SemaDecl.cpp revision 8d2b35630d4afc474b766eeab1f1bef469cf633a
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 isa<FunctionTemplateDecl>(D)) { 325 // We are pushing the name of a function or function template, 326 // which might be an overloaded name. 327 IdentifierResolver::iterator Redecl 328 = std::find_if(IdResolver.begin(D->getDeclName()), 329 IdResolver.end(), 330 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 331 D)); 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 = 0; 659 if (FunctionTemplateDecl *OldFunctionTemplate 660 = dyn_cast<FunctionTemplateDecl>(OldD)) 661 Old = OldFunctionTemplate->getTemplatedDecl(); 662 else 663 Old = dyn_cast<FunctionDecl>(OldD); 664 if (!Old) { 665 Diag(New->getLocation(), diag::err_redefinition_different_kind) 666 << New->getDeclName(); 667 Diag(OldD->getLocation(), diag::note_previous_definition); 668 return true; 669 } 670 671 // Determine whether the previous declaration was a definition, 672 // implicit declaration, or a declaration. 673 diag::kind PrevDiag; 674 if (Old->isThisDeclarationADefinition()) 675 PrevDiag = diag::note_previous_definition; 676 else if (Old->isImplicit()) 677 PrevDiag = diag::note_previous_implicit_declaration; 678 else 679 PrevDiag = diag::note_previous_declaration; 680 681 QualType OldQType = Context.getCanonicalType(Old->getType()); 682 QualType NewQType = Context.getCanonicalType(New->getType()); 683 684 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 685 New->getStorageClass() == FunctionDecl::Static && 686 Old->getStorageClass() != FunctionDecl::Static) { 687 Diag(New->getLocation(), diag::err_static_non_static) 688 << New; 689 Diag(Old->getLocation(), PrevDiag); 690 return true; 691 } 692 693 if (getLangOptions().CPlusPlus) { 694 // (C++98 13.1p2): 695 // Certain function declarations cannot be overloaded: 696 // -- Function declarations that differ only in the return type 697 // cannot be overloaded. 698 QualType OldReturnType 699 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 700 QualType NewReturnType 701 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 702 if (OldReturnType != NewReturnType) { 703 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 704 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 705 return true; 706 } 707 708 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 709 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 710 if (OldMethod && NewMethod && 711 OldMethod->getLexicalDeclContext() == 712 NewMethod->getLexicalDeclContext()) { 713 // -- Member function declarations with the same name and the 714 // same parameter types cannot be overloaded if any of them 715 // is a static member function declaration. 716 if (OldMethod->isStatic() || NewMethod->isStatic()) { 717 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 718 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 719 return true; 720 } 721 722 // C++ [class.mem]p1: 723 // [...] A member shall not be declared twice in the 724 // member-specification, except that a nested class or member 725 // class template can be declared and then later defined. 726 unsigned NewDiag; 727 if (isa<CXXConstructorDecl>(OldMethod)) 728 NewDiag = diag::err_constructor_redeclared; 729 else if (isa<CXXDestructorDecl>(NewMethod)) 730 NewDiag = diag::err_destructor_redeclared; 731 else if (isa<CXXConversionDecl>(NewMethod)) 732 NewDiag = diag::err_conv_function_redeclared; 733 else 734 NewDiag = diag::err_member_redeclared; 735 736 Diag(New->getLocation(), NewDiag); 737 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 738 } 739 740 // (C++98 8.3.5p3): 741 // All declarations for a function shall agree exactly in both the 742 // return type and the parameter-type-list. 743 if (OldQType == NewQType) 744 return MergeCompatibleFunctionDecls(New, Old); 745 746 // Fall through for conflicting redeclarations and redefinitions. 747 } 748 749 // C: Function types need to be compatible, not identical. This handles 750 // duplicate function decls like "void f(int); void f(enum X);" properly. 751 if (!getLangOptions().CPlusPlus && 752 Context.typesAreCompatible(OldQType, NewQType)) { 753 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 754 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 755 const FunctionProtoType *OldProto = 0; 756 if (isa<FunctionNoProtoType>(NewFuncType) && 757 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 758 // The old declaration provided a function prototype, but the 759 // new declaration does not. Merge in the prototype. 760 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 761 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 762 OldProto->arg_type_end()); 763 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 764 ParamTypes.data(), ParamTypes.size(), 765 OldProto->isVariadic(), 766 OldProto->getTypeQuals()); 767 New->setType(NewQType); 768 New->setHasInheritedPrototype(); 769 770 // Synthesize a parameter for each argument type. 771 llvm::SmallVector<ParmVarDecl*, 16> Params; 772 for (FunctionProtoType::arg_type_iterator 773 ParamType = OldProto->arg_type_begin(), 774 ParamEnd = OldProto->arg_type_end(); 775 ParamType != ParamEnd; ++ParamType) { 776 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 777 SourceLocation(), 0, 778 *ParamType, VarDecl::None, 779 0); 780 Param->setImplicit(); 781 Params.push_back(Param); 782 } 783 784 New->setParams(Context, Params.data(), Params.size()); 785 } 786 787 return MergeCompatibleFunctionDecls(New, Old); 788 } 789 790 // GNU C permits a K&R definition to follow a prototype declaration 791 // if the declared types of the parameters in the K&R definition 792 // match the types in the prototype declaration, even when the 793 // promoted types of the parameters from the K&R definition differ 794 // from the types in the prototype. GCC then keeps the types from 795 // the prototype. 796 // 797 // If a variadic prototype is followed by a non-variadic K&R definition, 798 // the K&R definition becomes variadic. This is sort of an edge case, but 799 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 800 // C99 6.9.1p8. 801 if (!getLangOptions().CPlusPlus && 802 Old->hasPrototype() && !New->hasPrototype() && 803 New->getType()->getAsFunctionProtoType() && 804 Old->getNumParams() == New->getNumParams()) { 805 llvm::SmallVector<QualType, 16> ArgTypes; 806 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 807 const FunctionProtoType *OldProto 808 = Old->getType()->getAsFunctionProtoType(); 809 const FunctionProtoType *NewProto 810 = New->getType()->getAsFunctionProtoType(); 811 812 // Determine whether this is the GNU C extension. 813 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 814 NewProto->getResultType()); 815 bool LooseCompatible = !MergedReturn.isNull(); 816 for (unsigned Idx = 0, End = Old->getNumParams(); 817 LooseCompatible && Idx != End; ++Idx) { 818 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 819 ParmVarDecl *NewParm = New->getParamDecl(Idx); 820 if (Context.typesAreCompatible(OldParm->getType(), 821 NewProto->getArgType(Idx))) { 822 ArgTypes.push_back(NewParm->getType()); 823 } else if (Context.typesAreCompatible(OldParm->getType(), 824 NewParm->getType())) { 825 GNUCompatibleParamWarning Warn 826 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 827 Warnings.push_back(Warn); 828 ArgTypes.push_back(NewParm->getType()); 829 } else 830 LooseCompatible = false; 831 } 832 833 if (LooseCompatible) { 834 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 835 Diag(Warnings[Warn].NewParm->getLocation(), 836 diag::ext_param_promoted_not_compatible_with_prototype) 837 << Warnings[Warn].PromotedType 838 << Warnings[Warn].OldParm->getType(); 839 Diag(Warnings[Warn].OldParm->getLocation(), 840 diag::note_previous_declaration); 841 } 842 843 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 844 ArgTypes.size(), 845 OldProto->isVariadic(), 0)); 846 return MergeCompatibleFunctionDecls(New, Old); 847 } 848 849 // Fall through to diagnose conflicting types. 850 } 851 852 // A function that has already been declared has been redeclared or defined 853 // with a different type- show appropriate diagnostic 854 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 855 // The user has declared a builtin function with an incompatible 856 // signature. 857 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 858 // The function the user is redeclaring is a library-defined 859 // function like 'malloc' or 'printf'. Warn about the 860 // redeclaration, then pretend that we don't know about this 861 // library built-in. 862 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 863 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 864 << Old << Old->getType(); 865 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 866 Old->setInvalidDecl(); 867 return false; 868 } 869 870 PrevDiag = diag::note_previous_builtin_declaration; 871 } 872 873 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 874 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 875 return true; 876} 877 878/// \brief Completes the merge of two function declarations that are 879/// known to be compatible. 880/// 881/// This routine handles the merging of attributes and other 882/// properties of function declarations form the old declaration to 883/// the new declaration, once we know that New is in fact a 884/// redeclaration of Old. 885/// 886/// \returns false 887bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 888 // Merge the attributes 889 MergeAttributes(New, Old, Context); 890 891 // Merge the storage class. 892 if (Old->getStorageClass() != FunctionDecl::Extern) 893 New->setStorageClass(Old->getStorageClass()); 894 895 // Merge "inline" 896 if (Old->isInline()) 897 New->setInline(true); 898 899 // If this function declaration by itself qualifies as a C99 inline 900 // definition (C99 6.7.4p6), but the previous definition did not, 901 // then the function is not a C99 inline definition. 902 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 903 New->setC99InlineDefinition(false); 904 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 905 // Mark all preceding definitions as not being C99 inline definitions. 906 for (const FunctionDecl *Prev = Old; Prev; 907 Prev = Prev->getPreviousDeclaration()) 908 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 909 } 910 911 // Merge "pure" flag. 912 if (Old->isPure()) 913 New->setPure(); 914 915 // Merge the "deleted" flag. 916 if (Old->isDeleted()) 917 New->setDeleted(); 918 919 if (getLangOptions().CPlusPlus) 920 return MergeCXXFunctionDecl(New, Old); 921 922 return false; 923} 924 925/// MergeVarDecl - We just parsed a variable 'New' which has the same name 926/// and scope as a previous declaration 'Old'. Figure out how to resolve this 927/// situation, merging decls or emitting diagnostics as appropriate. 928/// 929/// Tentative definition rules (C99 6.9.2p2) are checked by 930/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 931/// definitions here, since the initializer hasn't been attached. 932/// 933void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 934 // If either decl is invalid, make sure the new one is marked invalid and 935 // don't do any other checking. 936 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 937 return New->setInvalidDecl(); 938 939 // Verify the old decl was also a variable. 940 VarDecl *Old = dyn_cast<VarDecl>(OldD); 941 if (!Old) { 942 Diag(New->getLocation(), diag::err_redefinition_different_kind) 943 << New->getDeclName(); 944 Diag(OldD->getLocation(), diag::note_previous_definition); 945 return New->setInvalidDecl(); 946 } 947 948 MergeAttributes(New, Old, Context); 949 950 // Merge the types 951 QualType MergedT; 952 if (getLangOptions().CPlusPlus) { 953 if (Context.hasSameType(New->getType(), Old->getType())) 954 MergedT = New->getType(); 955 } else { 956 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 957 } 958 if (MergedT.isNull()) { 959 Diag(New->getLocation(), diag::err_redefinition_different_type) 960 << New->getDeclName(); 961 Diag(Old->getLocation(), diag::note_previous_definition); 962 return New->setInvalidDecl(); 963 } 964 New->setType(MergedT); 965 966 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 967 if (New->getStorageClass() == VarDecl::Static && 968 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 969 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 970 Diag(Old->getLocation(), diag::note_previous_definition); 971 return New->setInvalidDecl(); 972 } 973 // C99 6.2.2p4: 974 // For an identifier declared with the storage-class specifier 975 // extern in a scope in which a prior declaration of that 976 // identifier is visible,23) if the prior declaration specifies 977 // internal or external linkage, the linkage of the identifier at 978 // the later declaration is the same as the linkage specified at 979 // the prior declaration. If no prior declaration is visible, or 980 // if the prior declaration specifies no linkage, then the 981 // identifier has external linkage. 982 if (New->hasExternalStorage() && Old->hasLinkage()) 983 /* Okay */; 984 else if (New->getStorageClass() != VarDecl::Static && 985 Old->getStorageClass() == VarDecl::Static) { 986 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 987 Diag(Old->getLocation(), diag::note_previous_definition); 988 return New->setInvalidDecl(); 989 } 990 991 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 992 993 // FIXME: The test for external storage here seems wrong? We still 994 // need to check for mismatches. 995 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 996 // Don't complain about out-of-line definitions of static members. 997 !(Old->getLexicalDeclContext()->isRecord() && 998 !New->getLexicalDeclContext()->isRecord())) { 999 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1000 Diag(Old->getLocation(), diag::note_previous_definition); 1001 return New->setInvalidDecl(); 1002 } 1003 1004 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1005 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1006 Diag(Old->getLocation(), diag::note_previous_definition); 1007 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1008 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1009 Diag(Old->getLocation(), diag::note_previous_definition); 1010 } 1011 1012 // Keep a chain of previous declarations. 1013 New->setPreviousDeclaration(Old); 1014} 1015 1016/// CheckParmsForFunctionDef - Check that the parameters of the given 1017/// function are appropriate for the definition of a function. This 1018/// takes care of any checks that cannot be performed on the 1019/// declaration itself, e.g., that the types of each of the function 1020/// parameters are complete. 1021bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1022 bool HasInvalidParm = false; 1023 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1024 ParmVarDecl *Param = FD->getParamDecl(p); 1025 1026 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1027 // function declarator that is part of a function definition of 1028 // that function shall not have incomplete type. 1029 // 1030 // This is also C++ [dcl.fct]p6. 1031 if (!Param->isInvalidDecl() && 1032 RequireCompleteType(Param->getLocation(), Param->getType(), 1033 diag::err_typecheck_decl_incomplete_type)) { 1034 Param->setInvalidDecl(); 1035 HasInvalidParm = true; 1036 } 1037 1038 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1039 // declaration of each parameter shall include an identifier. 1040 if (Param->getIdentifier() == 0 && 1041 !Param->isImplicit() && 1042 !getLangOptions().CPlusPlus) 1043 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1044 } 1045 1046 return HasInvalidParm; 1047} 1048 1049/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1050/// no declarator (e.g. "struct foo;") is parsed. 1051Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1052 // FIXME: Error on auto/register at file scope 1053 // FIXME: Error on inline/virtual/explicit 1054 // FIXME: Error on invalid restrict 1055 // FIXME: Warn on useless __thread 1056 // FIXME: Warn on useless const/volatile 1057 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1058 // FIXME: Warn on useless attributes 1059 TagDecl *Tag = 0; 1060 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1061 DS.getTypeSpecType() == DeclSpec::TST_struct || 1062 DS.getTypeSpecType() == DeclSpec::TST_union || 1063 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1064 if (!DS.getTypeRep()) // We probably had an error 1065 return DeclPtrTy(); 1066 1067 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1068 } 1069 1070 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1071 if (!Record->getDeclName() && Record->isDefinition() && 1072 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1073 if (getLangOptions().CPlusPlus || 1074 Record->getDeclContext()->isRecord()) 1075 return BuildAnonymousStructOrUnion(S, DS, Record); 1076 1077 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1078 << DS.getSourceRange(); 1079 } 1080 1081 // Microsoft allows unnamed struct/union fields. Don't complain 1082 // about them. 1083 // FIXME: Should we support Microsoft's extensions in this area? 1084 if (Record->getDeclName() && getLangOptions().Microsoft) 1085 return DeclPtrTy::make(Tag); 1086 } 1087 1088 if (!DS.isMissingDeclaratorOk() && 1089 DS.getTypeSpecType() != DeclSpec::TST_error) { 1090 // Warn about typedefs of enums without names, since this is an 1091 // extension in both Microsoft an GNU. 1092 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1093 Tag && isa<EnumDecl>(Tag)) { 1094 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1095 << DS.getSourceRange(); 1096 return DeclPtrTy::make(Tag); 1097 } 1098 1099 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1100 << DS.getSourceRange(); 1101 return DeclPtrTy(); 1102 } 1103 1104 return DeclPtrTy::make(Tag); 1105} 1106 1107/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1108/// anonymous struct or union AnonRecord into the owning context Owner 1109/// and scope S. This routine will be invoked just after we realize 1110/// that an unnamed union or struct is actually an anonymous union or 1111/// struct, e.g., 1112/// 1113/// @code 1114/// union { 1115/// int i; 1116/// float f; 1117/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1118/// // f into the surrounding scope.x 1119/// @endcode 1120/// 1121/// This routine is recursive, injecting the names of nested anonymous 1122/// structs/unions into the owning context and scope as well. 1123bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1124 RecordDecl *AnonRecord) { 1125 bool Invalid = false; 1126 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1127 FEnd = AnonRecord->field_end(Context); 1128 F != FEnd; ++F) { 1129 if ((*F)->getDeclName()) { 1130 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1131 LookupOrdinaryName, true); 1132 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1133 // C++ [class.union]p2: 1134 // The names of the members of an anonymous union shall be 1135 // distinct from the names of any other entity in the 1136 // scope in which the anonymous union is declared. 1137 unsigned diagKind 1138 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1139 : diag::err_anonymous_struct_member_redecl; 1140 Diag((*F)->getLocation(), diagKind) 1141 << (*F)->getDeclName(); 1142 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1143 Invalid = true; 1144 } else { 1145 // C++ [class.union]p2: 1146 // For the purpose of name lookup, after the anonymous union 1147 // definition, the members of the anonymous union are 1148 // considered to have been defined in the scope in which the 1149 // anonymous union is declared. 1150 Owner->makeDeclVisibleInContext(Context, *F); 1151 S->AddDecl(DeclPtrTy::make(*F)); 1152 IdResolver.AddDecl(*F); 1153 } 1154 } else if (const RecordType *InnerRecordType 1155 = (*F)->getType()->getAsRecordType()) { 1156 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1157 if (InnerRecord->isAnonymousStructOrUnion()) 1158 Invalid = Invalid || 1159 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1160 } 1161 } 1162 1163 return Invalid; 1164} 1165 1166/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1167/// anonymous structure or union. Anonymous unions are a C++ feature 1168/// (C++ [class.union]) and a GNU C extension; anonymous structures 1169/// are a GNU C and GNU C++ extension. 1170Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1171 RecordDecl *Record) { 1172 DeclContext *Owner = Record->getDeclContext(); 1173 1174 // Diagnose whether this anonymous struct/union is an extension. 1175 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1176 Diag(Record->getLocation(), diag::ext_anonymous_union); 1177 else if (!Record->isUnion()) 1178 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1179 1180 // C and C++ require different kinds of checks for anonymous 1181 // structs/unions. 1182 bool Invalid = false; 1183 if (getLangOptions().CPlusPlus) { 1184 const char* PrevSpec = 0; 1185 // C++ [class.union]p3: 1186 // Anonymous unions declared in a named namespace or in the 1187 // global namespace shall be declared static. 1188 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1189 (isa<TranslationUnitDecl>(Owner) || 1190 (isa<NamespaceDecl>(Owner) && 1191 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1192 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1193 Invalid = true; 1194 1195 // Recover by adding 'static'. 1196 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1197 } 1198 // C++ [class.union]p3: 1199 // A storage class is not allowed in a declaration of an 1200 // anonymous union in a class scope. 1201 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1202 isa<RecordDecl>(Owner)) { 1203 Diag(DS.getStorageClassSpecLoc(), 1204 diag::err_anonymous_union_with_storage_spec); 1205 Invalid = true; 1206 1207 // Recover by removing the storage specifier. 1208 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1209 PrevSpec); 1210 } 1211 1212 // C++ [class.union]p2: 1213 // The member-specification of an anonymous union shall only 1214 // define non-static data members. [Note: nested types and 1215 // functions cannot be declared within an anonymous union. ] 1216 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1217 MemEnd = Record->decls_end(Context); 1218 Mem != MemEnd; ++Mem) { 1219 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1220 // C++ [class.union]p3: 1221 // An anonymous union shall not have private or protected 1222 // members (clause 11). 1223 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1224 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1225 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1226 Invalid = true; 1227 } 1228 } else if ((*Mem)->isImplicit()) { 1229 // Any implicit members are fine. 1230 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1231 // This is a type that showed up in an 1232 // elaborated-type-specifier inside the anonymous struct or 1233 // union, but which actually declares a type outside of the 1234 // anonymous struct or union. It's okay. 1235 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1236 if (!MemRecord->isAnonymousStructOrUnion() && 1237 MemRecord->getDeclName()) { 1238 // This is a nested type declaration. 1239 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1240 << (int)Record->isUnion(); 1241 Invalid = true; 1242 } 1243 } else { 1244 // We have something that isn't a non-static data 1245 // member. Complain about it. 1246 unsigned DK = diag::err_anonymous_record_bad_member; 1247 if (isa<TypeDecl>(*Mem)) 1248 DK = diag::err_anonymous_record_with_type; 1249 else if (isa<FunctionDecl>(*Mem)) 1250 DK = diag::err_anonymous_record_with_function; 1251 else if (isa<VarDecl>(*Mem)) 1252 DK = diag::err_anonymous_record_with_static; 1253 Diag((*Mem)->getLocation(), DK) 1254 << (int)Record->isUnion(); 1255 Invalid = true; 1256 } 1257 } 1258 } 1259 1260 if (!Record->isUnion() && !Owner->isRecord()) { 1261 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1262 << (int)getLangOptions().CPlusPlus; 1263 Invalid = true; 1264 } 1265 1266 // Create a declaration for this anonymous struct/union. 1267 NamedDecl *Anon = 0; 1268 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1269 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1270 /*IdentifierInfo=*/0, 1271 Context.getTypeDeclType(Record), 1272 /*BitWidth=*/0, /*Mutable=*/false); 1273 Anon->setAccess(AS_public); 1274 if (getLangOptions().CPlusPlus) 1275 FieldCollector->Add(cast<FieldDecl>(Anon)); 1276 } else { 1277 VarDecl::StorageClass SC; 1278 switch (DS.getStorageClassSpec()) { 1279 default: assert(0 && "Unknown storage class!"); 1280 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1281 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1282 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1283 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1284 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1285 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1286 case DeclSpec::SCS_mutable: 1287 // mutable can only appear on non-static class members, so it's always 1288 // an error here 1289 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1290 Invalid = true; 1291 SC = VarDecl::None; 1292 break; 1293 } 1294 1295 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1296 /*IdentifierInfo=*/0, 1297 Context.getTypeDeclType(Record), 1298 SC, DS.getSourceRange().getBegin()); 1299 } 1300 Anon->setImplicit(); 1301 1302 // Add the anonymous struct/union object to the current 1303 // context. We'll be referencing this object when we refer to one of 1304 // its members. 1305 Owner->addDecl(Context, Anon); 1306 1307 // Inject the members of the anonymous struct/union into the owning 1308 // context and into the identifier resolver chain for name lookup 1309 // purposes. 1310 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1311 Invalid = true; 1312 1313 // Mark this as an anonymous struct/union type. Note that we do not 1314 // do this until after we have already checked and injected the 1315 // members of this anonymous struct/union type, because otherwise 1316 // the members could be injected twice: once by DeclContext when it 1317 // builds its lookup table, and once by 1318 // InjectAnonymousStructOrUnionMembers. 1319 Record->setAnonymousStructOrUnion(true); 1320 1321 if (Invalid) 1322 Anon->setInvalidDecl(); 1323 1324 return DeclPtrTy::make(Anon); 1325} 1326 1327 1328/// GetNameForDeclarator - Determine the full declaration name for the 1329/// given Declarator. 1330DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1331 switch (D.getKind()) { 1332 case Declarator::DK_Abstract: 1333 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1334 return DeclarationName(); 1335 1336 case Declarator::DK_Normal: 1337 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1338 return DeclarationName(D.getIdentifier()); 1339 1340 case Declarator::DK_Constructor: { 1341 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1342 Ty = Context.getCanonicalType(Ty); 1343 return Context.DeclarationNames.getCXXConstructorName(Ty); 1344 } 1345 1346 case Declarator::DK_Destructor: { 1347 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1348 Ty = Context.getCanonicalType(Ty); 1349 return Context.DeclarationNames.getCXXDestructorName(Ty); 1350 } 1351 1352 case Declarator::DK_Conversion: { 1353 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1354 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1355 Ty = Context.getCanonicalType(Ty); 1356 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1357 } 1358 1359 case Declarator::DK_Operator: 1360 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1361 return Context.DeclarationNames.getCXXOperatorName( 1362 D.getOverloadedOperator()); 1363 } 1364 1365 assert(false && "Unknown name kind"); 1366 return DeclarationName(); 1367} 1368 1369/// isNearlyMatchingFunction - Determine whether the C++ functions 1370/// Declaration and Definition are "nearly" matching. This heuristic 1371/// is used to improve diagnostics in the case where an out-of-line 1372/// function definition doesn't match any declaration within 1373/// the class or namespace. 1374static bool isNearlyMatchingFunction(ASTContext &Context, 1375 FunctionDecl *Declaration, 1376 FunctionDecl *Definition) { 1377 if (Declaration->param_size() != Definition->param_size()) 1378 return false; 1379 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1380 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1381 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1382 1383 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1384 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1385 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1386 return false; 1387 } 1388 1389 return true; 1390} 1391 1392Sema::DeclPtrTy 1393Sema::HandleDeclarator(Scope *S, Declarator &D, 1394 MultiTemplateParamsArg TemplateParamLists, 1395 bool IsFunctionDefinition) { 1396 DeclarationName Name = GetNameForDeclarator(D); 1397 1398 // All of these full declarators require an identifier. If it doesn't have 1399 // one, the ParsedFreeStandingDeclSpec action should be used. 1400 if (!Name) { 1401 if (!D.isInvalidType()) // Reject this if we think it is valid. 1402 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1403 diag::err_declarator_need_ident) 1404 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1405 return DeclPtrTy(); 1406 } 1407 1408 // The scope passed in may not be a decl scope. Zip up the scope tree until 1409 // we find one that is. 1410 while ((S->getFlags() & Scope::DeclScope) == 0 || 1411 (S->getFlags() & Scope::TemplateParamScope) != 0) 1412 S = S->getParent(); 1413 1414 DeclContext *DC; 1415 NamedDecl *PrevDecl; 1416 NamedDecl *New; 1417 1418 QualType R = GetTypeForDeclarator(D, S); 1419 1420 // See if this is a redefinition of a variable in the same scope. 1421 if (D.getCXXScopeSpec().isInvalid()) { 1422 DC = CurContext; 1423 PrevDecl = 0; 1424 D.setInvalidType(); 1425 } else if (!D.getCXXScopeSpec().isSet()) { 1426 LookupNameKind NameKind = LookupOrdinaryName; 1427 1428 // If the declaration we're planning to build will be a function 1429 // or object with linkage, then look for another declaration with 1430 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1431 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1432 /* Do nothing*/; 1433 else if (R->isFunctionType()) { 1434 if (CurContext->isFunctionOrMethod()) 1435 NameKind = LookupRedeclarationWithLinkage; 1436 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1437 NameKind = LookupRedeclarationWithLinkage; 1438 1439 DC = CurContext; 1440 PrevDecl = LookupName(S, Name, NameKind, true, 1441 D.getDeclSpec().getStorageClassSpec() != 1442 DeclSpec::SCS_static, 1443 D.getIdentifierLoc()); 1444 } else { // Something like "int foo::x;" 1445 DC = computeDeclContext(D.getCXXScopeSpec()); 1446 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1447 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1448 1449 // C++ 7.3.1.2p2: 1450 // Members (including explicit specializations of templates) of a named 1451 // namespace can also be defined outside that namespace by explicit 1452 // qualification of the name being defined, provided that the entity being 1453 // defined was already declared in the namespace and the definition appears 1454 // after the point of declaration in a namespace that encloses the 1455 // declarations namespace. 1456 // 1457 // Note that we only check the context at this point. We don't yet 1458 // have enough information to make sure that PrevDecl is actually 1459 // the declaration we want to match. For example, given: 1460 // 1461 // class X { 1462 // void f(); 1463 // void f(float); 1464 // }; 1465 // 1466 // void X::f(int) { } // ill-formed 1467 // 1468 // In this case, PrevDecl will point to the overload set 1469 // containing the two f's declared in X, but neither of them 1470 // matches. 1471 1472 // First check whether we named the global scope. 1473 if (isa<TranslationUnitDecl>(DC)) { 1474 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1475 << Name << D.getCXXScopeSpec().getRange(); 1476 } else if (!CurContext->Encloses(DC)) { 1477 // The qualifying scope doesn't enclose the original declaration. 1478 // Emit diagnostic based on current scope. 1479 SourceLocation L = D.getIdentifierLoc(); 1480 SourceRange R = D.getCXXScopeSpec().getRange(); 1481 if (isa<FunctionDecl>(CurContext)) 1482 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1483 else 1484 Diag(L, diag::err_invalid_declarator_scope) 1485 << Name << cast<NamedDecl>(DC) << R; 1486 D.setInvalidType(); 1487 } 1488 } 1489 1490 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1491 // Maybe we will complain about the shadowed template parameter. 1492 if (!D.isInvalidType()) 1493 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1494 D.setInvalidType(); 1495 1496 // Just pretend that we didn't see the previous declaration. 1497 PrevDecl = 0; 1498 } 1499 1500 // In C++, the previous declaration we find might be a tag type 1501 // (class or enum). In this case, the new declaration will hide the 1502 // tag type. Note that this does does not apply if we're declaring a 1503 // typedef (C++ [dcl.typedef]p4). 1504 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1505 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1506 PrevDecl = 0; 1507 1508 bool Redeclaration = false; 1509 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1510 if (TemplateParamLists.size()) { 1511 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1512 return DeclPtrTy(); 1513 } 1514 1515 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1516 } else if (R->isFunctionType()) { 1517 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1518 move(TemplateParamLists), 1519 IsFunctionDefinition, Redeclaration); 1520 } else { 1521 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1522 } 1523 1524 if (New == 0) 1525 return DeclPtrTy(); 1526 1527 // If this has an identifier and is not an invalid redeclaration, 1528 // add it to the scope stack. 1529 if (Name && !(Redeclaration && New->isInvalidDecl())) 1530 PushOnScopeChains(New, S); 1531 1532 return DeclPtrTy::make(New); 1533} 1534 1535/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1536/// types into constant array types in certain situations which would otherwise 1537/// be errors (for GCC compatibility). 1538static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1539 ASTContext &Context, 1540 bool &SizeIsNegative) { 1541 // This method tries to turn a variable array into a constant 1542 // array even when the size isn't an ICE. This is necessary 1543 // for compatibility with code that depends on gcc's buggy 1544 // constant expression folding, like struct {char x[(int)(char*)2];} 1545 SizeIsNegative = false; 1546 1547 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1548 QualType Pointee = PTy->getPointeeType(); 1549 QualType FixedType = 1550 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1551 if (FixedType.isNull()) return FixedType; 1552 FixedType = Context.getPointerType(FixedType); 1553 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1554 return FixedType; 1555 } 1556 1557 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1558 if (!VLATy) 1559 return QualType(); 1560 // FIXME: We should probably handle this case 1561 if (VLATy->getElementType()->isVariablyModifiedType()) 1562 return QualType(); 1563 1564 Expr::EvalResult EvalResult; 1565 if (!VLATy->getSizeExpr() || 1566 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1567 !EvalResult.Val.isInt()) 1568 return QualType(); 1569 1570 llvm::APSInt &Res = EvalResult.Val.getInt(); 1571 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1572 return Context.getConstantArrayType(VLATy->getElementType(), 1573 Res, ArrayType::Normal, 0); 1574 1575 SizeIsNegative = true; 1576 return QualType(); 1577} 1578 1579/// \brief Register the given locally-scoped external C declaration so 1580/// that it can be found later for redeclarations 1581void 1582Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1583 Scope *S) { 1584 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1585 "Decl is not a locally-scoped decl!"); 1586 // Note that we have a locally-scoped external with this name. 1587 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1588 1589 if (!PrevDecl) 1590 return; 1591 1592 // If there was a previous declaration of this variable, it may be 1593 // in our identifier chain. Update the identifier chain with the new 1594 // declaration. 1595 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1596 // The previous declaration was found on the identifer resolver 1597 // chain, so remove it from its scope. 1598 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1599 S = S->getParent(); 1600 1601 if (S) 1602 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1603 } 1604} 1605 1606/// \brief Diagnose function specifiers on a declaration of an identifier that 1607/// does not identify a function. 1608void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1609 // FIXME: We should probably indicate the identifier in question to avoid 1610 // confusion for constructs like "inline int a(), b;" 1611 if (D.getDeclSpec().isInlineSpecified()) 1612 Diag(D.getDeclSpec().getInlineSpecLoc(), 1613 diag::err_inline_non_function); 1614 1615 if (D.getDeclSpec().isVirtualSpecified()) 1616 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1617 diag::err_virtual_non_function); 1618 1619 if (D.getDeclSpec().isExplicitSpecified()) 1620 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1621 diag::err_explicit_non_function); 1622} 1623 1624NamedDecl* 1625Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1626 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1627 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1628 if (D.getCXXScopeSpec().isSet()) { 1629 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1630 << D.getCXXScopeSpec().getRange(); 1631 D.setInvalidType(); 1632 // Pretend we didn't see the scope specifier. 1633 DC = 0; 1634 } 1635 1636 if (getLangOptions().CPlusPlus) { 1637 // Check that there are no default arguments (C++ only). 1638 CheckExtraCXXDefaultArguments(D); 1639 } 1640 1641 DiagnoseFunctionSpecifiers(D); 1642 1643 if (D.getDeclSpec().isThreadSpecified()) 1644 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1645 1646 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1647 if (!NewTD) return 0; 1648 1649 if (D.isInvalidType()) 1650 NewTD->setInvalidDecl(); 1651 1652 // Handle attributes prior to checking for duplicates in MergeVarDecl 1653 ProcessDeclAttributes(S, NewTD, D); 1654 // Merge the decl with the existing one if appropriate. If the decl is 1655 // in an outer scope, it isn't the same thing. 1656 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1657 Redeclaration = true; 1658 MergeTypeDefDecl(NewTD, PrevDecl); 1659 } 1660 1661 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1662 // then it shall have block scope. 1663 QualType T = NewTD->getUnderlyingType(); 1664 if (T->isVariablyModifiedType()) { 1665 CurFunctionNeedsScopeChecking = true; 1666 1667 if (S->getFnParent() == 0) { 1668 bool SizeIsNegative; 1669 QualType FixedTy = 1670 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1671 if (!FixedTy.isNull()) { 1672 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1673 NewTD->setUnderlyingType(FixedTy); 1674 } else { 1675 if (SizeIsNegative) 1676 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1677 else if (T->isVariableArrayType()) 1678 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1679 else 1680 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1681 NewTD->setInvalidDecl(); 1682 } 1683 } 1684 } 1685 return NewTD; 1686} 1687 1688/// \brief Determines whether the given declaration is an out-of-scope 1689/// previous declaration. 1690/// 1691/// This routine should be invoked when name lookup has found a 1692/// previous declaration (PrevDecl) that is not in the scope where a 1693/// new declaration by the same name is being introduced. If the new 1694/// declaration occurs in a local scope, previous declarations with 1695/// linkage may still be considered previous declarations (C99 1696/// 6.2.2p4-5, C++ [basic.link]p6). 1697/// 1698/// \param PrevDecl the previous declaration found by name 1699/// lookup 1700/// 1701/// \param DC the context in which the new declaration is being 1702/// declared. 1703/// 1704/// \returns true if PrevDecl is an out-of-scope previous declaration 1705/// for a new delcaration with the same name. 1706static bool 1707isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1708 ASTContext &Context) { 1709 if (!PrevDecl) 1710 return 0; 1711 1712 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1713 // case we need to check each of the overloaded functions. 1714 if (!PrevDecl->hasLinkage()) 1715 return false; 1716 1717 if (Context.getLangOptions().CPlusPlus) { 1718 // C++ [basic.link]p6: 1719 // If there is a visible declaration of an entity with linkage 1720 // having the same name and type, ignoring entities declared 1721 // outside the innermost enclosing namespace scope, the block 1722 // scope declaration declares that same entity and receives the 1723 // linkage of the previous declaration. 1724 DeclContext *OuterContext = DC->getLookupContext(); 1725 if (!OuterContext->isFunctionOrMethod()) 1726 // This rule only applies to block-scope declarations. 1727 return false; 1728 else { 1729 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1730 if (PrevOuterContext->isRecord()) 1731 // We found a member function: ignore it. 1732 return false; 1733 else { 1734 // Find the innermost enclosing namespace for the new and 1735 // previous declarations. 1736 while (!OuterContext->isFileContext()) 1737 OuterContext = OuterContext->getParent(); 1738 while (!PrevOuterContext->isFileContext()) 1739 PrevOuterContext = PrevOuterContext->getParent(); 1740 1741 // The previous declaration is in a different namespace, so it 1742 // isn't the same function. 1743 if (OuterContext->getPrimaryContext() != 1744 PrevOuterContext->getPrimaryContext()) 1745 return false; 1746 } 1747 } 1748 } 1749 1750 return true; 1751} 1752 1753NamedDecl* 1754Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1755 QualType R,NamedDecl* PrevDecl, 1756 bool &Redeclaration) { 1757 DeclarationName Name = GetNameForDeclarator(D); 1758 1759 // Check that there are no default arguments (C++ only). 1760 if (getLangOptions().CPlusPlus) 1761 CheckExtraCXXDefaultArguments(D); 1762 1763 VarDecl *NewVD; 1764 VarDecl::StorageClass SC; 1765 switch (D.getDeclSpec().getStorageClassSpec()) { 1766 default: assert(0 && "Unknown storage class!"); 1767 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1768 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1769 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1770 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1771 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1772 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1773 case DeclSpec::SCS_mutable: 1774 // mutable can only appear on non-static class members, so it's always 1775 // an error here 1776 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1777 D.setInvalidType(); 1778 SC = VarDecl::None; 1779 break; 1780 } 1781 1782 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1783 if (!II) { 1784 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1785 << Name.getAsString(); 1786 return 0; 1787 } 1788 1789 DiagnoseFunctionSpecifiers(D); 1790 1791 if (!DC->isRecord() && S->getFnParent() == 0) { 1792 // C99 6.9p2: The storage-class specifiers auto and register shall not 1793 // appear in the declaration specifiers in an external declaration. 1794 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1795 1796 // If this is a register variable with an asm label specified, then this 1797 // is a GNU extension. 1798 if (SC == VarDecl::Register && D.getAsmLabel()) 1799 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1800 else 1801 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1802 D.setInvalidType(); 1803 } 1804 } 1805 if (DC->isRecord() && !CurContext->isRecord()) { 1806 // This is an out-of-line definition of a static data member. 1807 if (SC == VarDecl::Static) { 1808 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1809 diag::err_static_out_of_line) 1810 << CodeModificationHint::CreateRemoval( 1811 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1812 } else if (SC == VarDecl::None) 1813 SC = VarDecl::Static; 1814 } 1815 if (SC == VarDecl::Static) { 1816 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 1817 if (RD->isLocalClass()) 1818 Diag(D.getIdentifierLoc(), 1819 diag::err_static_data_member_not_allowed_in_local_class) 1820 << Name << RD->getDeclName(); 1821 } 1822 } 1823 1824 1825 // The variable can not 1826 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1827 II, R, SC, 1828 // FIXME: Move to DeclGroup... 1829 D.getDeclSpec().getSourceRange().getBegin()); 1830 1831 if (D.isInvalidType()) 1832 NewVD->setInvalidDecl(); 1833 1834 if (D.getDeclSpec().isThreadSpecified()) { 1835 if (NewVD->hasLocalStorage()) 1836 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1837 else if (!Context.Target.isTLSSupported()) 1838 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1839 else 1840 NewVD->setThreadSpecified(true); 1841 } 1842 1843 // Set the lexical context. If the declarator has a C++ scope specifier, the 1844 // lexical context will be different from the semantic context. 1845 NewVD->setLexicalDeclContext(CurContext); 1846 1847 // Handle attributes prior to checking for duplicates in MergeVarDecl 1848 ProcessDeclAttributes(S, NewVD, D); 1849 1850 // Handle GNU asm-label extension (encoded as an attribute). 1851 if (Expr *E = (Expr*) D.getAsmLabel()) { 1852 // The parser guarantees this is a string. 1853 StringLiteral *SE = cast<StringLiteral>(E); 1854 NewVD->addAttr(Context, 1855 ::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1856 SE->getByteLength()))); 1857 } 1858 1859 // If name lookup finds a previous declaration that is not in the 1860 // same scope as the new declaration, this may still be an 1861 // acceptable redeclaration. 1862 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1863 !(NewVD->hasLinkage() && 1864 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1865 PrevDecl = 0; 1866 1867 // Merge the decl with the existing one if appropriate. 1868 if (PrevDecl) { 1869 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1870 // The user tried to define a non-static data member 1871 // out-of-line (C++ [dcl.meaning]p1). 1872 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1873 << D.getCXXScopeSpec().getRange(); 1874 PrevDecl = 0; 1875 NewVD->setInvalidDecl(); 1876 } 1877 } else if (D.getCXXScopeSpec().isSet()) { 1878 // No previous declaration in the qualifying scope. 1879 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1880 << Name << D.getCXXScopeSpec().getRange(); 1881 NewVD->setInvalidDecl(); 1882 } 1883 1884 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1885 1886 // If this is a locally-scoped extern C variable, update the map of 1887 // such variables. 1888 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1889 !NewVD->isInvalidDecl()) 1890 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1891 1892 return NewVD; 1893} 1894 1895/// \brief Perform semantic checking on a newly-created variable 1896/// declaration. 1897/// 1898/// This routine performs all of the type-checking required for a 1899/// variable declaration once it has been built. It is used both to 1900/// check variables after they have been parsed and their declarators 1901/// have been translated into a declaration, and to check variables 1902/// that have been instantiated from a template. 1903/// 1904/// Sets NewVD->isInvalidDecl() if an error was encountered. 1905void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1906 bool &Redeclaration) { 1907 // If the decl is already known invalid, don't check it. 1908 if (NewVD->isInvalidDecl()) 1909 return; 1910 1911 QualType T = NewVD->getType(); 1912 1913 if (T->isObjCInterfaceType()) { 1914 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1915 return NewVD->setInvalidDecl(); 1916 } 1917 1918 // The variable can not have an abstract class type. 1919 if (RequireNonAbstractType(NewVD->getLocation(), T, 1920 diag::err_abstract_type_in_decl, 1921 AbstractVariableType)) 1922 return NewVD->setInvalidDecl(); 1923 1924 // Emit an error if an address space was applied to decl with local storage. 1925 // This includes arrays of objects with address space qualifiers, but not 1926 // automatic variables that point to other address spaces. 1927 // ISO/IEC TR 18037 S5.1.2 1928 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1929 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1930 return NewVD->setInvalidDecl(); 1931 } 1932 1933 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1934 && !NewVD->hasAttr<BlocksAttr>(Context)) 1935 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1936 1937 bool isVM = T->isVariablyModifiedType(); 1938 if (isVM || NewVD->hasAttr<CleanupAttr>(Context)) 1939 CurFunctionNeedsScopeChecking = true; 1940 1941 if ((isVM && NewVD->hasLinkage()) || 1942 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1943 bool SizeIsNegative; 1944 QualType FixedTy = 1945 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1946 1947 if (FixedTy.isNull() && T->isVariableArrayType()) { 1948 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1949 // FIXME: This won't give the correct result for 1950 // int a[10][n]; 1951 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1952 1953 if (NewVD->isFileVarDecl()) 1954 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1955 << SizeRange; 1956 else if (NewVD->getStorageClass() == VarDecl::Static) 1957 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1958 << SizeRange; 1959 else 1960 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1961 << SizeRange; 1962 return NewVD->setInvalidDecl(); 1963 } 1964 1965 if (FixedTy.isNull()) { 1966 if (NewVD->isFileVarDecl()) 1967 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1968 else 1969 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1970 return NewVD->setInvalidDecl(); 1971 } 1972 1973 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1974 NewVD->setType(FixedTy); 1975 } 1976 1977 if (!PrevDecl && NewVD->isExternC(Context)) { 1978 // Since we did not find anything by this name and we're declaring 1979 // an extern "C" variable, look for a non-visible extern "C" 1980 // declaration with the same name. 1981 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1982 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1983 if (Pos != LocallyScopedExternalDecls.end()) 1984 PrevDecl = Pos->second; 1985 } 1986 1987 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1988 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1989 << T; 1990 return NewVD->setInvalidDecl(); 1991 } 1992 1993 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>(Context)) { 1994 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 1995 return NewVD->setInvalidDecl(); 1996 } 1997 1998 if (isVM && NewVD->hasAttr<BlocksAttr>(Context)) { 1999 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2000 return NewVD->setInvalidDecl(); 2001 } 2002 2003 if (PrevDecl) { 2004 Redeclaration = true; 2005 MergeVarDecl(NewVD, PrevDecl); 2006 } 2007} 2008 2009NamedDecl* 2010Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2011 QualType R, NamedDecl* PrevDecl, 2012 MultiTemplateParamsArg TemplateParamLists, 2013 bool IsFunctionDefinition, bool &Redeclaration) { 2014 assert(R.getTypePtr()->isFunctionType()); 2015 2016 DeclarationName Name = GetNameForDeclarator(D); 2017 FunctionDecl::StorageClass SC = FunctionDecl::None; 2018 switch (D.getDeclSpec().getStorageClassSpec()) { 2019 default: assert(0 && "Unknown storage class!"); 2020 case DeclSpec::SCS_auto: 2021 case DeclSpec::SCS_register: 2022 case DeclSpec::SCS_mutable: 2023 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2024 diag::err_typecheck_sclass_func); 2025 D.setInvalidType(); 2026 break; 2027 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2028 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2029 case DeclSpec::SCS_static: { 2030 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2031 // C99 6.7.1p5: 2032 // The declaration of an identifier for a function that has 2033 // block scope shall have no explicit storage-class specifier 2034 // other than extern 2035 // See also (C++ [dcl.stc]p4). 2036 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2037 diag::err_static_block_func); 2038 SC = FunctionDecl::None; 2039 } else 2040 SC = FunctionDecl::Static; 2041 break; 2042 } 2043 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2044 } 2045 2046 if (D.getDeclSpec().isThreadSpecified()) 2047 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2048 2049 bool isInline = D.getDeclSpec().isInlineSpecified(); 2050 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2051 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2052 2053 // Check that the return type is not an abstract class type. 2054 // For record types, this is done by the AbstractClassUsageDiagnoser once 2055 // the class has been completely parsed. 2056 if (!DC->isRecord() && 2057 RequireNonAbstractType(D.getIdentifierLoc(), 2058 R->getAsFunctionType()->getResultType(), 2059 diag::err_abstract_type_in_decl, 2060 AbstractReturnType)) 2061 D.setInvalidType(); 2062 2063 // Do not allow returning a objc interface by-value. 2064 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2065 Diag(D.getIdentifierLoc(), 2066 diag::err_object_cannot_be_passed_returned_by_value) << 0 2067 << R->getAsFunctionType()->getResultType(); 2068 D.setInvalidType(); 2069 } 2070 2071 // Check that we can declare a template here. 2072 if (TemplateParamLists.size() && 2073 CheckTemplateDeclScope(S, TemplateParamLists)) 2074 return 0; 2075 2076 bool isVirtualOkay = false; 2077 FunctionDecl *NewFD; 2078 if (D.getKind() == Declarator::DK_Constructor) { 2079 // This is a C++ constructor declaration. 2080 assert(DC->isRecord() && 2081 "Constructors can only be declared in a member context"); 2082 2083 R = CheckConstructorDeclarator(D, R, SC); 2084 2085 // Create the new declaration 2086 NewFD = CXXConstructorDecl::Create(Context, 2087 cast<CXXRecordDecl>(DC), 2088 D.getIdentifierLoc(), Name, R, 2089 isExplicit, isInline, 2090 /*isImplicitlyDeclared=*/false); 2091 } else if (D.getKind() == Declarator::DK_Destructor) { 2092 // This is a C++ destructor declaration. 2093 if (DC->isRecord()) { 2094 R = CheckDestructorDeclarator(D, SC); 2095 2096 NewFD = CXXDestructorDecl::Create(Context, 2097 cast<CXXRecordDecl>(DC), 2098 D.getIdentifierLoc(), Name, R, 2099 isInline, 2100 /*isImplicitlyDeclared=*/false); 2101 2102 isVirtualOkay = true; 2103 } else { 2104 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2105 2106 // Create a FunctionDecl to satisfy the function definition parsing 2107 // code path. 2108 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2109 Name, R, SC, isInline, 2110 /*hasPrototype=*/true, 2111 // FIXME: Move to DeclGroup... 2112 D.getDeclSpec().getSourceRange().getBegin()); 2113 D.setInvalidType(); 2114 } 2115 } else if (D.getKind() == Declarator::DK_Conversion) { 2116 if (!DC->isRecord()) { 2117 Diag(D.getIdentifierLoc(), 2118 diag::err_conv_function_not_member); 2119 return 0; 2120 } 2121 2122 CheckConversionDeclarator(D, R, SC); 2123 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2124 D.getIdentifierLoc(), Name, R, 2125 isInline, isExplicit); 2126 2127 isVirtualOkay = true; 2128 } else if (DC->isRecord()) { 2129 // If the of the function is the same as the name of the record, then this 2130 // must be an invalid constructor that has a return type. 2131 // (The parser checks for a return type and makes the declarator a 2132 // constructor if it has no return type). 2133 // must have an invalid constructor that has a return type 2134 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2135 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2136 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2137 << SourceRange(D.getIdentifierLoc()); 2138 return 0; 2139 } 2140 2141 // This is a C++ method declaration. 2142 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2143 D.getIdentifierLoc(), Name, R, 2144 (SC == FunctionDecl::Static), isInline); 2145 2146 isVirtualOkay = (SC != FunctionDecl::Static); 2147 } else { 2148 // Determine whether the function was written with a 2149 // prototype. This true when: 2150 // - we're in C++ (where every function has a prototype), 2151 // - there is a prototype in the declarator, or 2152 // - the type R of the function is some kind of typedef or other reference 2153 // to a type name (which eventually refers to a function type). 2154 bool HasPrototype = 2155 getLangOptions().CPlusPlus || 2156 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2157 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2158 2159 NewFD = FunctionDecl::Create(Context, DC, 2160 D.getIdentifierLoc(), 2161 Name, R, SC, isInline, HasPrototype, 2162 // FIXME: Move to DeclGroup... 2163 D.getDeclSpec().getSourceRange().getBegin()); 2164 } 2165 2166 if (D.isInvalidType()) 2167 NewFD->setInvalidDecl(); 2168 2169 // Set the lexical context. If the declarator has a C++ 2170 // scope specifier, the lexical context will be different 2171 // from the semantic context. 2172 NewFD->setLexicalDeclContext(CurContext); 2173 2174 // If there is a template parameter list, then we are dealing with a 2175 // template declaration or specialization. 2176 FunctionTemplateDecl *FunctionTemplate = 0; 2177 if (TemplateParamLists.size()) { 2178 // FIXME: member templates! 2179 TemplateParameterList *TemplateParams 2180 = static_cast<TemplateParameterList *>(*TemplateParamLists.release()); 2181 2182 if (TemplateParams->size() > 0) { 2183 // This is a function template 2184 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2185 NewFD->getLocation(), 2186 Name, TemplateParams, 2187 NewFD); 2188 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2189 } else { 2190 // FIXME: Handle function template specializations 2191 } 2192 } 2193 2194 // C++ [dcl.fct.spec]p5: 2195 // The virtual specifier shall only be used in declarations of 2196 // nonstatic class member functions that appear within a 2197 // member-specification of a class declaration; see 10.3. 2198 // 2199 if (isVirtual && !NewFD->isInvalidDecl()) { 2200 if (!isVirtualOkay) { 2201 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2202 diag::err_virtual_non_function); 2203 } else if (!CurContext->isRecord()) { 2204 // 'virtual' was specified outside of the class. 2205 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2206 << CodeModificationHint::CreateRemoval( 2207 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2208 } else { 2209 // Okay: Add virtual to the method. 2210 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2211 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2212 CurClass->setAggregate(false); 2213 CurClass->setPOD(false); 2214 CurClass->setPolymorphic(true); 2215 CurClass->setHasTrivialConstructor(false); 2216 } 2217 } 2218 2219 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2220 // Look for virtual methods in base classes that this method might override. 2221 2222 BasePaths Paths; 2223 if (LookupInBases(cast<CXXRecordDecl>(DC), 2224 MemberLookupCriteria(NewMD), Paths)) { 2225 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2226 E = Paths.found_decls_end(); I != E; ++I) { 2227 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2228 if (!CheckOverridingFunctionReturnType(NewMD, OldMD)) 2229 NewMD->addOverriddenMethod(OldMD); 2230 } 2231 } 2232 } 2233 } 2234 2235 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2236 !CurContext->isRecord()) { 2237 // C++ [class.static]p1: 2238 // A data or function member of a class may be declared static 2239 // in a class definition, in which case it is a static member of 2240 // the class. 2241 2242 // Complain about the 'static' specifier if it's on an out-of-line 2243 // member function definition. 2244 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2245 diag::err_static_out_of_line) 2246 << CodeModificationHint::CreateRemoval( 2247 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2248 } 2249 2250 // Handle GNU asm-label extension (encoded as an attribute). 2251 if (Expr *E = (Expr*) D.getAsmLabel()) { 2252 // The parser guarantees this is a string. 2253 StringLiteral *SE = cast<StringLiteral>(E); 2254 NewFD->addAttr(Context, 2255 ::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2256 SE->getByteLength()))); 2257 } 2258 2259 // Copy the parameter declarations from the declarator D to the function 2260 // declaration NewFD, if they are available. First scavenge them into Params. 2261 llvm::SmallVector<ParmVarDecl*, 16> Params; 2262 if (D.getNumTypeObjects() > 0) { 2263 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2264 2265 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2266 // function that takes no arguments, not a function that takes a 2267 // single void argument. 2268 // We let through "const void" here because Sema::GetTypeForDeclarator 2269 // already checks for that case. 2270 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2271 FTI.ArgInfo[0].Param && 2272 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2273 // Empty arg list, don't push any params. 2274 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2275 2276 // In C++, the empty parameter-type-list must be spelled "void"; a 2277 // typedef of void is not permitted. 2278 if (getLangOptions().CPlusPlus && 2279 Param->getType().getUnqualifiedType() != Context.VoidTy) 2280 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2281 // FIXME: Leaks decl? 2282 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2283 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2284 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2285 } 2286 2287 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2288 // When we're declaring a function with a typedef, typeof, etc as in the 2289 // following example, we'll need to synthesize (unnamed) 2290 // parameters for use in the declaration. 2291 // 2292 // @code 2293 // typedef void fn(int); 2294 // fn f; 2295 // @endcode 2296 2297 // Synthesize a parameter for each argument type. 2298 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2299 AE = FT->arg_type_end(); AI != AE; ++AI) { 2300 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2301 SourceLocation(), 0, 2302 *AI, VarDecl::None, 0); 2303 Param->setImplicit(); 2304 Params.push_back(Param); 2305 } 2306 } else { 2307 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2308 "Should not need args for typedef of non-prototype fn"); 2309 } 2310 // Finally, we know we have the right number of parameters, install them. 2311 NewFD->setParams(Context, Params.data(), Params.size()); 2312 2313 // If name lookup finds a previous declaration that is not in the 2314 // same scope as the new declaration, this may still be an 2315 // acceptable redeclaration. 2316 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2317 !(NewFD->hasLinkage() && 2318 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2319 PrevDecl = 0; 2320 2321 // Perform semantic checking on the function declaration. 2322 bool OverloadableAttrRequired = false; // FIXME: HACK! 2323 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2324 /*FIXME:*/OverloadableAttrRequired); 2325 2326 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2327 // An out-of-line member function declaration must also be a 2328 // definition (C++ [dcl.meaning]p1). 2329 if (!IsFunctionDefinition) { 2330 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2331 << D.getCXXScopeSpec().getRange(); 2332 NewFD->setInvalidDecl(); 2333 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2334 // The user tried to provide an out-of-line definition for a 2335 // function that is a member of a class or namespace, but there 2336 // was no such member function declared (C++ [class.mfct]p2, 2337 // C++ [namespace.memdef]p2). For example: 2338 // 2339 // class X { 2340 // void f() const; 2341 // }; 2342 // 2343 // void X::f() { } // ill-formed 2344 // 2345 // Complain about this problem, and attempt to suggest close 2346 // matches (e.g., those that differ only in cv-qualifiers and 2347 // whether the parameter types are references). 2348 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2349 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2350 NewFD->setInvalidDecl(); 2351 2352 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2353 true); 2354 assert(!Prev.isAmbiguous() && 2355 "Cannot have an ambiguity in previous-declaration lookup"); 2356 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2357 Func != FuncEnd; ++Func) { 2358 if (isa<FunctionDecl>(*Func) && 2359 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2360 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2361 } 2362 2363 PrevDecl = 0; 2364 } 2365 } 2366 2367 // Handle attributes. We need to have merged decls when handling attributes 2368 // (for example to check for conflicts, etc). 2369 // FIXME: This needs to happen before we merge declarations. Then, 2370 // let attribute merging cope with attribute conflicts. 2371 ProcessDeclAttributes(S, NewFD, D); 2372 AddKnownFunctionAttributes(NewFD); 2373 2374 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>(Context)) { 2375 // If a function name is overloadable in C, then every function 2376 // with that name must be marked "overloadable". 2377 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2378 << Redeclaration << NewFD; 2379 if (PrevDecl) 2380 Diag(PrevDecl->getLocation(), 2381 diag::note_attribute_overloadable_prev_overload); 2382 NewFD->addAttr(Context, ::new (Context) OverloadableAttr()); 2383 } 2384 2385 // If this is a locally-scoped extern C function, update the 2386 // map of such names. 2387 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2388 && !NewFD->isInvalidDecl()) 2389 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2390 2391 // Set this FunctionDecl's range up to the right paren. 2392 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2393 2394 if (FunctionTemplate && NewFD->isInvalidDecl()) 2395 FunctionTemplate->setInvalidDecl(); 2396 2397 if (FunctionTemplate) 2398 return FunctionTemplate; 2399 2400 return NewFD; 2401} 2402 2403/// \brief Perform semantic checking of a new function declaration. 2404/// 2405/// Performs semantic analysis of the new function declaration 2406/// NewFD. This routine performs all semantic checking that does not 2407/// require the actual declarator involved in the declaration, and is 2408/// used both for the declaration of functions as they are parsed 2409/// (called via ActOnDeclarator) and for the declaration of functions 2410/// that have been instantiated via C++ template instantiation (called 2411/// via InstantiateDecl). 2412/// 2413/// This sets NewFD->isInvalidDecl() to true if there was an error. 2414void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2415 bool &Redeclaration, 2416 bool &OverloadableAttrRequired) { 2417 // If NewFD is already known erroneous, don't do any of this checking. 2418 if (NewFD->isInvalidDecl()) 2419 return; 2420 2421 if (NewFD->getResultType()->isVariablyModifiedType()) { 2422 // Functions returning a variably modified type violate C99 6.7.5.2p2 2423 // because all functions have linkage. 2424 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2425 return NewFD->setInvalidDecl(); 2426 } 2427 2428 // Semantic checking for this function declaration (in isolation). 2429 if (getLangOptions().CPlusPlus) { 2430 // C++-specific checks. 2431 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2432 CheckConstructor(Constructor); 2433 } else if (isa<CXXDestructorDecl>(NewFD)) { 2434 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2435 Record->setUserDeclaredDestructor(true); 2436 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2437 // user-defined destructor. 2438 Record->setPOD(false); 2439 2440 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2441 // declared destructor. 2442 Record->setHasTrivialDestructor(false); 2443 } else if (CXXConversionDecl *Conversion 2444 = dyn_cast<CXXConversionDecl>(NewFD)) 2445 ActOnConversionDeclarator(Conversion); 2446 2447 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2448 if (NewFD->isOverloadedOperator() && 2449 CheckOverloadedOperatorDeclaration(NewFD)) 2450 return NewFD->setInvalidDecl(); 2451 } 2452 2453 // C99 6.7.4p6: 2454 // [... ] For a function with external linkage, the following 2455 // restrictions apply: [...] If all of the file scope declarations 2456 // for a function in a translation unit include the inline 2457 // function specifier without extern, then the definition in that 2458 // translation unit is an inline definition. An inline definition 2459 // does not provide an external definition for the function, and 2460 // does not forbid an external definition in another translation 2461 // unit. 2462 // 2463 // Here we determine whether this function, in isolation, would be a 2464 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2465 // previous declarations. 2466 if (NewFD->isInline() && getLangOptions().C99 && 2467 NewFD->getStorageClass() == FunctionDecl::None && 2468 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2469 NewFD->setC99InlineDefinition(true); 2470 2471 // Check for a previous declaration of this name. 2472 if (!PrevDecl && NewFD->isExternC(Context)) { 2473 // Since we did not find anything by this name and we're declaring 2474 // an extern "C" function, look for a non-visible extern "C" 2475 // declaration with the same name. 2476 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2477 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2478 if (Pos != LocallyScopedExternalDecls.end()) 2479 PrevDecl = Pos->second; 2480 } 2481 2482 // Merge or overload the declaration with an existing declaration of 2483 // the same name, if appropriate. 2484 if (PrevDecl) { 2485 // Determine whether NewFD is an overload of PrevDecl or 2486 // a declaration that requires merging. If it's an overload, 2487 // there's no more work to do here; we'll just add the new 2488 // function to the scope. 2489 OverloadedFunctionDecl::function_iterator MatchedDecl; 2490 2491 if (!getLangOptions().CPlusPlus && 2492 AllowOverloadingOfFunction(PrevDecl, Context)) { 2493 OverloadableAttrRequired = true; 2494 2495 // Functions marked "overloadable" must have a prototype (that 2496 // we can't get through declaration merging). 2497 if (!NewFD->getType()->getAsFunctionProtoType()) { 2498 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2499 << NewFD; 2500 Redeclaration = true; 2501 2502 // Turn this into a variadic function with no parameters. 2503 QualType R = Context.getFunctionType( 2504 NewFD->getType()->getAsFunctionType()->getResultType(), 2505 0, 0, true, 0); 2506 NewFD->setType(R); 2507 return NewFD->setInvalidDecl(); 2508 } 2509 } 2510 2511 if (PrevDecl && 2512 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2513 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2514 !isa<UsingDecl>(PrevDecl)) { 2515 Redeclaration = true; 2516 Decl *OldDecl = PrevDecl; 2517 2518 // If PrevDecl was an overloaded function, extract the 2519 // FunctionDecl that matched. 2520 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2521 OldDecl = *MatchedDecl; 2522 2523 // NewFD and OldDecl represent declarations that need to be 2524 // merged. 2525 if (MergeFunctionDecl(NewFD, OldDecl)) 2526 return NewFD->setInvalidDecl(); 2527 2528 if (FunctionTemplateDecl *OldTemplateDecl 2529 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2530 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2531 else 2532 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2533 } 2534 } 2535 2536 // In C++, check default arguments now that we have merged decls. Unless 2537 // the lexical context is the class, because in this case this is done 2538 // during delayed parsing anyway. 2539 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2540 CheckCXXDefaultArguments(NewFD); 2541} 2542 2543bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2544 // FIXME: Need strict checking. In C89, we need to check for 2545 // any assignment, increment, decrement, function-calls, or 2546 // commas outside of a sizeof. In C99, it's the same list, 2547 // except that the aforementioned are allowed in unevaluated 2548 // expressions. Everything else falls under the 2549 // "may accept other forms of constant expressions" exception. 2550 // (We never end up here for C++, so the constant expression 2551 // rules there don't matter.) 2552 if (Init->isConstantInitializer(Context)) 2553 return false; 2554 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2555 << Init->getSourceRange(); 2556 return true; 2557} 2558 2559void Sema::AddInitializerToDecl(DeclPtrTy dcl, FullExprArg init) { 2560 AddInitializerToDecl(dcl, init.release(), /*DirectInit=*/false); 2561} 2562 2563/// AddInitializerToDecl - Adds the initializer Init to the 2564/// declaration dcl. If DirectInit is true, this is C++ direct 2565/// initialization rather than copy initialization. 2566void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2567 Decl *RealDecl = dcl.getAs<Decl>(); 2568 // If there is no declaration, there was an error parsing it. Just ignore 2569 // the initializer. 2570 if (RealDecl == 0) 2571 return; 2572 2573 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2574 // With declarators parsed the way they are, the parser cannot 2575 // distinguish between a normal initializer and a pure-specifier. 2576 // Thus this grotesque test. 2577 IntegerLiteral *IL; 2578 Expr *Init = static_cast<Expr *>(init.get()); 2579 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2580 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2581 if (Method->isVirtualAsWritten()) { 2582 Method->setPure(); 2583 2584 // A class is abstract if at least one function is pure virtual. 2585 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2586 } else if (!Method->isInvalidDecl()) { 2587 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2588 << Method->getDeclName() << Init->getSourceRange(); 2589 Method->setInvalidDecl(); 2590 } 2591 } else { 2592 Diag(Method->getLocation(), diag::err_member_function_initialization) 2593 << Method->getDeclName() << Init->getSourceRange(); 2594 Method->setInvalidDecl(); 2595 } 2596 return; 2597 } 2598 2599 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2600 if (!VDecl) { 2601 if (getLangOptions().CPlusPlus && 2602 RealDecl->getLexicalDeclContext()->isRecord() && 2603 isa<NamedDecl>(RealDecl)) 2604 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2605 << cast<NamedDecl>(RealDecl)->getDeclName(); 2606 else 2607 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2608 RealDecl->setInvalidDecl(); 2609 return; 2610 } 2611 2612 if (!VDecl->getType()->isArrayType() && 2613 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2614 diag::err_typecheck_decl_incomplete_type)) { 2615 RealDecl->setInvalidDecl(); 2616 return; 2617 } 2618 2619 const VarDecl *Def = 0; 2620 if (VDecl->getDefinition(Def)) { 2621 Diag(VDecl->getLocation(), diag::err_redefinition) 2622 << VDecl->getDeclName(); 2623 Diag(Def->getLocation(), diag::note_previous_definition); 2624 VDecl->setInvalidDecl(); 2625 return; 2626 } 2627 2628 // Take ownership of the expression, now that we're sure we have somewhere 2629 // to put it. 2630 Expr *Init = init.takeAs<Expr>(); 2631 assert(Init && "missing initializer"); 2632 2633 // Get the decls type and save a reference for later, since 2634 // CheckInitializerTypes may change it. 2635 QualType DclT = VDecl->getType(), SavT = DclT; 2636 if (VDecl->isBlockVarDecl()) { 2637 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2638 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2639 VDecl->setInvalidDecl(); 2640 } else if (!VDecl->isInvalidDecl()) { 2641 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2642 VDecl->getDeclName(), DirectInit)) 2643 VDecl->setInvalidDecl(); 2644 2645 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2646 // Don't check invalid declarations to avoid emitting useless diagnostics. 2647 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2648 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2649 CheckForConstantInitializer(Init, DclT); 2650 } 2651 } 2652 } else if (VDecl->isStaticDataMember() && 2653 VDecl->getLexicalDeclContext()->isRecord()) { 2654 // This is an in-class initialization for a static data member, e.g., 2655 // 2656 // struct S { 2657 // static const int value = 17; 2658 // }; 2659 2660 // Attach the initializer 2661 VDecl->setInit(Context, Init); 2662 2663 // C++ [class.mem]p4: 2664 // A member-declarator can contain a constant-initializer only 2665 // if it declares a static member (9.4) of const integral or 2666 // const enumeration type, see 9.4.2. 2667 QualType T = VDecl->getType(); 2668 if (!T->isDependentType() && 2669 (!Context.getCanonicalType(T).isConstQualified() || 2670 !T->isIntegralType())) { 2671 Diag(VDecl->getLocation(), diag::err_member_initialization) 2672 << VDecl->getDeclName() << Init->getSourceRange(); 2673 VDecl->setInvalidDecl(); 2674 } else { 2675 // C++ [class.static.data]p4: 2676 // If a static data member is of const integral or const 2677 // enumeration type, its declaration in the class definition 2678 // can specify a constant-initializer which shall be an 2679 // integral constant expression (5.19). 2680 if (!Init->isTypeDependent() && 2681 !Init->getType()->isIntegralType()) { 2682 // We have a non-dependent, non-integral or enumeration type. 2683 Diag(Init->getSourceRange().getBegin(), 2684 diag::err_in_class_initializer_non_integral_type) 2685 << Init->getType() << Init->getSourceRange(); 2686 VDecl->setInvalidDecl(); 2687 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2688 // Check whether the expression is a constant expression. 2689 llvm::APSInt Value; 2690 SourceLocation Loc; 2691 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2692 Diag(Loc, diag::err_in_class_initializer_non_constant) 2693 << Init->getSourceRange(); 2694 VDecl->setInvalidDecl(); 2695 } else if (!VDecl->getType()->isDependentType()) 2696 ImpCastExprToType(Init, VDecl->getType()); 2697 } 2698 } 2699 } else if (VDecl->isFileVarDecl()) { 2700 if (VDecl->getStorageClass() == VarDecl::Extern) 2701 Diag(VDecl->getLocation(), diag::warn_extern_init); 2702 if (!VDecl->isInvalidDecl()) 2703 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2704 VDecl->getDeclName(), DirectInit)) 2705 VDecl->setInvalidDecl(); 2706 2707 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2708 // Don't check invalid declarations to avoid emitting useless diagnostics. 2709 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2710 // C99 6.7.8p4. All file scoped initializers need to be constant. 2711 CheckForConstantInitializer(Init, DclT); 2712 } 2713 } 2714 // If the type changed, it means we had an incomplete type that was 2715 // completed by the initializer. For example: 2716 // int ary[] = { 1, 3, 5 }; 2717 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2718 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2719 VDecl->setType(DclT); 2720 Init->setType(DclT); 2721 } 2722 2723 // Attach the initializer to the decl. 2724 VDecl->setInit(Context, Init); 2725 2726 // If the previous declaration of VDecl was a tentative definition, 2727 // remove it from the set of tentative definitions. 2728 if (VDecl->getPreviousDeclaration() && 2729 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2730 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2731 = TentativeDefinitions.find(VDecl->getDeclName()); 2732 assert(Pos != TentativeDefinitions.end() && 2733 "Unrecorded tentative definition?"); 2734 TentativeDefinitions.erase(Pos); 2735 } 2736 2737 return; 2738} 2739 2740void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2741 Decl *RealDecl = dcl.getAs<Decl>(); 2742 2743 // If there is no declaration, there was an error parsing it. Just ignore it. 2744 if (RealDecl == 0) 2745 return; 2746 2747 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2748 QualType Type = Var->getType(); 2749 2750 // Record tentative definitions. 2751 if (Var->isTentativeDefinition(Context)) 2752 TentativeDefinitions[Var->getDeclName()] = Var; 2753 2754 // C++ [dcl.init.ref]p3: 2755 // The initializer can be omitted for a reference only in a 2756 // parameter declaration (8.3.5), in the declaration of a 2757 // function return type, in the declaration of a class member 2758 // within its class declaration (9.2), and where the extern 2759 // specifier is explicitly used. 2760 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2761 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2762 << Var->getDeclName() 2763 << SourceRange(Var->getLocation(), Var->getLocation()); 2764 Var->setInvalidDecl(); 2765 return; 2766 } 2767 2768 // C++ [dcl.init]p9: 2769 // 2770 // If no initializer is specified for an object, and the object 2771 // is of (possibly cv-qualified) non-POD class type (or array 2772 // thereof), the object shall be default-initialized; if the 2773 // object is of const-qualified type, the underlying class type 2774 // shall have a user-declared default constructor. 2775 if (getLangOptions().CPlusPlus) { 2776 QualType InitType = Type; 2777 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2778 InitType = Array->getElementType(); 2779 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 2780 InitType->isRecordType() && !InitType->isDependentType()) { 2781 CXXRecordDecl *RD = 2782 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2783 CXXConstructorDecl *Constructor = 0; 2784 if (!RequireCompleteType(Var->getLocation(), InitType, 2785 diag::err_invalid_incomplete_type_use)) 2786 Constructor 2787 = PerformInitializationByConstructor(InitType, 0, 0, 2788 Var->getLocation(), 2789 SourceRange(Var->getLocation(), 2790 Var->getLocation()), 2791 Var->getDeclName(), 2792 IK_Default); 2793 if (!Constructor) 2794 Var->setInvalidDecl(); 2795 else { 2796 if (!RD->hasTrivialConstructor()) 2797 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2798 // FIXME. Must do all that is needed to destroy the object 2799 // on scope exit. For now, just mark the destructor as used. 2800 MarcDestructorReferenced(Var->getLocation(), InitType); 2801 } 2802 } 2803 } 2804 2805#if 0 2806 // FIXME: Temporarily disabled because we are not properly parsing 2807 // linkage specifications on declarations, e.g., 2808 // 2809 // extern "C" const CGPoint CGPointerZero; 2810 // 2811 // C++ [dcl.init]p9: 2812 // 2813 // If no initializer is specified for an object, and the 2814 // object is of (possibly cv-qualified) non-POD class type (or 2815 // array thereof), the object shall be default-initialized; if 2816 // the object is of const-qualified type, the underlying class 2817 // type shall have a user-declared default 2818 // constructor. Otherwise, if no initializer is specified for 2819 // an object, the object and its subobjects, if any, have an 2820 // indeterminate initial value; if the object or any of its 2821 // subobjects are of const-qualified type, the program is 2822 // ill-formed. 2823 // 2824 // This isn't technically an error in C, so we don't diagnose it. 2825 // 2826 // FIXME: Actually perform the POD/user-defined default 2827 // constructor check. 2828 if (getLangOptions().CPlusPlus && 2829 Context.getCanonicalType(Type).isConstQualified() && 2830 !Var->hasExternalStorage()) 2831 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2832 << Var->getName() 2833 << SourceRange(Var->getLocation(), Var->getLocation()); 2834#endif 2835 } 2836} 2837 2838Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 2839 DeclPtrTy *Group, 2840 unsigned NumDecls) { 2841 llvm::SmallVector<Decl*, 8> Decls; 2842 2843 if (DS.isTypeSpecOwned()) 2844 Decls.push_back((Decl*)DS.getTypeRep()); 2845 2846 for (unsigned i = 0; i != NumDecls; ++i) 2847 if (Decl *D = Group[i].getAs<Decl>()) 2848 Decls.push_back(D); 2849 2850 // Perform semantic analysis that depends on having fully processed both 2851 // the declarator and initializer. 2852 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2853 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2854 if (!IDecl) 2855 continue; 2856 QualType T = IDecl->getType(); 2857 2858 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2859 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2860 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2861 if (!IDecl->isInvalidDecl() && 2862 RequireCompleteType(IDecl->getLocation(), T, 2863 diag::err_typecheck_decl_incomplete_type)) 2864 IDecl->setInvalidDecl(); 2865 } 2866 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2867 // object that has file scope without an initializer, and without a 2868 // storage-class specifier or with the storage-class specifier "static", 2869 // constitutes a tentative definition. Note: A tentative definition with 2870 // external linkage is valid (C99 6.2.2p5). 2871 if (IDecl->isTentativeDefinition(Context)) { 2872 QualType CheckType = T; 2873 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2874 2875 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2876 if (ArrayT) { 2877 CheckType = ArrayT->getElementType(); 2878 DiagID = diag::err_illegal_decl_array_incomplete_type; 2879 } 2880 2881 if (IDecl->isInvalidDecl()) { 2882 // Do nothing with invalid declarations 2883 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2884 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2885 // C99 6.9.2p3: If the declaration of an identifier for an object is 2886 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2887 // declared type shall not be an incomplete type. 2888 IDecl->setInvalidDecl(); 2889 } 2890 } 2891 } 2892 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2893 Decls.data(), Decls.size())); 2894} 2895 2896 2897/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2898/// to introduce parameters into function prototype scope. 2899Sema::DeclPtrTy 2900Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2901 const DeclSpec &DS = D.getDeclSpec(); 2902 2903 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2904 VarDecl::StorageClass StorageClass = VarDecl::None; 2905 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2906 StorageClass = VarDecl::Register; 2907 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2908 Diag(DS.getStorageClassSpecLoc(), 2909 diag::err_invalid_storage_class_in_func_decl); 2910 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2911 } 2912 2913 if (D.getDeclSpec().isThreadSpecified()) 2914 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2915 2916 DiagnoseFunctionSpecifiers(D); 2917 2918 // Check that there are no default arguments inside the type of this 2919 // parameter (C++ only). 2920 if (getLangOptions().CPlusPlus) 2921 CheckExtraCXXDefaultArguments(D); 2922 2923 TagDecl *OwnedDecl = 0; 2924 QualType parmDeclType = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedDecl); 2925 2926 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 2927 // C++ [dcl.fct]p6: 2928 // Types shall not be defined in return or parameter types. 2929 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 2930 << Context.getTypeDeclType(OwnedDecl); 2931 } 2932 2933 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2934 // Can this happen for params? We already checked that they don't conflict 2935 // among each other. Here they can only shadow globals, which is ok. 2936 IdentifierInfo *II = D.getIdentifier(); 2937 if (II) { 2938 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2939 if (PrevDecl->isTemplateParameter()) { 2940 // Maybe we will complain about the shadowed template parameter. 2941 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2942 // Just pretend that we didn't see the previous declaration. 2943 PrevDecl = 0; 2944 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2945 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2946 2947 // Recover by removing the name 2948 II = 0; 2949 D.SetIdentifier(0, D.getIdentifierLoc()); 2950 } 2951 } 2952 } 2953 2954 // Parameters can not be abstract class types. 2955 // For record types, this is done by the AbstractClassUsageDiagnoser once 2956 // the class has been completely parsed. 2957 if (!CurContext->isRecord() && 2958 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2959 diag::err_abstract_type_in_decl, 2960 AbstractParamType)) 2961 D.setInvalidType(true); 2962 2963 QualType T = adjustParameterType(parmDeclType); 2964 2965 ParmVarDecl *New; 2966 if (T == parmDeclType) // parameter type did not need adjustment 2967 New = ParmVarDecl::Create(Context, CurContext, 2968 D.getIdentifierLoc(), II, 2969 parmDeclType, StorageClass, 2970 0); 2971 else // keep track of both the adjusted and unadjusted types 2972 New = OriginalParmVarDecl::Create(Context, CurContext, 2973 D.getIdentifierLoc(), II, T, 2974 parmDeclType, StorageClass, 0); 2975 2976 if (D.isInvalidType()) 2977 New->setInvalidDecl(); 2978 2979 // Parameter declarators cannot be interface types. All ObjC objects are 2980 // passed by reference. 2981 if (T->isObjCInterfaceType()) { 2982 Diag(D.getIdentifierLoc(), 2983 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2984 New->setInvalidDecl(); 2985 } 2986 2987 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2988 if (D.getCXXScopeSpec().isSet()) { 2989 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2990 << D.getCXXScopeSpec().getRange(); 2991 New->setInvalidDecl(); 2992 } 2993 2994 // Add the parameter declaration into this scope. 2995 S->AddDecl(DeclPtrTy::make(New)); 2996 if (II) 2997 IdResolver.AddDecl(New); 2998 2999 ProcessDeclAttributes(S, New, D); 3000 3001 if (New->hasAttr<BlocksAttr>(Context)) { 3002 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3003 } 3004 return DeclPtrTy::make(New); 3005} 3006 3007void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3008 SourceLocation LocAfterDecls) { 3009 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3010 "Not a function declarator!"); 3011 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3012 3013 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3014 // for a K&R function. 3015 if (!FTI.hasPrototype) { 3016 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3017 --i; 3018 if (FTI.ArgInfo[i].Param == 0) { 3019 std::string Code = " int "; 3020 Code += FTI.ArgInfo[i].Ident->getName(); 3021 Code += ";\n"; 3022 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3023 << FTI.ArgInfo[i].Ident 3024 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3025 3026 // Implicitly declare the argument as type 'int' for lack of a better 3027 // type. 3028 DeclSpec DS; 3029 const char* PrevSpec; // unused 3030 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3031 PrevSpec); 3032 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3033 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3034 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3035 } 3036 } 3037 } 3038} 3039 3040Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3041 Declarator &D) { 3042 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3043 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3044 "Not a function declarator!"); 3045 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3046 3047 if (FTI.hasPrototype) { 3048 // FIXME: Diagnose arguments without names in C. 3049 } 3050 3051 Scope *ParentScope = FnBodyScope->getParent(); 3052 3053 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3054 MultiTemplateParamsArg(*this), 3055 /*IsFunctionDefinition=*/true); 3056 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3057} 3058 3059Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3060 if (!D) 3061 return D; 3062 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 3063 3064 CurFunctionNeedsScopeChecking = false; 3065 3066 // See if this is a redefinition. 3067 const FunctionDecl *Definition; 3068 if (FD->getBody(Context, Definition)) { 3069 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3070 Diag(Definition->getLocation(), diag::note_previous_definition); 3071 } 3072 3073 // Builtin functions cannot be defined. 3074 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3075 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3076 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3077 FD->setInvalidDecl(); 3078 } 3079 } 3080 3081 // The return type of a function definition must be complete 3082 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3083 QualType ResultType = FD->getResultType(); 3084 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3085 !FD->isInvalidDecl() && 3086 RequireCompleteType(FD->getLocation(), ResultType, 3087 diag::err_func_def_incomplete_result)) 3088 FD->setInvalidDecl(); 3089 3090 // GNU warning -Wmissing-prototypes: 3091 // Warn if a global function is defined without a previous 3092 // prototype declaration. This warning is issued even if the 3093 // definition itself provides a prototype. The aim is to detect 3094 // global functions that fail to be declared in header files. 3095 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3096 !FD->isMain()) { 3097 bool MissingPrototype = true; 3098 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3099 Prev; Prev = Prev->getPreviousDeclaration()) { 3100 // Ignore any declarations that occur in function or method 3101 // scope, because they aren't visible from the header. 3102 if (Prev->getDeclContext()->isFunctionOrMethod()) 3103 continue; 3104 3105 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3106 break; 3107 } 3108 3109 if (MissingPrototype) 3110 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3111 } 3112 3113 if (FnBodyScope) 3114 PushDeclContext(FnBodyScope, FD); 3115 3116 // Check the validity of our function parameters 3117 CheckParmsForFunctionDef(FD); 3118 3119 // Introduce our parameters into the function scope 3120 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3121 ParmVarDecl *Param = FD->getParamDecl(p); 3122 Param->setOwningFunction(FD); 3123 3124 // If this has an identifier, add it to the scope stack. 3125 if (Param->getIdentifier() && FnBodyScope) 3126 PushOnScopeChains(Param, FnBodyScope); 3127 } 3128 3129 // Checking attributes of current function definition 3130 // dllimport attribute. 3131 if (FD->getAttr<DLLImportAttr>(Context) && 3132 (!FD->getAttr<DLLExportAttr>(Context))) { 3133 // dllimport attribute cannot be applied to definition. 3134 if (!(FD->getAttr<DLLImportAttr>(Context))->isInherited()) { 3135 Diag(FD->getLocation(), 3136 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3137 << "dllimport"; 3138 FD->setInvalidDecl(); 3139 return DeclPtrTy::make(FD); 3140 } else { 3141 // If a symbol previously declared dllimport is later defined, the 3142 // attribute is ignored in subsequent references, and a warning is 3143 // emitted. 3144 Diag(FD->getLocation(), 3145 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3146 << FD->getNameAsCString() << "dllimport"; 3147 } 3148 } 3149 return DeclPtrTy::make(FD); 3150} 3151 3152Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3153 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3154} 3155 3156Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3157 bool IsInstantiation) { 3158 Decl *dcl = D.getAs<Decl>(); 3159 Stmt *Body = BodyArg.takeAs<Stmt>(); 3160 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3161 FD->setBody(Body); 3162 3163 if (!FD->isInvalidDecl()) 3164 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3165 3166 // C++ [basic.def.odr]p2: 3167 // [...] A virtual member function is used if it is not pure. [...] 3168 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3169 if (Method->isVirtual() && !Method->isPure()) 3170 MarkDeclarationReferenced(Method->getLocation(), Method); 3171 3172 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3173 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3174 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3175 MD->setBody(Body); 3176 3177 if (!MD->isInvalidDecl()) 3178 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3179 } else { 3180 Body->Destroy(Context); 3181 return DeclPtrTy(); 3182 } 3183 if (!IsInstantiation) 3184 PopDeclContext(); 3185 3186 // Verify and clean out per-function state. 3187 3188 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3189 3190 // Check goto/label use. 3191 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3192 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3193 LabelStmt *L = I->second; 3194 3195 // Verify that we have no forward references left. If so, there was a goto 3196 // or address of a label taken, but no definition of it. Label fwd 3197 // definitions are indicated with a null substmt. 3198 if (L->getSubStmt() != 0) 3199 continue; 3200 3201 // Emit error. 3202 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3203 3204 // At this point, we have gotos that use the bogus label. Stitch it into 3205 // the function body so that they aren't leaked and that the AST is well 3206 // formed. 3207 if (Body == 0) { 3208 // The whole function wasn't parsed correctly, just delete this. 3209 L->Destroy(Context); 3210 continue; 3211 } 3212 3213 // Otherwise, the body is valid: we want to stitch the label decl into the 3214 // function somewhere so that it is properly owned and so that the goto 3215 // has a valid target. Do this by creating a new compound stmt with the 3216 // label in it. 3217 3218 // Give the label a sub-statement. 3219 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3220 3221 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3222 cast<CXXTryStmt>(Body)->getTryBlock() : 3223 cast<CompoundStmt>(Body); 3224 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3225 Elements.push_back(L); 3226 Compound->setStmts(Context, &Elements[0], Elements.size()); 3227 } 3228 FunctionLabelMap.clear(); 3229 3230 if (!Body) return D; 3231 3232 // Verify that that gotos and switch cases don't jump into scopes illegally. 3233 if (CurFunctionNeedsScopeChecking) 3234 DiagnoseInvalidJumps(Body); 3235 3236 // C++ constructors that have function-try-blocks can't have return statements 3237 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3238 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3239 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3240 3241 return D; 3242} 3243 3244/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3245/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3246NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3247 IdentifierInfo &II, Scope *S) { 3248 // Before we produce a declaration for an implicitly defined 3249 // function, see whether there was a locally-scoped declaration of 3250 // this name as a function or variable. If so, use that 3251 // (non-visible) declaration, and complain about it. 3252 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3253 = LocallyScopedExternalDecls.find(&II); 3254 if (Pos != LocallyScopedExternalDecls.end()) { 3255 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3256 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3257 return Pos->second; 3258 } 3259 3260 // Extension in C99. Legal in C90, but warn about it. 3261 if (getLangOptions().C99) 3262 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3263 else 3264 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3265 3266 // FIXME: handle stuff like: 3267 // void foo() { extern float X(); } 3268 // void bar() { X(); } <-- implicit decl for X in another scope. 3269 3270 // Set a Declarator for the implicit definition: int foo(); 3271 const char *Dummy; 3272 DeclSpec DS; 3273 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3274 Error = Error; // Silence warning. 3275 assert(!Error && "Error setting up implicit decl!"); 3276 Declarator D(DS, Declarator::BlockContext); 3277 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3278 0, 0, false, SourceLocation(), 3279 false, 0,0,0, Loc, D), 3280 SourceLocation()); 3281 D.SetIdentifier(&II, Loc); 3282 3283 // Insert this function into translation-unit scope. 3284 3285 DeclContext *PrevDC = CurContext; 3286 CurContext = Context.getTranslationUnitDecl(); 3287 3288 FunctionDecl *FD = 3289 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3290 FD->setImplicit(); 3291 3292 CurContext = PrevDC; 3293 3294 AddKnownFunctionAttributes(FD); 3295 3296 return FD; 3297} 3298 3299/// \brief Adds any function attributes that we know a priori based on 3300/// the declaration of this function. 3301/// 3302/// These attributes can apply both to implicitly-declared builtins 3303/// (like __builtin___printf_chk) or to library-declared functions 3304/// like NSLog or printf. 3305void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3306 if (FD->isInvalidDecl()) 3307 return; 3308 3309 // If this is a built-in function, map its builtin attributes to 3310 // actual attributes. 3311 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3312 // Handle printf-formatting attributes. 3313 unsigned FormatIdx; 3314 bool HasVAListArg; 3315 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3316 if (!FD->getAttr<FormatAttr>(Context)) 3317 FD->addAttr(Context, 3318 ::new (Context) FormatAttr("printf", FormatIdx + 1, 3319 HasVAListArg ? 0 : FormatIdx + 2)); 3320 } 3321 3322 // Mark const if we don't care about errno and that is the only 3323 // thing preventing the function from being const. This allows 3324 // IRgen to use LLVM intrinsics for such functions. 3325 if (!getLangOptions().MathErrno && 3326 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3327 if (!FD->getAttr<ConstAttr>(Context)) 3328 FD->addAttr(Context, ::new (Context) ConstAttr()); 3329 } 3330 } 3331 3332 IdentifierInfo *Name = FD->getIdentifier(); 3333 if (!Name) 3334 return; 3335 if ((!getLangOptions().CPlusPlus && 3336 FD->getDeclContext()->isTranslationUnit()) || 3337 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3338 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3339 LinkageSpecDecl::lang_c)) { 3340 // Okay: this could be a libc/libm/Objective-C function we know 3341 // about. 3342 } else 3343 return; 3344 3345 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3346 if (const FormatAttr *Format = FD->getAttr<FormatAttr>(Context)) { 3347 // FIXME: We known better than our headers. 3348 const_cast<FormatAttr *>(Format)->setType("printf"); 3349 } else 3350 FD->addAttr(Context, 3351 ::new (Context) FormatAttr("printf", 1, 3352 Name->isStr("NSLogv") ? 0 : 2)); 3353 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3354 if (!FD->getAttr<FormatAttr>(Context)) 3355 FD->addAttr(Context, 3356 ::new (Context) FormatAttr("printf", 2, 3357 Name->isStr("vasprintf") ? 0 : 3)); 3358 } 3359} 3360 3361TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3362 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3363 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3364 3365 // Scope manipulation handled by caller. 3366 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3367 D.getIdentifierLoc(), 3368 D.getIdentifier(), 3369 T); 3370 3371 if (TagType *TT = dyn_cast<TagType>(T)) { 3372 TagDecl *TD = TT->getDecl(); 3373 3374 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3375 // keep track of the TypedefDecl. 3376 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3377 TD->setTypedefForAnonDecl(NewTD); 3378 } 3379 3380 if (D.isInvalidType()) 3381 NewTD->setInvalidDecl(); 3382 return NewTD; 3383} 3384 3385 3386/// \brief Determine whether a tag with a given kind is acceptable 3387/// as a redeclaration of the given tag declaration. 3388/// 3389/// \returns true if the new tag kind is acceptable, false otherwise. 3390bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3391 TagDecl::TagKind NewTag, 3392 SourceLocation NewTagLoc, 3393 const IdentifierInfo &Name) { 3394 // C++ [dcl.type.elab]p3: 3395 // The class-key or enum keyword present in the 3396 // elaborated-type-specifier shall agree in kind with the 3397 // declaration to which the name in theelaborated-type-specifier 3398 // refers. This rule also applies to the form of 3399 // elaborated-type-specifier that declares a class-name or 3400 // friend class since it can be construed as referring to the 3401 // definition of the class. Thus, in any 3402 // elaborated-type-specifier, the enum keyword shall be used to 3403 // refer to an enumeration (7.2), the union class-keyshall be 3404 // used to refer to a union (clause 9), and either the class or 3405 // struct class-key shall be used to refer to a class (clause 9) 3406 // declared using the class or struct class-key. 3407 TagDecl::TagKind OldTag = Previous->getTagKind(); 3408 if (OldTag == NewTag) 3409 return true; 3410 3411 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3412 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3413 // Warn about the struct/class tag mismatch. 3414 bool isTemplate = false; 3415 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3416 isTemplate = Record->getDescribedClassTemplate(); 3417 3418 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3419 << (NewTag == TagDecl::TK_class) 3420 << isTemplate << &Name 3421 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3422 OldTag == TagDecl::TK_class? "class" : "struct"); 3423 Diag(Previous->getLocation(), diag::note_previous_use); 3424 return true; 3425 } 3426 return false; 3427} 3428 3429/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3430/// former case, Name will be non-null. In the later case, Name will be null. 3431/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3432/// reference/declaration/definition of a tag. 3433Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3434 SourceLocation KWLoc, const CXXScopeSpec &SS, 3435 IdentifierInfo *Name, SourceLocation NameLoc, 3436 AttributeList *Attr, AccessSpecifier AS, 3437 bool &OwnedDecl) { 3438 // If this is not a definition, it must have a name. 3439 assert((Name != 0 || TK == TK_Definition) && 3440 "Nameless record must be a definition!"); 3441 3442 OwnedDecl = false; 3443 TagDecl::TagKind Kind; 3444 switch (TagSpec) { 3445 default: assert(0 && "Unknown tag type!"); 3446 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3447 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3448 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3449 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3450 } 3451 3452 DeclContext *SearchDC = CurContext; 3453 DeclContext *DC = CurContext; 3454 NamedDecl *PrevDecl = 0; 3455 3456 bool Invalid = false; 3457 3458 if (Name && SS.isNotEmpty()) { 3459 // We have a nested-name tag ('struct foo::bar'). 3460 3461 // Check for invalid 'foo::'. 3462 if (SS.isInvalid()) { 3463 Name = 0; 3464 goto CreateNewDecl; 3465 } 3466 3467 if (RequireCompleteDeclContext(SS)) 3468 return DeclPtrTy::make((Decl *)0); 3469 3470 DC = computeDeclContext(SS); 3471 SearchDC = DC; 3472 // Look-up name inside 'foo::'. 3473 PrevDecl 3474 = dyn_cast_or_null<TagDecl>( 3475 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3476 3477 // A tag 'foo::bar' must already exist. 3478 if (PrevDecl == 0) { 3479 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3480 Name = 0; 3481 Invalid = true; 3482 goto CreateNewDecl; 3483 } 3484 } else if (Name) { 3485 // If this is a named struct, check to see if there was a previous forward 3486 // declaration or definition. 3487 // FIXME: We're looking into outer scopes here, even when we 3488 // shouldn't be. Doing so can result in ambiguities that we 3489 // shouldn't be diagnosing. 3490 LookupResult R = LookupName(S, Name, LookupTagName, 3491 /*RedeclarationOnly=*/(TK != TK_Reference)); 3492 if (R.isAmbiguous()) { 3493 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3494 // FIXME: This is not best way to recover from case like: 3495 // 3496 // struct S s; 3497 // 3498 // causes needless "incomplete type" error later. 3499 Name = 0; 3500 PrevDecl = 0; 3501 Invalid = true; 3502 } 3503 else 3504 PrevDecl = R; 3505 3506 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3507 // FIXME: This makes sure that we ignore the contexts associated 3508 // with C structs, unions, and enums when looking for a matching 3509 // tag declaration or definition. See the similar lookup tweak 3510 // in Sema::LookupName; is there a better way to deal with this? 3511 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3512 SearchDC = SearchDC->getParent(); 3513 } 3514 } 3515 3516 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3517 // Maybe we will complain about the shadowed template parameter. 3518 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3519 // Just pretend that we didn't see the previous declaration. 3520 PrevDecl = 0; 3521 } 3522 3523 if (PrevDecl) { 3524 // Check whether the previous declaration is usable. 3525 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3526 3527 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3528 // If this is a use of a previous tag, or if the tag is already declared 3529 // in the same scope (so that the definition/declaration completes or 3530 // rementions the tag), reuse the decl. 3531 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3532 // Make sure that this wasn't declared as an enum and now used as a 3533 // struct or something similar. 3534 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3535 bool SafeToContinue 3536 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3537 Kind != TagDecl::TK_enum); 3538 if (SafeToContinue) 3539 Diag(KWLoc, diag::err_use_with_wrong_tag) 3540 << Name 3541 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3542 PrevTagDecl->getKindName()); 3543 else 3544 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3545 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3546 3547 if (SafeToContinue) 3548 Kind = PrevTagDecl->getTagKind(); 3549 else { 3550 // Recover by making this an anonymous redefinition. 3551 Name = 0; 3552 PrevDecl = 0; 3553 Invalid = true; 3554 } 3555 } 3556 3557 if (!Invalid) { 3558 // If this is a use, just return the declaration we found. 3559 3560 // FIXME: In the future, return a variant or some other clue 3561 // for the consumer of this Decl to know it doesn't own it. 3562 // For our current ASTs this shouldn't be a problem, but will 3563 // need to be changed with DeclGroups. 3564 if (TK == TK_Reference) 3565 return DeclPtrTy::make(PrevDecl); 3566 3567 // Diagnose attempts to redefine a tag. 3568 if (TK == TK_Definition) { 3569 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3570 Diag(NameLoc, diag::err_redefinition) << Name; 3571 Diag(Def->getLocation(), diag::note_previous_definition); 3572 // If this is a redefinition, recover by making this 3573 // struct be anonymous, which will make any later 3574 // references get the previous definition. 3575 Name = 0; 3576 PrevDecl = 0; 3577 Invalid = true; 3578 } else { 3579 // If the type is currently being defined, complain 3580 // about a nested redefinition. 3581 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3582 if (Tag->isBeingDefined()) { 3583 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3584 Diag(PrevTagDecl->getLocation(), 3585 diag::note_previous_definition); 3586 Name = 0; 3587 PrevDecl = 0; 3588 Invalid = true; 3589 } 3590 } 3591 3592 // Okay, this is definition of a previously declared or referenced 3593 // tag PrevDecl. We're going to create a new Decl for it. 3594 } 3595 } 3596 // If we get here we have (another) forward declaration or we 3597 // have a definition. Just create a new decl. 3598 } else { 3599 // If we get here, this is a definition of a new tag type in a nested 3600 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3601 // new decl/type. We set PrevDecl to NULL so that the entities 3602 // have distinct types. 3603 PrevDecl = 0; 3604 } 3605 // If we get here, we're going to create a new Decl. If PrevDecl 3606 // is non-NULL, it's a definition of the tag declared by 3607 // PrevDecl. If it's NULL, we have a new definition. 3608 } else { 3609 // PrevDecl is a namespace, template, or anything else 3610 // that lives in the IDNS_Tag identifier namespace. 3611 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3612 // The tag name clashes with a namespace name, issue an error and 3613 // recover by making this tag be anonymous. 3614 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3615 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3616 Name = 0; 3617 PrevDecl = 0; 3618 Invalid = true; 3619 } else { 3620 // The existing declaration isn't relevant to us; we're in a 3621 // new scope, so clear out the previous declaration. 3622 PrevDecl = 0; 3623 } 3624 } 3625 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3626 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3627 // C++ [basic.scope.pdecl]p5: 3628 // -- for an elaborated-type-specifier of the form 3629 // 3630 // class-key identifier 3631 // 3632 // if the elaborated-type-specifier is used in the 3633 // decl-specifier-seq or parameter-declaration-clause of a 3634 // function defined in namespace scope, the identifier is 3635 // declared as a class-name in the namespace that contains 3636 // the declaration; otherwise, except as a friend 3637 // declaration, the identifier is declared in the smallest 3638 // non-class, non-function-prototype scope that contains the 3639 // declaration. 3640 // 3641 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3642 // C structs and unions. 3643 // 3644 // GNU C also supports this behavior as part of its incomplete 3645 // enum types extension, while GNU C++ does not. 3646 // 3647 // Find the context where we'll be declaring the tag. 3648 // FIXME: We would like to maintain the current DeclContext as the 3649 // lexical context, 3650 while (SearchDC->isRecord()) 3651 SearchDC = SearchDC->getParent(); 3652 3653 // Find the scope where we'll be declaring the tag. 3654 while (S->isClassScope() || 3655 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3656 ((S->getFlags() & Scope::DeclScope) == 0) || 3657 (S->getEntity() && 3658 ((DeclContext *)S->getEntity())->isTransparentContext())) 3659 S = S->getParent(); 3660 } 3661 3662CreateNewDecl: 3663 3664 // If there is an identifier, use the location of the identifier as the 3665 // location of the decl, otherwise use the location of the struct/union 3666 // keyword. 3667 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3668 3669 // Otherwise, create a new declaration. If there is a previous 3670 // declaration of the same entity, the two will be linked via 3671 // PrevDecl. 3672 TagDecl *New; 3673 3674 if (Kind == TagDecl::TK_enum) { 3675 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3676 // enum X { A, B, C } D; D should chain to X. 3677 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3678 cast_or_null<EnumDecl>(PrevDecl)); 3679 // If this is an undefined enum, warn. 3680 if (TK != TK_Definition && !Invalid) { 3681 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3682 : diag::ext_forward_ref_enum; 3683 Diag(Loc, DK); 3684 } 3685 } else { 3686 // struct/union/class 3687 3688 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3689 // struct X { int A; } D; D should chain to X. 3690 if (getLangOptions().CPlusPlus) 3691 // FIXME: Look for a way to use RecordDecl for simple structs. 3692 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3693 cast_or_null<CXXRecordDecl>(PrevDecl)); 3694 else 3695 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3696 cast_or_null<RecordDecl>(PrevDecl)); 3697 } 3698 3699 if (Kind != TagDecl::TK_enum) { 3700 // Handle #pragma pack: if the #pragma pack stack has non-default 3701 // alignment, make up a packed attribute for this decl. These 3702 // attributes are checked when the ASTContext lays out the 3703 // structure. 3704 // 3705 // It is important for implementing the correct semantics that this 3706 // happen here (in act on tag decl). The #pragma pack stack is 3707 // maintained as a result of parser callbacks which can occur at 3708 // many points during the parsing of a struct declaration (because 3709 // the #pragma tokens are effectively skipped over during the 3710 // parsing of the struct). 3711 if (unsigned Alignment = getPragmaPackAlignment()) 3712 New->addAttr(Context, ::new (Context) PackedAttr(Alignment * 8)); 3713 } 3714 3715 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3716 // C++ [dcl.typedef]p3: 3717 // [...] Similarly, in a given scope, a class or enumeration 3718 // shall not be declared with the same name as a typedef-name 3719 // that is declared in that scope and refers to a type other 3720 // than the class or enumeration itself. 3721 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3722 TypedefDecl *PrevTypedef = 0; 3723 if (Lookup.getKind() == LookupResult::Found) 3724 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3725 3726 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3727 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3728 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3729 Diag(Loc, diag::err_tag_definition_of_typedef) 3730 << Context.getTypeDeclType(New) 3731 << PrevTypedef->getUnderlyingType(); 3732 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3733 Invalid = true; 3734 } 3735 } 3736 3737 if (Invalid) 3738 New->setInvalidDecl(); 3739 3740 if (Attr) 3741 ProcessDeclAttributeList(S, New, Attr); 3742 3743 // If we're declaring or defining a tag in function prototype scope 3744 // in C, note that this type can only be used within the function. 3745 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3746 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3747 3748 // Set the lexical context. If the tag has a C++ scope specifier, the 3749 // lexical context will be different from the semantic context. 3750 New->setLexicalDeclContext(CurContext); 3751 3752 // Set the access specifier. 3753 if (!Invalid) 3754 SetMemberAccessSpecifier(New, PrevDecl, AS); 3755 3756 if (TK == TK_Definition) 3757 New->startDefinition(); 3758 3759 // If this has an identifier, add it to the scope stack. 3760 if (Name) { 3761 S = getNonFieldDeclScope(S); 3762 PushOnScopeChains(New, S); 3763 } else { 3764 CurContext->addDecl(Context, New); 3765 } 3766 3767 OwnedDecl = true; 3768 return DeclPtrTy::make(New); 3769} 3770 3771void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3772 AdjustDeclIfTemplate(TagD); 3773 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3774 3775 // Enter the tag context. 3776 PushDeclContext(S, Tag); 3777 3778 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3779 FieldCollector->StartClass(); 3780 3781 if (Record->getIdentifier()) { 3782 // C++ [class]p2: 3783 // [...] The class-name is also inserted into the scope of the 3784 // class itself; this is known as the injected-class-name. For 3785 // purposes of access checking, the injected-class-name is treated 3786 // as if it were a public member name. 3787 CXXRecordDecl *InjectedClassName 3788 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3789 CurContext, Record->getLocation(), 3790 Record->getIdentifier(), Record); 3791 InjectedClassName->setImplicit(); 3792 InjectedClassName->setAccess(AS_public); 3793 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3794 InjectedClassName->setDescribedClassTemplate(Template); 3795 PushOnScopeChains(InjectedClassName, S); 3796 assert(InjectedClassName->isInjectedClassName() && 3797 "Broken injected-class-name"); 3798 } 3799 } 3800} 3801 3802void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3803 AdjustDeclIfTemplate(TagD); 3804 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3805 3806 if (isa<CXXRecordDecl>(Tag)) 3807 FieldCollector->FinishClass(); 3808 3809 // Exit this scope of this tag's definition. 3810 PopDeclContext(); 3811 3812 // Notify the consumer that we've defined a tag. 3813 Consumer.HandleTagDeclDefinition(Tag); 3814} 3815 3816// Note that FieldName may be null for anonymous bitfields. 3817bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3818 QualType FieldTy, const Expr *BitWidth) { 3819 3820 // C99 6.7.2.1p4 - verify the field type. 3821 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3822 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3823 // Handle incomplete types with specific error. 3824 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3825 return true; 3826 if (FieldName) 3827 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3828 << FieldName << FieldTy << BitWidth->getSourceRange(); 3829 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3830 << FieldTy << BitWidth->getSourceRange(); 3831 } 3832 3833 // If the bit-width is type- or value-dependent, don't try to check 3834 // it now. 3835 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3836 return false; 3837 3838 llvm::APSInt Value; 3839 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3840 return true; 3841 3842 // Zero-width bitfield is ok for anonymous field. 3843 if (Value == 0 && FieldName) 3844 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3845 3846 if (Value.isSigned() && Value.isNegative()) { 3847 if (FieldName) 3848 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3849 << FieldName << Value.toString(10); 3850 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3851 << Value.toString(10); 3852 } 3853 3854 if (!FieldTy->isDependentType()) { 3855 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3856 if (Value.getZExtValue() > TypeSize) { 3857 if (FieldName) 3858 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3859 << FieldName << (unsigned)TypeSize; 3860 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3861 << (unsigned)TypeSize; 3862 } 3863 } 3864 3865 return false; 3866} 3867 3868/// ActOnField - Each field of a struct/union/class is passed into this in order 3869/// to create a FieldDecl object for it. 3870Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3871 SourceLocation DeclStart, 3872 Declarator &D, ExprTy *BitfieldWidth) { 3873 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3874 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3875 AS_public); 3876 return DeclPtrTy::make(Res); 3877} 3878 3879/// HandleField - Analyze a field of a C struct or a C++ data member. 3880/// 3881FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3882 SourceLocation DeclStart, 3883 Declarator &D, Expr *BitWidth, 3884 AccessSpecifier AS) { 3885 IdentifierInfo *II = D.getIdentifier(); 3886 SourceLocation Loc = DeclStart; 3887 if (II) Loc = D.getIdentifierLoc(); 3888 3889 QualType T = GetTypeForDeclarator(D, S); 3890 if (getLangOptions().CPlusPlus) 3891 CheckExtraCXXDefaultArguments(D); 3892 3893 DiagnoseFunctionSpecifiers(D); 3894 3895 if (D.getDeclSpec().isThreadSpecified()) 3896 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3897 3898 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3899 3900 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3901 // Maybe we will complain about the shadowed template parameter. 3902 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3903 // Just pretend that we didn't see the previous declaration. 3904 PrevDecl = 0; 3905 } 3906 3907 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3908 PrevDecl = 0; 3909 3910 FieldDecl *NewFD 3911 = CheckFieldDecl(II, T, Record, Loc, 3912 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3913 BitWidth, AS, PrevDecl, &D); 3914 if (NewFD->isInvalidDecl() && PrevDecl) { 3915 // Don't introduce NewFD into scope; there's already something 3916 // with the same name in the same scope. 3917 } else if (II) { 3918 PushOnScopeChains(NewFD, S); 3919 } else 3920 Record->addDecl(Context, NewFD); 3921 3922 return NewFD; 3923} 3924 3925/// \brief Build a new FieldDecl and check its well-formedness. 3926/// 3927/// This routine builds a new FieldDecl given the fields name, type, 3928/// record, etc. \p PrevDecl should refer to any previous declaration 3929/// with the same name and in the same scope as the field to be 3930/// created. 3931/// 3932/// \returns a new FieldDecl. 3933/// 3934/// \todo The Declarator argument is a hack. It will be removed once 3935FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3936 RecordDecl *Record, SourceLocation Loc, 3937 bool Mutable, Expr *BitWidth, 3938 AccessSpecifier AS, NamedDecl *PrevDecl, 3939 Declarator *D) { 3940 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3941 bool InvalidDecl = false; 3942 if (D) InvalidDecl = D->isInvalidType(); 3943 3944 // If we receive a broken type, recover by assuming 'int' and 3945 // marking this declaration as invalid. 3946 if (T.isNull()) { 3947 InvalidDecl = true; 3948 T = Context.IntTy; 3949 } 3950 3951 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3952 // than a variably modified type. 3953 if (T->isVariablyModifiedType()) { 3954 bool SizeIsNegative; 3955 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3956 SizeIsNegative); 3957 if (!FixedTy.isNull()) { 3958 Diag(Loc, diag::warn_illegal_constant_array_size); 3959 T = FixedTy; 3960 } else { 3961 if (SizeIsNegative) 3962 Diag(Loc, diag::err_typecheck_negative_array_size); 3963 else 3964 Diag(Loc, diag::err_typecheck_field_variable_size); 3965 T = Context.IntTy; 3966 InvalidDecl = true; 3967 } 3968 } 3969 3970 // Fields can not have abstract class types 3971 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3972 AbstractFieldType)) 3973 InvalidDecl = true; 3974 3975 // If this is declared as a bit-field, check the bit-field. 3976 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3977 InvalidDecl = true; 3978 DeleteExpr(BitWidth); 3979 BitWidth = 0; 3980 } 3981 3982 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3983 Mutable); 3984 if (InvalidDecl) 3985 NewFD->setInvalidDecl(); 3986 3987 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3988 Diag(Loc, diag::err_duplicate_member) << II; 3989 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3990 NewFD->setInvalidDecl(); 3991 } 3992 3993 if (getLangOptions().CPlusPlus && !T->isPODType()) 3994 cast<CXXRecordDecl>(Record)->setPOD(false); 3995 3996 // FIXME: We need to pass in the attributes given an AST 3997 // representation, not a parser representation. 3998 if (D) 3999 // FIXME: What to pass instead of TUScope? 4000 ProcessDeclAttributes(TUScope, NewFD, *D); 4001 4002 if (T.isObjCGCWeak()) 4003 Diag(Loc, diag::warn_attribute_weak_on_field); 4004 4005 NewFD->setAccess(AS); 4006 4007 // C++ [dcl.init.aggr]p1: 4008 // An aggregate is an array or a class (clause 9) with [...] no 4009 // private or protected non-static data members (clause 11). 4010 // A POD must be an aggregate. 4011 if (getLangOptions().CPlusPlus && 4012 (AS == AS_private || AS == AS_protected)) { 4013 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4014 CXXRecord->setAggregate(false); 4015 CXXRecord->setPOD(false); 4016 } 4017 4018 return NewFD; 4019} 4020 4021/// TranslateIvarVisibility - Translate visibility from a token ID to an 4022/// AST enum value. 4023static ObjCIvarDecl::AccessControl 4024TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4025 switch (ivarVisibility) { 4026 default: assert(0 && "Unknown visitibility kind"); 4027 case tok::objc_private: return ObjCIvarDecl::Private; 4028 case tok::objc_public: return ObjCIvarDecl::Public; 4029 case tok::objc_protected: return ObjCIvarDecl::Protected; 4030 case tok::objc_package: return ObjCIvarDecl::Package; 4031 } 4032} 4033 4034/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4035/// in order to create an IvarDecl object for it. 4036Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4037 SourceLocation DeclStart, 4038 DeclPtrTy IntfDecl, 4039 Declarator &D, ExprTy *BitfieldWidth, 4040 tok::ObjCKeywordKind Visibility) { 4041 4042 IdentifierInfo *II = D.getIdentifier(); 4043 Expr *BitWidth = (Expr*)BitfieldWidth; 4044 SourceLocation Loc = DeclStart; 4045 if (II) Loc = D.getIdentifierLoc(); 4046 4047 // FIXME: Unnamed fields can be handled in various different ways, for 4048 // example, unnamed unions inject all members into the struct namespace! 4049 4050 QualType T = GetTypeForDeclarator(D, S); 4051 4052 if (BitWidth) { 4053 // 6.7.2.1p3, 6.7.2.1p4 4054 if (VerifyBitField(Loc, II, T, BitWidth)) { 4055 D.setInvalidType(); 4056 DeleteExpr(BitWidth); 4057 BitWidth = 0; 4058 } 4059 } else { 4060 // Not a bitfield. 4061 4062 // validate II. 4063 4064 } 4065 4066 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4067 // than a variably modified type. 4068 if (T->isVariablyModifiedType()) { 4069 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4070 D.setInvalidType(); 4071 } 4072 4073 // Get the visibility (access control) for this ivar. 4074 ObjCIvarDecl::AccessControl ac = 4075 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4076 : ObjCIvarDecl::None; 4077 // Must set ivar's DeclContext to its enclosing interface. 4078 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4079 DeclContext *EnclosingContext; 4080 if (ObjCImplementationDecl *IMPDecl = 4081 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4082 // Case of ivar declared in an implementation. Context is that of its class. 4083 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4084 assert(IDecl && "No class- ActOnIvar"); 4085 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4086 } 4087 else 4088 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4089 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4090 4091 // Construct the decl. 4092 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4093 EnclosingContext, Loc, II, T,ac, 4094 (Expr *)BitfieldWidth); 4095 4096 if (II) { 4097 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4098 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4099 && !isa<TagDecl>(PrevDecl)) { 4100 Diag(Loc, diag::err_duplicate_member) << II; 4101 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4102 NewID->setInvalidDecl(); 4103 } 4104 } 4105 4106 // Process attributes attached to the ivar. 4107 ProcessDeclAttributes(S, NewID, D); 4108 4109 if (D.isInvalidType()) 4110 NewID->setInvalidDecl(); 4111 4112 if (II) { 4113 // FIXME: When interfaces are DeclContexts, we'll need to add 4114 // these to the interface. 4115 S->AddDecl(DeclPtrTy::make(NewID)); 4116 IdResolver.AddDecl(NewID); 4117 } 4118 4119 return DeclPtrTy::make(NewID); 4120} 4121 4122void Sema::ActOnFields(Scope* S, 4123 SourceLocation RecLoc, DeclPtrTy RecDecl, 4124 DeclPtrTy *Fields, unsigned NumFields, 4125 SourceLocation LBrac, SourceLocation RBrac, 4126 AttributeList *Attr) { 4127 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4128 assert(EnclosingDecl && "missing record or interface decl"); 4129 4130 // If the decl this is being inserted into is invalid, then it may be a 4131 // redeclaration or some other bogus case. Don't try to add fields to it. 4132 if (EnclosingDecl->isInvalidDecl()) { 4133 // FIXME: Deallocate fields? 4134 return; 4135 } 4136 4137 4138 // Verify that all the fields are okay. 4139 unsigned NumNamedMembers = 0; 4140 llvm::SmallVector<FieldDecl*, 32> RecFields; 4141 4142 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4143 for (unsigned i = 0; i != NumFields; ++i) { 4144 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4145 4146 // Get the type for the field. 4147 Type *FDTy = FD->getType().getTypePtr(); 4148 4149 if (!FD->isAnonymousStructOrUnion()) { 4150 // Remember all fields written by the user. 4151 RecFields.push_back(FD); 4152 } 4153 4154 // If the field is already invalid for some reason, don't emit more 4155 // diagnostics about it. 4156 if (FD->isInvalidDecl()) 4157 continue; 4158 4159 // C99 6.7.2.1p2: 4160 // A structure or union shall not contain a member with 4161 // incomplete or function type (hence, a structure shall not 4162 // contain an instance of itself, but may contain a pointer to 4163 // an instance of itself), except that the last member of a 4164 // structure with more than one named member may have incomplete 4165 // array type; such a structure (and any union containing, 4166 // possibly recursively, a member that is such a structure) 4167 // shall not be a member of a structure or an element of an 4168 // array. 4169 if (FDTy->isFunctionType()) { 4170 // Field declared as a function. 4171 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4172 << FD->getDeclName(); 4173 FD->setInvalidDecl(); 4174 EnclosingDecl->setInvalidDecl(); 4175 continue; 4176 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4177 Record && Record->isStruct()) { 4178 // Flexible array member. 4179 if (NumNamedMembers < 1) { 4180 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4181 << FD->getDeclName(); 4182 FD->setInvalidDecl(); 4183 EnclosingDecl->setInvalidDecl(); 4184 continue; 4185 } 4186 // Okay, we have a legal flexible array member at the end of the struct. 4187 if (Record) 4188 Record->setHasFlexibleArrayMember(true); 4189 } else if (!FDTy->isDependentType() && 4190 RequireCompleteType(FD->getLocation(), FD->getType(), 4191 diag::err_field_incomplete)) { 4192 // Incomplete type 4193 FD->setInvalidDecl(); 4194 EnclosingDecl->setInvalidDecl(); 4195 continue; 4196 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4197 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4198 // If this is a member of a union, then entire union becomes "flexible". 4199 if (Record && Record->isUnion()) { 4200 Record->setHasFlexibleArrayMember(true); 4201 } else { 4202 // If this is a struct/class and this is not the last element, reject 4203 // it. Note that GCC supports variable sized arrays in the middle of 4204 // structures. 4205 if (i != NumFields-1) 4206 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4207 << FD->getDeclName() << FD->getType(); 4208 else { 4209 // We support flexible arrays at the end of structs in 4210 // other structs as an extension. 4211 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4212 << FD->getDeclName(); 4213 if (Record) 4214 Record->setHasFlexibleArrayMember(true); 4215 } 4216 } 4217 } 4218 } else if (FDTy->isObjCInterfaceType()) { 4219 /// A field cannot be an Objective-c object 4220 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4221 FD->setInvalidDecl(); 4222 EnclosingDecl->setInvalidDecl(); 4223 continue; 4224 } 4225 // Keep track of the number of named members. 4226 if (FD->getIdentifier()) 4227 ++NumNamedMembers; 4228 } 4229 4230 // Okay, we successfully defined 'Record'. 4231 if (Record) { 4232 Record->completeDefinition(Context); 4233 } else { 4234 ObjCIvarDecl **ClsFields = 4235 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4236 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4237 ID->setIVarList(ClsFields, RecFields.size(), Context); 4238 ID->setLocEnd(RBrac); 4239 // Add ivar's to class's DeclContext. 4240 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4241 ClsFields[i]->setLexicalDeclContext(ID); 4242 ID->addDecl(Context, ClsFields[i]); 4243 } 4244 // Must enforce the rule that ivars in the base classes may not be 4245 // duplicates. 4246 if (ID->getSuperClass()) { 4247 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4248 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4249 ObjCIvarDecl* Ivar = (*IVI); 4250 4251 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4252 ObjCIvarDecl* prevIvar = 4253 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4254 if (prevIvar) { 4255 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4256 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4257 } 4258 } 4259 } 4260 } 4261 } else if (ObjCImplementationDecl *IMPDecl = 4262 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4263 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4264 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4265 // Ivar declared in @implementation never belongs to the implementation. 4266 // Only it is in implementation's lexical context. 4267 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4268 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4269 } 4270 } 4271 4272 if (Attr) 4273 ProcessDeclAttributeList(S, Record, Attr); 4274} 4275 4276EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4277 EnumConstantDecl *LastEnumConst, 4278 SourceLocation IdLoc, 4279 IdentifierInfo *Id, 4280 ExprArg val) { 4281 Expr *Val = (Expr *)val.get(); 4282 4283 llvm::APSInt EnumVal(32); 4284 QualType EltTy; 4285 if (Val && !Val->isTypeDependent()) { 4286 // Make sure to promote the operand type to int. 4287 UsualUnaryConversions(Val); 4288 if (Val != val.get()) { 4289 val.release(); 4290 val = Val; 4291 } 4292 4293 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4294 SourceLocation ExpLoc; 4295 if (!Val->isValueDependent() && 4296 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4297 Val = 0; 4298 } else { 4299 EltTy = Val->getType(); 4300 } 4301 } 4302 4303 if (!Val) { 4304 if (LastEnumConst) { 4305 // Assign the last value + 1. 4306 EnumVal = LastEnumConst->getInitVal(); 4307 ++EnumVal; 4308 4309 // Check for overflow on increment. 4310 if (EnumVal < LastEnumConst->getInitVal()) 4311 Diag(IdLoc, diag::warn_enum_value_overflow); 4312 4313 EltTy = LastEnumConst->getType(); 4314 } else { 4315 // First value, set to zero. 4316 EltTy = Context.IntTy; 4317 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4318 } 4319 } 4320 4321 val.release(); 4322 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4323 Val, EnumVal); 4324} 4325 4326 4327Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4328 DeclPtrTy lastEnumConst, 4329 SourceLocation IdLoc, 4330 IdentifierInfo *Id, 4331 SourceLocation EqualLoc, ExprTy *val) { 4332 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4333 EnumConstantDecl *LastEnumConst = 4334 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4335 Expr *Val = static_cast<Expr*>(val); 4336 4337 // The scope passed in may not be a decl scope. Zip up the scope tree until 4338 // we find one that is. 4339 S = getNonFieldDeclScope(S); 4340 4341 // Verify that there isn't already something declared with this name in this 4342 // scope. 4343 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4344 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4345 // Maybe we will complain about the shadowed template parameter. 4346 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4347 // Just pretend that we didn't see the previous declaration. 4348 PrevDecl = 0; 4349 } 4350 4351 if (PrevDecl) { 4352 // When in C++, we may get a TagDecl with the same name; in this case the 4353 // enum constant will 'hide' the tag. 4354 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4355 "Received TagDecl when not in C++!"); 4356 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4357 if (isa<EnumConstantDecl>(PrevDecl)) 4358 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4359 else 4360 Diag(IdLoc, diag::err_redefinition) << Id; 4361 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4362 if (Val) Val->Destroy(Context); 4363 return DeclPtrTy(); 4364 } 4365 } 4366 4367 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4368 IdLoc, Id, Owned(Val)); 4369 4370 // Register this decl in the current scope stack. 4371 if (New) 4372 PushOnScopeChains(New, S); 4373 4374 return DeclPtrTy::make(New); 4375} 4376 4377void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 4378 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 4379 DeclPtrTy *Elements, unsigned NumElements) { 4380 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4381 QualType EnumType = Context.getTypeDeclType(Enum); 4382 4383 // TODO: If the result value doesn't fit in an int, it must be a long or long 4384 // long value. ISO C does not support this, but GCC does as an extension, 4385 // emit a warning. 4386 unsigned IntWidth = Context.Target.getIntWidth(); 4387 4388 // Verify that all the values are okay, compute the size of the values, and 4389 // reverse the list. 4390 unsigned NumNegativeBits = 0; 4391 unsigned NumPositiveBits = 0; 4392 4393 // Keep track of whether all elements have type int. 4394 bool AllElementsInt = true; 4395 4396 for (unsigned i = 0; i != NumElements; ++i) { 4397 EnumConstantDecl *ECD = 4398 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4399 if (!ECD) continue; // Already issued a diagnostic. 4400 4401 // If the enum value doesn't fit in an int, emit an extension warning. 4402 const llvm::APSInt &InitVal = ECD->getInitVal(); 4403 assert(InitVal.getBitWidth() >= IntWidth && 4404 "Should have promoted value to int"); 4405 if (InitVal.getBitWidth() > IntWidth) { 4406 llvm::APSInt V(InitVal); 4407 V.trunc(IntWidth); 4408 V.extend(InitVal.getBitWidth()); 4409 if (V != InitVal) 4410 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4411 << InitVal.toString(10); 4412 } 4413 4414 // Keep track of the size of positive and negative values. 4415 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4416 NumPositiveBits = std::max(NumPositiveBits, 4417 (unsigned)InitVal.getActiveBits()); 4418 else 4419 NumNegativeBits = std::max(NumNegativeBits, 4420 (unsigned)InitVal.getMinSignedBits()); 4421 4422 // Keep track of whether every enum element has type int (very commmon). 4423 if (AllElementsInt) 4424 AllElementsInt = ECD->getType() == Context.IntTy; 4425 } 4426 4427 // Figure out the type that should be used for this enum. 4428 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4429 QualType BestType; 4430 unsigned BestWidth; 4431 4432 if (NumNegativeBits) { 4433 // If there is a negative value, figure out the smallest integer type (of 4434 // int/long/longlong) that fits. 4435 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4436 BestType = Context.IntTy; 4437 BestWidth = IntWidth; 4438 } else { 4439 BestWidth = Context.Target.getLongWidth(); 4440 4441 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4442 BestType = Context.LongTy; 4443 else { 4444 BestWidth = Context.Target.getLongLongWidth(); 4445 4446 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4447 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4448 BestType = Context.LongLongTy; 4449 } 4450 } 4451 } else { 4452 // If there is no negative value, figure out which of uint, ulong, ulonglong 4453 // fits. 4454 if (NumPositiveBits <= IntWidth) { 4455 BestType = Context.UnsignedIntTy; 4456 BestWidth = IntWidth; 4457 } else if (NumPositiveBits <= 4458 (BestWidth = Context.Target.getLongWidth())) { 4459 BestType = Context.UnsignedLongTy; 4460 } else { 4461 BestWidth = Context.Target.getLongLongWidth(); 4462 assert(NumPositiveBits <= BestWidth && 4463 "How could an initializer get larger than ULL?"); 4464 BestType = Context.UnsignedLongLongTy; 4465 } 4466 } 4467 4468 // Loop over all of the enumerator constants, changing their types to match 4469 // the type of the enum if needed. 4470 for (unsigned i = 0; i != NumElements; ++i) { 4471 EnumConstantDecl *ECD = 4472 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4473 if (!ECD) continue; // Already issued a diagnostic. 4474 4475 // Standard C says the enumerators have int type, but we allow, as an 4476 // extension, the enumerators to be larger than int size. If each 4477 // enumerator value fits in an int, type it as an int, otherwise type it the 4478 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4479 // that X has type 'int', not 'unsigned'. 4480 if (ECD->getType() == Context.IntTy) { 4481 // Make sure the init value is signed. 4482 llvm::APSInt IV = ECD->getInitVal(); 4483 IV.setIsSigned(true); 4484 ECD->setInitVal(IV); 4485 4486 if (getLangOptions().CPlusPlus) 4487 // C++ [dcl.enum]p4: Following the closing brace of an 4488 // enum-specifier, each enumerator has the type of its 4489 // enumeration. 4490 ECD->setType(EnumType); 4491 continue; // Already int type. 4492 } 4493 4494 // Determine whether the value fits into an int. 4495 llvm::APSInt InitVal = ECD->getInitVal(); 4496 bool FitsInInt; 4497 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4498 FitsInInt = InitVal.getActiveBits() < IntWidth; 4499 else 4500 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4501 4502 // If it fits into an integer type, force it. Otherwise force it to match 4503 // the enum decl type. 4504 QualType NewTy; 4505 unsigned NewWidth; 4506 bool NewSign; 4507 if (FitsInInt) { 4508 NewTy = Context.IntTy; 4509 NewWidth = IntWidth; 4510 NewSign = true; 4511 } else if (ECD->getType() == BestType) { 4512 // Already the right type! 4513 if (getLangOptions().CPlusPlus) 4514 // C++ [dcl.enum]p4: Following the closing brace of an 4515 // enum-specifier, each enumerator has the type of its 4516 // enumeration. 4517 ECD->setType(EnumType); 4518 continue; 4519 } else { 4520 NewTy = BestType; 4521 NewWidth = BestWidth; 4522 NewSign = BestType->isSignedIntegerType(); 4523 } 4524 4525 // Adjust the APSInt value. 4526 InitVal.extOrTrunc(NewWidth); 4527 InitVal.setIsSigned(NewSign); 4528 ECD->setInitVal(InitVal); 4529 4530 // Adjust the Expr initializer and type. 4531 if (ECD->getInitExpr()) 4532 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4533 /*isLvalue=*/false)); 4534 if (getLangOptions().CPlusPlus) 4535 // C++ [dcl.enum]p4: Following the closing brace of an 4536 // enum-specifier, each enumerator has the type of its 4537 // enumeration. 4538 ECD->setType(EnumType); 4539 else 4540 ECD->setType(NewTy); 4541 } 4542 4543 Enum->completeDefinition(Context, BestType); 4544} 4545 4546Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4547 ExprArg expr) { 4548 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4549 4550 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 4551 Loc, AsmString); 4552 CurContext->addDecl(Context, New); 4553 return DeclPtrTy::make(New); 4554} 4555 4556void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 4557 SourceLocation PragmaLoc, 4558 SourceLocation NameLoc) { 4559 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4560 4561 // FIXME: This implementation is an ugly hack! 4562 if (PrevDecl) { 4563 PrevDecl->addAttr(Context, ::new (Context) WeakAttr()); 4564 return; 4565 } 4566 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4567 return; 4568} 4569 4570void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 4571 IdentifierInfo* AliasName, 4572 SourceLocation PragmaLoc, 4573 SourceLocation NameLoc, 4574 SourceLocation AliasNameLoc) { 4575 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4576 4577 // FIXME: This implementation is an ugly hack! 4578 if (PrevDecl) { 4579 PrevDecl->addAttr(Context, ::new (Context) AliasAttr(AliasName->getName())); 4580 PrevDecl->addAttr(Context, ::new (Context) WeakAttr()); 4581 return; 4582 } 4583 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4584 return; 4585} 4586