtin attributes to 3293 // actual attributes. 3294 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3295 // Handle printf-formatting attributes. 3296 unsigned FormatIdx; 3297 bool HasVAListArg; 3298 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3299 if (!FD->getAttr<FormatAttr>(Context)) 3300 FD->addAttr(Context, 3301 ::new (Context) FormatAttr("printf", FormatIdx + 1, 3302 HasVAListArg ? 0 : FormatIdx + 2)); 3303 } 3304 3305 // Mark const if we don't care about errno and that is the only 3306 // thing preventing the function from being const. This allows 3307 // IRgen to use LLVM intrinsics for such functions. 3308 if (!getLangOptions().MathErrno && 3309 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3310 if (!FD->getAttr<ConstAttr>(Context)) 3311 FD->addAttr(Context, ::new (Context) ConstAttr()); 3312 } 3313 } 3314 3315 IdentifierInfo *Name = FD->getIdentifier(); 3316 if (!Name) 3317 return; 3318 if ((!getLangOptions().CPlusPlus && 3319 FD->getDeclContext()->isTranslationUnit()) || 3320 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3321 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3322 LinkageSpecDecl::lang_c)) { 3323 // Okay: this could be a libc/libm/Objective-C function we know 3324 // about. 3325 } else 3326 return; 3327 3328 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3329 if (const FormatAttr *Format = FD->getAttr<FormatAttr>(Context)) { 3330 // FIXME: We known better than our headers. 3331 const_cast<FormatAttr *>(Format)->setType("printf"); 3332 } else 3333 FD->addAttr(Context, 3334 ::new (Context) FormatAttr("printf", 1, 3335 Name->isStr("NSLogv") ? 0 : 2)); 3336 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3337 if (!FD->getAttr<FormatAttr>(Context)) 3338 FD->addAttr(Context, 3339 ::new (Context) FormatAttr("printf", 2, 3340 Name->isStr("vasprintf") ? 0 : 3)); 3341 } 3342} 3343 3344TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3345 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3346 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3347 3348 // Scope manipulation handled by caller. 3349 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3350 D.getIdentifierLoc(), 3351 D.getIdentifier(), 3352 T); 3353 3354 if (TagType *TT = dyn_cast<TagType>(T)) { 3355 TagDecl *TD = TT->getDecl(); 3356 3357 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3358 // keep track of the TypedefDecl. 3359 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3360 TD->setTypedefForAnonDecl(NewTD); 3361 } 3362 3363 if (D.isInvalidType()) 3364 NewTD->setInvalidDecl(); 3365 return NewTD; 3366} 3367 3368 3369/// \brief Determine whether a tag with a given kind is acceptable 3370/// as a redeclaration of the given tag declaration. 3371/// 3372/// \returns true if the new tag kind is acceptable, false otherwise. 3373bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3374 TagDecl::TagKind NewTag, 3375 SourceLocation NewTagLoc, 3376 const IdentifierInfo &Name) { 3377 // C++ [dcl.type.elab]p3: 3378 // The class-key or enum keyword present in the 3379 // elaborated-type-specifier shall agree in kind with the 3380 // declaration to which the name in theelaborated-type-specifier 3381 // refers. This rule also applies to the form of 3382 // elaborated-type-specifier that declares a class-name or 3383 // friend class since it can be construed as referring to the 3384 // definition of the class. Thus, in any 3385 // elaborated-type-specifier, the enum keyword shall be used to 3386 // refer to an enumeration (7.2), the union class-keyshall be 3387 // used to refer to a union (clause 9), and either the class or 3388 // struct class-key shall be used to refer to a class (clause 9) 3389 // declared using the class or struct class-key. 3390 TagDecl::TagKind OldTag = Previous->getTagKind(); 3391 if (OldTag == NewTag) 3392 return true; 3393 3394 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3395 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3396 // Warn about the struct/class tag mismatch. 3397 bool isTemplate = false; 3398 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3399 isTemplate = Record->getDescribedClassTemplate(); 3400 3401 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3402 << (NewTag == TagDecl::TK_class) 3403 << isTemplate << &Name 3404 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3405 OldTag == TagDecl::TK_class? "class" : "struct"); 3406 Diag(Previous->getLocation(), diag::note_previous_use); 3407 return true; 3408 } 3409 return false; 3410} 3411 3412/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3413/// former case, Name will be non-null. In the later case, Name will be null. 3414/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3415/// reference/declaration/definition of a tag. 3416Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3417 SourceLocation KWLoc, const CXXScopeSpec &SS, 3418 IdentifierInfo *Name, SourceLocation NameLoc, 3419 AttributeList *Attr, AccessSpecifier AS, 3420 bool &OwnedDecl) { 3421 // If this is not a definition, it must have a name. 3422 assert((Name != 0 || TK == TK_Definition) && 3423 "Nameless record must be a definition!"); 3424 3425 OwnedDecl = false; 3426 TagDecl::TagKind Kind; 3427 switch (TagSpec) { 3428 default: assert(0 && "Unknown tag type!"); 3429 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3430 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3431 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3432 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3433 } 3434 3435 DeclContext *SearchDC = CurContext; 3436 DeclContext *DC = CurContext; 3437 NamedDecl *PrevDecl = 0; 3438 3439 bool Invalid = false; 3440 3441 if (Name && SS.isNotEmpty()) { 3442 // We have a nested-name tag ('struct foo::bar'). 3443 3444 // Check for invalid 'foo::'. 3445 if (SS.isInvalid()) { 3446 Name = 0; 3447 goto CreateNewDecl; 3448 } 3449 3450 if (RequireCompleteDeclContext(SS)) 3451 return DeclPtrTy::make((Decl *)0); 3452 3453 DC = computeDeclContext(SS); 3454 SearchDC = DC; 3455 // Look-up name inside 'foo::'. 3456 PrevDecl 3457 = dyn_cast_or_null<TagDecl>( 3458 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3459 3460 // A tag 'foo::bar' must already exist. 3461 if (PrevDecl == 0) { 3462 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3463 Name = 0; 3464 Invalid = true; 3465 goto CreateNewDecl; 3466 } 3467 } else if (Name) { 3468 // If this is a named struct, check to see if there was a previous forward 3469 // declaration or definition. 3470 // FIXME: We're looking into outer scopes here, even when we 3471 // shouldn't be. Doing so can result in ambiguities that we 3472 // shouldn't be diagnosing. 3473 LookupResult R = LookupName(S, Name, LookupTagName, 3474 /*RedeclarationOnly=*/(TK != TK_Reference)); 3475 if (R.isAmbiguous()) { 3476 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3477 // FIXME: This is not best way to recover from case like: 3478 // 3479 // struct S s; 3480 // 3481 // causes needless "incomplete type" error later. 3482 Name = 0; 3483 PrevDecl = 0; 3484 Invalid = true; 3485 } 3486 else 3487 PrevDecl = R; 3488 3489 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3490 // FIXME: This makes sure that we ignore the contexts associated 3491 // with C structs, unions, and enums when looking for a matching 3492 // tag declaration or definition. See the similar lookup tweak 3493 // in Sema::LookupName; is there a better way to deal with this? 3494 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3495 SearchDC = SearchDC->getParent(); 3496 } 3497 } 3498 3499 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3500 // Maybe we will complain about the shadowed template parameter. 3501 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3502 // Just pretend that we didn't see the previous declaration. 3503 PrevDecl = 0; 3504 } 3505 3506 if (PrevDecl) { 3507 // Check whether the previous declaration is usable. 3508 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3509 3510 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3511 // If this is a use of a previous tag, or if the tag is already declared 3512 // in the same scope (so that the definition/declaration completes or 3513 // rementions the tag), reuse the decl. 3514 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3515 // Make sure that this wasn't declared as an enum and now used as a 3516 // struct or something similar. 3517 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3518 bool SafeToContinue 3519 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3520 Kind != TagDecl::TK_enum); 3521 if (SafeToContinue) 3522 Diag(KWLoc, diag::err_use_with_wrong_tag) 3523 << Name 3524 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3525 PrevTagDecl->getKindName()); 3526 else 3527 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3528 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3529 3530 if (SafeToContinue) 3531 Kind = PrevTagDecl->getTagKind(); 3532 else { 3533 // Recover by making this an anonymous redefinition. 3534 Name = 0; 3535 PrevDecl = 0; 3536 Invalid = true; 3537 } 3538 } 3539 3540 if (!Invalid) { 3541 // If this is a use, just return the declaration we found. 3542 3543 // FIXME: In the future, return a variant or some other clue 3544 // for the consumer of this Decl to know it doesn't own it. 3545 // For our current ASTs this shouldn't be a problem, but will 3546 // need to be changed with DeclGroups. 3547 if (TK == TK_Reference) 3548 return DeclPtrTy::make(PrevDecl); 3549 3550 // Diagnose attempts to redefine a tag. 3551 if (TK == TK_Definition) { 3552 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3553 Diag(NameLoc, diag::err_redefinition) << Name; 3554 Diag(Def->getLocation(), diag::note_previous_definition); 3555 // If this is a redefinition, recover by making this 3556 // struct be anonymous, which will make any later 3557 // references get the previous definition. 3558 Name = 0; 3559 PrevDecl = 0; 3560 Invalid = true; 3561 } else { 3562 // If the type is currently being defined, complain 3563 // about a nested redefinition. 3564 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3565 if (Tag->isBeingDefined()) { 3566 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3567 Diag(PrevTagDecl->getLocation(), 3568 diag::note_previous_definition); 3569 Name = 0; 3570 PrevDecl = 0; 3571 Invalid = true; 3572 } 3573 } 3574 3575 // Okay, this is definition of a previously declared or referenced 3576 // tag PrevDecl. We're going to create a new Decl for it. 3577 } 3578 } 3579 // If we get here we have (another) forward declaration or we 3580 // have a definition. Just create a new decl. 3581 } else { 3582 // If we get here, this is a definition of a new tag type in a nested 3583 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3584 // new decl/type. We set PrevDecl to NULL so that the entities 3585 // have distinct types. 3586 PrevDecl = 0; 3587 } 3588 // If we get here, we're going to create a new Decl. If PrevDecl 3589 // is non-NULL, it's a definition of the tag declared by 3590 // PrevDecl. If it's NULL, we have a new definition. 3591 } else { 3592 // PrevDecl is a namespace, template, or anything else 3593 // that lives in the IDNS_Tag identifier namespace. 3594 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3595 // The tag name clashes with a namespace name, issue an error and 3596 // recover by making this tag be anonymous. 3597 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3598 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3599 Name = 0; 3600 PrevDecl = 0; 3601 Invalid = true; 3602 } else { 3603 // The existing declaration isn't relevant to us; we're in a 3604 // new scope, so clear out the previous declaration. 3605 PrevDecl = 0; 3606 } 3607 } 3608 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3609 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3610 // C++ [basic.scope.pdecl]p5: 3611 // -- for an elaborated-type-specifier of the form 3612 // 3613 // class-key identifier 3614 // 3615 // if the elaborated-type-specifier is used in the 3616 // decl-specifier-seq or parameter-declaration-clause of a 3617 // function defined in namespace scope, the identifier is 3618 // declared as a class-name in the namespace that contains 3619 // the declaration; otherwise, except as a friend 3620 // declaration, the identifier is declared in the smallest 3621 // non-class, non-function-prototype scope that contains the 3622 // declaration. 3623 // 3624 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3625 // C structs and unions. 3626 // 3627 // GNU C also supports this behavior as part of its incomplete 3628 // enum types extension, while GNU C++ does not. 3629 // 3630 // Find the context where we'll be declaring the tag. 3631 // FIXME: We would like to maintain the current DeclContext as the 3632 // lexical context, 3633 while (SearchDC->isRecord()) 3634 SearchDC = SearchDC->getParent(); 3635 3636 // Find the scope where we'll be declaring the tag. 3637 while (S->isClassScope() || 3638 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3639 ((S->getFlags() & Scope::DeclScope) == 0) || 3640 (S->getEntity() && 3641 ((DeclContext *)S->getEntity())->isTransparentContext())) 3642 S = S->getParent(); 3643 } 3644 3645CreateNewDecl: 3646 3647 // If there is an identifier, use the location of the identifier as the 3648 // location of the decl, otherwise use the location of the struct/union 3649 // keyword. 3650 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3651 3652 // Otherwise, create a new declaration. If there is a previous 3653 // declaration of the same entity, the two will be linked via 3654 // PrevDecl. 3655 TagDecl *New; 3656 3657 if (Kind == TagDecl::TK_enum) { 3658 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3659 // enum X { A, B, C } D; D should chain to X. 3660 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3661 cast_or_null<EnumDecl>(PrevDecl)); 3662 // If this is an undefined enum, warn. 3663 if (TK != TK_Definition && !Invalid) { 3664 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3665 : diag::ext_forward_ref_enum; 3666 Diag(Loc, DK); 3667 } 3668 } else { 3669 // struct/union/class 3670 3671 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3672 // struct X { int A; } D; D should chain to X. 3673 if (getLangOptions().CPlusPlus) 3674 // FIXME: Look for a way to use RecordDecl for simple structs. 3675 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3676 cast_or_null<CXXRecordDecl>(PrevDecl)); 3677 else 3678 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3679 cast_or_null<RecordDecl>(PrevDecl)); 3680 } 3681 3682 if (Kind != TagDecl::TK_enum) { 3683 // Handle #pragma pack: if the #pragma pack stack has non-default 3684 // alignment, make up a packed attribute for this decl. These 3685 // attributes are checked when the ASTContext lays out the 3686 // structure. 3687 // 3688 // It is important for implementing the correct semantics that this 3689 // happen here (in act on tag decl). The #pragma pack stack is 3690 // maintained as a result of parser callbacks which can occur at 3691 // many points during the parsing of a struct declaration (because 3692 // the #pragma tokens are effectively skipped over during the 3693 // parsing of the struct). 3694 if (unsigned Alignment = getPragmaPackAlignment()) 3695 New->addAttr(Context, ::new (Context) PackedAttr(Alignment * 8)); 3696 } 3697 3698 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3699 // C++ [dcl.typedef]p3: 3700 // [...] Similarly, in a given scope, a class or enumeration 3701 // shall not be declared with the same name as a typedef-name 3702 // that is declared in that scope and refers to a type other 3703 // than the class or enumeration itself. 3704 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3705 TypedefDecl *PrevTypedef = 0; 3706 if (Lookup.getKind() == LookupResult::Found) 3707 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3708 3709 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3710 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3711 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3712 Diag(Loc, diag::err_tag_definition_of_typedef) 3713 << Context.getTypeDeclType(New) 3714 << PrevTypedef->getUnderlyingType(); 3715 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3716 Invalid = true; 3717 } 3718 } 3719 3720 if (Invalid) 3721 New->setInvalidDecl(); 3722 3723 if (Attr) 3724 ProcessDeclAttributeList(S, New, Attr); 3725 3726 // If we're declaring or defining a tag in function prototype scope 3727 // in C, note that this type can only be used within the function. 3728 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3729 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3730 3731 // Set the lexical context. If the tag has a C++ scope specifier, the 3732 // lexical context will be different from the semantic context. 3733 New->setLexicalDeclContext(CurContext); 3734 3735 // Set the access specifier. 3736 if (!Invalid) 3737 SetMemberAccessSpecifier(New, PrevDecl, AS); 3738 3739 if (TK == TK_Definition) 3740 New->startDefinition(); 3741 3742 // If this has an identifier, add it to the scope stack. 3743 if (Name) { 3744 S = getNonFieldDeclScope(S); 3745 PushOnScopeChains(New, S); 3746 } else { 3747 CurContext->addDecl(Context, New); 3748 } 3749 3750 OwnedDecl = true; 3751 return DeclPtrTy::make(New); 3752} 3753 3754void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3755 AdjustDeclIfTemplate(TagD); 3756 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3757 3758 // Enter the tag context. 3759 PushDeclContext(S, Tag); 3760 3761 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3762 FieldCollector->StartClass(); 3763 3764 if (Record->getIdentifier()) { 3765 // C++ [class]p2: 3766 // [...] The class-name is also inserted into the scope of the 3767 // class itself; this is known as the injected-class-name. For 3768 // purposes of access checking, the injected-class-name is treated 3769 // as if it were a public member name. 3770 CXXRecordDecl *InjectedClassName 3771 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3772 CurContext, Record->getLocation(), 3773 Record->getIdentifier(), Record); 3774 InjectedClassName->setImplicit(); 3775 InjectedClassName->setAccess(AS_public); 3776 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3777 InjectedClassName->setDescribedClassTemplate(Template); 3778 PushOnScopeChains(InjectedClassName, S); 3779 assert(InjectedClassName->isInjectedClassName() && 3780 "Broken injected-class-name"); 3781 } 3782 } 3783} 3784 3785void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3786 AdjustDeclIfTemplate(TagD); 3787 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3788 3789 if (isa<CXXRecordDecl>(Tag)) 3790 FieldCollector->FinishClass(); 3791 3792 // Exit this scope of this tag's definition. 3793 PopDeclContext(); 3794 3795 // Notify the consumer that we've defined a tag. 3796 Consumer.HandleTagDeclDefinition(Tag); 3797} 3798 3799// Note that FieldName may be null for anonymous bitfields. 3800bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3801 QualType FieldTy, const Expr *BitWidth) { 3802 3803 // C99 6.7.2.1p4 - verify the field type. 3804 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3805 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3806 // Handle incomplete types with specific error. 3807 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3808 return true; 3809 if (FieldName) 3810 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3811 << FieldName << FieldTy << BitWidth->getSourceRange(); 3812 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3813 << FieldTy << BitWidth->getSourceRange(); 3814 } 3815 3816 // If the bit-width is type- or value-dependent, don't try to check 3817 // it now. 3818 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3819 return false; 3820 3821 llvm::APSInt Value; 3822 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3823 return true; 3824 3825 // Zero-width bitfield is ok for anonymous field. 3826 if (Value == 0 && FieldName) 3827 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3828 3829 if (Value.isSigned() && Value.isNegative()) { 3830 if (FieldName) 3831 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3832 << FieldName << Value.toString(10); 3833 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3834 << Value.toString(10); 3835 } 3836 3837 if (!FieldTy->isDependentType()) { 3838 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3839 if (Value.getZExtValue() > TypeSize) { 3840 if (FieldName) 3841 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3842 << FieldName << (unsigned)TypeSize; 3843 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3844 << (unsigned)TypeSize; 3845 } 3846 } 3847 3848 return false; 3849} 3850 3851/// ActOnField - Each field of a struct/union/class is passed into this in order 3852/// to create a FieldDecl object for it. 3853Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3854 SourceLocation DeclStart, 3855 Declarator &D, ExprTy *BitfieldWidth) { 3856 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3857 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3858 AS_public); 3859 return DeclPtrTy::make(Res); 3860} 3861 3862/// HandleField - Analyze a field of a C struct or a C++ data member. 3863/// 3864FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3865 SourceLocation DeclStart, 3866 Declarator &D, Expr *BitWidth, 3867 AccessSpecifier AS) { 3868 IdentifierInfo *II = D.getIdentifier(); 3869 SourceLocation Loc = DeclStart; 3870 if (II) Loc = D.getIdentifierLoc(); 3871 3872 QualType T = GetTypeForDeclarator(D, S); 3873 if (getLangOptions().CPlusPlus) 3874 CheckExtraCXXDefaultArguments(D); 3875 3876 DiagnoseFunctionSpecifiers(D); 3877 3878 if (D.getDeclSpec().isThreadSpecified()) 3879 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3880 3881 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3882 3883 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3884 // Maybe we will complain about the shadowed template parameter. 3885 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3886 // Just pretend that we didn't see the previous declaration. 3887 PrevDecl = 0; 3888 } 3889 3890 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3891 PrevDecl = 0; 3892 3893 FieldDecl *NewFD 3894 = CheckFieldDecl(II, T, Record, Loc, 3895 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3896 BitWidth, AS, PrevDecl, &D); 3897 if (NewFD->isInvalidDecl() && PrevDecl) { 3898 // Don't introduce NewFD into scope; there's already something 3899 // with the same name in the same scope. 3900 } else if (II) { 3901 PushOnScopeChains(NewFD, S); 3902 } else 3903 Record->addDecl(Context, NewFD); 3904 3905 return NewFD; 3906} 3907 3908/// \brief Build a new FieldDecl and check its well-formedness. 3909/// 3910/// This routine builds a new FieldDecl given the fields name, type, 3911/// record, etc. \p PrevDecl should refer to any previous declaration 3912/// with the same name and in the same scope as the field to be 3913/// created. 3914/// 3915/// \returns a new FieldDecl. 3916/// 3917/// \todo The Declarator argument is a hack. It will be removed once 3918FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3919 RecordDecl *Record, SourceLocation Loc, 3920 bool Mutable, Expr *BitWidth, 3921 AccessSpecifier AS, NamedDecl *PrevDecl, 3922 Declarator *D) { 3923 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3924 bool InvalidDecl = false; 3925 if (D) InvalidDecl = D->isInvalidType(); 3926 3927 // If we receive a broken type, recover by assuming 'int' and 3928 // marking this declaration as invalid. 3929 if (T.isNull()) { 3930 InvalidDecl = true; 3931 T = Context.IntTy; 3932 } 3933 3934 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3935 // than a variably modified type. 3936 if (T->isVariablyModifiedType()) { 3937 bool SizeIsNegative; 3938 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3939 SizeIsNegative); 3940 if (!FixedTy.isNull()) { 3941 Diag(Loc, diag::warn_illegal_constant_array_size); 3942 T = FixedTy; 3943 } else { 3944 if (SizeIsNegative) 3945 Diag(Loc, diag::err_typecheck_negative_array_size); 3946 else 3947 Diag(Loc, diag::err_typecheck_field_variable_size); 3948 T = Context.IntTy; 3949 InvalidDecl = true; 3950 } 3951 } 3952 3953 // Fields can not have abstract class types 3954 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3955 AbstractFieldType)) 3956 InvalidDecl = true; 3957 3958 // If this is declared as a bit-field, check the bit-field. 3959 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3960 InvalidDecl = true; 3961 DeleteExpr(BitWidth); 3962 BitWidth = 0; 3963 } 3964 3965 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3966 Mutable); 3967 if (InvalidDecl) 3968 NewFD->setInvalidDecl(); 3969 3970 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3971 Diag(Loc, diag::err_duplicate_member) << II; 3972 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3973 NewFD->setInvalidDecl(); 3974 } 3975 3976 if (getLangOptions().CPlusPlus && !T->isPODType()) 3977 cast<CXXRecordDecl>(Record)->setPOD(false); 3978 3979 // FIXME: We need to pass in the attributes given an AST 3980 // representation, not a parser representation. 3981 if (D) 3982 // FIXME: What to pass instead of TUScope? 3983 ProcessDeclAttributes(TUScope, NewFD, *D); 3984 3985 if (T.isObjCGCWeak()) 3986 Diag(Loc, diag::warn_attribute_weak_on_field); 3987 3988 NewFD->setAccess(AS); 3989 3990 // C++ [dcl.init.aggr]p1: 3991 // An aggregate is an array or a class (clause 9) with [...] no 3992 // private or protected non-static data members (clause 11). 3993 // A POD must be an aggregate. 3994 if (getLangOptions().CPlusPlus && 3995 (AS == AS_private || AS == AS_protected)) { 3996 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3997 CXXRecord->setAggregate(false); 3998 CXXRecord->setPOD(false); 3999 } 4000 4001 return NewFD; 4002} 4003 4004/// TranslateIvarVisibility - Translate visibility from a token ID to an 4005/// AST enum value. 4006static ObjCIvarDecl::AccessControl 4007TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4008 switch (ivarVisibility) { 4009 default: assert(0 && "Unknown visitibility kind"); 4010 case tok::objc_private: return ObjCIvarDecl::Private; 4011 case tok::objc_public: return ObjCIvarDecl::Public; 4012 case tok::objc_protected: return ObjCIvarDecl::Protected; 4013 case tok::objc_package: return ObjCIvarDecl::Package; 4014 } 4015} 4016 4017/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4018/// in order to create an IvarDecl object for it. 4019Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4020 SourceLocation DeclStart, 4021 DeclPtrTy IntfDecl, 4022 Declarator &D, ExprTy *BitfieldWidth, 4023 tok::ObjCKeywordKind Visibility) { 4024 4025 IdentifierInfo *II = D.getIdentifier(); 4026 Expr *BitWidth = (Expr*)BitfieldWidth; 4027 SourceLocation Loc = DeclStart; 4028 if (II) Loc = D.getIdentifierLoc(); 4029 4030 // FIXME: Unnamed fields can be handled in various different ways, for 4031 // example, unnamed unions inject all members into the struct namespace! 4032 4033 QualType T = GetTypeForDeclarator(D, S); 4034 4035 if (BitWidth) { 4036 // 6.7.2.1p3, 6.7.2.1p4 4037 if (VerifyBitField(Loc, II, T, BitWidth)) { 4038 D.setInvalidType(); 4039 DeleteExpr(BitWidth); 4040 BitWidth = 0; 4041 } 4042 } else { 4043 // Not a bitfield. 4044 4045 // validate II. 4046 4047 } 4048 4049 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4050 // than a variably modified type. 4051 if (T->isVariablyModifiedType()) { 4052 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4053 D.setInvalidType(); 4054 } 4055 4056 // Get the visibility (access control) for this ivar. 4057 ObjCIvarDecl::AccessControl ac = 4058 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4059 : ObjCIvarDecl::None; 4060 // Must set ivar's DeclContext to its enclosing interface. 4061 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4062 DeclContext *EnclosingContext; 4063 if (ObjCImplementationDecl *IMPDecl = 4064 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4065 // Case of ivar declared in an implementation. Context is that of its class. 4066 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4067 assert(IDecl && "No class- ActOnIvar"); 4068 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4069 } 4070 else 4071 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4072 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4073 4074 // Construct the decl. 4075 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4076 EnclosingContext, Loc, II, T,ac, 4077 (Expr *)BitfieldWidth); 4078 4079 if (II) { 4080 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4081 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4082 && !isa<TagDecl>(PrevDecl)) { 4083 Diag(Loc, diag::err_duplicate_member) << II; 4084 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4085 NewID->setInvalidDecl(); 4086 } 4087 } 4088 4089 // Process attributes attached to the ivar. 4090 ProcessDeclAttributes(S, NewID, D); 4091 4092 if (D.isInvalidType()) 4093 NewID->setInvalidDecl(); 4094 4095 if (II) { 4096 // FIXME: When interfaces are DeclContexts, we'll need to add 4097 // these to the interface. 4098 S->AddDecl(DeclPtrTy::make(NewID)); 4099 IdResolver.AddDecl(NewID); 4100 } 4101 4102 return DeclPtrTy::make(NewID); 4103} 4104 4105void Sema::ActOnFields(Scope* S, 4106 SourceLocation RecLoc, DeclPtrTy RecDecl, 4107 DeclPtrTy *Fields, unsigned NumFields, 4108 SourceLocation LBrac, SourceLocation RBrac, 4109 AttributeList *Attr) { 4110 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4111 assert(EnclosingDecl && "missing record or interface decl"); 4112 4113 // If the decl this is being inserted into is invalid, then it may be a 4114 // redeclaration or some other bogus case. Don't try to add fields to it. 4115 if (EnclosingDecl->isInvalidDecl()) { 4116 // FIXME: Deallocate fields? 4117 return; 4118 } 4119 4120 4121 // Verify that all the fields are okay. 4122 unsigned NumNamedMembers = 0; 4123 llvm::SmallVector<FieldDecl*, 32> RecFields; 4124 4125 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4126 for (unsigned i = 0; i != NumFields; ++i) { 4127 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4128 4129 // Get the type for the field. 4130 Type *FDTy = FD->getType().getTypePtr(); 4131 4132 if (!FD->isAnonymousStructOrUnion()) { 4133 // Remember all fields written by the user. 4134 RecFields.push_back(FD); 4135 } 4136 4137 // If the field is already invalid for some reason, don't emit more 4138 // diagnostics about it. 4139 if (FD->isInvalidDecl()) 4140 continue; 4141 4142 // C99 6.7.2.1p2: 4143 // A structure or union shall not contain a member with 4144 // incomplete or function type (hence, a structure shall not 4145 // contain an instance of itself, but may contain a pointer to 4146 // an instance of itself), except that the last member of a 4147 // structure with more than one named member may have incomplete 4148 // array type; such a structure (and any union containing, 4149 // possibly recursively, a member that is such a structure) 4150 // shall not be a member of a structure or an element of an 4151 // array. 4152 if (FDTy->isFunctionType()) { 4153 // Field declared as a function. 4154 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4155 << FD->getDeclName(); 4156 FD->setInvalidDecl(); 4157 EnclosingDecl->setInvalidDecl(); 4158 continue; 4159 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4160 Record && Record->isStruct()) { 4161 // Flexible array member. 4162 if (NumNamedMembers < 1) { 4163 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4164 << FD->getDeclName(); 4165 FD->setInvalidDecl(); 4166 EnclosingDecl->setInvalidDecl(); 4167 continue; 4168 } 4169 // Okay, we have a legal flexible array member at the end of the struct. 4170 if (Record) 4171 Record->setHasFlexibleArrayMember(true); 4172 } else if (!FDTy->isDependentType() && 4173 RequireCompleteType(FD->getLocation(), FD->getType(), 4174 diag::err_field_incomplete)) { 4175 // Incomplete type 4176 FD->setInvalidDecl(); 4177 EnclosingDecl->setInvalidDecl(); 4178 continue; 4179 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4180 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4181 // If this is a member of a union, then entire union becomes "flexible". 4182 if (Record && Record->isUnion()) { 4183 Record->setHasFlexibleArrayMember(true); 4184 } else { 4185 // If this is a struct/class and this is not the last element, reject 4186 // it. Note that GCC supports variable sized arrays in the middle of 4187 // structures. 4188 if (i != NumFields-1) 4189 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4190 << FD->getDeclName() << FD->getType(); 4191 else { 4192 // We support flexible arrays at the end of structs in 4193 // other structs as an extension. 4194 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4195 << FD->getDeclName(); 4196 if (Record) 4197 Record->setHasFlexibleArrayMember(true); 4198 } 4199 } 4200 } 4201 } else if (FDTy->isObjCInterfaceType()) { 4202 /// A field cannot be an Objective-c object 4203 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4204 FD->setInvalidDecl(); 4205 EnclosingDecl->setInvalidDecl(); 4206 continue; 4207 } 4208 // Keep track of the number of named members. 4209 if (FD->getIdentifier()) 4210 ++NumNamedMembers; 4211 } 4212 4213 // Okay, we successfully defined 'Record'. 4214 if (Record) { 4215 Record->completeDefinition(Context); 4216 } else { 4217 ObjCIvarDecl **ClsFields = 4218 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4219 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4220 ID->setIVarList(ClsFields, RecFields.size(), Context); 4221 ID->setLocEnd(RBrac); 4222 // Add ivar's to class's DeclContext. 4223 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4224 ClsFields[i]->setLexicalDeclContext(ID); 4225 ID->addDecl(Context, ClsFields[i]); 4226 } 4227 // Must enforce the rule that ivars in the base classes may not be 4228 // duplicates. 4229 if (ID->getSuperClass()) { 4230 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4231 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4232 ObjCIvarDecl* Ivar = (*IVI); 4233 4234 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4235 ObjCIvarDecl* prevIvar = 4236 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4237 if (prevIvar) { 4238 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4239 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4240 } 4241 } 4242 } 4243 } 4244 } else if (ObjCImplementationDecl *IMPDecl = 4245 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4246 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4247 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4248 // Ivar declared in @implementation never belongs to the implementation. 4249 // Only it is in implementation's lexical context. 4250 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4251 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4252 } 4253 } 4254 4255 if (Attr) 4256 ProcessDeclAttributeList(S, Record, Attr); 4257} 4258 4259EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4260 EnumConstantDecl *LastEnumConst, 4261 SourceLocation IdLoc, 4262 IdentifierInfo *Id, 4263 ExprArg val) { 4264 Expr *Val = (Expr *)val.get(); 4265 4266 llvm::APSInt EnumVal(32); 4267 QualType EltTy; 4268 if (Val && !Val->isTypeDependent()) { 4269 // Make sure to promote the operand type to int. 4270 UsualUnaryConversions(Val); 4271 if (Val != val.get()) { 4272 val.release(); 4273 val = Val; 4274 } 4275 4276 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4277 SourceLocation ExpLoc; 4278 if (!Val->isValueDependent() && 4279 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4280 Val = 0; 4281 } else { 4282 EltTy = Val->getType(); 4283 } 4284 } 4285 4286 if (!Val) { 4287 if (LastEnumConst) { 4288 // Assign the last value + 1. 4289 EnumVal = LastEnumConst->getInitVal(); 4290 ++EnumVal; 4291 4292 // Check for overflow on increment. 4293 if (EnumVal < LastEnumConst->getInitVal()) 4294 Diag(IdLoc, diag::warn_enum_value_overflow); 4295 4296 EltTy = LastEnumConst->getType(); 4297 } else { 4298 // First value, set to zero. 4299 EltTy = Context.IntTy; 4300 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4301 } 4302 } 4303 4304 val.release(); 4305 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4306 Val, EnumVal); 4307} 4308 4309 4310Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4311 DeclPtrTy lastEnumConst, 4312 SourceLocation IdLoc, 4313 IdentifierInfo *Id, 4314 SourceLocation EqualLoc, ExprTy *val) { 4315 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4316 EnumConstantDecl *LastEnumConst = 4317 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4318 Expr *Val = static_cast<Expr*>(val); 4319 4320 // The scope passed in may not be a decl scope. Zip up the scope tree until 4321 // we find one that is. 4322 S = getNonFieldDeclScope(S); 4323 4324 // Verify that there isn't already something declared with this name in this 4325 // scope. 4326 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4327 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4328 // Maybe we will complain about the shadowed template parameter. 4329 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4330 // Just pretend that we didn't see the previous declaration. 4331 PrevDecl = 0; 4332 } 4333 4334 if (PrevDecl) { 4335 // When in C++, we may get a TagDecl with the same name; in this case the 4336 // enum constant will 'hide' the tag. 4337 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4338 "Received TagDecl when not in C++!"); 4339 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4340 if (isa<EnumConstantDecl>(PrevDecl)) 4341 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4342 else 4343 Diag(IdLoc, diag::err_redefinition) << Id; 4344 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4345 if (Val) Val->Destroy(Context); 4346 return DeclPtrTy(); 4347 } 4348 } 4349 4350 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4351 IdLoc, Id, Owned(Val)); 4352 4353 // Register this decl in the current scope stack. 4354 if (New) 4355 PushOnScopeChains(New, S); 4356 4357 return DeclPtrTy::make(New); 4358} 4359 4360void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 4361 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 4362 DeclPtrTy *Elements, unsigned NumElements) { 4363 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4364 QualType EnumType = Context.getTypeDeclType(Enum); 4365 4366 // TODO: If the result value doesn't fit in an int, it must be a long or long 4367 // long value. ISO C does not support this, but GCC does as an extension, 4368 // emit a warning. 4369 unsigned IntWidth = Context.Target.getIntWidth(); 4370 4371 // Verify that all the values are okay, compute the size of the values, and 4372 // reverse the list. 4373 unsigned NumNegativeBits = 0; 4374 unsigned NumPositiveBits = 0; 4375 4376 // Keep track of whether all elements have type int. 4377 bool AllElementsInt = true; 4378 4379 for (unsigned i = 0; i != NumElements; ++i) { 4380 EnumConstantDecl *ECD = 4381 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4382 if (!ECD) continue; // Already issued a diagnostic. 4383 4384 // If the enum value doesn't fit in an int, emit an extension warning. 4385 const llvm::APSInt &InitVal = ECD->getInitVal(); 4386 assert(InitVal.getBitWidth() >= IntWidth && 4387 "Should have promoted value to int"); 4388 if (InitVal.getBitWidth() > IntWidth) { 4389 llvm::APSInt V(InitVal); 4390 V.trunc(IntWidth); 4391 V.extend(InitVal.getBitWidth()); 4392 if (V != InitVal) 4393 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4394 << InitVal.toString(10); 4395 } 4396 4397 // Keep track of the size of positive and negative values. 4398 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4399 NumPositiveBits = std::max(NumPositiveBits, 4400 (unsigned)InitVal.getActiveBits()); 4401 else 4402 NumNegativeBits = std::max(NumNegativeBits, 4403 (unsigned)InitVal.getMinSignedBits()); 4404 4405 // Keep track of whether every enum element has type int (very commmon). 4406 if (AllElementsInt) 4407 AllElementsInt = ECD->getType() == Context.IntTy; 4408 } 4409 4410 // Figure out the type that should be used for this enum. 4411 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4412 QualType BestType; 4413 unsigned BestWidth; 4414 4415 if (NumNegativeBits) { 4416 // If there is a negative value, figure out the smallest integer type (of 4417 // int/long/longlong) that fits. 4418 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4419 BestType = Context.IntTy; 4420 BestWidth = IntWidth; 4421 } else { 4422 BestWidth = Context.Target.getLongWidth(); 4423 4424 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4425 BestType = Context.LongTy; 4426 else { 4427 BestWidth = Context.Target.getLongLongWidth(); 4428 4429 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4430 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4431 BestType = Context.LongLongTy; 4432 } 4433 } 4434 } else { 4435 // If there is no negative value, figure out which of uint, ulong, ulonglong 4436 // fits. 4437 if (NumPositiveBits <= IntWidth) { 4438 BestType = Context.UnsignedIntTy; 4439 BestWidth = IntWidth; 4440 } else if (NumPositiveBits <= 4441 (BestWidth = Context.Target.getLongWidth())) { 4442 BestType = Context.UnsignedLongTy; 4443 } else { 4444 BestWidth = Context.Target.getLongLongWidth(); 4445 assert(NumPositiveBits <= BestWidth && 4446 "How could an initializer get larger than ULL?"); 4447 BestType = Context.UnsignedLongLongTy; 4448 } 4449 } 4450 4451 // Loop over all of the enumerator constants, changing their types to match 4452 // the type of the enum if needed. 4453 for (unsigned i = 0; i != NumElements; ++i) { 4454 EnumConstantDecl *ECD = 4455 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4456 if (!ECD) continue; // Already issued a diagnostic. 4457 4458 // Standard C says the enumerators have int type, but we allow, as an 4459 // extension, the enumerators to be larger than int size. If each 4460 // enumerator value fits in an int, type it as an int, otherwise type it the 4461 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4462 // that X has type 'int', not 'unsigned'. 4463 if (ECD->getType() == Context.IntTy) { 4464 // Make sure the init value is signed. 4465 llvm::APSInt IV = ECD->getInitVal(); 4466 IV.setIsSigned(true); 4467 ECD->setInitVal(IV); 4468 4469 if (getLangOptions().CPlusPlus) 4470 // C++ [dcl.enum]p4: Following the closing brace of an 4471 // enum-specifier, each enumerator has the type of its 4472 // enumeration. 4473 ECD->setType(EnumType); 4474 continue; // Already int type. 4475 } 4476 4477 // Determine whether the value fits into an int. 4478 llvm::APSInt InitVal = ECD->getInitVal(); 4479 bool FitsInInt; 4480 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4481 FitsInInt = InitVal.getActiveBits() < IntWidth; 4482 else 4483 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4484 4485 // If it fits into an integer type, force it. Otherwise force it to match 4486 // the enum decl type. 4487 QualType NewTy; 4488 unsigned NewWidth; 4489 bool NewSign; 4490 if (FitsInInt) { 4491 NewTy = Context.IntTy; 4492 NewWidth = IntWidth; 4493 NewSign = true; 4494 } else if (ECD->getType() == BestType) { 4495 // Already the right type! 4496 if (getLangOptions().CPlusPlus) 4497 // C++ [dcl.enum]p4: Following the closing brace of an 4498 // enum-specifier, each enumerator has the type of its 4499 // enumeration. 4500 ECD->setType(EnumType); 4501 continue; 4502 } else { 4503 NewTy = BestType; 4504 NewWidth = BestWidth; 4505 NewSign = BestType->isSignedIntegerType(); 4506 } 4507 4508 // Adjust the APSInt value. 4509 InitVal.extOrTrunc(NewWidth); 4510 InitVal.setIsSigned(NewSign); 4511 ECD->setInitVal(InitVal); 4512 4513 // Adjust the Expr initializer and type. 4514 if (ECD->getInitExpr()) 4515 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4516 /*isLvalue=*/false)); 4517 if (getLangOptions().CPlusPlus) 4518 // C++ [dcl.enum]p4: Following the closing brace of an 4519 // enum-specifier, each enumerator has the type of its 4520 // enumeration. 4521 ECD->setType(EnumType); 4522 else 4523 ECD->setType(NewTy); 4524 } 4525 4526 Enum->completeDefinition(Context, BestType); 4527} 4528 4529Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4530 ExprArg expr) { 4531 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4532 4533 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 4534 Loc, AsmString); 4535 CurContext->addDecl(Context, New); 4536 return DeclPtrTy::make(New); 4537} 4538 4539void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 4540 SourceLocation PragmaLoc, 4541 SourceLocation NameLoc) { 4542 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4543 4544 // FIXME: This implementation is an ugly hack! 4545 if (PrevDecl) { 4546 PrevDecl->addAttr(Context, ::new (Context) WeakAttr()); 4547 return; 4548 } 4549 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4550 return; 4551} 4552 4553void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 4554 IdentifierInfo* AliasName, 4555 SourceLocation PragmaLoc, 4556 SourceLocation NameLoc, 4557 SourceLocation AliasNameLoc) { 4558 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4559 4560 // FIXME: This implementation is an ugly hack! 4561 if (PrevDecl) { 4562 PrevDecl->addAttr(Context, ::new (Context) AliasAttr(AliasName->getName())); 4563 PrevDecl->addAttr(Context, ::new (Context) WeakAttr()); 4564 return; 4565 } 4566 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4567 return; 4568} 4569