SemaDecl.cpp revision 953d12aabb8cb25f0713a0913c837d2fdf8996b2
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>() != 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(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(const Decl *decl, const Attr *target) { 616 for (const Attr *attr = decl->getAttrs(); 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(); attr; attr = attr->getNext()) { 626 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 627 Attr *NewAttr = attr->clone(C); 628 NewAttr->setInherited(true); 629 New->addAttr(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(), 1127 FEnd = AnonRecord->field_end(); 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(*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(), 1217 MemEnd = Record->decls_end(); 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(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 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1436 NameKind = LookupRedeclarationWithLinkage; 1437 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1438 NameKind = LookupRedeclarationWithLinkage; 1439 else if (CurContext->getLookupContext()->isTranslationUnit() && 1440 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1441 NameKind = LookupRedeclarationWithLinkage; 1442 1443 DC = CurContext; 1444 PrevDecl = LookupName(S, Name, NameKind, true, 1445 NameKind == LookupRedeclarationWithLinkage, 1446 D.getIdentifierLoc()); 1447 } else { // Something like "int foo::x;" 1448 DC = computeDeclContext(D.getCXXScopeSpec()); 1449 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1450 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1451 1452 // C++ 7.3.1.2p2: 1453 // Members (including explicit specializations of templates) of a named 1454 // namespace can also be defined outside that namespace by explicit 1455 // qualification of the name being defined, provided that the entity being 1456 // defined was already declared in the namespace and the definition appears 1457 // after the point of declaration in a namespace that encloses the 1458 // declarations namespace. 1459 // 1460 // Note that we only check the context at this point. We don't yet 1461 // have enough information to make sure that PrevDecl is actually 1462 // the declaration we want to match. For example, given: 1463 // 1464 // class X { 1465 // void f(); 1466 // void f(float); 1467 // }; 1468 // 1469 // void X::f(int) { } // ill-formed 1470 // 1471 // In this case, PrevDecl will point to the overload set 1472 // containing the two f's declared in X, but neither of them 1473 // matches. 1474 1475 // First check whether we named the global scope. 1476 if (isa<TranslationUnitDecl>(DC)) { 1477 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1478 << Name << D.getCXXScopeSpec().getRange(); 1479 } else if (!CurContext->Encloses(DC)) { 1480 // The qualifying scope doesn't enclose the original declaration. 1481 // Emit diagnostic based on current scope. 1482 SourceLocation L = D.getIdentifierLoc(); 1483 SourceRange R = D.getCXXScopeSpec().getRange(); 1484 if (isa<FunctionDecl>(CurContext)) 1485 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1486 else 1487 Diag(L, diag::err_invalid_declarator_scope) 1488 << Name << cast<NamedDecl>(DC) << R; 1489 D.setInvalidType(); 1490 } 1491 } 1492 1493 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1494 // Maybe we will complain about the shadowed template parameter. 1495 if (!D.isInvalidType()) 1496 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1497 D.setInvalidType(); 1498 1499 // Just pretend that we didn't see the previous declaration. 1500 PrevDecl = 0; 1501 } 1502 1503 // In C++, the previous declaration we find might be a tag type 1504 // (class or enum). In this case, the new declaration will hide the 1505 // tag type. Note that this does does not apply if we're declaring a 1506 // typedef (C++ [dcl.typedef]p4). 1507 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1508 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1509 PrevDecl = 0; 1510 1511 bool Redeclaration = false; 1512 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1513 if (TemplateParamLists.size()) { 1514 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1515 return DeclPtrTy(); 1516 } 1517 1518 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1519 } else if (R->isFunctionType()) { 1520 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1521 move(TemplateParamLists), 1522 IsFunctionDefinition, Redeclaration); 1523 } else { 1524 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1525 } 1526 1527 if (New == 0) 1528 return DeclPtrTy(); 1529 1530 // If this has an identifier and is not an invalid redeclaration, 1531 // add it to the scope stack. 1532 if (Name && !(Redeclaration && New->isInvalidDecl())) 1533 PushOnScopeChains(New, S); 1534 1535 return DeclPtrTy::make(New); 1536} 1537 1538/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1539/// types into constant array types in certain situations which would otherwise 1540/// be errors (for GCC compatibility). 1541static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1542 ASTContext &Context, 1543 bool &SizeIsNegative) { 1544 // This method tries to turn a variable array into a constant 1545 // array even when the size isn't an ICE. This is necessary 1546 // for compatibility with code that depends on gcc's buggy 1547 // constant expression folding, like struct {char x[(int)(char*)2];} 1548 SizeIsNegative = false; 1549 1550 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1551 QualType Pointee = PTy->getPointeeType(); 1552 QualType FixedType = 1553 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1554 if (FixedType.isNull()) return FixedType; 1555 FixedType = Context.getPointerType(FixedType); 1556 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1557 return FixedType; 1558 } 1559 1560 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1561 if (!VLATy) 1562 return QualType(); 1563 // FIXME: We should probably handle this case 1564 if (VLATy->getElementType()->isVariablyModifiedType()) 1565 return QualType(); 1566 1567 Expr::EvalResult EvalResult; 1568 if (!VLATy->getSizeExpr() || 1569 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1570 !EvalResult.Val.isInt()) 1571 return QualType(); 1572 1573 llvm::APSInt &Res = EvalResult.Val.getInt(); 1574 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1575 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1576 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1577 // so as to transfer ownership to the ConstantArrayWithExpr. 1578 // Alternatively, we could "clone" it (how?). 1579 // Since we don't know how to do things above, we just use the 1580 // very same Expr*. 1581 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1582 Res, ArySizeExpr, 1583 ArrayType::Normal, 0, 1584 VLATy->getBracketsRange()); 1585 } 1586 1587 SizeIsNegative = true; 1588 return QualType(); 1589} 1590 1591/// \brief Register the given locally-scoped external C declaration so 1592/// that it can be found later for redeclarations 1593void 1594Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1595 Scope *S) { 1596 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1597 "Decl is not a locally-scoped decl!"); 1598 // Note that we have a locally-scoped external with this name. 1599 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1600 1601 if (!PrevDecl) 1602 return; 1603 1604 // If there was a previous declaration of this variable, it may be 1605 // in our identifier chain. Update the identifier chain with the new 1606 // declaration. 1607 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1608 // The previous declaration was found on the identifer resolver 1609 // chain, so remove it from its scope. 1610 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1611 S = S->getParent(); 1612 1613 if (S) 1614 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1615 } 1616} 1617 1618/// \brief Diagnose function specifiers on a declaration of an identifier that 1619/// does not identify a function. 1620void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1621 // FIXME: We should probably indicate the identifier in question to avoid 1622 // confusion for constructs like "inline int a(), b;" 1623 if (D.getDeclSpec().isInlineSpecified()) 1624 Diag(D.getDeclSpec().getInlineSpecLoc(), 1625 diag::err_inline_non_function); 1626 1627 if (D.getDeclSpec().isVirtualSpecified()) 1628 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1629 diag::err_virtual_non_function); 1630 1631 if (D.getDeclSpec().isExplicitSpecified()) 1632 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1633 diag::err_explicit_non_function); 1634} 1635 1636NamedDecl* 1637Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1638 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1639 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1640 if (D.getCXXScopeSpec().isSet()) { 1641 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1642 << D.getCXXScopeSpec().getRange(); 1643 D.setInvalidType(); 1644 // Pretend we didn't see the scope specifier. 1645 DC = 0; 1646 } 1647 1648 if (getLangOptions().CPlusPlus) { 1649 // Check that there are no default arguments (C++ only). 1650 CheckExtraCXXDefaultArguments(D); 1651 } 1652 1653 DiagnoseFunctionSpecifiers(D); 1654 1655 if (D.getDeclSpec().isThreadSpecified()) 1656 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1657 1658 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1659 if (!NewTD) return 0; 1660 1661 if (D.isInvalidType()) 1662 NewTD->setInvalidDecl(); 1663 1664 // Handle attributes prior to checking for duplicates in MergeVarDecl 1665 ProcessDeclAttributes(S, NewTD, D); 1666 // Merge the decl with the existing one if appropriate. If the decl is 1667 // in an outer scope, it isn't the same thing. 1668 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1669 Redeclaration = true; 1670 MergeTypeDefDecl(NewTD, PrevDecl); 1671 } 1672 1673 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1674 // then it shall have block scope. 1675 QualType T = NewTD->getUnderlyingType(); 1676 if (T->isVariablyModifiedType()) { 1677 CurFunctionNeedsScopeChecking = true; 1678 1679 if (S->getFnParent() == 0) { 1680 bool SizeIsNegative; 1681 QualType FixedTy = 1682 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1683 if (!FixedTy.isNull()) { 1684 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1685 NewTD->setUnderlyingType(FixedTy); 1686 } else { 1687 if (SizeIsNegative) 1688 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1689 else if (T->isVariableArrayType()) 1690 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1691 else 1692 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1693 NewTD->setInvalidDecl(); 1694 } 1695 } 1696 } 1697 1698 // If this is the C FILE type, notify the AST context. 1699 if (IdentifierInfo *II = NewTD->getIdentifier()) 1700 if (!NewTD->isInvalidDecl() && 1701 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit() && 1702 II->isStr("FILE")) 1703 Context.setFILEDecl(NewTD); 1704 1705 return NewTD; 1706} 1707 1708/// \brief Determines whether the given declaration is an out-of-scope 1709/// previous declaration. 1710/// 1711/// This routine should be invoked when name lookup has found a 1712/// previous declaration (PrevDecl) that is not in the scope where a 1713/// new declaration by the same name is being introduced. If the new 1714/// declaration occurs in a local scope, previous declarations with 1715/// linkage may still be considered previous declarations (C99 1716/// 6.2.2p4-5, C++ [basic.link]p6). 1717/// 1718/// \param PrevDecl the previous declaration found by name 1719/// lookup 1720/// 1721/// \param DC the context in which the new declaration is being 1722/// declared. 1723/// 1724/// \returns true if PrevDecl is an out-of-scope previous declaration 1725/// for a new delcaration with the same name. 1726static bool 1727isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1728 ASTContext &Context) { 1729 if (!PrevDecl) 1730 return 0; 1731 1732 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1733 // case we need to check each of the overloaded functions. 1734 if (!PrevDecl->hasLinkage()) 1735 return false; 1736 1737 if (Context.getLangOptions().CPlusPlus) { 1738 // C++ [basic.link]p6: 1739 // If there is a visible declaration of an entity with linkage 1740 // having the same name and type, ignoring entities declared 1741 // outside the innermost enclosing namespace scope, the block 1742 // scope declaration declares that same entity and receives the 1743 // linkage of the previous declaration. 1744 DeclContext *OuterContext = DC->getLookupContext(); 1745 if (!OuterContext->isFunctionOrMethod()) 1746 // This rule only applies to block-scope declarations. 1747 return false; 1748 else { 1749 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1750 if (PrevOuterContext->isRecord()) 1751 // We found a member function: ignore it. 1752 return false; 1753 else { 1754 // Find the innermost enclosing namespace for the new and 1755 // previous declarations. 1756 while (!OuterContext->isFileContext()) 1757 OuterContext = OuterContext->getParent(); 1758 while (!PrevOuterContext->isFileContext()) 1759 PrevOuterContext = PrevOuterContext->getParent(); 1760 1761 // The previous declaration is in a different namespace, so it 1762 // isn't the same function. 1763 if (OuterContext->getPrimaryContext() != 1764 PrevOuterContext->getPrimaryContext()) 1765 return false; 1766 } 1767 } 1768 } 1769 1770 return true; 1771} 1772 1773NamedDecl* 1774Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1775 QualType R,NamedDecl* PrevDecl, 1776 bool &Redeclaration) { 1777 DeclarationName Name = GetNameForDeclarator(D); 1778 1779 // Check that there are no default arguments (C++ only). 1780 if (getLangOptions().CPlusPlus) 1781 CheckExtraCXXDefaultArguments(D); 1782 1783 VarDecl *NewVD; 1784 VarDecl::StorageClass SC; 1785 switch (D.getDeclSpec().getStorageClassSpec()) { 1786 default: assert(0 && "Unknown storage class!"); 1787 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1788 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1789 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1790 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1791 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1792 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1793 case DeclSpec::SCS_mutable: 1794 // mutable can only appear on non-static class members, so it's always 1795 // an error here 1796 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1797 D.setInvalidType(); 1798 SC = VarDecl::None; 1799 break; 1800 } 1801 1802 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1803 if (!II) { 1804 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1805 << Name.getAsString(); 1806 return 0; 1807 } 1808 1809 DiagnoseFunctionSpecifiers(D); 1810 1811 if (!DC->isRecord() && S->getFnParent() == 0) { 1812 // C99 6.9p2: The storage-class specifiers auto and register shall not 1813 // appear in the declaration specifiers in an external declaration. 1814 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1815 1816 // If this is a register variable with an asm label specified, then this 1817 // is a GNU extension. 1818 if (SC == VarDecl::Register && D.getAsmLabel()) 1819 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1820 else 1821 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1822 D.setInvalidType(); 1823 } 1824 } 1825 if (DC->isRecord() && !CurContext->isRecord()) { 1826 // This is an out-of-line definition of a static data member. 1827 if (SC == VarDecl::Static) { 1828 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1829 diag::err_static_out_of_line) 1830 << CodeModificationHint::CreateRemoval( 1831 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1832 } else if (SC == VarDecl::None) 1833 SC = VarDecl::Static; 1834 } 1835 if (SC == VarDecl::Static) { 1836 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 1837 if (RD->isLocalClass()) 1838 Diag(D.getIdentifierLoc(), 1839 diag::err_static_data_member_not_allowed_in_local_class) 1840 << Name << RD->getDeclName(); 1841 } 1842 } 1843 1844 1845 // The variable can not 1846 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1847 II, R, SC, 1848 // FIXME: Move to DeclGroup... 1849 D.getDeclSpec().getSourceRange().getBegin()); 1850 1851 if (D.isInvalidType()) 1852 NewVD->setInvalidDecl(); 1853 1854 if (D.getDeclSpec().isThreadSpecified()) { 1855 if (NewVD->hasLocalStorage()) 1856 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1857 else if (!Context.Target.isTLSSupported()) 1858 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1859 else 1860 NewVD->setThreadSpecified(true); 1861 } 1862 1863 // Set the lexical context. If the declarator has a C++ scope specifier, the 1864 // lexical context will be different from the semantic context. 1865 NewVD->setLexicalDeclContext(CurContext); 1866 1867 // Handle attributes prior to checking for duplicates in MergeVarDecl 1868 ProcessDeclAttributes(S, NewVD, D); 1869 1870 // Handle GNU asm-label extension (encoded as an attribute). 1871 if (Expr *E = (Expr*) D.getAsmLabel()) { 1872 // The parser guarantees this is a string. 1873 StringLiteral *SE = cast<StringLiteral>(E); 1874 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1875 SE->getByteLength()))); 1876 } 1877 1878 // If name lookup finds a previous declaration that is not in the 1879 // same scope as the new declaration, this may still be an 1880 // acceptable redeclaration. 1881 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1882 !(NewVD->hasLinkage() && 1883 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1884 PrevDecl = 0; 1885 1886 // Merge the decl with the existing one if appropriate. 1887 if (PrevDecl) { 1888 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1889 // The user tried to define a non-static data member 1890 // out-of-line (C++ [dcl.meaning]p1). 1891 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1892 << D.getCXXScopeSpec().getRange(); 1893 PrevDecl = 0; 1894 NewVD->setInvalidDecl(); 1895 } 1896 } else if (D.getCXXScopeSpec().isSet()) { 1897 // No previous declaration in the qualifying scope. 1898 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1899 << Name << D.getCXXScopeSpec().getRange(); 1900 NewVD->setInvalidDecl(); 1901 } 1902 1903 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1904 1905 // If this is a locally-scoped extern C variable, update the map of 1906 // such variables. 1907 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1908 !NewVD->isInvalidDecl()) 1909 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1910 1911 return NewVD; 1912} 1913 1914/// \brief Perform semantic checking on a newly-created variable 1915/// declaration. 1916/// 1917/// This routine performs all of the type-checking required for a 1918/// variable declaration once it has been built. It is used both to 1919/// check variables after they have been parsed and their declarators 1920/// have been translated into a declaration, and to check variables 1921/// that have been instantiated from a template. 1922/// 1923/// Sets NewVD->isInvalidDecl() if an error was encountered. 1924void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1925 bool &Redeclaration) { 1926 // If the decl is already known invalid, don't check it. 1927 if (NewVD->isInvalidDecl()) 1928 return; 1929 1930 QualType T = NewVD->getType(); 1931 1932 if (T->isObjCInterfaceType()) { 1933 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1934 return NewVD->setInvalidDecl(); 1935 } 1936 1937 // The variable can not have an abstract class type. 1938 if (RequireNonAbstractType(NewVD->getLocation(), T, 1939 diag::err_abstract_type_in_decl, 1940 AbstractVariableType)) 1941 return NewVD->setInvalidDecl(); 1942 1943 // Emit an error if an address space was applied to decl with local storage. 1944 // This includes arrays of objects with address space qualifiers, but not 1945 // automatic variables that point to other address spaces. 1946 // ISO/IEC TR 18037 S5.1.2 1947 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1948 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1949 return NewVD->setInvalidDecl(); 1950 } 1951 1952 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1953 && !NewVD->hasAttr<BlocksAttr>()) 1954 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1955 1956 bool isVM = T->isVariablyModifiedType(); 1957 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1958 CurFunctionNeedsScopeChecking = true; 1959 1960 if ((isVM && NewVD->hasLinkage()) || 1961 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1962 bool SizeIsNegative; 1963 QualType FixedTy = 1964 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1965 1966 if (FixedTy.isNull() && T->isVariableArrayType()) { 1967 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1968 // FIXME: This won't give the correct result for 1969 // int a[10][n]; 1970 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1971 1972 if (NewVD->isFileVarDecl()) 1973 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1974 << SizeRange; 1975 else if (NewVD->getStorageClass() == VarDecl::Static) 1976 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1977 << SizeRange; 1978 else 1979 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1980 << SizeRange; 1981 return NewVD->setInvalidDecl(); 1982 } 1983 1984 if (FixedTy.isNull()) { 1985 if (NewVD->isFileVarDecl()) 1986 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1987 else 1988 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1989 return NewVD->setInvalidDecl(); 1990 } 1991 1992 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1993 NewVD->setType(FixedTy); 1994 } 1995 1996 if (!PrevDecl && NewVD->isExternC(Context)) { 1997 // Since we did not find anything by this name and we're declaring 1998 // an extern "C" variable, look for a non-visible extern "C" 1999 // declaration with the same name. 2000 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2001 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2002 if (Pos != LocallyScopedExternalDecls.end()) 2003 PrevDecl = Pos->second; 2004 } 2005 2006 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2007 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2008 << T; 2009 return NewVD->setInvalidDecl(); 2010 } 2011 2012 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2013 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2014 return NewVD->setInvalidDecl(); 2015 } 2016 2017 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2018 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2019 return NewVD->setInvalidDecl(); 2020 } 2021 2022 if (PrevDecl) { 2023 Redeclaration = true; 2024 MergeVarDecl(NewVD, PrevDecl); 2025 } 2026} 2027 2028NamedDecl* 2029Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2030 QualType R, NamedDecl* PrevDecl, 2031 MultiTemplateParamsArg TemplateParamLists, 2032 bool IsFunctionDefinition, bool &Redeclaration) { 2033 assert(R.getTypePtr()->isFunctionType()); 2034 2035 DeclarationName Name = GetNameForDeclarator(D); 2036 FunctionDecl::StorageClass SC = FunctionDecl::None; 2037 switch (D.getDeclSpec().getStorageClassSpec()) { 2038 default: assert(0 && "Unknown storage class!"); 2039 case DeclSpec::SCS_auto: 2040 case DeclSpec::SCS_register: 2041 case DeclSpec::SCS_mutable: 2042 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2043 diag::err_typecheck_sclass_func); 2044 D.setInvalidType(); 2045 break; 2046 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2047 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2048 case DeclSpec::SCS_static: { 2049 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2050 // C99 6.7.1p5: 2051 // The declaration of an identifier for a function that has 2052 // block scope shall have no explicit storage-class specifier 2053 // other than extern 2054 // See also (C++ [dcl.stc]p4). 2055 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2056 diag::err_static_block_func); 2057 SC = FunctionDecl::None; 2058 } else 2059 SC = FunctionDecl::Static; 2060 break; 2061 } 2062 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2063 } 2064 2065 if (D.getDeclSpec().isThreadSpecified()) 2066 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2067 2068 bool isInline = D.getDeclSpec().isInlineSpecified(); 2069 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2070 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2071 2072 // Check that the return type is not an abstract class type. 2073 // For record types, this is done by the AbstractClassUsageDiagnoser once 2074 // the class has been completely parsed. 2075 if (!DC->isRecord() && 2076 RequireNonAbstractType(D.getIdentifierLoc(), 2077 R->getAsFunctionType()->getResultType(), 2078 diag::err_abstract_type_in_decl, 2079 AbstractReturnType)) 2080 D.setInvalidType(); 2081 2082 // Do not allow returning a objc interface by-value. 2083 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2084 Diag(D.getIdentifierLoc(), 2085 diag::err_object_cannot_be_passed_returned_by_value) << 0 2086 << R->getAsFunctionType()->getResultType(); 2087 D.setInvalidType(); 2088 } 2089 2090 // Check that we can declare a template here. 2091 if (TemplateParamLists.size() && 2092 CheckTemplateDeclScope(S, TemplateParamLists)) 2093 return 0; 2094 2095 bool isVirtualOkay = false; 2096 FunctionDecl *NewFD; 2097 if (D.getKind() == Declarator::DK_Constructor) { 2098 // This is a C++ constructor declaration. 2099 assert(DC->isRecord() && 2100 "Constructors can only be declared in a member context"); 2101 2102 R = CheckConstructorDeclarator(D, R, SC); 2103 2104 // Create the new declaration 2105 NewFD = CXXConstructorDecl::Create(Context, 2106 cast<CXXRecordDecl>(DC), 2107 D.getIdentifierLoc(), Name, R, 2108 isExplicit, isInline, 2109 /*isImplicitlyDeclared=*/false); 2110 } else if (D.getKind() == Declarator::DK_Destructor) { 2111 // This is a C++ destructor declaration. 2112 if (DC->isRecord()) { 2113 R = CheckDestructorDeclarator(D, SC); 2114 2115 NewFD = CXXDestructorDecl::Create(Context, 2116 cast<CXXRecordDecl>(DC), 2117 D.getIdentifierLoc(), Name, R, 2118 isInline, 2119 /*isImplicitlyDeclared=*/false); 2120 2121 isVirtualOkay = true; 2122 } else { 2123 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2124 2125 // Create a FunctionDecl to satisfy the function definition parsing 2126 // code path. 2127 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2128 Name, R, SC, isInline, 2129 /*hasPrototype=*/true, 2130 // FIXME: Move to DeclGroup... 2131 D.getDeclSpec().getSourceRange().getBegin()); 2132 D.setInvalidType(); 2133 } 2134 } else if (D.getKind() == Declarator::DK_Conversion) { 2135 if (!DC->isRecord()) { 2136 Diag(D.getIdentifierLoc(), 2137 diag::err_conv_function_not_member); 2138 return 0; 2139 } 2140 2141 CheckConversionDeclarator(D, R, SC); 2142 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2143 D.getIdentifierLoc(), Name, R, 2144 isInline, isExplicit); 2145 2146 isVirtualOkay = true; 2147 } else if (DC->isRecord()) { 2148 // If the of the function is the same as the name of the record, then this 2149 // must be an invalid constructor that has a return type. 2150 // (The parser checks for a return type and makes the declarator a 2151 // constructor if it has no return type). 2152 // must have an invalid constructor that has a return type 2153 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2154 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2155 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2156 << SourceRange(D.getIdentifierLoc()); 2157 return 0; 2158 } 2159 2160 // This is a C++ method declaration. 2161 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2162 D.getIdentifierLoc(), Name, R, 2163 (SC == FunctionDecl::Static), isInline); 2164 2165 isVirtualOkay = (SC != FunctionDecl::Static); 2166 } else { 2167 // Determine whether the function was written with a 2168 // prototype. This true when: 2169 // - we're in C++ (where every function has a prototype), 2170 // - there is a prototype in the declarator, or 2171 // - the type R of the function is some kind of typedef or other reference 2172 // to a type name (which eventually refers to a function type). 2173 bool HasPrototype = 2174 getLangOptions().CPlusPlus || 2175 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2176 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2177 2178 NewFD = FunctionDecl::Create(Context, DC, 2179 D.getIdentifierLoc(), 2180 Name, R, SC, isInline, HasPrototype, 2181 // FIXME: Move to DeclGroup... 2182 D.getDeclSpec().getSourceRange().getBegin()); 2183 } 2184 2185 if (D.isInvalidType()) 2186 NewFD->setInvalidDecl(); 2187 2188 // Set the lexical context. If the declarator has a C++ 2189 // scope specifier, the lexical context will be different 2190 // from the semantic context. 2191 NewFD->setLexicalDeclContext(CurContext); 2192 2193 // If there is a template parameter list, then we are dealing with a 2194 // template declaration or specialization. 2195 FunctionTemplateDecl *FunctionTemplate = 0; 2196 if (TemplateParamLists.size()) { 2197 // FIXME: member templates! 2198 TemplateParameterList *TemplateParams 2199 = static_cast<TemplateParameterList *>(*TemplateParamLists.release()); 2200 2201 if (TemplateParams->size() > 0) { 2202 // This is a function template 2203 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2204 NewFD->getLocation(), 2205 Name, TemplateParams, 2206 NewFD); 2207 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2208 } else { 2209 // FIXME: Handle function template specializations 2210 } 2211 } 2212 2213 // C++ [dcl.fct.spec]p5: 2214 // The virtual specifier shall only be used in declarations of 2215 // nonstatic class member functions that appear within a 2216 // member-specification of a class declaration; see 10.3. 2217 // 2218 if (isVirtual && !NewFD->isInvalidDecl()) { 2219 if (!isVirtualOkay) { 2220 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2221 diag::err_virtual_non_function); 2222 } else if (!CurContext->isRecord()) { 2223 // 'virtual' was specified outside of the class. 2224 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2225 << CodeModificationHint::CreateRemoval( 2226 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2227 } else { 2228 // Okay: Add virtual to the method. 2229 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2230 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2231 CurClass->setAggregate(false); 2232 CurClass->setPOD(false); 2233 CurClass->setPolymorphic(true); 2234 CurClass->setHasTrivialConstructor(false); 2235 } 2236 } 2237 2238 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2239 // Look for virtual methods in base classes that this method might override. 2240 2241 BasePaths Paths; 2242 if (LookupInBases(cast<CXXRecordDecl>(DC), 2243 MemberLookupCriteria(NewMD), Paths)) { 2244 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2245 E = Paths.found_decls_end(); I != E; ++I) { 2246 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2247 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2248 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2249 NewMD->addOverriddenMethod(OldMD); 2250 } 2251 } 2252 } 2253 } 2254 2255 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2256 !CurContext->isRecord()) { 2257 // C++ [class.static]p1: 2258 // A data or function member of a class may be declared static 2259 // in a class definition, in which case it is a static member of 2260 // the class. 2261 2262 // Complain about the 'static' specifier if it's on an out-of-line 2263 // member function definition. 2264 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2265 diag::err_static_out_of_line) 2266 << CodeModificationHint::CreateRemoval( 2267 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2268 } 2269 2270 // Handle GNU asm-label extension (encoded as an attribute). 2271 if (Expr *E = (Expr*) D.getAsmLabel()) { 2272 // The parser guarantees this is a string. 2273 StringLiteral *SE = cast<StringLiteral>(E); 2274 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2275 SE->getByteLength()))); 2276 } 2277 2278 // Copy the parameter declarations from the declarator D to the function 2279 // declaration NewFD, if they are available. First scavenge them into Params. 2280 llvm::SmallVector<ParmVarDecl*, 16> Params; 2281 if (D.getNumTypeObjects() > 0) { 2282 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2283 2284 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2285 // function that takes no arguments, not a function that takes a 2286 // single void argument. 2287 // We let through "const void" here because Sema::GetTypeForDeclarator 2288 // already checks for that case. 2289 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2290 FTI.ArgInfo[0].Param && 2291 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2292 // Empty arg list, don't push any params. 2293 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2294 2295 // In C++, the empty parameter-type-list must be spelled "void"; a 2296 // typedef of void is not permitted. 2297 if (getLangOptions().CPlusPlus && 2298 Param->getType().getUnqualifiedType() != Context.VoidTy) 2299 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2300 // FIXME: Leaks decl? 2301 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2302 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2303 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2304 } 2305 2306 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2307 // When we're declaring a function with a typedef, typeof, etc as in the 2308 // following example, we'll need to synthesize (unnamed) 2309 // parameters for use in the declaration. 2310 // 2311 // @code 2312 // typedef void fn(int); 2313 // fn f; 2314 // @endcode 2315 2316 // Synthesize a parameter for each argument type. 2317 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2318 AE = FT->arg_type_end(); AI != AE; ++AI) { 2319 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2320 SourceLocation(), 0, 2321 *AI, VarDecl::None, 0); 2322 Param->setImplicit(); 2323 Params.push_back(Param); 2324 } 2325 } else { 2326 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2327 "Should not need args for typedef of non-prototype fn"); 2328 } 2329 // Finally, we know we have the right number of parameters, install them. 2330 NewFD->setParams(Context, Params.data(), Params.size()); 2331 2332 // If name lookup finds a previous declaration that is not in the 2333 // same scope as the new declaration, this may still be an 2334 // acceptable redeclaration. 2335 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2336 !(NewFD->hasLinkage() && 2337 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2338 PrevDecl = 0; 2339 2340 // Perform semantic checking on the function declaration. 2341 bool OverloadableAttrRequired = false; // FIXME: HACK! 2342 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2343 /*FIXME:*/OverloadableAttrRequired); 2344 2345 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2346 // An out-of-line member function declaration must also be a 2347 // definition (C++ [dcl.meaning]p1). 2348 if (!IsFunctionDefinition) { 2349 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2350 << D.getCXXScopeSpec().getRange(); 2351 NewFD->setInvalidDecl(); 2352 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2353 // The user tried to provide an out-of-line definition for a 2354 // function that is a member of a class or namespace, but there 2355 // was no such member function declared (C++ [class.mfct]p2, 2356 // C++ [namespace.memdef]p2). For example: 2357 // 2358 // class X { 2359 // void f() const; 2360 // }; 2361 // 2362 // void X::f() { } // ill-formed 2363 // 2364 // Complain about this problem, and attempt to suggest close 2365 // matches (e.g., those that differ only in cv-qualifiers and 2366 // whether the parameter types are references). 2367 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2368 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2369 NewFD->setInvalidDecl(); 2370 2371 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2372 true); 2373 assert(!Prev.isAmbiguous() && 2374 "Cannot have an ambiguity in previous-declaration lookup"); 2375 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2376 Func != FuncEnd; ++Func) { 2377 if (isa<FunctionDecl>(*Func) && 2378 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2379 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2380 } 2381 2382 PrevDecl = 0; 2383 } 2384 } 2385 2386 // Handle attributes. We need to have merged decls when handling attributes 2387 // (for example to check for conflicts, etc). 2388 // FIXME: This needs to happen before we merge declarations. Then, 2389 // let attribute merging cope with attribute conflicts. 2390 ProcessDeclAttributes(S, NewFD, D); 2391 AddKnownFunctionAttributes(NewFD); 2392 2393 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2394 // If a function name is overloadable in C, then every function 2395 // with that name must be marked "overloadable". 2396 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2397 << Redeclaration << NewFD; 2398 if (PrevDecl) 2399 Diag(PrevDecl->getLocation(), 2400 diag::note_attribute_overloadable_prev_overload); 2401 NewFD->addAttr(::new (Context) OverloadableAttr()); 2402 } 2403 2404 // If this is a locally-scoped extern C function, update the 2405 // map of such names. 2406 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2407 && !NewFD->isInvalidDecl()) 2408 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2409 2410 // Set this FunctionDecl's range up to the right paren. 2411 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2412 2413 if (FunctionTemplate && NewFD->isInvalidDecl()) 2414 FunctionTemplate->setInvalidDecl(); 2415 2416 if (FunctionTemplate) 2417 return FunctionTemplate; 2418 2419 return NewFD; 2420} 2421 2422/// \brief Perform semantic checking of a new function declaration. 2423/// 2424/// Performs semantic analysis of the new function declaration 2425/// NewFD. This routine performs all semantic checking that does not 2426/// require the actual declarator involved in the declaration, and is 2427/// used both for the declaration of functions as they are parsed 2428/// (called via ActOnDeclarator) and for the declaration of functions 2429/// that have been instantiated via C++ template instantiation (called 2430/// via InstantiateDecl). 2431/// 2432/// This sets NewFD->isInvalidDecl() to true if there was an error. 2433void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2434 bool &Redeclaration, 2435 bool &OverloadableAttrRequired) { 2436 // If NewFD is already known erroneous, don't do any of this checking. 2437 if (NewFD->isInvalidDecl()) 2438 return; 2439 2440 if (NewFD->getResultType()->isVariablyModifiedType()) { 2441 // Functions returning a variably modified type violate C99 6.7.5.2p2 2442 // because all functions have linkage. 2443 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2444 return NewFD->setInvalidDecl(); 2445 } 2446 2447 // Semantic checking for this function declaration (in isolation). 2448 if (getLangOptions().CPlusPlus) { 2449 // C++-specific checks. 2450 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2451 CheckConstructor(Constructor); 2452 } else if (isa<CXXDestructorDecl>(NewFD)) { 2453 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2454 Record->setUserDeclaredDestructor(true); 2455 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2456 // user-defined destructor. 2457 Record->setPOD(false); 2458 2459 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2460 // declared destructor. 2461 Record->setHasTrivialDestructor(false); 2462 } else if (CXXConversionDecl *Conversion 2463 = dyn_cast<CXXConversionDecl>(NewFD)) 2464 ActOnConversionDeclarator(Conversion); 2465 2466 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2467 if (NewFD->isOverloadedOperator() && 2468 CheckOverloadedOperatorDeclaration(NewFD)) 2469 return NewFD->setInvalidDecl(); 2470 } 2471 2472 // C99 6.7.4p6: 2473 // [... ] For a function with external linkage, the following 2474 // restrictions apply: [...] If all of the file scope declarations 2475 // for a function in a translation unit include the inline 2476 // function specifier without extern, then the definition in that 2477 // translation unit is an inline definition. An inline definition 2478 // does not provide an external definition for the function, and 2479 // does not forbid an external definition in another translation 2480 // unit. 2481 // 2482 // Here we determine whether this function, in isolation, would be a 2483 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2484 // previous declarations. 2485 if (NewFD->isInline() && getLangOptions().C99 && 2486 NewFD->getStorageClass() == FunctionDecl::None && 2487 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2488 NewFD->setC99InlineDefinition(true); 2489 2490 // Check for a previous declaration of this name. 2491 if (!PrevDecl && NewFD->isExternC(Context)) { 2492 // Since we did not find anything by this name and we're declaring 2493 // an extern "C" function, look for a non-visible extern "C" 2494 // declaration with the same name. 2495 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2496 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2497 if (Pos != LocallyScopedExternalDecls.end()) 2498 PrevDecl = Pos->second; 2499 } 2500 2501 // Merge or overload the declaration with an existing declaration of 2502 // the same name, if appropriate. 2503 if (PrevDecl) { 2504 // Determine whether NewFD is an overload of PrevDecl or 2505 // a declaration that requires merging. If it's an overload, 2506 // there's no more work to do here; we'll just add the new 2507 // function to the scope. 2508 OverloadedFunctionDecl::function_iterator MatchedDecl; 2509 2510 if (!getLangOptions().CPlusPlus && 2511 AllowOverloadingOfFunction(PrevDecl, Context)) { 2512 OverloadableAttrRequired = true; 2513 2514 // Functions marked "overloadable" must have a prototype (that 2515 // we can't get through declaration merging). 2516 if (!NewFD->getType()->getAsFunctionProtoType()) { 2517 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2518 << NewFD; 2519 Redeclaration = true; 2520 2521 // Turn this into a variadic function with no parameters. 2522 QualType R = Context.getFunctionType( 2523 NewFD->getType()->getAsFunctionType()->getResultType(), 2524 0, 0, true, 0); 2525 NewFD->setType(R); 2526 return NewFD->setInvalidDecl(); 2527 } 2528 } 2529 2530 if (PrevDecl && 2531 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2532 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2533 !isa<UsingDecl>(PrevDecl)) { 2534 Redeclaration = true; 2535 Decl *OldDecl = PrevDecl; 2536 2537 // If PrevDecl was an overloaded function, extract the 2538 // FunctionDecl that matched. 2539 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2540 OldDecl = *MatchedDecl; 2541 2542 // NewFD and OldDecl represent declarations that need to be 2543 // merged. 2544 if (MergeFunctionDecl(NewFD, OldDecl)) 2545 return NewFD->setInvalidDecl(); 2546 2547 if (FunctionTemplateDecl *OldTemplateDecl 2548 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2549 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2550 else 2551 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2552 } 2553 } 2554 2555 // In C++, check default arguments now that we have merged decls. Unless 2556 // the lexical context is the class, because in this case this is done 2557 // during delayed parsing anyway. 2558 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2559 CheckCXXDefaultArguments(NewFD); 2560} 2561 2562bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2563 // FIXME: Need strict checking. In C89, we need to check for 2564 // any assignment, increment, decrement, function-calls, or 2565 // commas outside of a sizeof. In C99, it's the same list, 2566 // except that the aforementioned are allowed in unevaluated 2567 // expressions. Everything else falls under the 2568 // "may accept other forms of constant expressions" exception. 2569 // (We never end up here for C++, so the constant expression 2570 // rules there don't matter.) 2571 if (Init->isConstantInitializer(Context)) 2572 return false; 2573 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2574 << Init->getSourceRange(); 2575 return true; 2576} 2577 2578void Sema::AddInitializerToDecl(DeclPtrTy dcl, FullExprArg init) { 2579 AddInitializerToDecl(dcl, init.release(), /*DirectInit=*/false); 2580} 2581 2582/// AddInitializerToDecl - Adds the initializer Init to the 2583/// declaration dcl. If DirectInit is true, this is C++ direct 2584/// initialization rather than copy initialization. 2585void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2586 Decl *RealDecl = dcl.getAs<Decl>(); 2587 // If there is no declaration, there was an error parsing it. Just ignore 2588 // the initializer. 2589 if (RealDecl == 0) 2590 return; 2591 2592 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2593 // With declarators parsed the way they are, the parser cannot 2594 // distinguish between a normal initializer and a pure-specifier. 2595 // Thus this grotesque test. 2596 IntegerLiteral *IL; 2597 Expr *Init = static_cast<Expr *>(init.get()); 2598 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2599 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2600 if (Method->isVirtualAsWritten()) { 2601 Method->setPure(); 2602 2603 // A class is abstract if at least one function is pure virtual. 2604 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2605 } else if (!Method->isInvalidDecl()) { 2606 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2607 << Method->getDeclName() << Init->getSourceRange(); 2608 Method->setInvalidDecl(); 2609 } 2610 } else { 2611 Diag(Method->getLocation(), diag::err_member_function_initialization) 2612 << Method->getDeclName() << Init->getSourceRange(); 2613 Method->setInvalidDecl(); 2614 } 2615 return; 2616 } 2617 2618 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2619 if (!VDecl) { 2620 if (getLangOptions().CPlusPlus && 2621 RealDecl->getLexicalDeclContext()->isRecord() && 2622 isa<NamedDecl>(RealDecl)) 2623 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2624 << cast<NamedDecl>(RealDecl)->getDeclName(); 2625 else 2626 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2627 RealDecl->setInvalidDecl(); 2628 return; 2629 } 2630 2631 if (!VDecl->getType()->isArrayType() && 2632 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2633 diag::err_typecheck_decl_incomplete_type)) { 2634 RealDecl->setInvalidDecl(); 2635 return; 2636 } 2637 2638 const VarDecl *Def = 0; 2639 if (VDecl->getDefinition(Def)) { 2640 Diag(VDecl->getLocation(), diag::err_redefinition) 2641 << VDecl->getDeclName(); 2642 Diag(Def->getLocation(), diag::note_previous_definition); 2643 VDecl->setInvalidDecl(); 2644 return; 2645 } 2646 2647 // Take ownership of the expression, now that we're sure we have somewhere 2648 // to put it. 2649 Expr *Init = init.takeAs<Expr>(); 2650 assert(Init && "missing initializer"); 2651 2652 // Get the decls type and save a reference for later, since 2653 // CheckInitializerTypes may change it. 2654 QualType DclT = VDecl->getType(), SavT = DclT; 2655 if (VDecl->isBlockVarDecl()) { 2656 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2657 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2658 VDecl->setInvalidDecl(); 2659 } else if (!VDecl->isInvalidDecl()) { 2660 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2661 VDecl->getDeclName(), DirectInit)) 2662 VDecl->setInvalidDecl(); 2663 2664 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2665 // Don't check invalid declarations to avoid emitting useless diagnostics. 2666 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2667 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2668 CheckForConstantInitializer(Init, DclT); 2669 } 2670 } 2671 } else if (VDecl->isStaticDataMember() && 2672 VDecl->getLexicalDeclContext()->isRecord()) { 2673 // This is an in-class initialization for a static data member, e.g., 2674 // 2675 // struct S { 2676 // static const int value = 17; 2677 // }; 2678 2679 // Attach the initializer 2680 VDecl->setInit(Context, Init); 2681 2682 // C++ [class.mem]p4: 2683 // A member-declarator can contain a constant-initializer only 2684 // if it declares a static member (9.4) of const integral or 2685 // const enumeration type, see 9.4.2. 2686 QualType T = VDecl->getType(); 2687 if (!T->isDependentType() && 2688 (!Context.getCanonicalType(T).isConstQualified() || 2689 !T->isIntegralType())) { 2690 Diag(VDecl->getLocation(), diag::err_member_initialization) 2691 << VDecl->getDeclName() << Init->getSourceRange(); 2692 VDecl->setInvalidDecl(); 2693 } else { 2694 // C++ [class.static.data]p4: 2695 // If a static data member is of const integral or const 2696 // enumeration type, its declaration in the class definition 2697 // can specify a constant-initializer which shall be an 2698 // integral constant expression (5.19). 2699 if (!Init->isTypeDependent() && 2700 !Init->getType()->isIntegralType()) { 2701 // We have a non-dependent, non-integral or enumeration type. 2702 Diag(Init->getSourceRange().getBegin(), 2703 diag::err_in_class_initializer_non_integral_type) 2704 << Init->getType() << Init->getSourceRange(); 2705 VDecl->setInvalidDecl(); 2706 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2707 // Check whether the expression is a constant expression. 2708 llvm::APSInt Value; 2709 SourceLocation Loc; 2710 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2711 Diag(Loc, diag::err_in_class_initializer_non_constant) 2712 << Init->getSourceRange(); 2713 VDecl->setInvalidDecl(); 2714 } else if (!VDecl->getType()->isDependentType()) 2715 ImpCastExprToType(Init, VDecl->getType()); 2716 } 2717 } 2718 } else if (VDecl->isFileVarDecl()) { 2719 if (VDecl->getStorageClass() == VarDecl::Extern) 2720 Diag(VDecl->getLocation(), diag::warn_extern_init); 2721 if (!VDecl->isInvalidDecl()) 2722 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2723 VDecl->getDeclName(), DirectInit)) 2724 VDecl->setInvalidDecl(); 2725 2726 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2727 // Don't check invalid declarations to avoid emitting useless diagnostics. 2728 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2729 // C99 6.7.8p4. All file scoped initializers need to be constant. 2730 CheckForConstantInitializer(Init, DclT); 2731 } 2732 } 2733 // If the type changed, it means we had an incomplete type that was 2734 // completed by the initializer. For example: 2735 // int ary[] = { 1, 3, 5 }; 2736 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2737 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2738 VDecl->setType(DclT); 2739 Init->setType(DclT); 2740 } 2741 2742 // Attach the initializer to the decl. 2743 VDecl->setInit(Context, Init); 2744 2745 // If the previous declaration of VDecl was a tentative definition, 2746 // remove it from the set of tentative definitions. 2747 if (VDecl->getPreviousDeclaration() && 2748 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2749 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2750 = TentativeDefinitions.find(VDecl->getDeclName()); 2751 assert(Pos != TentativeDefinitions.end() && 2752 "Unrecorded tentative definition?"); 2753 TentativeDefinitions.erase(Pos); 2754 } 2755 2756 return; 2757} 2758 2759void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2760 Decl *RealDecl = dcl.getAs<Decl>(); 2761 2762 // If there is no declaration, there was an error parsing it. Just ignore it. 2763 if (RealDecl == 0) 2764 return; 2765 2766 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2767 QualType Type = Var->getType(); 2768 2769 // Record tentative definitions. 2770 if (Var->isTentativeDefinition(Context)) 2771 TentativeDefinitions[Var->getDeclName()] = Var; 2772 2773 // C++ [dcl.init.ref]p3: 2774 // The initializer can be omitted for a reference only in a 2775 // parameter declaration (8.3.5), in the declaration of a 2776 // function return type, in the declaration of a class member 2777 // within its class declaration (9.2), and where the extern 2778 // specifier is explicitly used. 2779 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2780 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2781 << Var->getDeclName() 2782 << SourceRange(Var->getLocation(), Var->getLocation()); 2783 Var->setInvalidDecl(); 2784 return; 2785 } 2786 2787 // C++ [dcl.init]p9: 2788 // 2789 // If no initializer is specified for an object, and the object 2790 // is of (possibly cv-qualified) non-POD class type (or array 2791 // thereof), the object shall be default-initialized; if the 2792 // object is of const-qualified type, the underlying class type 2793 // shall have a user-declared default constructor. 2794 if (getLangOptions().CPlusPlus) { 2795 QualType InitType = Type; 2796 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2797 InitType = Array->getElementType(); 2798 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 2799 InitType->isRecordType() && !InitType->isDependentType()) { 2800 CXXRecordDecl *RD = 2801 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2802 CXXConstructorDecl *Constructor = 0; 2803 if (!RequireCompleteType(Var->getLocation(), InitType, 2804 diag::err_invalid_incomplete_type_use)) 2805 Constructor 2806 = PerformInitializationByConstructor(InitType, 0, 0, 2807 Var->getLocation(), 2808 SourceRange(Var->getLocation(), 2809 Var->getLocation()), 2810 Var->getDeclName(), 2811 IK_Default); 2812 if (!Constructor) 2813 Var->setInvalidDecl(); 2814 else { 2815 if (!RD->hasTrivialConstructor()) 2816 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2817 // FIXME. Must do all that is needed to destroy the object 2818 // on scope exit. For now, just mark the destructor as used. 2819 MarkDestructorReferenced(Var->getLocation(), InitType); 2820 } 2821 } 2822 } 2823 2824#if 0 2825 // FIXME: Temporarily disabled because we are not properly parsing 2826 // linkage specifications on declarations, e.g., 2827 // 2828 // extern "C" const CGPoint CGPointerZero; 2829 // 2830 // C++ [dcl.init]p9: 2831 // 2832 // If no initializer is specified for an object, and the 2833 // object is of (possibly cv-qualified) non-POD class type (or 2834 // array thereof), the object shall be default-initialized; if 2835 // the object is of const-qualified type, the underlying class 2836 // type shall have a user-declared default 2837 // constructor. Otherwise, if no initializer is specified for 2838 // an object, the object and its subobjects, if any, have an 2839 // indeterminate initial value; if the object or any of its 2840 // subobjects are of const-qualified type, the program is 2841 // ill-formed. 2842 // 2843 // This isn't technically an error in C, so we don't diagnose it. 2844 // 2845 // FIXME: Actually perform the POD/user-defined default 2846 // constructor check. 2847 if (getLangOptions().CPlusPlus && 2848 Context.getCanonicalType(Type).isConstQualified() && 2849 !Var->hasExternalStorage()) 2850 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2851 << Var->getName() 2852 << SourceRange(Var->getLocation(), Var->getLocation()); 2853#endif 2854 } 2855} 2856 2857Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 2858 DeclPtrTy *Group, 2859 unsigned NumDecls) { 2860 llvm::SmallVector<Decl*, 8> Decls; 2861 2862 if (DS.isTypeSpecOwned()) 2863 Decls.push_back((Decl*)DS.getTypeRep()); 2864 2865 for (unsigned i = 0; i != NumDecls; ++i) 2866 if (Decl *D = Group[i].getAs<Decl>()) 2867 Decls.push_back(D); 2868 2869 // Perform semantic analysis that depends on having fully processed both 2870 // the declarator and initializer. 2871 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2872 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2873 if (!IDecl) 2874 continue; 2875 QualType T = IDecl->getType(); 2876 2877 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2878 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2879 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2880 if (!IDecl->isInvalidDecl() && 2881 RequireCompleteType(IDecl->getLocation(), T, 2882 diag::err_typecheck_decl_incomplete_type)) 2883 IDecl->setInvalidDecl(); 2884 } 2885 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2886 // object that has file scope without an initializer, and without a 2887 // storage-class specifier or with the storage-class specifier "static", 2888 // constitutes a tentative definition. Note: A tentative definition with 2889 // external linkage is valid (C99 6.2.2p5). 2890 if (IDecl->isTentativeDefinition(Context)) { 2891 QualType CheckType = T; 2892 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2893 2894 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2895 if (ArrayT) { 2896 CheckType = ArrayT->getElementType(); 2897 DiagID = diag::err_illegal_decl_array_incomplete_type; 2898 } 2899 2900 if (IDecl->isInvalidDecl()) { 2901 // Do nothing with invalid declarations 2902 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2903 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2904 // C99 6.9.2p3: If the declaration of an identifier for an object is 2905 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2906 // declared type shall not be an incomplete type. 2907 IDecl->setInvalidDecl(); 2908 } 2909 } 2910 } 2911 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2912 Decls.data(), Decls.size())); 2913} 2914 2915 2916/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2917/// to introduce parameters into function prototype scope. 2918Sema::DeclPtrTy 2919Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2920 const DeclSpec &DS = D.getDeclSpec(); 2921 2922 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2923 VarDecl::StorageClass StorageClass = VarDecl::None; 2924 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2925 StorageClass = VarDecl::Register; 2926 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2927 Diag(DS.getStorageClassSpecLoc(), 2928 diag::err_invalid_storage_class_in_func_decl); 2929 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2930 } 2931 2932 if (D.getDeclSpec().isThreadSpecified()) 2933 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2934 2935 DiagnoseFunctionSpecifiers(D); 2936 2937 // Check that there are no default arguments inside the type of this 2938 // parameter (C++ only). 2939 if (getLangOptions().CPlusPlus) 2940 CheckExtraCXXDefaultArguments(D); 2941 2942 TagDecl *OwnedDecl = 0; 2943 QualType parmDeclType = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedDecl); 2944 2945 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 2946 // C++ [dcl.fct]p6: 2947 // Types shall not be defined in return or parameter types. 2948 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 2949 << Context.getTypeDeclType(OwnedDecl); 2950 } 2951 2952 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2953 // Can this happen for params? We already checked that they don't conflict 2954 // among each other. Here they can only shadow globals, which is ok. 2955 IdentifierInfo *II = D.getIdentifier(); 2956 if (II) { 2957 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2958 if (PrevDecl->isTemplateParameter()) { 2959 // Maybe we will complain about the shadowed template parameter. 2960 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2961 // Just pretend that we didn't see the previous declaration. 2962 PrevDecl = 0; 2963 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2964 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2965 2966 // Recover by removing the name 2967 II = 0; 2968 D.SetIdentifier(0, D.getIdentifierLoc()); 2969 } 2970 } 2971 } 2972 2973 // Parameters can not be abstract class types. 2974 // For record types, this is done by the AbstractClassUsageDiagnoser once 2975 // the class has been completely parsed. 2976 if (!CurContext->isRecord() && 2977 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2978 diag::err_abstract_type_in_decl, 2979 AbstractParamType)) 2980 D.setInvalidType(true); 2981 2982 QualType T = adjustParameterType(parmDeclType); 2983 2984 ParmVarDecl *New; 2985 if (T == parmDeclType) // parameter type did not need adjustment 2986 New = ParmVarDecl::Create(Context, CurContext, 2987 D.getIdentifierLoc(), II, 2988 parmDeclType, StorageClass, 2989 0); 2990 else // keep track of both the adjusted and unadjusted types 2991 New = OriginalParmVarDecl::Create(Context, CurContext, 2992 D.getIdentifierLoc(), II, T, 2993 parmDeclType, StorageClass, 0); 2994 2995 if (D.isInvalidType()) 2996 New->setInvalidDecl(); 2997 2998 // Parameter declarators cannot be interface types. All ObjC objects are 2999 // passed by reference. 3000 if (T->isObjCInterfaceType()) { 3001 Diag(D.getIdentifierLoc(), 3002 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3003 New->setInvalidDecl(); 3004 } 3005 3006 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3007 if (D.getCXXScopeSpec().isSet()) { 3008 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3009 << D.getCXXScopeSpec().getRange(); 3010 New->setInvalidDecl(); 3011 } 3012 3013 // Add the parameter declaration into this scope. 3014 S->AddDecl(DeclPtrTy::make(New)); 3015 if (II) 3016 IdResolver.AddDecl(New); 3017 3018 ProcessDeclAttributes(S, New, D); 3019 3020 if (New->hasAttr<BlocksAttr>()) { 3021 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3022 } 3023 return DeclPtrTy::make(New); 3024} 3025 3026void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3027 SourceLocation LocAfterDecls) { 3028 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3029 "Not a function declarator!"); 3030 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3031 3032 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3033 // for a K&R function. 3034 if (!FTI.hasPrototype) { 3035 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3036 --i; 3037 if (FTI.ArgInfo[i].Param == 0) { 3038 std::string Code = " int "; 3039 Code += FTI.ArgInfo[i].Ident->getName(); 3040 Code += ";\n"; 3041 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3042 << FTI.ArgInfo[i].Ident 3043 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3044 3045 // Implicitly declare the argument as type 'int' for lack of a better 3046 // type. 3047 DeclSpec DS; 3048 const char* PrevSpec; // unused 3049 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3050 PrevSpec); 3051 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3052 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3053 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3054 } 3055 } 3056 } 3057} 3058 3059Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3060 Declarator &D) { 3061 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3062 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3063 "Not a function declarator!"); 3064 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3065 3066 if (FTI.hasPrototype) { 3067 // FIXME: Diagnose arguments without names in C. 3068 } 3069 3070 Scope *ParentScope = FnBodyScope->getParent(); 3071 3072 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3073 MultiTemplateParamsArg(*this), 3074 /*IsFunctionDefinition=*/true); 3075 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3076} 3077 3078Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3079 if (!D) 3080 return D; 3081 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 3082 3083 CurFunctionNeedsScopeChecking = false; 3084 3085 // See if this is a redefinition. 3086 const FunctionDecl *Definition; 3087 if (FD->getBody(Definition)) { 3088 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3089 Diag(Definition->getLocation(), diag::note_previous_definition); 3090 } 3091 3092 // Builtin functions cannot be defined. 3093 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3094 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3095 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3096 FD->setInvalidDecl(); 3097 } 3098 } 3099 3100 // The return type of a function definition must be complete 3101 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3102 QualType ResultType = FD->getResultType(); 3103 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3104 !FD->isInvalidDecl() && 3105 RequireCompleteType(FD->getLocation(), ResultType, 3106 diag::err_func_def_incomplete_result)) 3107 FD->setInvalidDecl(); 3108 3109 // GNU warning -Wmissing-prototypes: 3110 // Warn if a global function is defined without a previous 3111 // prototype declaration. This warning is issued even if the 3112 // definition itself provides a prototype. The aim is to detect 3113 // global functions that fail to be declared in header files. 3114 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3115 !FD->isMain()) { 3116 bool MissingPrototype = true; 3117 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3118 Prev; Prev = Prev->getPreviousDeclaration()) { 3119 // Ignore any declarations that occur in function or method 3120 // scope, because they aren't visible from the header. 3121 if (Prev->getDeclContext()->isFunctionOrMethod()) 3122 continue; 3123 3124 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3125 break; 3126 } 3127 3128 if (MissingPrototype) 3129 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3130 } 3131 3132 if (FnBodyScope) 3133 PushDeclContext(FnBodyScope, FD); 3134 3135 // Check the validity of our function parameters 3136 CheckParmsForFunctionDef(FD); 3137 3138 // Introduce our parameters into the function scope 3139 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3140 ParmVarDecl *Param = FD->getParamDecl(p); 3141 Param->setOwningFunction(FD); 3142 3143 // If this has an identifier, add it to the scope stack. 3144 if (Param->getIdentifier() && FnBodyScope) 3145 PushOnScopeChains(Param, FnBodyScope); 3146 } 3147 3148 // Checking attributes of current function definition 3149 // dllimport attribute. 3150 if (FD->getAttr<DLLImportAttr>() && 3151 (!FD->getAttr<DLLExportAttr>())) { 3152 // dllimport attribute cannot be applied to definition. 3153 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3154 Diag(FD->getLocation(), 3155 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3156 << "dllimport"; 3157 FD->setInvalidDecl(); 3158 return DeclPtrTy::make(FD); 3159 } else { 3160 // If a symbol previously declared dllimport is later defined, the 3161 // attribute is ignored in subsequent references, and a warning is 3162 // emitted. 3163 Diag(FD->getLocation(), 3164 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3165 << FD->getNameAsCString() << "dllimport"; 3166 } 3167 } 3168 return DeclPtrTy::make(FD); 3169} 3170 3171Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3172 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3173} 3174 3175Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3176 bool IsInstantiation) { 3177 Decl *dcl = D.getAs<Decl>(); 3178 Stmt *Body = BodyArg.takeAs<Stmt>(); 3179 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3180 FD->setBody(Body); 3181 3182 if (!FD->isInvalidDecl()) 3183 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3184 3185 // C++ [basic.def.odr]p2: 3186 // [...] A virtual member function is used if it is not pure. [...] 3187 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3188 if (Method->isVirtual() && !Method->isPure()) 3189 MarkDeclarationReferenced(Method->getLocation(), Method); 3190 3191 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3192 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3193 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3194 MD->setBody(Body); 3195 3196 if (!MD->isInvalidDecl()) 3197 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3198 } else { 3199 Body->Destroy(Context); 3200 return DeclPtrTy(); 3201 } 3202 if (!IsInstantiation) 3203 PopDeclContext(); 3204 3205 // Verify and clean out per-function state. 3206 3207 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3208 3209 // Check goto/label use. 3210 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3211 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3212 LabelStmt *L = I->second; 3213 3214 // Verify that we have no forward references left. If so, there was a goto 3215 // or address of a label taken, but no definition of it. Label fwd 3216 // definitions are indicated with a null substmt. 3217 if (L->getSubStmt() != 0) 3218 continue; 3219 3220 // Emit error. 3221 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3222 3223 // At this point, we have gotos that use the bogus label. Stitch it into 3224 // the function body so that they aren't leaked and that the AST is well 3225 // formed. 3226 if (Body == 0) { 3227 // The whole function wasn't parsed correctly, just delete this. 3228 L->Destroy(Context); 3229 continue; 3230 } 3231 3232 // Otherwise, the body is valid: we want to stitch the label decl into the 3233 // function somewhere so that it is properly owned and so that the goto 3234 // has a valid target. Do this by creating a new compound stmt with the 3235 // label in it. 3236 3237 // Give the label a sub-statement. 3238 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3239 3240 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3241 cast<CXXTryStmt>(Body)->getTryBlock() : 3242 cast<CompoundStmt>(Body); 3243 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3244 Elements.push_back(L); 3245 Compound->setStmts(Context, &Elements[0], Elements.size()); 3246 } 3247 FunctionLabelMap.clear(); 3248 3249 if (!Body) return D; 3250 3251 // Verify that that gotos and switch cases don't jump into scopes illegally. 3252 if (CurFunctionNeedsScopeChecking) 3253 DiagnoseInvalidJumps(Body); 3254 3255 // C++ constructors that have function-try-blocks can't have return statements 3256 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3257 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3258 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3259 3260 return D; 3261} 3262 3263/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3264/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3265NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3266 IdentifierInfo &II, Scope *S) { 3267 // Before we produce a declaration for an implicitly defined 3268 // function, see whether there was a locally-scoped declaration of 3269 // this name as a function or variable. If so, use that 3270 // (non-visible) declaration, and complain about it. 3271 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3272 = LocallyScopedExternalDecls.find(&II); 3273 if (Pos != LocallyScopedExternalDecls.end()) { 3274 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3275 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3276 return Pos->second; 3277 } 3278 3279 // Extension in C99. Legal in C90, but warn about it. 3280 if (getLangOptions().C99) 3281 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3282 else 3283 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3284 3285 // FIXME: handle stuff like: 3286 // void foo() { extern float X(); } 3287 // void bar() { X(); } <-- implicit decl for X in another scope. 3288 3289 // Set a Declarator for the implicit definition: int foo(); 3290 const char *Dummy; 3291 DeclSpec DS; 3292 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3293 Error = Error; // Silence warning. 3294 assert(!Error && "Error setting up implicit decl!"); 3295 Declarator D(DS, Declarator::BlockContext); 3296 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3297 0, 0, false, SourceLocation(), 3298 false, 0,0,0, Loc, D), 3299 SourceLocation()); 3300 D.SetIdentifier(&II, Loc); 3301 3302 // Insert this function into translation-unit scope. 3303 3304 DeclContext *PrevDC = CurContext; 3305 CurContext = Context.getTranslationUnitDecl(); 3306 3307 FunctionDecl *FD = 3308 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3309 FD->setImplicit(); 3310 3311 CurContext = PrevDC; 3312 3313 AddKnownFunctionAttributes(FD); 3314 3315 return FD; 3316} 3317 3318/// \brief Adds any function attributes that we know a priori based on 3319/// the declaration of this function. 3320/// 3321/// These attributes can apply both to implicitly-declared builtins 3322/// (like __builtin___printf_chk) or to library-declared functions 3323/// like NSLog or printf. 3324void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3325 if (FD->isInvalidDecl()) 3326 return; 3327 3328 // If this is a built-in function, map its builtin attributes to 3329 // actual attributes. 3330 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3331 // Handle printf-formatting attributes. 3332 unsigned FormatIdx; 3333 bool HasVAListArg; 3334 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3335 if (!FD->getAttr<FormatAttr>()) 3336 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3337 HasVAListArg ? 0 : FormatIdx + 2)); 3338 } 3339 3340 // Mark const if we don't care about errno and that is the only 3341 // thing preventing the function from being const. This allows 3342 // IRgen to use LLVM intrinsics for such functions. 3343 if (!getLangOptions().MathErrno && 3344 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3345 if (!FD->getAttr<ConstAttr>()) 3346 FD->addAttr(::new (Context) ConstAttr()); 3347 } 3348 } 3349 3350 IdentifierInfo *Name = FD->getIdentifier(); 3351 if (!Name) 3352 return; 3353 if ((!getLangOptions().CPlusPlus && 3354 FD->getDeclContext()->isTranslationUnit()) || 3355 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3356 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3357 LinkageSpecDecl::lang_c)) { 3358 // Okay: this could be a libc/libm/Objective-C function we know 3359 // about. 3360 } else 3361 return; 3362 3363 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3364 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3365 // FIXME: We known better than our headers. 3366 const_cast<FormatAttr *>(Format)->setType("printf"); 3367 } else 3368 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3369 Name->isStr("NSLogv") ? 0 : 2)); 3370 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3371 if (!FD->getAttr<FormatAttr>()) 3372 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3373 Name->isStr("vasprintf") ? 0 : 3)); 3374 } 3375} 3376 3377TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3378 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3379 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3380 3381 // Scope manipulation handled by caller. 3382 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3383 D.getIdentifierLoc(), 3384 D.getIdentifier(), 3385 T); 3386 3387 if (TagType *TT = dyn_cast<TagType>(T)) { 3388 TagDecl *TD = TT->getDecl(); 3389 3390 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3391 // keep track of the TypedefDecl. 3392 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3393 TD->setTypedefForAnonDecl(NewTD); 3394 } 3395 3396 if (D.isInvalidType()) 3397 NewTD->setInvalidDecl(); 3398 return NewTD; 3399} 3400 3401 3402/// \brief Determine whether a tag with a given kind is acceptable 3403/// as a redeclaration of the given tag declaration. 3404/// 3405/// \returns true if the new tag kind is acceptable, false otherwise. 3406bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3407 TagDecl::TagKind NewTag, 3408 SourceLocation NewTagLoc, 3409 const IdentifierInfo &Name) { 3410 // C++ [dcl.type.elab]p3: 3411 // The class-key or enum keyword present in the 3412 // elaborated-type-specifier shall agree in kind with the 3413 // declaration to which the name in theelaborated-type-specifier 3414 // refers. This rule also applies to the form of 3415 // elaborated-type-specifier that declares a class-name or 3416 // friend class since it can be construed as referring to the 3417 // definition of the class. Thus, in any 3418 // elaborated-type-specifier, the enum keyword shall be used to 3419 // refer to an enumeration (7.2), the union class-keyshall be 3420 // used to refer to a union (clause 9), and either the class or 3421 // struct class-key shall be used to refer to a class (clause 9) 3422 // declared using the class or struct class-key. 3423 TagDecl::TagKind OldTag = Previous->getTagKind(); 3424 if (OldTag == NewTag) 3425 return true; 3426 3427 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3428 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3429 // Warn about the struct/class tag mismatch. 3430 bool isTemplate = false; 3431 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3432 isTemplate = Record->getDescribedClassTemplate(); 3433 3434 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3435 << (NewTag == TagDecl::TK_class) 3436 << isTemplate << &Name 3437 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3438 OldTag == TagDecl::TK_class? "class" : "struct"); 3439 Diag(Previous->getLocation(), diag::note_previous_use); 3440 return true; 3441 } 3442 return false; 3443} 3444 3445/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3446/// former case, Name will be non-null. In the later case, Name will be null. 3447/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3448/// reference/declaration/definition of a tag. 3449Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3450 SourceLocation KWLoc, const CXXScopeSpec &SS, 3451 IdentifierInfo *Name, SourceLocation NameLoc, 3452 AttributeList *Attr, AccessSpecifier AS, 3453 bool &OwnedDecl) { 3454 // If this is not a definition, it must have a name. 3455 assert((Name != 0 || TK == TK_Definition) && 3456 "Nameless record must be a definition!"); 3457 3458 OwnedDecl = false; 3459 TagDecl::TagKind Kind; 3460 switch (TagSpec) { 3461 default: assert(0 && "Unknown tag type!"); 3462 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3463 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3464 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3465 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3466 } 3467 3468 DeclContext *SearchDC = CurContext; 3469 DeclContext *DC = CurContext; 3470 NamedDecl *PrevDecl = 0; 3471 3472 bool Invalid = false; 3473 3474 if (Name && SS.isNotEmpty()) { 3475 // We have a nested-name tag ('struct foo::bar'). 3476 3477 // Check for invalid 'foo::'. 3478 if (SS.isInvalid()) { 3479 Name = 0; 3480 goto CreateNewDecl; 3481 } 3482 3483 if (RequireCompleteDeclContext(SS)) 3484 return DeclPtrTy::make((Decl *)0); 3485 3486 DC = computeDeclContext(SS); 3487 SearchDC = DC; 3488 // Look-up name inside 'foo::'. 3489 PrevDecl 3490 = dyn_cast_or_null<TagDecl>( 3491 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3492 3493 // A tag 'foo::bar' must already exist. 3494 if (PrevDecl == 0) { 3495 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3496 Name = 0; 3497 Invalid = true; 3498 goto CreateNewDecl; 3499 } 3500 } else if (Name) { 3501 // If this is a named struct, check to see if there was a previous forward 3502 // declaration or definition. 3503 // FIXME: We're looking into outer scopes here, even when we 3504 // shouldn't be. Doing so can result in ambiguities that we 3505 // shouldn't be diagnosing. 3506 LookupResult R = LookupName(S, Name, LookupTagName, 3507 /*RedeclarationOnly=*/(TK != TK_Reference)); 3508 if (R.isAmbiguous()) { 3509 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3510 // FIXME: This is not best way to recover from case like: 3511 // 3512 // struct S s; 3513 // 3514 // causes needless "incomplete type" error later. 3515 Name = 0; 3516 PrevDecl = 0; 3517 Invalid = true; 3518 } 3519 else 3520 PrevDecl = R; 3521 3522 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3523 // FIXME: This makes sure that we ignore the contexts associated 3524 // with C structs, unions, and enums when looking for a matching 3525 // tag declaration or definition. See the similar lookup tweak 3526 // in Sema::LookupName; is there a better way to deal with this? 3527 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3528 SearchDC = SearchDC->getParent(); 3529 } 3530 } 3531 3532 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3533 // Maybe we will complain about the shadowed template parameter. 3534 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3535 // Just pretend that we didn't see the previous declaration. 3536 PrevDecl = 0; 3537 } 3538 3539 if (PrevDecl) { 3540 // Check whether the previous declaration is usable. 3541 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3542 3543 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3544 // If this is a use of a previous tag, or if the tag is already declared 3545 // in the same scope (so that the definition/declaration completes or 3546 // rementions the tag), reuse the decl. 3547 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3548 // Make sure that this wasn't declared as an enum and now used as a 3549 // struct or something similar. 3550 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3551 bool SafeToContinue 3552 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3553 Kind != TagDecl::TK_enum); 3554 if (SafeToContinue) 3555 Diag(KWLoc, diag::err_use_with_wrong_tag) 3556 << Name 3557 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3558 PrevTagDecl->getKindName()); 3559 else 3560 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3561 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3562 3563 if (SafeToContinue) 3564 Kind = PrevTagDecl->getTagKind(); 3565 else { 3566 // Recover by making this an anonymous redefinition. 3567 Name = 0; 3568 PrevDecl = 0; 3569 Invalid = true; 3570 } 3571 } 3572 3573 if (!Invalid) { 3574 // If this is a use, just return the declaration we found. 3575 3576 // FIXME: In the future, return a variant or some other clue 3577 // for the consumer of this Decl to know it doesn't own it. 3578 // For our current ASTs this shouldn't be a problem, but will 3579 // need to be changed with DeclGroups. 3580 if (TK == TK_Reference) 3581 return DeclPtrTy::make(PrevDecl); 3582 3583 // Diagnose attempts to redefine a tag. 3584 if (TK == TK_Definition) { 3585 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3586 Diag(NameLoc, diag::err_redefinition) << Name; 3587 Diag(Def->getLocation(), diag::note_previous_definition); 3588 // If this is a redefinition, recover by making this 3589 // struct be anonymous, which will make any later 3590 // references get the previous definition. 3591 Name = 0; 3592 PrevDecl = 0; 3593 Invalid = true; 3594 } else { 3595 // If the type is currently being defined, complain 3596 // about a nested redefinition. 3597 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3598 if (Tag->isBeingDefined()) { 3599 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3600 Diag(PrevTagDecl->getLocation(), 3601 diag::note_previous_definition); 3602 Name = 0; 3603 PrevDecl = 0; 3604 Invalid = true; 3605 } 3606 } 3607 3608 // Okay, this is definition of a previously declared or referenced 3609 // tag PrevDecl. We're going to create a new Decl for it. 3610 } 3611 } 3612 // If we get here we have (another) forward declaration or we 3613 // have a definition. Just create a new decl. 3614 } else { 3615 // If we get here, this is a definition of a new tag type in a nested 3616 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3617 // new decl/type. We set PrevDecl to NULL so that the entities 3618 // have distinct types. 3619 PrevDecl = 0; 3620 } 3621 // If we get here, we're going to create a new Decl. If PrevDecl 3622 // is non-NULL, it's a definition of the tag declared by 3623 // PrevDecl. If it's NULL, we have a new definition. 3624 } else { 3625 // PrevDecl is a namespace, template, or anything else 3626 // that lives in the IDNS_Tag identifier namespace. 3627 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3628 // The tag name clashes with a namespace name, issue an error and 3629 // recover by making this tag be anonymous. 3630 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3631 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3632 Name = 0; 3633 PrevDecl = 0; 3634 Invalid = true; 3635 } else { 3636 // The existing declaration isn't relevant to us; we're in a 3637 // new scope, so clear out the previous declaration. 3638 PrevDecl = 0; 3639 } 3640 } 3641 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3642 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3643 // C++ [basic.scope.pdecl]p5: 3644 // -- for an elaborated-type-specifier of the form 3645 // 3646 // class-key identifier 3647 // 3648 // if the elaborated-type-specifier is used in the 3649 // decl-specifier-seq or parameter-declaration-clause of a 3650 // function defined in namespace scope, the identifier is 3651 // declared as a class-name in the namespace that contains 3652 // the declaration; otherwise, except as a friend 3653 // declaration, the identifier is declared in the smallest 3654 // non-class, non-function-prototype scope that contains the 3655 // declaration. 3656 // 3657 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3658 // C structs and unions. 3659 // 3660 // GNU C also supports this behavior as part of its incomplete 3661 // enum types extension, while GNU C++ does not. 3662 // 3663 // Find the context where we'll be declaring the tag. 3664 // FIXME: We would like to maintain the current DeclContext as the 3665 // lexical context, 3666 while (SearchDC->isRecord()) 3667 SearchDC = SearchDC->getParent(); 3668 3669 // Find the scope where we'll be declaring the tag. 3670 while (S->isClassScope() || 3671 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3672 ((S->getFlags() & Scope::DeclScope) == 0) || 3673 (S->getEntity() && 3674 ((DeclContext *)S->getEntity())->isTransparentContext())) 3675 S = S->getParent(); 3676 } 3677 3678CreateNewDecl: 3679 3680 // If there is an identifier, use the location of the identifier as the 3681 // location of the decl, otherwise use the location of the struct/union 3682 // keyword. 3683 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3684 3685 // Otherwise, create a new declaration. If there is a previous 3686 // declaration of the same entity, the two will be linked via 3687 // PrevDecl. 3688 TagDecl *New; 3689 3690 if (Kind == TagDecl::TK_enum) { 3691 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3692 // enum X { A, B, C } D; D should chain to X. 3693 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3694 cast_or_null<EnumDecl>(PrevDecl)); 3695 // If this is an undefined enum, warn. 3696 if (TK != TK_Definition && !Invalid) { 3697 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3698 : diag::ext_forward_ref_enum; 3699 Diag(Loc, DK); 3700 } 3701 } else { 3702 // struct/union/class 3703 3704 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3705 // struct X { int A; } D; D should chain to X. 3706 if (getLangOptions().CPlusPlus) 3707 // FIXME: Look for a way to use RecordDecl for simple structs. 3708 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3709 cast_or_null<CXXRecordDecl>(PrevDecl)); 3710 else 3711 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3712 cast_or_null<RecordDecl>(PrevDecl)); 3713 } 3714 3715 if (Kind != TagDecl::TK_enum) { 3716 // Handle #pragma pack: if the #pragma pack stack has non-default 3717 // alignment, make up a packed attribute for this decl. These 3718 // attributes are checked when the ASTContext lays out the 3719 // structure. 3720 // 3721 // It is important for implementing the correct semantics that this 3722 // happen here (in act on tag decl). The #pragma pack stack is 3723 // maintained as a result of parser callbacks which can occur at 3724 // many points during the parsing of a struct declaration (because 3725 // the #pragma tokens are effectively skipped over during the 3726 // parsing of the struct). 3727 if (unsigned Alignment = getPragmaPackAlignment()) 3728 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3729 } 3730 3731 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3732 // C++ [dcl.typedef]p3: 3733 // [...] Similarly, in a given scope, a class or enumeration 3734 // shall not be declared with the same name as a typedef-name 3735 // that is declared in that scope and refers to a type other 3736 // than the class or enumeration itself. 3737 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3738 TypedefDecl *PrevTypedef = 0; 3739 if (Lookup.getKind() == LookupResult::Found) 3740 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3741 3742 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3743 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3744 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3745 Diag(Loc, diag::err_tag_definition_of_typedef) 3746 << Context.getTypeDeclType(New) 3747 << PrevTypedef->getUnderlyingType(); 3748 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3749 Invalid = true; 3750 } 3751 } 3752 3753 if (Invalid) 3754 New->setInvalidDecl(); 3755 3756 if (Attr) 3757 ProcessDeclAttributeList(S, New, Attr); 3758 3759 // If we're declaring or defining a tag in function prototype scope 3760 // in C, note that this type can only be used within the function. 3761 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3762 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3763 3764 // Set the lexical context. If the tag has a C++ scope specifier, the 3765 // lexical context will be different from the semantic context. 3766 New->setLexicalDeclContext(CurContext); 3767 3768 // Set the access specifier. 3769 if (!Invalid) 3770 SetMemberAccessSpecifier(New, PrevDecl, AS); 3771 3772 if (TK == TK_Definition) 3773 New->startDefinition(); 3774 3775 // If this has an identifier, add it to the scope stack. 3776 if (Name) { 3777 S = getNonFieldDeclScope(S); 3778 PushOnScopeChains(New, S); 3779 } else { 3780 CurContext->addDecl(New); 3781 } 3782 3783 // If this is the C FILE type, notify the AST context. 3784 if (IdentifierInfo *II = New->getIdentifier()) 3785 if (!New->isInvalidDecl() && 3786 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 3787 II->isStr("FILE")) 3788 Context.setFILEDecl(New); 3789 3790 OwnedDecl = true; 3791 return DeclPtrTy::make(New); 3792} 3793 3794void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3795 AdjustDeclIfTemplate(TagD); 3796 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3797 3798 // Enter the tag context. 3799 PushDeclContext(S, Tag); 3800 3801 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3802 FieldCollector->StartClass(); 3803 3804 if (Record->getIdentifier()) { 3805 // C++ [class]p2: 3806 // [...] The class-name is also inserted into the scope of the 3807 // class itself; this is known as the injected-class-name. For 3808 // purposes of access checking, the injected-class-name is treated 3809 // as if it were a public member name. 3810 CXXRecordDecl *InjectedClassName 3811 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3812 CurContext, Record->getLocation(), 3813 Record->getIdentifier(), Record); 3814 InjectedClassName->setImplicit(); 3815 InjectedClassName->setAccess(AS_public); 3816 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3817 InjectedClassName->setDescribedClassTemplate(Template); 3818 PushOnScopeChains(InjectedClassName, S); 3819 assert(InjectedClassName->isInjectedClassName() && 3820 "Broken injected-class-name"); 3821 } 3822 } 3823} 3824 3825void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3826 AdjustDeclIfTemplate(TagD); 3827 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3828 3829 if (isa<CXXRecordDecl>(Tag)) 3830 FieldCollector->FinishClass(); 3831 3832 // Exit this scope of this tag's definition. 3833 PopDeclContext(); 3834 3835 // Notify the consumer that we've defined a tag. 3836 Consumer.HandleTagDeclDefinition(Tag); 3837} 3838 3839// Note that FieldName may be null for anonymous bitfields. 3840bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3841 QualType FieldTy, const Expr *BitWidth) { 3842 3843 // C99 6.7.2.1p4 - verify the field type. 3844 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3845 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3846 // Handle incomplete types with specific error. 3847 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3848 return true; 3849 if (FieldName) 3850 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3851 << FieldName << FieldTy << BitWidth->getSourceRange(); 3852 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3853 << FieldTy << BitWidth->getSourceRange(); 3854 } 3855 3856 // If the bit-width is type- or value-dependent, don't try to check 3857 // it now. 3858 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3859 return false; 3860 3861 llvm::APSInt Value; 3862 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3863 return true; 3864 3865 // Zero-width bitfield is ok for anonymous field. 3866 if (Value == 0 && FieldName) 3867 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3868 3869 if (Value.isSigned() && Value.isNegative()) { 3870 if (FieldName) 3871 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3872 << FieldName << Value.toString(10); 3873 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3874 << Value.toString(10); 3875 } 3876 3877 if (!FieldTy->isDependentType()) { 3878 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3879 if (Value.getZExtValue() > TypeSize) { 3880 if (FieldName) 3881 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3882 << FieldName << (unsigned)TypeSize; 3883 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3884 << (unsigned)TypeSize; 3885 } 3886 } 3887 3888 return false; 3889} 3890 3891/// ActOnField - Each field of a struct/union/class is passed into this in order 3892/// to create a FieldDecl object for it. 3893Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3894 SourceLocation DeclStart, 3895 Declarator &D, ExprTy *BitfieldWidth) { 3896 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3897 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3898 AS_public); 3899 return DeclPtrTy::make(Res); 3900} 3901 3902/// HandleField - Analyze a field of a C struct or a C++ data member. 3903/// 3904FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3905 SourceLocation DeclStart, 3906 Declarator &D, Expr *BitWidth, 3907 AccessSpecifier AS) { 3908 IdentifierInfo *II = D.getIdentifier(); 3909 SourceLocation Loc = DeclStart; 3910 if (II) Loc = D.getIdentifierLoc(); 3911 3912 QualType T = GetTypeForDeclarator(D, S); 3913 if (getLangOptions().CPlusPlus) 3914 CheckExtraCXXDefaultArguments(D); 3915 3916 DiagnoseFunctionSpecifiers(D); 3917 3918 if (D.getDeclSpec().isThreadSpecified()) 3919 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3920 3921 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3922 3923 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3924 // Maybe we will complain about the shadowed template parameter. 3925 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3926 // Just pretend that we didn't see the previous declaration. 3927 PrevDecl = 0; 3928 } 3929 3930 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3931 PrevDecl = 0; 3932 3933 FieldDecl *NewFD 3934 = CheckFieldDecl(II, T, Record, Loc, 3935 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3936 BitWidth, AS, PrevDecl, &D); 3937 if (NewFD->isInvalidDecl() && PrevDecl) { 3938 // Don't introduce NewFD into scope; there's already something 3939 // with the same name in the same scope. 3940 } else if (II) { 3941 PushOnScopeChains(NewFD, S); 3942 } else 3943 Record->addDecl(NewFD); 3944 3945 return NewFD; 3946} 3947 3948/// \brief Build a new FieldDecl and check its well-formedness. 3949/// 3950/// This routine builds a new FieldDecl given the fields name, type, 3951/// record, etc. \p PrevDecl should refer to any previous declaration 3952/// with the same name and in the same scope as the field to be 3953/// created. 3954/// 3955/// \returns a new FieldDecl. 3956/// 3957/// \todo The Declarator argument is a hack. It will be removed once 3958FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3959 RecordDecl *Record, SourceLocation Loc, 3960 bool Mutable, Expr *BitWidth, 3961 AccessSpecifier AS, NamedDecl *PrevDecl, 3962 Declarator *D) { 3963 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3964 bool InvalidDecl = false; 3965 if (D) InvalidDecl = D->isInvalidType(); 3966 3967 // If we receive a broken type, recover by assuming 'int' and 3968 // marking this declaration as invalid. 3969 if (T.isNull()) { 3970 InvalidDecl = true; 3971 T = Context.IntTy; 3972 } 3973 3974 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3975 // than a variably modified type. 3976 if (T->isVariablyModifiedType()) { 3977 bool SizeIsNegative; 3978 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3979 SizeIsNegative); 3980 if (!FixedTy.isNull()) { 3981 Diag(Loc, diag::warn_illegal_constant_array_size); 3982 T = FixedTy; 3983 } else { 3984 if (SizeIsNegative) 3985 Diag(Loc, diag::err_typecheck_negative_array_size); 3986 else 3987 Diag(Loc, diag::err_typecheck_field_variable_size); 3988 T = Context.IntTy; 3989 InvalidDecl = true; 3990 } 3991 } 3992 3993 // Fields can not have abstract class types 3994 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3995 AbstractFieldType)) 3996 InvalidDecl = true; 3997 3998 // If this is declared as a bit-field, check the bit-field. 3999 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 4000 InvalidDecl = true; 4001 DeleteExpr(BitWidth); 4002 BitWidth = 0; 4003 } 4004 4005 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 4006 Mutable); 4007 if (InvalidDecl) 4008 NewFD->setInvalidDecl(); 4009 4010 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4011 Diag(Loc, diag::err_duplicate_member) << II; 4012 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4013 NewFD->setInvalidDecl(); 4014 } 4015 4016 if (getLangOptions().CPlusPlus && !T->isPODType()) 4017 cast<CXXRecordDecl>(Record)->setPOD(false); 4018 4019 // FIXME: We need to pass in the attributes given an AST 4020 // representation, not a parser representation. 4021 if (D) 4022 // FIXME: What to pass instead of TUScope? 4023 ProcessDeclAttributes(TUScope, NewFD, *D); 4024 4025 if (T.isObjCGCWeak()) 4026 Diag(Loc, diag::warn_attribute_weak_on_field); 4027 4028 NewFD->setAccess(AS); 4029 4030 // C++ [dcl.init.aggr]p1: 4031 // An aggregate is an array or a class (clause 9) with [...] no 4032 // private or protected non-static data members (clause 11). 4033 // A POD must be an aggregate. 4034 if (getLangOptions().CPlusPlus && 4035 (AS == AS_private || AS == AS_protected)) { 4036 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4037 CXXRecord->setAggregate(false); 4038 CXXRecord->setPOD(false); 4039 } 4040 4041 return NewFD; 4042} 4043 4044/// TranslateIvarVisibility - Translate visibility from a token ID to an 4045/// AST enum value. 4046static ObjCIvarDecl::AccessControl 4047TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4048 switch (ivarVisibility) { 4049 default: assert(0 && "Unknown visitibility kind"); 4050 case tok::objc_private: return ObjCIvarDecl::Private; 4051 case tok::objc_public: return ObjCIvarDecl::Public; 4052 case tok::objc_protected: return ObjCIvarDecl::Protected; 4053 case tok::objc_package: return ObjCIvarDecl::Package; 4054 } 4055} 4056 4057/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4058/// in order to create an IvarDecl object for it. 4059Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4060 SourceLocation DeclStart, 4061 DeclPtrTy IntfDecl, 4062 Declarator &D, ExprTy *BitfieldWidth, 4063 tok::ObjCKeywordKind Visibility) { 4064 4065 IdentifierInfo *II = D.getIdentifier(); 4066 Expr *BitWidth = (Expr*)BitfieldWidth; 4067 SourceLocation Loc = DeclStart; 4068 if (II) Loc = D.getIdentifierLoc(); 4069 4070 // FIXME: Unnamed fields can be handled in various different ways, for 4071 // example, unnamed unions inject all members into the struct namespace! 4072 4073 QualType T = GetTypeForDeclarator(D, S); 4074 4075 if (BitWidth) { 4076 // 6.7.2.1p3, 6.7.2.1p4 4077 if (VerifyBitField(Loc, II, T, BitWidth)) { 4078 D.setInvalidType(); 4079 DeleteExpr(BitWidth); 4080 BitWidth = 0; 4081 } 4082 } else { 4083 // Not a bitfield. 4084 4085 // validate II. 4086 4087 } 4088 4089 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4090 // than a variably modified type. 4091 if (T->isVariablyModifiedType()) { 4092 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4093 D.setInvalidType(); 4094 } 4095 4096 // Get the visibility (access control) for this ivar. 4097 ObjCIvarDecl::AccessControl ac = 4098 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4099 : ObjCIvarDecl::None; 4100 // Must set ivar's DeclContext to its enclosing interface. 4101 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4102 DeclContext *EnclosingContext; 4103 if (ObjCImplementationDecl *IMPDecl = 4104 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4105 // Case of ivar declared in an implementation. Context is that of its class. 4106 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4107 assert(IDecl && "No class- ActOnIvar"); 4108 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4109 } 4110 else 4111 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4112 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4113 4114 // Construct the decl. 4115 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4116 EnclosingContext, Loc, II, T,ac, 4117 (Expr *)BitfieldWidth); 4118 4119 if (II) { 4120 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4121 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4122 && !isa<TagDecl>(PrevDecl)) { 4123 Diag(Loc, diag::err_duplicate_member) << II; 4124 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4125 NewID->setInvalidDecl(); 4126 } 4127 } 4128 4129 // Process attributes attached to the ivar. 4130 ProcessDeclAttributes(S, NewID, D); 4131 4132 if (D.isInvalidType()) 4133 NewID->setInvalidDecl(); 4134 4135 if (II) { 4136 // FIXME: When interfaces are DeclContexts, we'll need to add 4137 // these to the interface. 4138 S->AddDecl(DeclPtrTy::make(NewID)); 4139 IdResolver.AddDecl(NewID); 4140 } 4141 4142 return DeclPtrTy::make(NewID); 4143} 4144 4145void Sema::ActOnFields(Scope* S, 4146 SourceLocation RecLoc, DeclPtrTy RecDecl, 4147 DeclPtrTy *Fields, unsigned NumFields, 4148 SourceLocation LBrac, SourceLocation RBrac, 4149 AttributeList *Attr) { 4150 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4151 assert(EnclosingDecl && "missing record or interface decl"); 4152 4153 // If the decl this is being inserted into is invalid, then it may be a 4154 // redeclaration or some other bogus case. Don't try to add fields to it. 4155 if (EnclosingDecl->isInvalidDecl()) { 4156 // FIXME: Deallocate fields? 4157 return; 4158 } 4159 4160 4161 // Verify that all the fields are okay. 4162 unsigned NumNamedMembers = 0; 4163 llvm::SmallVector<FieldDecl*, 32> RecFields; 4164 4165 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4166 for (unsigned i = 0; i != NumFields; ++i) { 4167 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4168 4169 // Get the type for the field. 4170 Type *FDTy = FD->getType().getTypePtr(); 4171 4172 if (!FD->isAnonymousStructOrUnion()) { 4173 // Remember all fields written by the user. 4174 RecFields.push_back(FD); 4175 } 4176 4177 // If the field is already invalid for some reason, don't emit more 4178 // diagnostics about it. 4179 if (FD->isInvalidDecl()) 4180 continue; 4181 4182 // C99 6.7.2.1p2: 4183 // A structure or union shall not contain a member with 4184 // incomplete or function type (hence, a structure shall not 4185 // contain an instance of itself, but may contain a pointer to 4186 // an instance of itself), except that the last member of a 4187 // structure with more than one named member may have incomplete 4188 // array type; such a structure (and any union containing, 4189 // possibly recursively, a member that is such a structure) 4190 // shall not be a member of a structure or an element of an 4191 // array. 4192 if (FDTy->isFunctionType()) { 4193 // Field declared as a function. 4194 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4195 << FD->getDeclName(); 4196 FD->setInvalidDecl(); 4197 EnclosingDecl->setInvalidDecl(); 4198 continue; 4199 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4200 Record && Record->isStruct()) { 4201 // Flexible array member. 4202 if (NumNamedMembers < 1) { 4203 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4204 << FD->getDeclName(); 4205 FD->setInvalidDecl(); 4206 EnclosingDecl->setInvalidDecl(); 4207 continue; 4208 } 4209 // Okay, we have a legal flexible array member at the end of the struct. 4210 if (Record) 4211 Record->setHasFlexibleArrayMember(true); 4212 } else if (!FDTy->isDependentType() && 4213 RequireCompleteType(FD->getLocation(), FD->getType(), 4214 diag::err_field_incomplete)) { 4215 // Incomplete type 4216 FD->setInvalidDecl(); 4217 EnclosingDecl->setInvalidDecl(); 4218 continue; 4219 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4220 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4221 // If this is a member of a union, then entire union becomes "flexible". 4222 if (Record && Record->isUnion()) { 4223 Record->setHasFlexibleArrayMember(true); 4224 } else { 4225 // If this is a struct/class and this is not the last element, reject 4226 // it. Note that GCC supports variable sized arrays in the middle of 4227 // structures. 4228 if (i != NumFields-1) 4229 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4230 << FD->getDeclName() << FD->getType(); 4231 else { 4232 // We support flexible arrays at the end of structs in 4233 // other structs as an extension. 4234 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4235 << FD->getDeclName(); 4236 if (Record) 4237 Record->setHasFlexibleArrayMember(true); 4238 } 4239 } 4240 } 4241 } else if (FDTy->isObjCInterfaceType()) { 4242 /// A field cannot be an Objective-c object 4243 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4244 FD->setInvalidDecl(); 4245 EnclosingDecl->setInvalidDecl(); 4246 continue; 4247 } 4248 // Keep track of the number of named members. 4249 if (FD->getIdentifier()) 4250 ++NumNamedMembers; 4251 } 4252 4253 // Okay, we successfully defined 'Record'. 4254 if (Record) { 4255 Record->completeDefinition(Context); 4256 } else { 4257 ObjCIvarDecl **ClsFields = 4258 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4259 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4260 ID->setIVarList(ClsFields, RecFields.size(), Context); 4261 ID->setLocEnd(RBrac); 4262 // Add ivar's to class's DeclContext. 4263 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4264 ClsFields[i]->setLexicalDeclContext(ID); 4265 ID->addDecl(ClsFields[i]); 4266 } 4267 // Must enforce the rule that ivars in the base classes may not be 4268 // duplicates. 4269 if (ID->getSuperClass()) { 4270 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4271 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4272 ObjCIvarDecl* Ivar = (*IVI); 4273 4274 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4275 ObjCIvarDecl* prevIvar = 4276 ID->getSuperClass()->lookupInstanceVariable(II); 4277 if (prevIvar) { 4278 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4279 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4280 } 4281 } 4282 } 4283 } 4284 } else if (ObjCImplementationDecl *IMPDecl = 4285 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4286 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4287 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4288 // Ivar declared in @implementation never belongs to the implementation. 4289 // Only it is in implementation's lexical context. 4290 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4291 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4292 } 4293 } 4294 4295 if (Attr) 4296 ProcessDeclAttributeList(S, Record, Attr); 4297} 4298 4299EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4300 EnumConstantDecl *LastEnumConst, 4301 SourceLocation IdLoc, 4302 IdentifierInfo *Id, 4303 ExprArg val) { 4304 Expr *Val = (Expr *)val.get(); 4305 4306 llvm::APSInt EnumVal(32); 4307 QualType EltTy; 4308 if (Val && !Val->isTypeDependent()) { 4309 // Make sure to promote the operand type to int. 4310 UsualUnaryConversions(Val); 4311 if (Val != val.get()) { 4312 val.release(); 4313 val = Val; 4314 } 4315 4316 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4317 SourceLocation ExpLoc; 4318 if (!Val->isValueDependent() && 4319 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4320 Val = 0; 4321 } else { 4322 EltTy = Val->getType(); 4323 } 4324 } 4325 4326 if (!Val) { 4327 if (LastEnumConst) { 4328 // Assign the last value + 1. 4329 EnumVal = LastEnumConst->getInitVal(); 4330 ++EnumVal; 4331 4332 // Check for overflow on increment. 4333 if (EnumVal < LastEnumConst->getInitVal()) 4334 Diag(IdLoc, diag::warn_enum_value_overflow); 4335 4336 EltTy = LastEnumConst->getType(); 4337 } else { 4338 // First value, set to zero. 4339 EltTy = Context.IntTy; 4340 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4341 } 4342 } 4343 4344 val.release(); 4345 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4346 Val, EnumVal); 4347} 4348 4349 4350Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4351 DeclPtrTy lastEnumConst, 4352 SourceLocation IdLoc, 4353 IdentifierInfo *Id, 4354 SourceLocation EqualLoc, ExprTy *val) { 4355 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4356 EnumConstantDecl *LastEnumConst = 4357 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4358 Expr *Val = static_cast<Expr*>(val); 4359 4360 // The scope passed in may not be a decl scope. Zip up the scope tree until 4361 // we find one that is. 4362 S = getNonFieldDeclScope(S); 4363 4364 // Verify that there isn't already something declared with this name in this 4365 // scope. 4366 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4367 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4368 // Maybe we will complain about the shadowed template parameter. 4369 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4370 // Just pretend that we didn't see the previous declaration. 4371 PrevDecl = 0; 4372 } 4373 4374 if (PrevDecl) { 4375 // When in C++, we may get a TagDecl with the same name; in this case the 4376 // enum constant will 'hide' the tag. 4377 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4378 "Received TagDecl when not in C++!"); 4379 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4380 if (isa<EnumConstantDecl>(PrevDecl)) 4381 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4382 else 4383 Diag(IdLoc, diag::err_redefinition) << Id; 4384 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4385 if (Val) Val->Destroy(Context); 4386 return DeclPtrTy(); 4387 } 4388 } 4389 4390 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4391 IdLoc, Id, Owned(Val)); 4392 4393 // Register this decl in the current scope stack. 4394 if (New) 4395 PushOnScopeChains(New, S); 4396 4397 return DeclPtrTy::make(New); 4398} 4399 4400void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 4401 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 4402 DeclPtrTy *Elements, unsigned NumElements) { 4403 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4404 QualType EnumType = Context.getTypeDeclType(Enum); 4405 4406 // TODO: If the result value doesn't fit in an int, it must be a long or long 4407 // long value. ISO C does not support this, but GCC does as an extension, 4408 // emit a warning. 4409 unsigned IntWidth = Context.Target.getIntWidth(); 4410 4411 // Verify that all the values are okay, compute the size of the values, and 4412 // reverse the list. 4413 unsigned NumNegativeBits = 0; 4414 unsigned NumPositiveBits = 0; 4415 4416 // Keep track of whether all elements have type int. 4417 bool AllElementsInt = true; 4418 4419 for (unsigned i = 0; i != NumElements; ++i) { 4420 EnumConstantDecl *ECD = 4421 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4422 if (!ECD) continue; // Already issued a diagnostic. 4423 4424 // If the enum value doesn't fit in an int, emit an extension warning. 4425 const llvm::APSInt &InitVal = ECD->getInitVal(); 4426 assert(InitVal.getBitWidth() >= IntWidth && 4427 "Should have promoted value to int"); 4428 if (InitVal.getBitWidth() > IntWidth) { 4429 llvm::APSInt V(InitVal); 4430 V.trunc(IntWidth); 4431 V.extend(InitVal.getBitWidth()); 4432 if (V != InitVal) 4433 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4434 << InitVal.toString(10); 4435 } 4436 4437 // Keep track of the size of positive and negative values. 4438 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4439 NumPositiveBits = std::max(NumPositiveBits, 4440 (unsigned)InitVal.getActiveBits()); 4441 else 4442 NumNegativeBits = std::max(NumNegativeBits, 4443 (unsigned)InitVal.getMinSignedBits()); 4444 4445 // Keep track of whether every enum element has type int (very commmon). 4446 if (AllElementsInt) 4447 AllElementsInt = ECD->getType() == Context.IntTy; 4448 } 4449 4450 // Figure out the type that should be used for this enum. 4451 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4452 QualType BestType; 4453 unsigned BestWidth; 4454 4455 if (NumNegativeBits) { 4456 // If there is a negative value, figure out the smallest integer type (of 4457 // int/long/longlong) that fits. 4458 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4459 BestType = Context.IntTy; 4460 BestWidth = IntWidth; 4461 } else { 4462 BestWidth = Context.Target.getLongWidth(); 4463 4464 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4465 BestType = Context.LongTy; 4466 else { 4467 BestWidth = Context.Target.getLongLongWidth(); 4468 4469 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4470 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4471 BestType = Context.LongLongTy; 4472 } 4473 } 4474 } else { 4475 // If there is no negative value, figure out which of uint, ulong, ulonglong 4476 // fits. 4477 if (NumPositiveBits <= IntWidth) { 4478 BestType = Context.UnsignedIntTy; 4479 BestWidth = IntWidth; 4480 } else if (NumPositiveBits <= 4481 (BestWidth = Context.Target.getLongWidth())) { 4482 BestType = Context.UnsignedLongTy; 4483 } else { 4484 BestWidth = Context.Target.getLongLongWidth(); 4485 assert(NumPositiveBits <= BestWidth && 4486 "How could an initializer get larger than ULL?"); 4487 BestType = Context.UnsignedLongLongTy; 4488 } 4489 } 4490 4491 // Loop over all of the enumerator constants, changing their types to match 4492 // the type of the enum if needed. 4493 for (unsigned i = 0; i != NumElements; ++i) { 4494 EnumConstantDecl *ECD = 4495 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4496 if (!ECD) continue; // Already issued a diagnostic. 4497 4498 // Standard C says the enumerators have int type, but we allow, as an 4499 // extension, the enumerators to be larger than int size. If each 4500 // enumerator value fits in an int, type it as an int, otherwise type it the 4501 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4502 // that X has type 'int', not 'unsigned'. 4503 if (ECD->getType() == Context.IntTy) { 4504 // Make sure the init value is signed. 4505 llvm::APSInt IV = ECD->getInitVal(); 4506 IV.setIsSigned(true); 4507 ECD->setInitVal(IV); 4508 4509 if (getLangOptions().CPlusPlus) 4510 // C++ [dcl.enum]p4: Following the closing brace of an 4511 // enum-specifier, each enumerator has the type of its 4512 // enumeration. 4513 ECD->setType(EnumType); 4514 continue; // Already int type. 4515 } 4516 4517 // Determine whether the value fits into an int. 4518 llvm::APSInt InitVal = ECD->getInitVal(); 4519 bool FitsInInt; 4520 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4521 FitsInInt = InitVal.getActiveBits() < IntWidth; 4522 else 4523 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4524 4525 // If it fits into an integer type, force it. Otherwise force it to match 4526 // the enum decl type. 4527 QualType NewTy; 4528 unsigned NewWidth; 4529 bool NewSign; 4530 if (FitsInInt) { 4531 NewTy = Context.IntTy; 4532 NewWidth = IntWidth; 4533 NewSign = true; 4534 } else if (ECD->getType() == BestType) { 4535 // Already the right type! 4536 if (getLangOptions().CPlusPlus) 4537 // C++ [dcl.enum]p4: Following the closing brace of an 4538 // enum-specifier, each enumerator has the type of its 4539 // enumeration. 4540 ECD->setType(EnumType); 4541 continue; 4542 } else { 4543 NewTy = BestType; 4544 NewWidth = BestWidth; 4545 NewSign = BestType->isSignedIntegerType(); 4546 } 4547 4548 // Adjust the APSInt value. 4549 InitVal.extOrTrunc(NewWidth); 4550 InitVal.setIsSigned(NewSign); 4551 ECD->setInitVal(InitVal); 4552 4553 // Adjust the Expr initializer and type. 4554 if (ECD->getInitExpr()) 4555 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4556 /*isLvalue=*/false)); 4557 if (getLangOptions().CPlusPlus) 4558 // C++ [dcl.enum]p4: Following the closing brace of an 4559 // enum-specifier, each enumerator has the type of its 4560 // enumeration. 4561 ECD->setType(EnumType); 4562 else 4563 ECD->setType(NewTy); 4564 } 4565 4566 Enum->completeDefinition(Context, BestType); 4567} 4568 4569Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4570 ExprArg expr) { 4571 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4572 4573 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 4574 Loc, AsmString); 4575 CurContext->addDecl(New); 4576 return DeclPtrTy::make(New); 4577} 4578 4579void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 4580 SourceLocation PragmaLoc, 4581 SourceLocation NameLoc) { 4582 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4583 4584 // FIXME: This implementation is an ugly hack! 4585 if (PrevDecl) { 4586 PrevDecl->addAttr(::new (Context) WeakAttr()); 4587 return; 4588 } 4589 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4590 return; 4591} 4592 4593void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 4594 IdentifierInfo* AliasName, 4595 SourceLocation PragmaLoc, 4596 SourceLocation NameLoc, 4597 SourceLocation AliasNameLoc) { 4598 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4599 4600 // FIXME: This implementation is an ugly hack! 4601 if (PrevDecl) { 4602 PrevDecl->addAttr(::new (Context) AliasAttr(AliasName->getName())); 4603 PrevDecl->addAttr(::new (Context) WeakAttr()); 4604 return; 4605 } 4606 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4607 return; 4608} 4609