SemaDecl.cpp revision 0130f3cc4ccd5f46361c48d5fe94133d74619424
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 "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/BitVector.h" 34#include "llvm/ADT/STLExtras.h" 35#include <algorithm> 36#include <cstring> 37#include <functional> 38#include <queue> 39using namespace clang; 40 41/// getDeclName - Return a pretty name for the specified decl if possible, or 42/// an empty string if not. This is used for pretty crash reporting. 43std::string Sema::getDeclName(DeclPtrTy d) { 44 Decl *D = d.getAs<Decl>(); 45 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 46 return DN->getQualifiedNameAsString(); 47 return ""; 48} 49 50Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 51 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 52} 53 54/// \brief If the identifier refers to a type name within this scope, 55/// return the declaration of that type. 56/// 57/// This routine performs ordinary name lookup of the identifier II 58/// within the given scope, with optional C++ scope specifier SS, to 59/// determine whether the name refers to a type. If so, returns an 60/// opaque pointer (actually a QualType) corresponding to that 61/// type. Otherwise, returns NULL. 62/// 63/// If name lookup results in an ambiguity, this routine will complain 64/// and then return NULL. 65Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 66 Scope *S, const CXXScopeSpec *SS, 67 bool isClassName) { 68 // C++ [temp.res]p3: 69 // A qualified-id that refers to a type and in which the 70 // nested-name-specifier depends on a template-parameter (14.6.2) 71 // shall be prefixed by the keyword typename to indicate that the 72 // qualified-id denotes a type, forming an 73 // elaborated-type-specifier (7.1.5.3). 74 // 75 // We therefore do not perform any name lookup if the result would 76 // refer to a member of an unknown specialization. 77 if (SS && isUnknownSpecialization(*SS)) { 78 if (!isClassName) 79 return 0; 80 81 // We know from the grammar that this name refers to a type, so build a 82 // TypenameType node to describe the type. 83 // FIXME: Record somewhere that this TypenameType node has no "typename" 84 // keyword associated with it. 85 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 86 II, SS->getRange()).getAsOpaquePtr(); 87 } 88 89 LookupResult Result; 90 LookupParsedName(Result, S, SS, &II, LookupOrdinaryName, false, false); 91 92 NamedDecl *IIDecl = 0; 93 switch (Result.getKind()) { 94 case LookupResult::NotFound: 95 case LookupResult::FoundOverloaded: 96 return 0; 97 98 case LookupResult::Ambiguous: 99 // Recover from type-hiding ambiguities by hiding the type. We'll 100 // do the lookup again when looking for an object, and we can 101 // diagnose the error then. If we don't do this, then the error 102 // about hiding the type will be immediately followed by an error 103 // that only makes sense if the identifier was treated like a type. 104 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) 105 return 0; 106 107 // Look to see if we have a type anywhere in the list of results. 108 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 109 Res != ResEnd; ++Res) { 110 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 111 if (!IIDecl || 112 (*Res)->getLocation().getRawEncoding() < 113 IIDecl->getLocation().getRawEncoding()) 114 IIDecl = *Res; 115 } 116 } 117 118 if (!IIDecl) { 119 // None of the entities we found is a type, so there is no way 120 // to even assume that the result is a type. In this case, don't 121 // complain about the ambiguity. The parser will either try to 122 // perform this lookup again (e.g., as an object name), which 123 // will produce the ambiguity, or will complain that it expected 124 // a type name. 125 return 0; 126 } 127 128 // We found a type within the ambiguous lookup; diagnose the 129 // ambiguity and then return that type. This might be the right 130 // answer, or it might not be, but it suppresses any attempt to 131 // perform the name lookup again. 132 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 133 break; 134 135 case LookupResult::Found: 136 IIDecl = Result.getFoundDecl(); 137 break; 138 } 139 140 assert(IIDecl && "Didn't find decl"); 141 142 QualType T; 143 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 144 // C++ [temp.local]p2: 145 // Within the scope of a class template specialization or 146 // partial specialization, when the injected-class-name is 147 // not followed by a <, it is equivalent to the 148 // injected-class-name followed by the template-argument s 149 // of the class template specialization or partial 150 // specialization enclosed in <>. 151 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 152 if (RD->isInjectedClassName()) 153 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 154 T = Template->getInjectedClassNameType(Context); 155 156 if (T.isNull()) 157 T = Context.getTypeDeclType(TD); 158 159 if (SS) 160 T = getQualifiedNameType(*SS, T); 161 162 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 163 T = Context.getObjCInterfaceType(IDecl); 164 } else 165 return 0; 166 167 return T.getAsOpaquePtr(); 168} 169 170/// isTagName() - This method is called *for error recovery purposes only* 171/// to determine if the specified name is a valid tag name ("struct foo"). If 172/// so, this returns the TST for the tag corresponding to it (TST_enum, 173/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 174/// where the user forgot to specify the tag. 175DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 176 // Do a tag name lookup in this scope. 177 LookupResult R; 178 LookupName(R, S, &II, LookupTagName, false, false); 179 if (R.getKind() == LookupResult::Found) 180 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 181 switch (TD->getTagKind()) { 182 case TagDecl::TK_struct: return DeclSpec::TST_struct; 183 case TagDecl::TK_union: return DeclSpec::TST_union; 184 case TagDecl::TK_class: return DeclSpec::TST_class; 185 case TagDecl::TK_enum: return DeclSpec::TST_enum; 186 } 187 } 188 189 return DeclSpec::TST_unspecified; 190} 191 192bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 193 SourceLocation IILoc, 194 Scope *S, 195 const CXXScopeSpec *SS, 196 TypeTy *&SuggestedType) { 197 // We don't have anything to suggest (yet). 198 SuggestedType = 0; 199 200 // FIXME: Should we move the logic that tries to recover from a missing tag 201 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 202 203 if (!SS) 204 Diag(IILoc, diag::err_unknown_typename) << &II; 205 else if (DeclContext *DC = computeDeclContext(*SS, false)) 206 Diag(IILoc, diag::err_typename_nested_not_found) 207 << &II << DC << SS->getRange(); 208 else if (isDependentScopeSpecifier(*SS)) { 209 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 210 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 211 << SourceRange(SS->getRange().getBegin(), IILoc) 212 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 213 "typename "); 214 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 215 } else { 216 assert(SS && SS->isInvalid() && 217 "Invalid scope specifier has already been diagnosed"); 218 } 219 220 return true; 221} 222 223// Determines the context to return to after temporarily entering a 224// context. This depends in an unnecessarily complicated way on the 225// exact ordering of callbacks from the parser. 226DeclContext *Sema::getContainingDC(DeclContext *DC) { 227 228 // Functions defined inline within classes aren't parsed until we've 229 // finished parsing the top-level class, so the top-level class is 230 // the context we'll need to return to. 231 if (isa<FunctionDecl>(DC)) { 232 DC = DC->getLexicalParent(); 233 234 // A function not defined within a class will always return to its 235 // lexical context. 236 if (!isa<CXXRecordDecl>(DC)) 237 return DC; 238 239 // A C++ inline method/friend is parsed *after* the topmost class 240 // it was declared in is fully parsed ("complete"); the topmost 241 // class is the context we need to return to. 242 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 243 DC = RD; 244 245 // Return the declaration context of the topmost class the inline method is 246 // declared in. 247 return DC; 248 } 249 250 if (isa<ObjCMethodDecl>(DC)) 251 return Context.getTranslationUnitDecl(); 252 253 return DC->getLexicalParent(); 254} 255 256void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 257 assert(getContainingDC(DC) == CurContext && 258 "The next DeclContext should be lexically contained in the current one."); 259 CurContext = DC; 260 S->setEntity(DC); 261} 262 263void Sema::PopDeclContext() { 264 assert(CurContext && "DeclContext imbalance!"); 265 266 CurContext = getContainingDC(CurContext); 267} 268 269/// EnterDeclaratorContext - Used when we must lookup names in the context 270/// of a declarator's nested name specifier. 271void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 272 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 273 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 274 CurContext = DC; 275 assert(CurContext && "No context?"); 276 S->setEntity(CurContext); 277} 278 279void Sema::ExitDeclaratorContext(Scope *S) { 280 S->setEntity(PreDeclaratorDC); 281 PreDeclaratorDC = 0; 282 283 // Reset CurContext to the nearest enclosing context. 284 while (!S->getEntity() && S->getParent()) 285 S = S->getParent(); 286 CurContext = static_cast<DeclContext*>(S->getEntity()); 287 assert(CurContext && "No context?"); 288} 289 290/// \brief Determine whether we allow overloading of the function 291/// PrevDecl with another declaration. 292/// 293/// This routine determines whether overloading is possible, not 294/// whether some new function is actually an overload. It will return 295/// true in C++ (where we can always provide overloads) or, as an 296/// extension, in C when the previous function is already an 297/// overloaded function declaration or has the "overloadable" 298/// attribute. 299static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 300 if (Context.getLangOptions().CPlusPlus) 301 return true; 302 303 if (isa<OverloadedFunctionDecl>(PrevDecl)) 304 return true; 305 306 return PrevDecl->getAttr<OverloadableAttr>() != 0; 307} 308 309/// Add this decl to the scope shadowed decl chains. 310void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 311 // Move up the scope chain until we find the nearest enclosing 312 // non-transparent context. The declaration will be introduced into this 313 // scope. 314 while (S->getEntity() && 315 ((DeclContext *)S->getEntity())->isTransparentContext()) 316 S = S->getParent(); 317 318 // Add scoped declarations into their context, so that they can be 319 // found later. Declarations without a context won't be inserted 320 // into any context. 321 if (AddToContext) 322 CurContext->addDecl(D); 323 324 // Out-of-line function and variable definitions should not be pushed into 325 // scope. 326 if ((isa<FunctionTemplateDecl>(D) && 327 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 328 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 329 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 330 return; 331 332 // If this replaces anything in the current scope, 333 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 334 IEnd = IdResolver.end(); 335 for (; I != IEnd; ++I) { 336 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 337 S->RemoveDecl(DeclPtrTy::make(*I)); 338 IdResolver.RemoveDecl(*I); 339 340 // Should only need to replace one decl. 341 break; 342 } 343 } 344 345 S->AddDecl(DeclPtrTy::make(D)); 346 IdResolver.AddDecl(D); 347} 348 349bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 350 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 351 // Look inside the overload set to determine if any of the declarations 352 // are in scope. (Possibly) build a new overload set containing only 353 // those declarations that are in scope. 354 OverloadedFunctionDecl *NewOvl = 0; 355 bool FoundInScope = false; 356 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 357 FEnd = Ovl->function_end(); 358 F != FEnd; ++F) { 359 NamedDecl *FD = F->get(); 360 if (!isDeclInScope(FD, Ctx, S)) { 361 if (!NewOvl && F != Ovl->function_begin()) { 362 NewOvl = OverloadedFunctionDecl::Create(Context, 363 F->get()->getDeclContext(), 364 F->get()->getDeclName()); 365 D = NewOvl; 366 for (OverloadedFunctionDecl::function_iterator 367 First = Ovl->function_begin(); 368 First != F; ++First) 369 NewOvl->addOverload(*First); 370 } 371 } else { 372 FoundInScope = true; 373 if (NewOvl) 374 NewOvl->addOverload(*F); 375 } 376 } 377 378 return FoundInScope; 379 } 380 381 return IdResolver.isDeclInScope(D, Ctx, Context, S); 382} 383 384void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 385 if (S->decl_empty()) return; 386 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 387 "Scope shouldn't contain decls!"); 388 389 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 390 I != E; ++I) { 391 Decl *TmpD = (*I).getAs<Decl>(); 392 assert(TmpD && "This decl didn't get pushed??"); 393 394 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 395 NamedDecl *D = cast<NamedDecl>(TmpD); 396 397 if (!D->getDeclName()) continue; 398 399 // Diagnose unused variables in this scope. 400 if (!D->isUsed() && !D->hasAttr<UnusedAttr>() && isa<VarDecl>(D) && 401 !isa<ParmVarDecl>(D) && !isa<ImplicitParamDecl>(D) && 402 D->getDeclContext()->isFunctionOrMethod()) 403 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 404 405 // Remove this name from our lexical scope. 406 IdResolver.RemoveDecl(D); 407 } 408} 409 410/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 411/// return 0 if one not found. 412ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 413 // The third "scope" argument is 0 since we aren't enabling lazy built-in 414 // creation from this context. 415 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 416 417 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 418} 419 420/// getNonFieldDeclScope - Retrieves the innermost scope, starting 421/// from S, where a non-field would be declared. This routine copes 422/// with the difference between C and C++ scoping rules in structs and 423/// unions. For example, the following code is well-formed in C but 424/// ill-formed in C++: 425/// @code 426/// struct S6 { 427/// enum { BAR } e; 428/// }; 429/// 430/// void test_S6() { 431/// struct S6 a; 432/// a.e = BAR; 433/// } 434/// @endcode 435/// For the declaration of BAR, this routine will return a different 436/// scope. The scope S will be the scope of the unnamed enumeration 437/// within S6. In C++, this routine will return the scope associated 438/// with S6, because the enumeration's scope is a transparent 439/// context but structures can contain non-field names. In C, this 440/// routine will return the translation unit scope, since the 441/// enumeration's scope is a transparent context and structures cannot 442/// contain non-field names. 443Scope *Sema::getNonFieldDeclScope(Scope *S) { 444 while (((S->getFlags() & Scope::DeclScope) == 0) || 445 (S->getEntity() && 446 ((DeclContext *)S->getEntity())->isTransparentContext()) || 447 (S->isClassScope() && !getLangOptions().CPlusPlus)) 448 S = S->getParent(); 449 return S; 450} 451 452void Sema::InitBuiltinVaListType() { 453 if (!Context.getBuiltinVaListType().isNull()) 454 return; 455 456 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 457 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 458 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 459 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 460} 461 462/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 463/// file scope. lazily create a decl for it. ForRedeclaration is true 464/// if we're creating this built-in in anticipation of redeclaring the 465/// built-in. 466NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 467 Scope *S, bool ForRedeclaration, 468 SourceLocation Loc) { 469 Builtin::ID BID = (Builtin::ID)bid; 470 471 if (Context.BuiltinInfo.hasVAListUse(BID)) 472 InitBuiltinVaListType(); 473 474 ASTContext::GetBuiltinTypeError Error; 475 QualType R = Context.GetBuiltinType(BID, Error); 476 switch (Error) { 477 case ASTContext::GE_None: 478 // Okay 479 break; 480 481 case ASTContext::GE_Missing_stdio: 482 if (ForRedeclaration) 483 Diag(Loc, diag::err_implicit_decl_requires_stdio) 484 << Context.BuiltinInfo.GetName(BID); 485 return 0; 486 487 case ASTContext::GE_Missing_setjmp: 488 if (ForRedeclaration) 489 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 490 << Context.BuiltinInfo.GetName(BID); 491 return 0; 492 } 493 494 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 495 Diag(Loc, diag::ext_implicit_lib_function_decl) 496 << Context.BuiltinInfo.GetName(BID) 497 << R; 498 if (Context.BuiltinInfo.getHeaderName(BID) && 499 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 500 != Diagnostic::Ignored) 501 Diag(Loc, diag::note_please_include_header) 502 << Context.BuiltinInfo.getHeaderName(BID) 503 << Context.BuiltinInfo.GetName(BID); 504 } 505 506 FunctionDecl *New = FunctionDecl::Create(Context, 507 Context.getTranslationUnitDecl(), 508 Loc, II, R, /*DInfo=*/0, 509 FunctionDecl::Extern, false, 510 /*hasPrototype=*/true); 511 New->setImplicit(); 512 513 // Create Decl objects for each parameter, adding them to the 514 // FunctionDecl. 515 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 516 llvm::SmallVector<ParmVarDecl*, 16> Params; 517 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 518 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 519 FT->getArgType(i), /*DInfo=*/0, 520 VarDecl::None, 0)); 521 New->setParams(Context, Params.data(), Params.size()); 522 } 523 524 AddKnownFunctionAttributes(New); 525 526 // TUScope is the translation-unit scope to insert this function into. 527 // FIXME: This is hideous. We need to teach PushOnScopeChains to 528 // relate Scopes to DeclContexts, and probably eliminate CurContext 529 // entirely, but we're not there yet. 530 DeclContext *SavedContext = CurContext; 531 CurContext = Context.getTranslationUnitDecl(); 532 PushOnScopeChains(New, TUScope); 533 CurContext = SavedContext; 534 return New; 535} 536 537/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 538/// same name and scope as a previous declaration 'Old'. Figure out 539/// how to resolve this situation, merging decls or emitting 540/// diagnostics as appropriate. If there was an error, set New to be invalid. 541/// 542void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 543 // If either decl is known invalid already, set the new one to be invalid and 544 // don't bother doing any merging checks. 545 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 546 return New->setInvalidDecl(); 547 548 // Allow multiple definitions for ObjC built-in typedefs. 549 // FIXME: Verify the underlying types are equivalent! 550 if (getLangOptions().ObjC1) { 551 const IdentifierInfo *TypeID = New->getIdentifier(); 552 switch (TypeID->getLength()) { 553 default: break; 554 case 2: 555 if (!TypeID->isStr("id")) 556 break; 557 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 558 // Install the built-in type for 'id', ignoring the current definition. 559 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 560 return; 561 case 5: 562 if (!TypeID->isStr("Class")) 563 break; 564 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 565 // Install the built-in type for 'Class', ignoring the current definition. 566 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 567 return; 568 case 3: 569 if (!TypeID->isStr("SEL")) 570 break; 571 Context.setObjCSelType(Context.getTypeDeclType(New)); 572 return; 573 case 8: 574 if (!TypeID->isStr("Protocol")) 575 break; 576 Context.setObjCProtoType(New->getUnderlyingType()); 577 return; 578 } 579 // Fall through - the typedef name was not a builtin type. 580 } 581 // Verify the old decl was also a type. 582 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 583 if (!Old) { 584 Diag(New->getLocation(), diag::err_redefinition_different_kind) 585 << New->getDeclName(); 586 if (OldD->getLocation().isValid()) 587 Diag(OldD->getLocation(), diag::note_previous_definition); 588 return New->setInvalidDecl(); 589 } 590 591 // Determine the "old" type we'll use for checking and diagnostics. 592 QualType OldType; 593 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 594 OldType = OldTypedef->getUnderlyingType(); 595 else 596 OldType = Context.getTypeDeclType(Old); 597 598 // If the typedef types are not identical, reject them in all languages and 599 // with any extensions enabled. 600 601 if (OldType != New->getUnderlyingType() && 602 Context.getCanonicalType(OldType) != 603 Context.getCanonicalType(New->getUnderlyingType())) { 604 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 605 << New->getUnderlyingType() << OldType; 606 if (Old->getLocation().isValid()) 607 Diag(Old->getLocation(), diag::note_previous_definition); 608 return New->setInvalidDecl(); 609 } 610 611 if (getLangOptions().Microsoft) 612 return; 613 614 // C++ [dcl.typedef]p2: 615 // In a given non-class scope, a typedef specifier can be used to 616 // redefine the name of any type declared in that scope to refer 617 // to the type to which it already refers. 618 if (getLangOptions().CPlusPlus) { 619 if (!isa<CXXRecordDecl>(CurContext)) 620 return; 621 Diag(New->getLocation(), diag::err_redefinition) 622 << New->getDeclName(); 623 Diag(Old->getLocation(), diag::note_previous_definition); 624 return New->setInvalidDecl(); 625 } 626 627 // If we have a redefinition of a typedef in C, emit a warning. This warning 628 // is normally mapped to an error, but can be controlled with 629 // -Wtypedef-redefinition. If either the original or the redefinition is 630 // in a system header, don't emit this for compatibility with GCC. 631 if (PP.getDiagnostics().getSuppressSystemWarnings() && 632 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 633 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 634 return; 635 636 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 637 << New->getDeclName(); 638 Diag(Old->getLocation(), diag::note_previous_definition); 639 return; 640} 641 642/// DeclhasAttr - returns true if decl Declaration already has the target 643/// attribute. 644static bool 645DeclHasAttr(const Decl *decl, const Attr *target) { 646 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 647 if (attr->getKind() == target->getKind()) 648 return true; 649 650 return false; 651} 652 653/// MergeAttributes - append attributes from the Old decl to the New one. 654static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 655 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 656 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 657 Attr *NewAttr = attr->clone(C); 658 NewAttr->setInherited(true); 659 New->addAttr(NewAttr); 660 } 661 } 662} 663 664/// Used in MergeFunctionDecl to keep track of function parameters in 665/// C. 666struct GNUCompatibleParamWarning { 667 ParmVarDecl *OldParm; 668 ParmVarDecl *NewParm; 669 QualType PromotedType; 670}; 671 672/// MergeFunctionDecl - We just parsed a function 'New' from 673/// declarator D which has the same name and scope as a previous 674/// declaration 'Old'. Figure out how to resolve this situation, 675/// merging decls or emitting diagnostics as appropriate. 676/// 677/// In C++, New and Old must be declarations that are not 678/// overloaded. Use IsOverload to determine whether New and Old are 679/// overloaded, and to select the Old declaration that New should be 680/// merged with. 681/// 682/// Returns true if there was an error, false otherwise. 683bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 684 assert(!isa<OverloadedFunctionDecl>(OldD) && 685 "Cannot merge with an overloaded function declaration"); 686 687 // Verify the old decl was also a function. 688 FunctionDecl *Old = 0; 689 if (FunctionTemplateDecl *OldFunctionTemplate 690 = dyn_cast<FunctionTemplateDecl>(OldD)) 691 Old = OldFunctionTemplate->getTemplatedDecl(); 692 else 693 Old = dyn_cast<FunctionDecl>(OldD); 694 if (!Old) { 695 Diag(New->getLocation(), diag::err_redefinition_different_kind) 696 << New->getDeclName(); 697 Diag(OldD->getLocation(), diag::note_previous_definition); 698 return true; 699 } 700 701 // Determine whether the previous declaration was a definition, 702 // implicit declaration, or a declaration. 703 diag::kind PrevDiag; 704 if (Old->isThisDeclarationADefinition()) 705 PrevDiag = diag::note_previous_definition; 706 else if (Old->isImplicit()) 707 PrevDiag = diag::note_previous_implicit_declaration; 708 else 709 PrevDiag = diag::note_previous_declaration; 710 711 QualType OldQType = Context.getCanonicalType(Old->getType()); 712 QualType NewQType = Context.getCanonicalType(New->getType()); 713 714 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 715 New->getStorageClass() == FunctionDecl::Static && 716 Old->getStorageClass() != FunctionDecl::Static) { 717 Diag(New->getLocation(), diag::err_static_non_static) 718 << New; 719 Diag(Old->getLocation(), PrevDiag); 720 return true; 721 } 722 723 if (getLangOptions().CPlusPlus) { 724 // (C++98 13.1p2): 725 // Certain function declarations cannot be overloaded: 726 // -- Function declarations that differ only in the return type 727 // cannot be overloaded. 728 QualType OldReturnType 729 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 730 QualType NewReturnType 731 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 732 if (OldReturnType != NewReturnType) { 733 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 734 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 735 return true; 736 } 737 738 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 739 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 740 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 741 NewMethod->getLexicalDeclContext()->isRecord()) { 742 // -- Member function declarations with the same name and the 743 // same parameter types cannot be overloaded if any of them 744 // is a static member function declaration. 745 if (OldMethod->isStatic() || NewMethod->isStatic()) { 746 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 747 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 748 return true; 749 } 750 751 // C++ [class.mem]p1: 752 // [...] A member shall not be declared twice in the 753 // member-specification, except that a nested class or member 754 // class template can be declared and then later defined. 755 unsigned NewDiag; 756 if (isa<CXXConstructorDecl>(OldMethod)) 757 NewDiag = diag::err_constructor_redeclared; 758 else if (isa<CXXDestructorDecl>(NewMethod)) 759 NewDiag = diag::err_destructor_redeclared; 760 else if (isa<CXXConversionDecl>(NewMethod)) 761 NewDiag = diag::err_conv_function_redeclared; 762 else 763 NewDiag = diag::err_member_redeclared; 764 765 Diag(New->getLocation(), NewDiag); 766 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 767 } 768 769 // (C++98 8.3.5p3): 770 // All declarations for a function shall agree exactly in both the 771 // return type and the parameter-type-list. 772 if (OldQType == NewQType) 773 return MergeCompatibleFunctionDecls(New, Old); 774 775 // Fall through for conflicting redeclarations and redefinitions. 776 } 777 778 // C: Function types need to be compatible, not identical. This handles 779 // duplicate function decls like "void f(int); void f(enum X);" properly. 780 if (!getLangOptions().CPlusPlus && 781 Context.typesAreCompatible(OldQType, NewQType)) { 782 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 783 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 784 const FunctionProtoType *OldProto = 0; 785 if (isa<FunctionNoProtoType>(NewFuncType) && 786 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 787 // The old declaration provided a function prototype, but the 788 // new declaration does not. Merge in the prototype. 789 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 790 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 791 OldProto->arg_type_end()); 792 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 793 ParamTypes.data(), ParamTypes.size(), 794 OldProto->isVariadic(), 795 OldProto->getTypeQuals()); 796 New->setType(NewQType); 797 New->setHasInheritedPrototype(); 798 799 // Synthesize a parameter for each argument type. 800 llvm::SmallVector<ParmVarDecl*, 16> Params; 801 for (FunctionProtoType::arg_type_iterator 802 ParamType = OldProto->arg_type_begin(), 803 ParamEnd = OldProto->arg_type_end(); 804 ParamType != ParamEnd; ++ParamType) { 805 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 806 SourceLocation(), 0, 807 *ParamType, /*DInfo=*/0, 808 VarDecl::None, 0); 809 Param->setImplicit(); 810 Params.push_back(Param); 811 } 812 813 New->setParams(Context, Params.data(), Params.size()); 814 } 815 816 return MergeCompatibleFunctionDecls(New, Old); 817 } 818 819 // GNU C permits a K&R definition to follow a prototype declaration 820 // if the declared types of the parameters in the K&R definition 821 // match the types in the prototype declaration, even when the 822 // promoted types of the parameters from the K&R definition differ 823 // from the types in the prototype. GCC then keeps the types from 824 // the prototype. 825 // 826 // If a variadic prototype is followed by a non-variadic K&R definition, 827 // the K&R definition becomes variadic. This is sort of an edge case, but 828 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 829 // C99 6.9.1p8. 830 if (!getLangOptions().CPlusPlus && 831 Old->hasPrototype() && !New->hasPrototype() && 832 New->getType()->getAs<FunctionProtoType>() && 833 Old->getNumParams() == New->getNumParams()) { 834 llvm::SmallVector<QualType, 16> ArgTypes; 835 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 836 const FunctionProtoType *OldProto 837 = Old->getType()->getAs<FunctionProtoType>(); 838 const FunctionProtoType *NewProto 839 = New->getType()->getAs<FunctionProtoType>(); 840 841 // Determine whether this is the GNU C extension. 842 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 843 NewProto->getResultType()); 844 bool LooseCompatible = !MergedReturn.isNull(); 845 for (unsigned Idx = 0, End = Old->getNumParams(); 846 LooseCompatible && Idx != End; ++Idx) { 847 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 848 ParmVarDecl *NewParm = New->getParamDecl(Idx); 849 if (Context.typesAreCompatible(OldParm->getType(), 850 NewProto->getArgType(Idx))) { 851 ArgTypes.push_back(NewParm->getType()); 852 } else if (Context.typesAreCompatible(OldParm->getType(), 853 NewParm->getType())) { 854 GNUCompatibleParamWarning Warn 855 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 856 Warnings.push_back(Warn); 857 ArgTypes.push_back(NewParm->getType()); 858 } else 859 LooseCompatible = false; 860 } 861 862 if (LooseCompatible) { 863 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 864 Diag(Warnings[Warn].NewParm->getLocation(), 865 diag::ext_param_promoted_not_compatible_with_prototype) 866 << Warnings[Warn].PromotedType 867 << Warnings[Warn].OldParm->getType(); 868 Diag(Warnings[Warn].OldParm->getLocation(), 869 diag::note_previous_declaration); 870 } 871 872 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 873 ArgTypes.size(), 874 OldProto->isVariadic(), 0)); 875 return MergeCompatibleFunctionDecls(New, Old); 876 } 877 878 // Fall through to diagnose conflicting types. 879 } 880 881 // A function that has already been declared has been redeclared or defined 882 // with a different type- show appropriate diagnostic 883 if (unsigned BuiltinID = Old->getBuiltinID()) { 884 // The user has declared a builtin function with an incompatible 885 // signature. 886 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 887 // The function the user is redeclaring is a library-defined 888 // function like 'malloc' or 'printf'. Warn about the 889 // redeclaration, then pretend that we don't know about this 890 // library built-in. 891 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 892 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 893 << Old << Old->getType(); 894 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 895 Old->setInvalidDecl(); 896 return false; 897 } 898 899 PrevDiag = diag::note_previous_builtin_declaration; 900 } 901 902 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 903 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 904 return true; 905} 906 907/// \brief Completes the merge of two function declarations that are 908/// known to be compatible. 909/// 910/// This routine handles the merging of attributes and other 911/// properties of function declarations form the old declaration to 912/// the new declaration, once we know that New is in fact a 913/// redeclaration of Old. 914/// 915/// \returns false 916bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 917 // Merge the attributes 918 MergeAttributes(New, Old, Context); 919 920 // Merge the storage class. 921 if (Old->getStorageClass() != FunctionDecl::Extern && 922 Old->getStorageClass() != FunctionDecl::None) 923 New->setStorageClass(Old->getStorageClass()); 924 925 // Merge "pure" flag. 926 if (Old->isPure()) 927 New->setPure(); 928 929 // Merge the "deleted" flag. 930 if (Old->isDeleted()) 931 New->setDeleted(); 932 933 if (getLangOptions().CPlusPlus) 934 return MergeCXXFunctionDecl(New, Old); 935 936 return false; 937} 938 939/// MergeVarDecl - We just parsed a variable 'New' which has the same name 940/// and scope as a previous declaration 'Old'. Figure out how to resolve this 941/// situation, merging decls or emitting diagnostics as appropriate. 942/// 943/// Tentative definition rules (C99 6.9.2p2) are checked by 944/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 945/// definitions here, since the initializer hasn't been attached. 946/// 947void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 948 // If either decl is invalid, make sure the new one is marked invalid and 949 // don't do any other checking. 950 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 951 return New->setInvalidDecl(); 952 953 // Verify the old decl was also a variable. 954 VarDecl *Old = dyn_cast<VarDecl>(OldD); 955 if (!Old) { 956 Diag(New->getLocation(), diag::err_redefinition_different_kind) 957 << New->getDeclName(); 958 Diag(OldD->getLocation(), diag::note_previous_definition); 959 return New->setInvalidDecl(); 960 } 961 962 MergeAttributes(New, Old, Context); 963 964 // Merge the types 965 QualType MergedT; 966 if (getLangOptions().CPlusPlus) { 967 if (Context.hasSameType(New->getType(), Old->getType())) 968 MergedT = New->getType(); 969 // C++ [basic.types]p7: 970 // [...] The declared type of an array object might be an array of 971 // unknown size and therefore be incomplete at one point in a 972 // translation unit and complete later on; [...] 973 else if (Old->getType()->isIncompleteArrayType() && 974 New->getType()->isArrayType()) { 975 CanQual<ArrayType> OldArray 976 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 977 CanQual<ArrayType> NewArray 978 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 979 if (OldArray->getElementType() == NewArray->getElementType()) 980 MergedT = New->getType(); 981 } 982 } else { 983 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 984 } 985 if (MergedT.isNull()) { 986 Diag(New->getLocation(), diag::err_redefinition_different_type) 987 << New->getDeclName(); 988 Diag(Old->getLocation(), diag::note_previous_definition); 989 return New->setInvalidDecl(); 990 } 991 New->setType(MergedT); 992 993 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 994 if (New->getStorageClass() == VarDecl::Static && 995 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 996 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 997 Diag(Old->getLocation(), diag::note_previous_definition); 998 return New->setInvalidDecl(); 999 } 1000 // C99 6.2.2p4: 1001 // For an identifier declared with the storage-class specifier 1002 // extern in a scope in which a prior declaration of that 1003 // identifier is visible,23) if the prior declaration specifies 1004 // internal or external linkage, the linkage of the identifier at 1005 // the later declaration is the same as the linkage specified at 1006 // the prior declaration. If no prior declaration is visible, or 1007 // if the prior declaration specifies no linkage, then the 1008 // identifier has external linkage. 1009 if (New->hasExternalStorage() && Old->hasLinkage()) 1010 /* Okay */; 1011 else if (New->getStorageClass() != VarDecl::Static && 1012 Old->getStorageClass() == VarDecl::Static) { 1013 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1014 Diag(Old->getLocation(), diag::note_previous_definition); 1015 return New->setInvalidDecl(); 1016 } 1017 1018 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1019 1020 // FIXME: The test for external storage here seems wrong? We still 1021 // need to check for mismatches. 1022 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1023 // Don't complain about out-of-line definitions of static members. 1024 !(Old->getLexicalDeclContext()->isRecord() && 1025 !New->getLexicalDeclContext()->isRecord())) { 1026 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1027 Diag(Old->getLocation(), diag::note_previous_definition); 1028 return New->setInvalidDecl(); 1029 } 1030 1031 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1032 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1033 Diag(Old->getLocation(), diag::note_previous_definition); 1034 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1035 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1036 Diag(Old->getLocation(), diag::note_previous_definition); 1037 } 1038 1039 // Keep a chain of previous declarations. 1040 New->setPreviousDeclaration(Old); 1041} 1042 1043/// CheckFallThrough - Check that we don't fall off the end of a 1044/// Statement that should return a value. 1045/// 1046/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1047/// MaybeFallThrough iff we might or might not fall off the end, 1048/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1049/// return. We assume NeverFallThrough iff we never fall off the end of the 1050/// statement but we may return. We assume that functions not marked noreturn 1051/// will return. 1052Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1053 // FIXME: Eventually share this CFG object when we have other warnings based 1054 // of the CFG. This can be done using AnalysisContext. 1055 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1056 1057 // FIXME: They should never return 0, fix that, delete this code. 1058 if (cfg == 0) 1059 // FIXME: This should be NeverFallThrough 1060 return NeverFallThroughOrReturn; 1061 // The CFG leaves in dead things, and we don't want to dead code paths to 1062 // confuse us, so we mark all live things first. 1063 std::queue<CFGBlock*> workq; 1064 llvm::BitVector live(cfg->getNumBlockIDs()); 1065 // Prep work queue 1066 workq.push(&cfg->getEntry()); 1067 // Solve 1068 while (!workq.empty()) { 1069 CFGBlock *item = workq.front(); 1070 workq.pop(); 1071 live.set(item->getBlockID()); 1072 for (CFGBlock::succ_iterator I=item->succ_begin(), 1073 E=item->succ_end(); 1074 I != E; 1075 ++I) { 1076 if ((*I) && !live[(*I)->getBlockID()]) { 1077 live.set((*I)->getBlockID()); 1078 workq.push(*I); 1079 } 1080 } 1081 } 1082 1083 // Now we know what is live, we check the live precessors of the exit block 1084 // and look for fall through paths, being careful to ignore normal returns, 1085 // and exceptional paths. 1086 bool HasLiveReturn = false; 1087 bool HasFakeEdge = false; 1088 bool HasPlainEdge = false; 1089 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1090 E = cfg->getExit().pred_end(); 1091 I != E; 1092 ++I) { 1093 CFGBlock& B = **I; 1094 if (!live[B.getBlockID()]) 1095 continue; 1096 if (B.size() == 0) { 1097 // A labeled empty statement, or the entry block... 1098 HasPlainEdge = true; 1099 continue; 1100 } 1101 Stmt *S = B[B.size()-1]; 1102 if (isa<ReturnStmt>(S)) { 1103 HasLiveReturn = true; 1104 continue; 1105 } 1106 if (isa<ObjCAtThrowStmt>(S)) { 1107 HasFakeEdge = true; 1108 continue; 1109 } 1110 if (isa<CXXThrowExpr>(S)) { 1111 HasFakeEdge = true; 1112 continue; 1113 } 1114 bool NoReturnEdge = false; 1115 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1116 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1117 if (CEE->getType().getNoReturnAttr()) { 1118 NoReturnEdge = true; 1119 HasFakeEdge = true; 1120 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1121 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1122 if (FD->hasAttr<NoReturnAttr>()) { 1123 NoReturnEdge = true; 1124 HasFakeEdge = true; 1125 } 1126 } 1127 } 1128 } 1129 // FIXME: Add noreturn message sends. 1130 if (NoReturnEdge == false) 1131 HasPlainEdge = true; 1132 } 1133 if (!HasPlainEdge) { 1134 if (HasLiveReturn) 1135 return NeverFallThrough; 1136 return NeverFallThroughOrReturn; 1137 } 1138 if (HasFakeEdge || HasLiveReturn) 1139 return MaybeFallThrough; 1140 // This says AlwaysFallThrough for calls to functions that are not marked 1141 // noreturn, that don't return. If people would like this warning to be more 1142 // accurate, such functions should be marked as noreturn. 1143 return AlwaysFallThrough; 1144} 1145 1146/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1147/// function that should return a value. Check that we don't fall off the end 1148/// of a noreturn function. We assume that functions and blocks not marked 1149/// noreturn will return. 1150void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1151 // FIXME: Would be nice if we had a better way to control cascading errors, 1152 // but for now, avoid them. The problem is that when Parse sees: 1153 // int foo() { return a; } 1154 // The return is eaten and the Sema code sees just: 1155 // int foo() { } 1156 // which this code would then warn about. 1157 if (getDiagnostics().hasErrorOccurred()) 1158 return; 1159 1160 bool ReturnsVoid = false; 1161 bool HasNoReturn = false; 1162 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1163 // If the result type of the function is a dependent type, we don't know 1164 // whether it will be void or not, so don't 1165 if (FD->getResultType()->isDependentType()) 1166 return; 1167 if (FD->getResultType()->isVoidType()) 1168 ReturnsVoid = true; 1169 if (FD->hasAttr<NoReturnAttr>()) 1170 HasNoReturn = true; 1171 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1172 if (MD->getResultType()->isVoidType()) 1173 ReturnsVoid = true; 1174 if (MD->hasAttr<NoReturnAttr>()) 1175 HasNoReturn = true; 1176 } 1177 1178 // Short circuit for compilation speed. 1179 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1180 == Diagnostic::Ignored || ReturnsVoid) 1181 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1182 == Diagnostic::Ignored || !HasNoReturn) 1183 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1184 == Diagnostic::Ignored || !ReturnsVoid)) 1185 return; 1186 // FIXME: Function try block 1187 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1188 switch (CheckFallThrough(Body)) { 1189 case MaybeFallThrough: 1190 if (HasNoReturn) 1191 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1192 else if (!ReturnsVoid) 1193 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1194 break; 1195 case AlwaysFallThrough: 1196 if (HasNoReturn) 1197 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1198 else if (!ReturnsVoid) 1199 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1200 break; 1201 case NeverFallThroughOrReturn: 1202 if (ReturnsVoid && !HasNoReturn) 1203 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1204 break; 1205 case NeverFallThrough: 1206 break; 1207 } 1208 } 1209} 1210 1211/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1212/// that should return a value. Check that we don't fall off the end of a 1213/// noreturn block. We assume that functions and blocks not marked noreturn 1214/// will return. 1215void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1216 // FIXME: Would be nice if we had a better way to control cascading errors, 1217 // but for now, avoid them. The problem is that when Parse sees: 1218 // int foo() { return a; } 1219 // The return is eaten and the Sema code sees just: 1220 // int foo() { } 1221 // which this code would then warn about. 1222 if (getDiagnostics().hasErrorOccurred()) 1223 return; 1224 bool ReturnsVoid = false; 1225 bool HasNoReturn = false; 1226 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1227 if (FT->getResultType()->isVoidType()) 1228 ReturnsVoid = true; 1229 if (FT->getNoReturnAttr()) 1230 HasNoReturn = true; 1231 } 1232 1233 // Short circuit for compilation speed. 1234 if (ReturnsVoid 1235 && !HasNoReturn 1236 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1237 == Diagnostic::Ignored || !ReturnsVoid)) 1238 return; 1239 // FIXME: Funtion try block 1240 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1241 switch (CheckFallThrough(Body)) { 1242 case MaybeFallThrough: 1243 if (HasNoReturn) 1244 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1245 else if (!ReturnsVoid) 1246 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1247 break; 1248 case AlwaysFallThrough: 1249 if (HasNoReturn) 1250 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1251 else if (!ReturnsVoid) 1252 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1253 break; 1254 case NeverFallThroughOrReturn: 1255 if (ReturnsVoid) 1256 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1257 break; 1258 case NeverFallThrough: 1259 break; 1260 } 1261 } 1262} 1263 1264/// CheckParmsForFunctionDef - Check that the parameters of the given 1265/// function are appropriate for the definition of a function. This 1266/// takes care of any checks that cannot be performed on the 1267/// declaration itself, e.g., that the types of each of the function 1268/// parameters are complete. 1269bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1270 bool HasInvalidParm = false; 1271 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1272 ParmVarDecl *Param = FD->getParamDecl(p); 1273 1274 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1275 // function declarator that is part of a function definition of 1276 // that function shall not have incomplete type. 1277 // 1278 // This is also C++ [dcl.fct]p6. 1279 if (!Param->isInvalidDecl() && 1280 RequireCompleteType(Param->getLocation(), Param->getType(), 1281 diag::err_typecheck_decl_incomplete_type)) { 1282 Param->setInvalidDecl(); 1283 HasInvalidParm = true; 1284 } 1285 1286 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1287 // declaration of each parameter shall include an identifier. 1288 if (Param->getIdentifier() == 0 && 1289 !Param->isImplicit() && 1290 !getLangOptions().CPlusPlus) 1291 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1292 } 1293 1294 return HasInvalidParm; 1295} 1296 1297/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1298/// no declarator (e.g. "struct foo;") is parsed. 1299Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1300 // FIXME: Error on auto/register at file scope 1301 // FIXME: Error on inline/virtual/explicit 1302 // FIXME: Error on invalid restrict 1303 // FIXME: Warn on useless __thread 1304 // FIXME: Warn on useless const/volatile 1305 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1306 // FIXME: Warn on useless attributes 1307 Decl *TagD = 0; 1308 TagDecl *Tag = 0; 1309 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1310 DS.getTypeSpecType() == DeclSpec::TST_struct || 1311 DS.getTypeSpecType() == DeclSpec::TST_union || 1312 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1313 TagD = static_cast<Decl *>(DS.getTypeRep()); 1314 1315 if (!TagD) // We probably had an error 1316 return DeclPtrTy(); 1317 1318 // Note that the above type specs guarantee that the 1319 // type rep is a Decl, whereas in many of the others 1320 // it's a Type. 1321 Tag = dyn_cast<TagDecl>(TagD); 1322 } 1323 1324 if (DS.isFriendSpecified()) { 1325 // If we're dealing with a class template decl, assume that the 1326 // template routines are handling it. 1327 if (TagD && isa<ClassTemplateDecl>(TagD)) 1328 return DeclPtrTy(); 1329 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1330 } 1331 1332 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1333 // If there are attributes in the DeclSpec, apply them to the record. 1334 if (const AttributeList *AL = DS.getAttributes()) 1335 ProcessDeclAttributeList(S, Record, AL); 1336 1337 if (!Record->getDeclName() && Record->isDefinition() && 1338 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1339 if (getLangOptions().CPlusPlus || 1340 Record->getDeclContext()->isRecord()) 1341 return BuildAnonymousStructOrUnion(S, DS, Record); 1342 1343 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1344 << DS.getSourceRange(); 1345 } 1346 1347 // Microsoft allows unnamed struct/union fields. Don't complain 1348 // about them. 1349 // FIXME: Should we support Microsoft's extensions in this area? 1350 if (Record->getDeclName() && getLangOptions().Microsoft) 1351 return DeclPtrTy::make(Tag); 1352 } 1353 1354 if (!DS.isMissingDeclaratorOk() && 1355 DS.getTypeSpecType() != DeclSpec::TST_error) { 1356 // Warn about typedefs of enums without names, since this is an 1357 // extension in both Microsoft an GNU. 1358 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1359 Tag && isa<EnumDecl>(Tag)) { 1360 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1361 << DS.getSourceRange(); 1362 return DeclPtrTy::make(Tag); 1363 } 1364 1365 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1366 << DS.getSourceRange(); 1367 return DeclPtrTy(); 1368 } 1369 1370 return DeclPtrTy::make(Tag); 1371} 1372 1373/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1374/// anonymous struct or union AnonRecord into the owning context Owner 1375/// and scope S. This routine will be invoked just after we realize 1376/// that an unnamed union or struct is actually an anonymous union or 1377/// struct, e.g., 1378/// 1379/// @code 1380/// union { 1381/// int i; 1382/// float f; 1383/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1384/// // f into the surrounding scope.x 1385/// @endcode 1386/// 1387/// This routine is recursive, injecting the names of nested anonymous 1388/// structs/unions into the owning context and scope as well. 1389bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1390 RecordDecl *AnonRecord) { 1391 bool Invalid = false; 1392 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1393 FEnd = AnonRecord->field_end(); 1394 F != FEnd; ++F) { 1395 if ((*F)->getDeclName()) { 1396 LookupResult R; 1397 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1398 LookupOrdinaryName, true); 1399 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1400 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1401 // C++ [class.union]p2: 1402 // The names of the members of an anonymous union shall be 1403 // distinct from the names of any other entity in the 1404 // scope in which the anonymous union is declared. 1405 unsigned diagKind 1406 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1407 : diag::err_anonymous_struct_member_redecl; 1408 Diag((*F)->getLocation(), diagKind) 1409 << (*F)->getDeclName(); 1410 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1411 Invalid = true; 1412 } else { 1413 // C++ [class.union]p2: 1414 // For the purpose of name lookup, after the anonymous union 1415 // definition, the members of the anonymous union are 1416 // considered to have been defined in the scope in which the 1417 // anonymous union is declared. 1418 Owner->makeDeclVisibleInContext(*F); 1419 S->AddDecl(DeclPtrTy::make(*F)); 1420 IdResolver.AddDecl(*F); 1421 } 1422 } else if (const RecordType *InnerRecordType 1423 = (*F)->getType()->getAs<RecordType>()) { 1424 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1425 if (InnerRecord->isAnonymousStructOrUnion()) 1426 Invalid = Invalid || 1427 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1428 } 1429 } 1430 1431 return Invalid; 1432} 1433 1434/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1435/// anonymous structure or union. Anonymous unions are a C++ feature 1436/// (C++ [class.union]) and a GNU C extension; anonymous structures 1437/// are a GNU C and GNU C++ extension. 1438Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1439 RecordDecl *Record) { 1440 DeclContext *Owner = Record->getDeclContext(); 1441 1442 // Diagnose whether this anonymous struct/union is an extension. 1443 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1444 Diag(Record->getLocation(), diag::ext_anonymous_union); 1445 else if (!Record->isUnion()) 1446 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1447 1448 // C and C++ require different kinds of checks for anonymous 1449 // structs/unions. 1450 bool Invalid = false; 1451 if (getLangOptions().CPlusPlus) { 1452 const char* PrevSpec = 0; 1453 unsigned DiagID; 1454 // C++ [class.union]p3: 1455 // Anonymous unions declared in a named namespace or in the 1456 // global namespace shall be declared static. 1457 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1458 (isa<TranslationUnitDecl>(Owner) || 1459 (isa<NamespaceDecl>(Owner) && 1460 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1461 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1462 Invalid = true; 1463 1464 // Recover by adding 'static'. 1465 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1466 PrevSpec, DiagID); 1467 } 1468 // C++ [class.union]p3: 1469 // A storage class is not allowed in a declaration of an 1470 // anonymous union in a class scope. 1471 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1472 isa<RecordDecl>(Owner)) { 1473 Diag(DS.getStorageClassSpecLoc(), 1474 diag::err_anonymous_union_with_storage_spec); 1475 Invalid = true; 1476 1477 // Recover by removing the storage specifier. 1478 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1479 PrevSpec, DiagID); 1480 } 1481 1482 // C++ [class.union]p2: 1483 // The member-specification of an anonymous union shall only 1484 // define non-static data members. [Note: nested types and 1485 // functions cannot be declared within an anonymous union. ] 1486 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1487 MemEnd = Record->decls_end(); 1488 Mem != MemEnd; ++Mem) { 1489 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1490 // C++ [class.union]p3: 1491 // An anonymous union shall not have private or protected 1492 // members (clause 11). 1493 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1494 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1495 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1496 Invalid = true; 1497 } 1498 } else if ((*Mem)->isImplicit()) { 1499 // Any implicit members are fine. 1500 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1501 // This is a type that showed up in an 1502 // elaborated-type-specifier inside the anonymous struct or 1503 // union, but which actually declares a type outside of the 1504 // anonymous struct or union. It's okay. 1505 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1506 if (!MemRecord->isAnonymousStructOrUnion() && 1507 MemRecord->getDeclName()) { 1508 // This is a nested type declaration. 1509 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1510 << (int)Record->isUnion(); 1511 Invalid = true; 1512 } 1513 } else { 1514 // We have something that isn't a non-static data 1515 // member. Complain about it. 1516 unsigned DK = diag::err_anonymous_record_bad_member; 1517 if (isa<TypeDecl>(*Mem)) 1518 DK = diag::err_anonymous_record_with_type; 1519 else if (isa<FunctionDecl>(*Mem)) 1520 DK = diag::err_anonymous_record_with_function; 1521 else if (isa<VarDecl>(*Mem)) 1522 DK = diag::err_anonymous_record_with_static; 1523 Diag((*Mem)->getLocation(), DK) 1524 << (int)Record->isUnion(); 1525 Invalid = true; 1526 } 1527 } 1528 } 1529 1530 if (!Record->isUnion() && !Owner->isRecord()) { 1531 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1532 << (int)getLangOptions().CPlusPlus; 1533 Invalid = true; 1534 } 1535 1536 // Mock up a declarator. 1537 Declarator Dc(DS, Declarator::TypeNameContext); 1538 DeclaratorInfo *DInfo = 0; 1539 GetTypeForDeclarator(Dc, S, &DInfo); 1540 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1541 1542 // Create a declaration for this anonymous struct/union. 1543 NamedDecl *Anon = 0; 1544 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1545 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1546 /*IdentifierInfo=*/0, 1547 Context.getTypeDeclType(Record), 1548 DInfo, 1549 /*BitWidth=*/0, /*Mutable=*/false); 1550 Anon->setAccess(AS_public); 1551 if (getLangOptions().CPlusPlus) 1552 FieldCollector->Add(cast<FieldDecl>(Anon)); 1553 } else { 1554 VarDecl::StorageClass SC; 1555 switch (DS.getStorageClassSpec()) { 1556 default: assert(0 && "Unknown storage class!"); 1557 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1558 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1559 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1560 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1561 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1562 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1563 case DeclSpec::SCS_mutable: 1564 // mutable can only appear on non-static class members, so it's always 1565 // an error here 1566 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1567 Invalid = true; 1568 SC = VarDecl::None; 1569 break; 1570 } 1571 1572 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1573 /*IdentifierInfo=*/0, 1574 Context.getTypeDeclType(Record), 1575 DInfo, 1576 SC); 1577 } 1578 Anon->setImplicit(); 1579 1580 // Add the anonymous struct/union object to the current 1581 // context. We'll be referencing this object when we refer to one of 1582 // its members. 1583 Owner->addDecl(Anon); 1584 1585 // Inject the members of the anonymous struct/union into the owning 1586 // context and into the identifier resolver chain for name lookup 1587 // purposes. 1588 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1589 Invalid = true; 1590 1591 // Mark this as an anonymous struct/union type. Note that we do not 1592 // do this until after we have already checked and injected the 1593 // members of this anonymous struct/union type, because otherwise 1594 // the members could be injected twice: once by DeclContext when it 1595 // builds its lookup table, and once by 1596 // InjectAnonymousStructOrUnionMembers. 1597 Record->setAnonymousStructOrUnion(true); 1598 1599 if (Invalid) 1600 Anon->setInvalidDecl(); 1601 1602 return DeclPtrTy::make(Anon); 1603} 1604 1605 1606/// GetNameForDeclarator - Determine the full declaration name for the 1607/// given Declarator. 1608DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1609 switch (D.getKind()) { 1610 case Declarator::DK_Abstract: 1611 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1612 return DeclarationName(); 1613 1614 case Declarator::DK_Normal: 1615 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1616 return DeclarationName(D.getIdentifier()); 1617 1618 case Declarator::DK_Constructor: { 1619 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1620 return Context.DeclarationNames.getCXXConstructorName( 1621 Context.getCanonicalType(Ty)); 1622 } 1623 1624 case Declarator::DK_Destructor: { 1625 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1626 return Context.DeclarationNames.getCXXDestructorName( 1627 Context.getCanonicalType(Ty)); 1628 } 1629 1630 case Declarator::DK_Conversion: { 1631 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1632 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1633 return Context.DeclarationNames.getCXXConversionFunctionName( 1634 Context.getCanonicalType(Ty)); 1635 } 1636 1637 case Declarator::DK_Operator: 1638 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1639 return Context.DeclarationNames.getCXXOperatorName( 1640 D.getOverloadedOperator()); 1641 1642 case Declarator::DK_TemplateId: { 1643 TemplateName Name 1644 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1645 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1646 return Template->getDeclName(); 1647 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1648 return Ovl->getDeclName(); 1649 1650 return DeclarationName(); 1651 } 1652 } 1653 1654 assert(false && "Unknown name kind"); 1655 return DeclarationName(); 1656} 1657 1658/// isNearlyMatchingFunction - Determine whether the C++ functions 1659/// Declaration and Definition are "nearly" matching. This heuristic 1660/// is used to improve diagnostics in the case where an out-of-line 1661/// function definition doesn't match any declaration within 1662/// the class or namespace. 1663static bool isNearlyMatchingFunction(ASTContext &Context, 1664 FunctionDecl *Declaration, 1665 FunctionDecl *Definition) { 1666 if (Declaration->param_size() != Definition->param_size()) 1667 return false; 1668 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1669 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1670 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1671 1672 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1673 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1674 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1675 return false; 1676 } 1677 1678 return true; 1679} 1680 1681Sema::DeclPtrTy 1682Sema::HandleDeclarator(Scope *S, Declarator &D, 1683 MultiTemplateParamsArg TemplateParamLists, 1684 bool IsFunctionDefinition) { 1685 DeclarationName Name = GetNameForDeclarator(D); 1686 1687 // All of these full declarators require an identifier. If it doesn't have 1688 // one, the ParsedFreeStandingDeclSpec action should be used. 1689 if (!Name) { 1690 if (!D.isInvalidType()) // Reject this if we think it is valid. 1691 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1692 diag::err_declarator_need_ident) 1693 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1694 return DeclPtrTy(); 1695 } 1696 1697 // The scope passed in may not be a decl scope. Zip up the scope tree until 1698 // we find one that is. 1699 while ((S->getFlags() & Scope::DeclScope) == 0 || 1700 (S->getFlags() & Scope::TemplateParamScope) != 0) 1701 S = S->getParent(); 1702 1703 // If this is an out-of-line definition of a member of a class template 1704 // or class template partial specialization, we may need to rebuild the 1705 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1706 // for more information. 1707 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1708 // handle expressions properly. 1709 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1710 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1711 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1712 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1713 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1714 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1715 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1716 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1717 // FIXME: Preserve type source info. 1718 QualType T = GetTypeFromParser(DS.getTypeRep()); 1719 EnterDeclaratorContext(S, DC); 1720 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1721 ExitDeclaratorContext(S); 1722 if (T.isNull()) 1723 return DeclPtrTy(); 1724 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1725 } 1726 } 1727 1728 DeclContext *DC; 1729 NamedDecl *PrevDecl; 1730 NamedDecl *New; 1731 1732 DeclaratorInfo *DInfo = 0; 1733 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1734 1735 // See if this is a redefinition of a variable in the same scope. 1736 if (D.getCXXScopeSpec().isInvalid()) { 1737 DC = CurContext; 1738 PrevDecl = 0; 1739 D.setInvalidType(); 1740 } else if (!D.getCXXScopeSpec().isSet()) { 1741 LookupNameKind NameKind = LookupOrdinaryName; 1742 1743 // If the declaration we're planning to build will be a function 1744 // or object with linkage, then look for another declaration with 1745 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1746 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1747 /* Do nothing*/; 1748 else if (R->isFunctionType()) { 1749 if (CurContext->isFunctionOrMethod() || 1750 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1751 NameKind = LookupRedeclarationWithLinkage; 1752 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1753 NameKind = LookupRedeclarationWithLinkage; 1754 else if (CurContext->getLookupContext()->isTranslationUnit() && 1755 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1756 NameKind = LookupRedeclarationWithLinkage; 1757 1758 DC = CurContext; 1759 LookupResult R; 1760 LookupName(R, S, Name, NameKind, true, 1761 NameKind == LookupRedeclarationWithLinkage, 1762 D.getIdentifierLoc()); 1763 PrevDecl = R.getAsSingleDecl(Context); 1764 } else { // Something like "int foo::x;" 1765 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1766 1767 if (!DC) { 1768 // If we could not compute the declaration context, it's because the 1769 // declaration context is dependent but does not refer to a class, 1770 // class template, or class template partial specialization. Complain 1771 // and return early, to avoid the coming semantic disaster. 1772 Diag(D.getIdentifierLoc(), 1773 diag::err_template_qualified_declarator_no_match) 1774 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1775 << D.getCXXScopeSpec().getRange(); 1776 return DeclPtrTy(); 1777 } 1778 1779 if (!DC->isDependentContext() && 1780 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1781 return DeclPtrTy(); 1782 1783 LookupResult Res; 1784 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1785 PrevDecl = Res.getAsSingleDecl(Context); 1786 1787 // C++ 7.3.1.2p2: 1788 // Members (including explicit specializations of templates) of a named 1789 // namespace can also be defined outside that namespace by explicit 1790 // qualification of the name being defined, provided that the entity being 1791 // defined was already declared in the namespace and the definition appears 1792 // after the point of declaration in a namespace that encloses the 1793 // declarations namespace. 1794 // 1795 // Note that we only check the context at this point. We don't yet 1796 // have enough information to make sure that PrevDecl is actually 1797 // the declaration we want to match. For example, given: 1798 // 1799 // class X { 1800 // void f(); 1801 // void f(float); 1802 // }; 1803 // 1804 // void X::f(int) { } // ill-formed 1805 // 1806 // In this case, PrevDecl will point to the overload set 1807 // containing the two f's declared in X, but neither of them 1808 // matches. 1809 1810 // First check whether we named the global scope. 1811 if (isa<TranslationUnitDecl>(DC)) { 1812 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1813 << Name << D.getCXXScopeSpec().getRange(); 1814 } else if (!CurContext->Encloses(DC)) { 1815 // The qualifying scope doesn't enclose the original declaration. 1816 // Emit diagnostic based on current scope. 1817 SourceLocation L = D.getIdentifierLoc(); 1818 SourceRange R = D.getCXXScopeSpec().getRange(); 1819 if (isa<FunctionDecl>(CurContext)) 1820 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1821 else 1822 Diag(L, diag::err_invalid_declarator_scope) 1823 << Name << cast<NamedDecl>(DC) << R; 1824 D.setInvalidType(); 1825 } 1826 } 1827 1828 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1829 // Maybe we will complain about the shadowed template parameter. 1830 if (!D.isInvalidType()) 1831 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1832 D.setInvalidType(); 1833 1834 // Just pretend that we didn't see the previous declaration. 1835 PrevDecl = 0; 1836 } 1837 1838 // In C++, the previous declaration we find might be a tag type 1839 // (class or enum). In this case, the new declaration will hide the 1840 // tag type. Note that this does does not apply if we're declaring a 1841 // typedef (C++ [dcl.typedef]p4). 1842 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1843 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1844 PrevDecl = 0; 1845 1846 bool Redeclaration = false; 1847 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1848 if (TemplateParamLists.size()) { 1849 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1850 return DeclPtrTy(); 1851 } 1852 1853 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1854 } else if (R->isFunctionType()) { 1855 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1856 move(TemplateParamLists), 1857 IsFunctionDefinition, Redeclaration); 1858 } else { 1859 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1860 move(TemplateParamLists), 1861 Redeclaration); 1862 } 1863 1864 if (New == 0) 1865 return DeclPtrTy(); 1866 1867 // If this has an identifier and is not an invalid redeclaration or 1868 // function template specialization, add it to the scope stack. 1869 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1870 !(isa<FunctionDecl>(New) && 1871 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1872 PushOnScopeChains(New, S); 1873 1874 return DeclPtrTy::make(New); 1875} 1876 1877/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1878/// types into constant array types in certain situations which would otherwise 1879/// be errors (for GCC compatibility). 1880static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1881 ASTContext &Context, 1882 bool &SizeIsNegative) { 1883 // This method tries to turn a variable array into a constant 1884 // array even when the size isn't an ICE. This is necessary 1885 // for compatibility with code that depends on gcc's buggy 1886 // constant expression folding, like struct {char x[(int)(char*)2];} 1887 SizeIsNegative = false; 1888 1889 QualifierCollector Qs; 1890 const Type *Ty = Qs.strip(T); 1891 1892 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1893 QualType Pointee = PTy->getPointeeType(); 1894 QualType FixedType = 1895 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1896 if (FixedType.isNull()) return FixedType; 1897 FixedType = Context.getPointerType(FixedType); 1898 return Qs.apply(FixedType); 1899 } 1900 1901 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1902 if (!VLATy) 1903 return QualType(); 1904 // FIXME: We should probably handle this case 1905 if (VLATy->getElementType()->isVariablyModifiedType()) 1906 return QualType(); 1907 1908 Expr::EvalResult EvalResult; 1909 if (!VLATy->getSizeExpr() || 1910 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1911 !EvalResult.Val.isInt()) 1912 return QualType(); 1913 1914 llvm::APSInt &Res = EvalResult.Val.getInt(); 1915 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1916 // TODO: preserve the size expression in declarator info 1917 return Context.getConstantArrayType(VLATy->getElementType(), 1918 Res, ArrayType::Normal, 0); 1919 } 1920 1921 SizeIsNegative = true; 1922 return QualType(); 1923} 1924 1925/// \brief Register the given locally-scoped external C declaration so 1926/// that it can be found later for redeclarations 1927void 1928Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1929 Scope *S) { 1930 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1931 "Decl is not a locally-scoped decl!"); 1932 // Note that we have a locally-scoped external with this name. 1933 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1934 1935 if (!PrevDecl) 1936 return; 1937 1938 // If there was a previous declaration of this variable, it may be 1939 // in our identifier chain. Update the identifier chain with the new 1940 // declaration. 1941 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1942 // The previous declaration was found on the identifer resolver 1943 // chain, so remove it from its scope. 1944 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1945 S = S->getParent(); 1946 1947 if (S) 1948 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1949 } 1950} 1951 1952/// \brief Diagnose function specifiers on a declaration of an identifier that 1953/// does not identify a function. 1954void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1955 // FIXME: We should probably indicate the identifier in question to avoid 1956 // confusion for constructs like "inline int a(), b;" 1957 if (D.getDeclSpec().isInlineSpecified()) 1958 Diag(D.getDeclSpec().getInlineSpecLoc(), 1959 diag::err_inline_non_function); 1960 1961 if (D.getDeclSpec().isVirtualSpecified()) 1962 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1963 diag::err_virtual_non_function); 1964 1965 if (D.getDeclSpec().isExplicitSpecified()) 1966 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1967 diag::err_explicit_non_function); 1968} 1969 1970NamedDecl* 1971Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1972 QualType R, DeclaratorInfo *DInfo, 1973 NamedDecl* PrevDecl, bool &Redeclaration) { 1974 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1975 if (D.getCXXScopeSpec().isSet()) { 1976 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1977 << D.getCXXScopeSpec().getRange(); 1978 D.setInvalidType(); 1979 // Pretend we didn't see the scope specifier. 1980 DC = 0; 1981 } 1982 1983 if (getLangOptions().CPlusPlus) { 1984 // Check that there are no default arguments (C++ only). 1985 CheckExtraCXXDefaultArguments(D); 1986 } 1987 1988 DiagnoseFunctionSpecifiers(D); 1989 1990 if (D.getDeclSpec().isThreadSpecified()) 1991 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1992 1993 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 1994 if (!NewTD) return 0; 1995 1996 // Handle attributes prior to checking for duplicates in MergeVarDecl 1997 ProcessDeclAttributes(S, NewTD, D); 1998 // Merge the decl with the existing one if appropriate. If the decl is 1999 // in an outer scope, it isn't the same thing. 2000 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2001 Redeclaration = true; 2002 MergeTypeDefDecl(NewTD, PrevDecl); 2003 } 2004 2005 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2006 // then it shall have block scope. 2007 QualType T = NewTD->getUnderlyingType(); 2008 if (T->isVariablyModifiedType()) { 2009 CurFunctionNeedsScopeChecking = true; 2010 2011 if (S->getFnParent() == 0) { 2012 bool SizeIsNegative; 2013 QualType FixedTy = 2014 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2015 if (!FixedTy.isNull()) { 2016 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2017 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2018 } else { 2019 if (SizeIsNegative) 2020 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2021 else if (T->isVariableArrayType()) 2022 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2023 else 2024 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2025 NewTD->setInvalidDecl(); 2026 } 2027 } 2028 } 2029 2030 // If this is the C FILE type, notify the AST context. 2031 if (IdentifierInfo *II = NewTD->getIdentifier()) 2032 if (!NewTD->isInvalidDecl() && 2033 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2034 if (II->isStr("FILE")) 2035 Context.setFILEDecl(NewTD); 2036 else if (II->isStr("jmp_buf")) 2037 Context.setjmp_bufDecl(NewTD); 2038 else if (II->isStr("sigjmp_buf")) 2039 Context.setsigjmp_bufDecl(NewTD); 2040 } 2041 2042 return NewTD; 2043} 2044 2045/// \brief Determines whether the given declaration is an out-of-scope 2046/// previous declaration. 2047/// 2048/// This routine should be invoked when name lookup has found a 2049/// previous declaration (PrevDecl) that is not in the scope where a 2050/// new declaration by the same name is being introduced. If the new 2051/// declaration occurs in a local scope, previous declarations with 2052/// linkage may still be considered previous declarations (C99 2053/// 6.2.2p4-5, C++ [basic.link]p6). 2054/// 2055/// \param PrevDecl the previous declaration found by name 2056/// lookup 2057/// 2058/// \param DC the context in which the new declaration is being 2059/// declared. 2060/// 2061/// \returns true if PrevDecl is an out-of-scope previous declaration 2062/// for a new delcaration with the same name. 2063static bool 2064isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2065 ASTContext &Context) { 2066 if (!PrevDecl) 2067 return 0; 2068 2069 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2070 // case we need to check each of the overloaded functions. 2071 if (!PrevDecl->hasLinkage()) 2072 return false; 2073 2074 if (Context.getLangOptions().CPlusPlus) { 2075 // C++ [basic.link]p6: 2076 // If there is a visible declaration of an entity with linkage 2077 // having the same name and type, ignoring entities declared 2078 // outside the innermost enclosing namespace scope, the block 2079 // scope declaration declares that same entity and receives the 2080 // linkage of the previous declaration. 2081 DeclContext *OuterContext = DC->getLookupContext(); 2082 if (!OuterContext->isFunctionOrMethod()) 2083 // This rule only applies to block-scope declarations. 2084 return false; 2085 else { 2086 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2087 if (PrevOuterContext->isRecord()) 2088 // We found a member function: ignore it. 2089 return false; 2090 else { 2091 // Find the innermost enclosing namespace for the new and 2092 // previous declarations. 2093 while (!OuterContext->isFileContext()) 2094 OuterContext = OuterContext->getParent(); 2095 while (!PrevOuterContext->isFileContext()) 2096 PrevOuterContext = PrevOuterContext->getParent(); 2097 2098 // The previous declaration is in a different namespace, so it 2099 // isn't the same function. 2100 if (OuterContext->getPrimaryContext() != 2101 PrevOuterContext->getPrimaryContext()) 2102 return false; 2103 } 2104 } 2105 } 2106 2107 return true; 2108} 2109 2110NamedDecl* 2111Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2112 QualType R, DeclaratorInfo *DInfo, 2113 NamedDecl* PrevDecl, 2114 MultiTemplateParamsArg TemplateParamLists, 2115 bool &Redeclaration) { 2116 DeclarationName Name = GetNameForDeclarator(D); 2117 2118 // Check that there are no default arguments (C++ only). 2119 if (getLangOptions().CPlusPlus) 2120 CheckExtraCXXDefaultArguments(D); 2121 2122 VarDecl *NewVD; 2123 VarDecl::StorageClass SC; 2124 switch (D.getDeclSpec().getStorageClassSpec()) { 2125 default: assert(0 && "Unknown storage class!"); 2126 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2127 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2128 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2129 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2130 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2131 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2132 case DeclSpec::SCS_mutable: 2133 // mutable can only appear on non-static class members, so it's always 2134 // an error here 2135 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2136 D.setInvalidType(); 2137 SC = VarDecl::None; 2138 break; 2139 } 2140 2141 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2142 if (!II) { 2143 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2144 << Name.getAsString(); 2145 return 0; 2146 } 2147 2148 DiagnoseFunctionSpecifiers(D); 2149 2150 if (!DC->isRecord() && S->getFnParent() == 0) { 2151 // C99 6.9p2: The storage-class specifiers auto and register shall not 2152 // appear in the declaration specifiers in an external declaration. 2153 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2154 2155 // If this is a register variable with an asm label specified, then this 2156 // is a GNU extension. 2157 if (SC == VarDecl::Register && D.getAsmLabel()) 2158 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2159 else 2160 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2161 D.setInvalidType(); 2162 } 2163 } 2164 if (DC->isRecord() && !CurContext->isRecord()) { 2165 // This is an out-of-line definition of a static data member. 2166 if (SC == VarDecl::Static) { 2167 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2168 diag::err_static_out_of_line) 2169 << CodeModificationHint::CreateRemoval( 2170 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2171 } else if (SC == VarDecl::None) 2172 SC = VarDecl::Static; 2173 } 2174 if (SC == VarDecl::Static) { 2175 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2176 if (RD->isLocalClass()) 2177 Diag(D.getIdentifierLoc(), 2178 diag::err_static_data_member_not_allowed_in_local_class) 2179 << Name << RD->getDeclName(); 2180 } 2181 } 2182 2183 // Match up the template parameter lists with the scope specifier, then 2184 // determine whether we have a template or a template specialization. 2185 bool isExplicitSpecialization = false; 2186 if (TemplateParameterList *TemplateParams 2187 = MatchTemplateParametersToScopeSpecifier( 2188 D.getDeclSpec().getSourceRange().getBegin(), 2189 D.getCXXScopeSpec(), 2190 (TemplateParameterList**)TemplateParamLists.get(), 2191 TemplateParamLists.size(), 2192 isExplicitSpecialization)) { 2193 if (TemplateParams->size() > 0) { 2194 // There is no such thing as a variable template. 2195 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2196 << II 2197 << SourceRange(TemplateParams->getTemplateLoc(), 2198 TemplateParams->getRAngleLoc()); 2199 return 0; 2200 } else { 2201 // There is an extraneous 'template<>' for this variable. Complain 2202 // about it, but allow the declaration of the variable. 2203 Diag(TemplateParams->getTemplateLoc(), 2204 diag::err_template_variable_noparams) 2205 << II 2206 << SourceRange(TemplateParams->getTemplateLoc(), 2207 TemplateParams->getRAngleLoc()); 2208 2209 isExplicitSpecialization = true; 2210 } 2211 } 2212 2213 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2214 II, R, DInfo, SC); 2215 2216 if (D.isInvalidType()) 2217 NewVD->setInvalidDecl(); 2218 2219 if (D.getDeclSpec().isThreadSpecified()) { 2220 if (NewVD->hasLocalStorage()) 2221 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2222 else if (!Context.Target.isTLSSupported()) 2223 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2224 else 2225 NewVD->setThreadSpecified(true); 2226 } 2227 2228 // Set the lexical context. If the declarator has a C++ scope specifier, the 2229 // lexical context will be different from the semantic context. 2230 NewVD->setLexicalDeclContext(CurContext); 2231 2232 // Handle attributes prior to checking for duplicates in MergeVarDecl 2233 ProcessDeclAttributes(S, NewVD, D); 2234 2235 // Handle GNU asm-label extension (encoded as an attribute). 2236 if (Expr *E = (Expr*) D.getAsmLabel()) { 2237 // The parser guarantees this is a string. 2238 StringLiteral *SE = cast<StringLiteral>(E); 2239 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2240 SE->getByteLength()))); 2241 } 2242 2243 // If name lookup finds a previous declaration that is not in the 2244 // same scope as the new declaration, this may still be an 2245 // acceptable redeclaration. 2246 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2247 !(NewVD->hasLinkage() && 2248 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2249 PrevDecl = 0; 2250 2251 // Merge the decl with the existing one if appropriate. 2252 if (PrevDecl) { 2253 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2254 // The user tried to define a non-static data member 2255 // out-of-line (C++ [dcl.meaning]p1). 2256 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2257 << D.getCXXScopeSpec().getRange(); 2258 PrevDecl = 0; 2259 NewVD->setInvalidDecl(); 2260 } 2261 } else if (D.getCXXScopeSpec().isSet()) { 2262 // No previous declaration in the qualifying scope. 2263 Diag(D.getIdentifierLoc(), diag::err_no_member) 2264 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2265 << D.getCXXScopeSpec().getRange(); 2266 NewVD->setInvalidDecl(); 2267 } 2268 2269 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2270 2271 // This is an explicit specialization of a static data member. Check it. 2272 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2273 CheckMemberSpecialization(NewVD, PrevDecl)) 2274 NewVD->setInvalidDecl(); 2275 2276 // attributes declared post-definition are currently ignored 2277 if (PrevDecl) { 2278 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2279 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2280 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2281 Diag(Def->getLocation(), diag::note_previous_definition); 2282 } 2283 } 2284 2285 // If this is a locally-scoped extern C variable, update the map of 2286 // such variables. 2287 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2288 !NewVD->isInvalidDecl()) 2289 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2290 2291 return NewVD; 2292} 2293 2294/// \brief Perform semantic checking on a newly-created variable 2295/// declaration. 2296/// 2297/// This routine performs all of the type-checking required for a 2298/// variable declaration once it has been built. It is used both to 2299/// check variables after they have been parsed and their declarators 2300/// have been translated into a declaration, and to check variables 2301/// that have been instantiated from a template. 2302/// 2303/// Sets NewVD->isInvalidDecl() if an error was encountered. 2304void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2305 bool &Redeclaration) { 2306 // If the decl is already known invalid, don't check it. 2307 if (NewVD->isInvalidDecl()) 2308 return; 2309 2310 QualType T = NewVD->getType(); 2311 2312 if (T->isObjCInterfaceType()) { 2313 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2314 return NewVD->setInvalidDecl(); 2315 } 2316 2317 // The variable can not have an abstract class type. 2318 if (RequireNonAbstractType(NewVD->getLocation(), T, 2319 diag::err_abstract_type_in_decl, 2320 AbstractVariableType)) 2321 return NewVD->setInvalidDecl(); 2322 2323 // Emit an error if an address space was applied to decl with local storage. 2324 // This includes arrays of objects with address space qualifiers, but not 2325 // automatic variables that point to other address spaces. 2326 // ISO/IEC TR 18037 S5.1.2 2327 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2328 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2329 return NewVD->setInvalidDecl(); 2330 } 2331 2332 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2333 && !NewVD->hasAttr<BlocksAttr>()) 2334 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2335 2336 bool isVM = T->isVariablyModifiedType(); 2337 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2338 NewVD->hasAttr<BlocksAttr>()) 2339 CurFunctionNeedsScopeChecking = true; 2340 2341 if ((isVM && NewVD->hasLinkage()) || 2342 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2343 bool SizeIsNegative; 2344 QualType FixedTy = 2345 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2346 2347 if (FixedTy.isNull() && T->isVariableArrayType()) { 2348 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2349 // FIXME: This won't give the correct result for 2350 // int a[10][n]; 2351 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2352 2353 if (NewVD->isFileVarDecl()) 2354 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2355 << SizeRange; 2356 else if (NewVD->getStorageClass() == VarDecl::Static) 2357 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2358 << SizeRange; 2359 else 2360 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2361 << SizeRange; 2362 return NewVD->setInvalidDecl(); 2363 } 2364 2365 if (FixedTy.isNull()) { 2366 if (NewVD->isFileVarDecl()) 2367 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2368 else 2369 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2370 return NewVD->setInvalidDecl(); 2371 } 2372 2373 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2374 NewVD->setType(FixedTy); 2375 } 2376 2377 if (!PrevDecl && NewVD->isExternC()) { 2378 // Since we did not find anything by this name and we're declaring 2379 // an extern "C" variable, look for a non-visible extern "C" 2380 // declaration with the same name. 2381 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2382 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2383 if (Pos != LocallyScopedExternalDecls.end()) 2384 PrevDecl = Pos->second; 2385 } 2386 2387 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2388 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2389 << T; 2390 return NewVD->setInvalidDecl(); 2391 } 2392 2393 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2394 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2395 return NewVD->setInvalidDecl(); 2396 } 2397 2398 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2399 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2400 return NewVD->setInvalidDecl(); 2401 } 2402 2403 if (PrevDecl) { 2404 Redeclaration = true; 2405 MergeVarDecl(NewVD, PrevDecl); 2406 } 2407} 2408 2409static bool isUsingDecl(Decl *D) { 2410 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2411} 2412 2413/// \brief Data used with FindOverriddenMethod 2414struct FindOverriddenMethodData { 2415 Sema *S; 2416 CXXMethodDecl *Method; 2417}; 2418 2419/// \brief Member lookup function that determines whether a given C++ 2420/// method overrides a method in a base class, to be used with 2421/// CXXRecordDecl::lookupInBases(). 2422static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2423 CXXBasePath &Path, 2424 void *UserData) { 2425 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2426 2427 FindOverriddenMethodData *Data 2428 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2429 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2430 Path.Decls.first != Path.Decls.second; 2431 ++Path.Decls.first) { 2432 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2433 OverloadedFunctionDecl::function_iterator MatchedDecl; 2434 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2435 return true; 2436 } 2437 } 2438 2439 return false; 2440} 2441 2442NamedDecl* 2443Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2444 QualType R, DeclaratorInfo *DInfo, 2445 NamedDecl* PrevDecl, 2446 MultiTemplateParamsArg TemplateParamLists, 2447 bool IsFunctionDefinition, bool &Redeclaration) { 2448 assert(R.getTypePtr()->isFunctionType()); 2449 2450 DeclarationName Name = GetNameForDeclarator(D); 2451 FunctionDecl::StorageClass SC = FunctionDecl::None; 2452 switch (D.getDeclSpec().getStorageClassSpec()) { 2453 default: assert(0 && "Unknown storage class!"); 2454 case DeclSpec::SCS_auto: 2455 case DeclSpec::SCS_register: 2456 case DeclSpec::SCS_mutable: 2457 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2458 diag::err_typecheck_sclass_func); 2459 D.setInvalidType(); 2460 break; 2461 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2462 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2463 case DeclSpec::SCS_static: { 2464 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2465 // C99 6.7.1p5: 2466 // The declaration of an identifier for a function that has 2467 // block scope shall have no explicit storage-class specifier 2468 // other than extern 2469 // See also (C++ [dcl.stc]p4). 2470 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2471 diag::err_static_block_func); 2472 SC = FunctionDecl::None; 2473 } else 2474 SC = FunctionDecl::Static; 2475 break; 2476 } 2477 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2478 } 2479 2480 if (D.getDeclSpec().isThreadSpecified()) 2481 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2482 2483 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2484 bool isInline = D.getDeclSpec().isInlineSpecified(); 2485 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2486 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2487 2488 // Check that the return type is not an abstract class type. 2489 // For record types, this is done by the AbstractClassUsageDiagnoser once 2490 // the class has been completely parsed. 2491 if (!DC->isRecord() && 2492 RequireNonAbstractType(D.getIdentifierLoc(), 2493 R->getAs<FunctionType>()->getResultType(), 2494 diag::err_abstract_type_in_decl, 2495 AbstractReturnType)) 2496 D.setInvalidType(); 2497 2498 // Do not allow returning a objc interface by-value. 2499 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2500 Diag(D.getIdentifierLoc(), 2501 diag::err_object_cannot_be_passed_returned_by_value) << 0 2502 << R->getAs<FunctionType>()->getResultType(); 2503 D.setInvalidType(); 2504 } 2505 2506 bool isVirtualOkay = false; 2507 FunctionDecl *NewFD; 2508 2509 if (isFriend) { 2510 // DC is the namespace in which the function is being declared. 2511 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2512 "friend function being created in a non-namespace context"); 2513 2514 // C++ [class.friend]p5 2515 // A function can be defined in a friend declaration of a 2516 // class . . . . Such a function is implicitly inline. 2517 isInline |= IsFunctionDefinition; 2518 } 2519 2520 if (D.getKind() == Declarator::DK_Constructor) { 2521 // This is a C++ constructor declaration. 2522 assert(DC->isRecord() && 2523 "Constructors can only be declared in a member context"); 2524 2525 R = CheckConstructorDeclarator(D, R, SC); 2526 2527 // Create the new declaration 2528 NewFD = CXXConstructorDecl::Create(Context, 2529 cast<CXXRecordDecl>(DC), 2530 D.getIdentifierLoc(), Name, R, DInfo, 2531 isExplicit, isInline, 2532 /*isImplicitlyDeclared=*/false); 2533 } else if (D.getKind() == Declarator::DK_Destructor) { 2534 // This is a C++ destructor declaration. 2535 if (DC->isRecord()) { 2536 R = CheckDestructorDeclarator(D, SC); 2537 2538 NewFD = CXXDestructorDecl::Create(Context, 2539 cast<CXXRecordDecl>(DC), 2540 D.getIdentifierLoc(), Name, R, 2541 isInline, 2542 /*isImplicitlyDeclared=*/false); 2543 2544 isVirtualOkay = true; 2545 } else { 2546 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2547 2548 // Create a FunctionDecl to satisfy the function definition parsing 2549 // code path. 2550 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2551 Name, R, DInfo, SC, isInline, 2552 /*hasPrototype=*/true); 2553 D.setInvalidType(); 2554 } 2555 } else if (D.getKind() == Declarator::DK_Conversion) { 2556 if (!DC->isRecord()) { 2557 Diag(D.getIdentifierLoc(), 2558 diag::err_conv_function_not_member); 2559 return 0; 2560 } 2561 2562 CheckConversionDeclarator(D, R, SC); 2563 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2564 D.getIdentifierLoc(), Name, R, DInfo, 2565 isInline, isExplicit); 2566 2567 isVirtualOkay = true; 2568 } else if (DC->isRecord()) { 2569 // If the of the function is the same as the name of the record, then this 2570 // must be an invalid constructor that has a return type. 2571 // (The parser checks for a return type and makes the declarator a 2572 // constructor if it has no return type). 2573 // must have an invalid constructor that has a return type 2574 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2575 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2576 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2577 << SourceRange(D.getIdentifierLoc()); 2578 return 0; 2579 } 2580 2581 // This is a C++ method declaration. 2582 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2583 D.getIdentifierLoc(), Name, R, DInfo, 2584 (SC == FunctionDecl::Static), isInline); 2585 2586 isVirtualOkay = (SC != FunctionDecl::Static); 2587 } else { 2588 // Determine whether the function was written with a 2589 // prototype. This true when: 2590 // - we're in C++ (where every function has a prototype), 2591 // - there is a prototype in the declarator, or 2592 // - the type R of the function is some kind of typedef or other reference 2593 // to a type name (which eventually refers to a function type). 2594 bool HasPrototype = 2595 getLangOptions().CPlusPlus || 2596 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2597 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2598 2599 NewFD = FunctionDecl::Create(Context, DC, 2600 D.getIdentifierLoc(), 2601 Name, R, DInfo, SC, isInline, HasPrototype); 2602 } 2603 2604 if (D.isInvalidType()) 2605 NewFD->setInvalidDecl(); 2606 2607 // Set the lexical context. If the declarator has a C++ 2608 // scope specifier, or is the object of a friend declaration, the 2609 // lexical context will be different from the semantic context. 2610 NewFD->setLexicalDeclContext(CurContext); 2611 2612 // Match up the template parameter lists with the scope specifier, then 2613 // determine whether we have a template or a template specialization. 2614 FunctionTemplateDecl *FunctionTemplate = 0; 2615 bool isExplicitSpecialization = false; 2616 bool isFunctionTemplateSpecialization = false; 2617 if (TemplateParameterList *TemplateParams 2618 = MatchTemplateParametersToScopeSpecifier( 2619 D.getDeclSpec().getSourceRange().getBegin(), 2620 D.getCXXScopeSpec(), 2621 (TemplateParameterList**)TemplateParamLists.get(), 2622 TemplateParamLists.size(), 2623 isExplicitSpecialization)) { 2624 if (TemplateParams->size() > 0) { 2625 // This is a function template 2626 2627 // Check that we can declare a template here. 2628 if (CheckTemplateDeclScope(S, TemplateParams)) 2629 return 0; 2630 2631 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2632 NewFD->getLocation(), 2633 Name, TemplateParams, 2634 NewFD); 2635 FunctionTemplate->setLexicalDeclContext(CurContext); 2636 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2637 } else { 2638 // This is a function template specialization. 2639 isFunctionTemplateSpecialization = true; 2640 } 2641 2642 // FIXME: Free this memory properly. 2643 TemplateParamLists.release(); 2644 } 2645 2646 // C++ [dcl.fct.spec]p5: 2647 // The virtual specifier shall only be used in declarations of 2648 // nonstatic class member functions that appear within a 2649 // member-specification of a class declaration; see 10.3. 2650 // 2651 if (isVirtual && !NewFD->isInvalidDecl()) { 2652 if (!isVirtualOkay) { 2653 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2654 diag::err_virtual_non_function); 2655 } else if (!CurContext->isRecord()) { 2656 // 'virtual' was specified outside of the class. 2657 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2658 << CodeModificationHint::CreateRemoval( 2659 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2660 } else { 2661 // Okay: Add virtual to the method. 2662 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2663 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2664 CurClass->setAggregate(false); 2665 CurClass->setPOD(false); 2666 CurClass->setEmpty(false); 2667 CurClass->setPolymorphic(true); 2668 CurClass->setHasTrivialConstructor(false); 2669 CurClass->setHasTrivialCopyConstructor(false); 2670 CurClass->setHasTrivialCopyAssignment(false); 2671 } 2672 } 2673 2674 if (isFriend) { 2675 if (FunctionTemplate) { 2676 FunctionTemplate->setObjectOfFriendDecl( 2677 /* PreviouslyDeclared= */ PrevDecl != NULL); 2678 FunctionTemplate->setAccess(AS_public); 2679 } 2680 else 2681 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2682 2683 NewFD->setAccess(AS_public); 2684 } 2685 2686 2687 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2688 // Look for virtual methods in base classes that this method might override. 2689 CXXBasePaths Paths; 2690 FindOverriddenMethodData Data; 2691 Data.Method = NewMD; 2692 Data.S = this; 2693 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2694 Paths)) { 2695 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2696 E = Paths.found_decls_end(); I != E; ++I) { 2697 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2698 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2699 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2700 NewMD->addOverriddenMethod(OldMD); 2701 } 2702 } 2703 } 2704 } 2705 2706 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2707 !CurContext->isRecord()) { 2708 // C++ [class.static]p1: 2709 // A data or function member of a class may be declared static 2710 // in a class definition, in which case it is a static member of 2711 // the class. 2712 2713 // Complain about the 'static' specifier if it's on an out-of-line 2714 // member function definition. 2715 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2716 diag::err_static_out_of_line) 2717 << CodeModificationHint::CreateRemoval( 2718 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2719 } 2720 2721 // Handle GNU asm-label extension (encoded as an attribute). 2722 if (Expr *E = (Expr*) D.getAsmLabel()) { 2723 // The parser guarantees this is a string. 2724 StringLiteral *SE = cast<StringLiteral>(E); 2725 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2726 SE->getByteLength()))); 2727 } 2728 2729 // Copy the parameter declarations from the declarator D to the function 2730 // declaration NewFD, if they are available. First scavenge them into Params. 2731 llvm::SmallVector<ParmVarDecl*, 16> Params; 2732 if (D.getNumTypeObjects() > 0) { 2733 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2734 2735 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2736 // function that takes no arguments, not a function that takes a 2737 // single void argument. 2738 // We let through "const void" here because Sema::GetTypeForDeclarator 2739 // already checks for that case. 2740 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2741 FTI.ArgInfo[0].Param && 2742 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2743 // Empty arg list, don't push any params. 2744 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2745 2746 // In C++, the empty parameter-type-list must be spelled "void"; a 2747 // typedef of void is not permitted. 2748 if (getLangOptions().CPlusPlus && 2749 Param->getType().getUnqualifiedType() != Context.VoidTy) 2750 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2751 // FIXME: Leaks decl? 2752 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2753 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2754 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2755 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2756 Param->setDeclContext(NewFD); 2757 Params.push_back(Param); 2758 } 2759 } 2760 2761 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2762 // When we're declaring a function with a typedef, typeof, etc as in the 2763 // following example, we'll need to synthesize (unnamed) 2764 // parameters for use in the declaration. 2765 // 2766 // @code 2767 // typedef void fn(int); 2768 // fn f; 2769 // @endcode 2770 2771 // Synthesize a parameter for each argument type. 2772 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2773 AE = FT->arg_type_end(); AI != AE; ++AI) { 2774 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2775 SourceLocation(), 0, 2776 *AI, /*DInfo=*/0, 2777 VarDecl::None, 0); 2778 Param->setImplicit(); 2779 Params.push_back(Param); 2780 } 2781 } else { 2782 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2783 "Should not need args for typedef of non-prototype fn"); 2784 } 2785 // Finally, we know we have the right number of parameters, install them. 2786 NewFD->setParams(Context, Params.data(), Params.size()); 2787 2788 // If name lookup finds a previous declaration that is not in the 2789 // same scope as the new declaration, this may still be an 2790 // acceptable redeclaration. 2791 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2792 !(NewFD->hasLinkage() && 2793 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2794 PrevDecl = 0; 2795 2796 // If the declarator is a template-id, translate the parser's template 2797 // argument list into our AST format. 2798 bool HasExplicitTemplateArgs = false; 2799 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2800 SourceLocation LAngleLoc, RAngleLoc; 2801 if (D.getKind() == Declarator::DK_TemplateId) { 2802 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2803 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2804 TemplateId->getTemplateArgs(), 2805 TemplateId->getTemplateArgIsType(), 2806 TemplateId->NumArgs); 2807 translateTemplateArguments(TemplateArgsPtr, 2808 TemplateId->getTemplateArgLocations(), 2809 TemplateArgs); 2810 TemplateArgsPtr.release(); 2811 2812 HasExplicitTemplateArgs = true; 2813 LAngleLoc = TemplateId->LAngleLoc; 2814 RAngleLoc = TemplateId->RAngleLoc; 2815 2816 if (FunctionTemplate) { 2817 // FIXME: Diagnose function template with explicit template 2818 // arguments. 2819 HasExplicitTemplateArgs = false; 2820 } else if (!isFunctionTemplateSpecialization && 2821 !D.getDeclSpec().isFriendSpecified()) { 2822 // We have encountered something that the user meant to be a 2823 // specialization (because it has explicitly-specified template 2824 // arguments) but that was not introduced with a "template<>" (or had 2825 // too few of them). 2826 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2827 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2828 << CodeModificationHint::CreateInsertion( 2829 D.getDeclSpec().getSourceRange().getBegin(), 2830 "template<> "); 2831 isFunctionTemplateSpecialization = true; 2832 } 2833 } 2834 2835 if (isFunctionTemplateSpecialization) { 2836 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2837 LAngleLoc, TemplateArgs.data(), 2838 TemplateArgs.size(), RAngleLoc, 2839 PrevDecl)) 2840 NewFD->setInvalidDecl(); 2841 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2842 CheckMemberSpecialization(NewFD, PrevDecl)) 2843 NewFD->setInvalidDecl(); 2844 2845 // Perform semantic checking on the function declaration. 2846 bool OverloadableAttrRequired = false; // FIXME: HACK! 2847 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2848 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2849 2850 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2851 // An out-of-line member function declaration must also be a 2852 // definition (C++ [dcl.meaning]p1). 2853 // Note that this is not the case for explicit specializations of 2854 // function templates or member functions of class templates, per 2855 // C++ [temp.expl.spec]p2. 2856 if (!IsFunctionDefinition && !isFriend && 2857 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2858 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2859 << D.getCXXScopeSpec().getRange(); 2860 NewFD->setInvalidDecl(); 2861 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2862 // The user tried to provide an out-of-line definition for a 2863 // function that is a member of a class or namespace, but there 2864 // was no such member function declared (C++ [class.mfct]p2, 2865 // C++ [namespace.memdef]p2). For example: 2866 // 2867 // class X { 2868 // void f() const; 2869 // }; 2870 // 2871 // void X::f() { } // ill-formed 2872 // 2873 // Complain about this problem, and attempt to suggest close 2874 // matches (e.g., those that differ only in cv-qualifiers and 2875 // whether the parameter types are references). 2876 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2877 << Name << DC << D.getCXXScopeSpec().getRange(); 2878 NewFD->setInvalidDecl(); 2879 2880 LookupResult Prev; 2881 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2882 assert(!Prev.isAmbiguous() && 2883 "Cannot have an ambiguity in previous-declaration lookup"); 2884 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2885 Func != FuncEnd; ++Func) { 2886 if (isa<FunctionDecl>(*Func) && 2887 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2888 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2889 } 2890 2891 PrevDecl = 0; 2892 } 2893 } 2894 2895 // Handle attributes. We need to have merged decls when handling attributes 2896 // (for example to check for conflicts, etc). 2897 // FIXME: This needs to happen before we merge declarations. Then, 2898 // let attribute merging cope with attribute conflicts. 2899 ProcessDeclAttributes(S, NewFD, D); 2900 2901 // attributes declared post-definition are currently ignored 2902 if (Redeclaration && PrevDecl) { 2903 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2904 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2905 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2906 Diag(Def->getLocation(), diag::note_previous_definition); 2907 } 2908 } 2909 2910 AddKnownFunctionAttributes(NewFD); 2911 2912 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2913 // If a function name is overloadable in C, then every function 2914 // with that name must be marked "overloadable". 2915 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2916 << Redeclaration << NewFD; 2917 if (PrevDecl) 2918 Diag(PrevDecl->getLocation(), 2919 diag::note_attribute_overloadable_prev_overload); 2920 NewFD->addAttr(::new (Context) OverloadableAttr()); 2921 } 2922 2923 // If this is a locally-scoped extern C function, update the 2924 // map of such names. 2925 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2926 && !NewFD->isInvalidDecl()) 2927 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2928 2929 // Set this FunctionDecl's range up to the right paren. 2930 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2931 2932 if (FunctionTemplate && NewFD->isInvalidDecl()) 2933 FunctionTemplate->setInvalidDecl(); 2934 2935 if (FunctionTemplate) 2936 return FunctionTemplate; 2937 2938 return NewFD; 2939} 2940 2941/// \brief Perform semantic checking of a new function declaration. 2942/// 2943/// Performs semantic analysis of the new function declaration 2944/// NewFD. This routine performs all semantic checking that does not 2945/// require the actual declarator involved in the declaration, and is 2946/// used both for the declaration of functions as they are parsed 2947/// (called via ActOnDeclarator) and for the declaration of functions 2948/// that have been instantiated via C++ template instantiation (called 2949/// via InstantiateDecl). 2950/// 2951/// \param IsExplicitSpecialiation whether this new function declaration is 2952/// an explicit specialization of the previous declaration. 2953/// 2954/// This sets NewFD->isInvalidDecl() to true if there was an error. 2955void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2956 bool IsExplicitSpecialization, 2957 bool &Redeclaration, 2958 bool &OverloadableAttrRequired) { 2959 // If NewFD is already known erroneous, don't do any of this checking. 2960 if (NewFD->isInvalidDecl()) 2961 return; 2962 2963 if (NewFD->getResultType()->isVariablyModifiedType()) { 2964 // Functions returning a variably modified type violate C99 6.7.5.2p2 2965 // because all functions have linkage. 2966 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2967 return NewFD->setInvalidDecl(); 2968 } 2969 2970 if (NewFD->isMain()) 2971 CheckMain(NewFD); 2972 2973 // Check for a previous declaration of this name. 2974 if (!PrevDecl && NewFD->isExternC()) { 2975 // Since we did not find anything by this name and we're declaring 2976 // an extern "C" function, look for a non-visible extern "C" 2977 // declaration with the same name. 2978 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2979 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2980 if (Pos != LocallyScopedExternalDecls.end()) 2981 PrevDecl = Pos->second; 2982 } 2983 2984 // Merge or overload the declaration with an existing declaration of 2985 // the same name, if appropriate. 2986 if (PrevDecl) { 2987 // Determine whether NewFD is an overload of PrevDecl or 2988 // a declaration that requires merging. If it's an overload, 2989 // there's no more work to do here; we'll just add the new 2990 // function to the scope. 2991 OverloadedFunctionDecl::function_iterator MatchedDecl; 2992 2993 if (!getLangOptions().CPlusPlus && 2994 AllowOverloadingOfFunction(PrevDecl, Context)) { 2995 OverloadableAttrRequired = true; 2996 2997 // Functions marked "overloadable" must have a prototype (that 2998 // we can't get through declaration merging). 2999 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3000 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3001 << NewFD; 3002 Redeclaration = true; 3003 3004 // Turn this into a variadic function with no parameters. 3005 QualType R = Context.getFunctionType( 3006 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3007 0, 0, true, 0); 3008 NewFD->setType(R); 3009 return NewFD->setInvalidDecl(); 3010 } 3011 } 3012 3013 if (PrevDecl && 3014 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3015 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3016 Redeclaration = true; 3017 Decl *OldDecl = PrevDecl; 3018 3019 // If PrevDecl was an overloaded function, extract the 3020 // FunctionDecl that matched. 3021 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3022 OldDecl = *MatchedDecl; 3023 3024 // NewFD and OldDecl represent declarations that need to be 3025 // merged. 3026 if (MergeFunctionDecl(NewFD, OldDecl)) 3027 return NewFD->setInvalidDecl(); 3028 3029 if (FunctionTemplateDecl *OldTemplateDecl 3030 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3031 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3032 FunctionTemplateDecl *NewTemplateDecl 3033 = NewFD->getDescribedFunctionTemplate(); 3034 assert(NewTemplateDecl && "Template/non-template mismatch"); 3035 if (CXXMethodDecl *Method 3036 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3037 Method->setAccess(OldTemplateDecl->getAccess()); 3038 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3039 } 3040 3041 // If this is an explicit specialization of a member that is a function 3042 // template, mark it as a member specialization. 3043 if (IsExplicitSpecialization && 3044 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3045 NewTemplateDecl->setMemberSpecialization(); 3046 assert(OldTemplateDecl->isMemberSpecialization()); 3047 } 3048 } else { 3049 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3050 NewFD->setAccess(OldDecl->getAccess()); 3051 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3052 } 3053 } 3054 } 3055 3056 // Semantic checking for this function declaration (in isolation). 3057 if (getLangOptions().CPlusPlus) { 3058 // C++-specific checks. 3059 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3060 CheckConstructor(Constructor); 3061 } else if (isa<CXXDestructorDecl>(NewFD)) { 3062 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3063 QualType ClassType = Context.getTypeDeclType(Record); 3064 if (!ClassType->isDependentType()) { 3065 DeclarationName Name 3066 = Context.DeclarationNames.getCXXDestructorName( 3067 Context.getCanonicalType(ClassType)); 3068 if (NewFD->getDeclName() != Name) { 3069 Diag(NewFD->getLocation(), diag::err_destructor_name); 3070 return NewFD->setInvalidDecl(); 3071 } 3072 } 3073 Record->setUserDeclaredDestructor(true); 3074 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3075 // user-defined destructor. 3076 Record->setPOD(false); 3077 3078 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3079 // declared destructor. 3080 // FIXME: C++0x: don't do this for "= default" destructors 3081 Record->setHasTrivialDestructor(false); 3082 } else if (CXXConversionDecl *Conversion 3083 = dyn_cast<CXXConversionDecl>(NewFD)) 3084 ActOnConversionDeclarator(Conversion); 3085 3086 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3087 if (NewFD->isOverloadedOperator() && 3088 CheckOverloadedOperatorDeclaration(NewFD)) 3089 return NewFD->setInvalidDecl(); 3090 3091 // In C++, check default arguments now that we have merged decls. Unless 3092 // the lexical context is the class, because in this case this is done 3093 // during delayed parsing anyway. 3094 if (!CurContext->isRecord()) 3095 CheckCXXDefaultArguments(NewFD); 3096 } 3097} 3098 3099void Sema::CheckMain(FunctionDecl* FD) { 3100 // C++ [basic.start.main]p3: A program that declares main to be inline 3101 // or static is ill-formed. 3102 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3103 // shall not appear in a declaration of main. 3104 // static main is not an error under C99, but we should warn about it. 3105 bool isInline = FD->isInlineSpecified(); 3106 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3107 if (isInline || isStatic) { 3108 unsigned diagID = diag::warn_unusual_main_decl; 3109 if (isInline || getLangOptions().CPlusPlus) 3110 diagID = diag::err_unusual_main_decl; 3111 3112 int which = isStatic + (isInline << 1) - 1; 3113 Diag(FD->getLocation(), diagID) << which; 3114 } 3115 3116 QualType T = FD->getType(); 3117 assert(T->isFunctionType() && "function decl is not of function type"); 3118 const FunctionType* FT = T->getAs<FunctionType>(); 3119 3120 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3121 // TODO: add a replacement fixit to turn the return type into 'int'. 3122 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3123 FD->setInvalidDecl(true); 3124 } 3125 3126 // Treat protoless main() as nullary. 3127 if (isa<FunctionNoProtoType>(FT)) return; 3128 3129 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3130 unsigned nparams = FTP->getNumArgs(); 3131 assert(FD->getNumParams() == nparams); 3132 3133 if (nparams > 3) { 3134 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3135 FD->setInvalidDecl(true); 3136 nparams = 3; 3137 } 3138 3139 // FIXME: a lot of the following diagnostics would be improved 3140 // if we had some location information about types. 3141 3142 QualType CharPP = 3143 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3144 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3145 3146 for (unsigned i = 0; i < nparams; ++i) { 3147 QualType AT = FTP->getArgType(i); 3148 3149 bool mismatch = true; 3150 3151 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3152 mismatch = false; 3153 else if (Expected[i] == CharPP) { 3154 // As an extension, the following forms are okay: 3155 // char const ** 3156 // char const * const * 3157 // char * const * 3158 3159 QualifierCollector qs; 3160 const PointerType* PT; 3161 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3162 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3163 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3164 qs.removeConst(); 3165 mismatch = !qs.empty(); 3166 } 3167 } 3168 3169 if (mismatch) { 3170 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3171 // TODO: suggest replacing given type with expected type 3172 FD->setInvalidDecl(true); 3173 } 3174 } 3175 3176 if (nparams == 1 && !FD->isInvalidDecl()) { 3177 Diag(FD->getLocation(), diag::warn_main_one_arg); 3178 } 3179} 3180 3181bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3182 // FIXME: Need strict checking. In C89, we need to check for 3183 // any assignment, increment, decrement, function-calls, or 3184 // commas outside of a sizeof. In C99, it's the same list, 3185 // except that the aforementioned are allowed in unevaluated 3186 // expressions. Everything else falls under the 3187 // "may accept other forms of constant expressions" exception. 3188 // (We never end up here for C++, so the constant expression 3189 // rules there don't matter.) 3190 if (Init->isConstantInitializer(Context)) 3191 return false; 3192 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3193 << Init->getSourceRange(); 3194 return true; 3195} 3196 3197void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3198 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3199} 3200 3201/// AddInitializerToDecl - Adds the initializer Init to the 3202/// declaration dcl. If DirectInit is true, this is C++ direct 3203/// initialization rather than copy initialization. 3204void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3205 Decl *RealDecl = dcl.getAs<Decl>(); 3206 // If there is no declaration, there was an error parsing it. Just ignore 3207 // the initializer. 3208 if (RealDecl == 0) 3209 return; 3210 3211 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3212 // With declarators parsed the way they are, the parser cannot 3213 // distinguish between a normal initializer and a pure-specifier. 3214 // Thus this grotesque test. 3215 IntegerLiteral *IL; 3216 Expr *Init = static_cast<Expr *>(init.get()); 3217 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3218 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3219 if (Method->isVirtualAsWritten()) { 3220 Method->setPure(); 3221 3222 // A class is abstract if at least one function is pure virtual. 3223 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3224 } else if (!Method->isInvalidDecl()) { 3225 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3226 << Method->getDeclName() << Init->getSourceRange(); 3227 Method->setInvalidDecl(); 3228 } 3229 } else { 3230 Diag(Method->getLocation(), diag::err_member_function_initialization) 3231 << Method->getDeclName() << Init->getSourceRange(); 3232 Method->setInvalidDecl(); 3233 } 3234 return; 3235 } 3236 3237 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3238 if (!VDecl) { 3239 if (getLangOptions().CPlusPlus && 3240 RealDecl->getLexicalDeclContext()->isRecord() && 3241 isa<NamedDecl>(RealDecl)) 3242 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3243 << cast<NamedDecl>(RealDecl)->getDeclName(); 3244 else 3245 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3246 RealDecl->setInvalidDecl(); 3247 return; 3248 } 3249 3250 if (!VDecl->getType()->isArrayType() && 3251 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3252 diag::err_typecheck_decl_incomplete_type)) { 3253 RealDecl->setInvalidDecl(); 3254 return; 3255 } 3256 3257 const VarDecl *Def = 0; 3258 if (VDecl->getDefinition(Def)) { 3259 Diag(VDecl->getLocation(), diag::err_redefinition) 3260 << VDecl->getDeclName(); 3261 Diag(Def->getLocation(), diag::note_previous_definition); 3262 VDecl->setInvalidDecl(); 3263 return; 3264 } 3265 3266 // Take ownership of the expression, now that we're sure we have somewhere 3267 // to put it. 3268 Expr *Init = init.takeAs<Expr>(); 3269 assert(Init && "missing initializer"); 3270 3271 // Get the decls type and save a reference for later, since 3272 // CheckInitializerTypes may change it. 3273 QualType DclT = VDecl->getType(), SavT = DclT; 3274 if (VDecl->isBlockVarDecl()) { 3275 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3276 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3277 VDecl->setInvalidDecl(); 3278 } else if (!VDecl->isInvalidDecl()) { 3279 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3280 VDecl->getDeclName(), DirectInit)) 3281 VDecl->setInvalidDecl(); 3282 3283 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3284 // Don't check invalid declarations to avoid emitting useless diagnostics. 3285 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3286 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3287 CheckForConstantInitializer(Init, DclT); 3288 } 3289 } 3290 } else if (VDecl->isStaticDataMember() && 3291 VDecl->getLexicalDeclContext()->isRecord()) { 3292 // This is an in-class initialization for a static data member, e.g., 3293 // 3294 // struct S { 3295 // static const int value = 17; 3296 // }; 3297 3298 // Attach the initializer 3299 VDecl->setInit(Context, Init); 3300 3301 // C++ [class.mem]p4: 3302 // A member-declarator can contain a constant-initializer only 3303 // if it declares a static member (9.4) of const integral or 3304 // const enumeration type, see 9.4.2. 3305 QualType T = VDecl->getType(); 3306 if (!T->isDependentType() && 3307 (!Context.getCanonicalType(T).isConstQualified() || 3308 !T->isIntegralType())) { 3309 Diag(VDecl->getLocation(), diag::err_member_initialization) 3310 << VDecl->getDeclName() << Init->getSourceRange(); 3311 VDecl->setInvalidDecl(); 3312 } else { 3313 // C++ [class.static.data]p4: 3314 // If a static data member is of const integral or const 3315 // enumeration type, its declaration in the class definition 3316 // can specify a constant-initializer which shall be an 3317 // integral constant expression (5.19). 3318 if (!Init->isTypeDependent() && 3319 !Init->getType()->isIntegralType()) { 3320 // We have a non-dependent, non-integral or enumeration type. 3321 Diag(Init->getSourceRange().getBegin(), 3322 diag::err_in_class_initializer_non_integral_type) 3323 << Init->getType() << Init->getSourceRange(); 3324 VDecl->setInvalidDecl(); 3325 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3326 // Check whether the expression is a constant expression. 3327 llvm::APSInt Value; 3328 SourceLocation Loc; 3329 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3330 Diag(Loc, diag::err_in_class_initializer_non_constant) 3331 << Init->getSourceRange(); 3332 VDecl->setInvalidDecl(); 3333 } else if (!VDecl->getType()->isDependentType()) 3334 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3335 } 3336 } 3337 } else if (VDecl->isFileVarDecl()) { 3338 if (VDecl->getStorageClass() == VarDecl::Extern) 3339 Diag(VDecl->getLocation(), diag::warn_extern_init); 3340 if (!VDecl->isInvalidDecl()) 3341 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3342 VDecl->getDeclName(), DirectInit)) 3343 VDecl->setInvalidDecl(); 3344 3345 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3346 // Don't check invalid declarations to avoid emitting useless diagnostics. 3347 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3348 // C99 6.7.8p4. All file scoped initializers need to be constant. 3349 CheckForConstantInitializer(Init, DclT); 3350 } 3351 } 3352 // If the type changed, it means we had an incomplete type that was 3353 // completed by the initializer. For example: 3354 // int ary[] = { 1, 3, 5 }; 3355 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3356 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3357 VDecl->setType(DclT); 3358 Init->setType(DclT); 3359 } 3360 3361 Init = MaybeCreateCXXExprWithTemporaries(Init, 3362 /*ShouldDestroyTemporaries=*/true); 3363 // Attach the initializer to the decl. 3364 VDecl->setInit(Context, Init); 3365 3366 // If the previous declaration of VDecl was a tentative definition, 3367 // remove it from the set of tentative definitions. 3368 if (VDecl->getPreviousDeclaration() && 3369 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3370 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3371 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3372 } 3373 3374 return; 3375} 3376 3377void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3378 bool TypeContainsUndeducedAuto) { 3379 Decl *RealDecl = dcl.getAs<Decl>(); 3380 3381 // If there is no declaration, there was an error parsing it. Just ignore it. 3382 if (RealDecl == 0) 3383 return; 3384 3385 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3386 QualType Type = Var->getType(); 3387 3388 // Record tentative definitions. 3389 if (Var->isTentativeDefinition(Context)) { 3390 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3391 InsertPair = 3392 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3393 3394 // Keep the latest definition in the map. If we see 'int i; int i;' we 3395 // want the second one in the map. 3396 InsertPair.first->second = Var; 3397 3398 // However, for the list, we don't care about the order, just make sure 3399 // that there are no dupes for a given declaration name. 3400 if (InsertPair.second) 3401 TentativeDefinitionList.push_back(Var->getDeclName()); 3402 } 3403 3404 // C++ [dcl.init.ref]p3: 3405 // The initializer can be omitted for a reference only in a 3406 // parameter declaration (8.3.5), in the declaration of a 3407 // function return type, in the declaration of a class member 3408 // within its class declaration (9.2), and where the extern 3409 // specifier is explicitly used. 3410 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3411 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3412 << Var->getDeclName() 3413 << SourceRange(Var->getLocation(), Var->getLocation()); 3414 Var->setInvalidDecl(); 3415 return; 3416 } 3417 3418 // C++0x [dcl.spec.auto]p3 3419 if (TypeContainsUndeducedAuto) { 3420 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3421 << Var->getDeclName() << Type; 3422 Var->setInvalidDecl(); 3423 return; 3424 } 3425 3426 // C++ [temp.expl.spec]p15: 3427 // An explicit specialization of a static data member of a template is a 3428 // definition if the declaration includes an initializer; otherwise, it 3429 // is a declaration. 3430 if (Var->isStaticDataMember() && 3431 Var->getInstantiatedFromStaticDataMember() && 3432 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3433 return; 3434 3435 // C++ [dcl.init]p9: 3436 // If no initializer is specified for an object, and the object 3437 // is of (possibly cv-qualified) non-POD class type (or array 3438 // thereof), the object shall be default-initialized; if the 3439 // object is of const-qualified type, the underlying class type 3440 // shall have a user-declared default constructor. 3441 // 3442 // FIXME: Diagnose the "user-declared default constructor" bit. 3443 if (getLangOptions().CPlusPlus) { 3444 QualType InitType = Type; 3445 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3446 InitType = Array->getElementType(); 3447 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3448 InitType->isRecordType() && !InitType->isDependentType()) { 3449 if (!RequireCompleteType(Var->getLocation(), InitType, 3450 diag::err_invalid_incomplete_type_use)) { 3451 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3452 3453 CXXConstructorDecl *Constructor 3454 = PerformInitializationByConstructor(InitType, 3455 MultiExprArg(*this, 0, 0), 3456 Var->getLocation(), 3457 SourceRange(Var->getLocation(), 3458 Var->getLocation()), 3459 Var->getDeclName(), 3460 IK_Default, 3461 ConstructorArgs); 3462 3463 // FIXME: Location info for the variable initialization? 3464 if (!Constructor) 3465 Var->setInvalidDecl(); 3466 else { 3467 // FIXME: Cope with initialization of arrays 3468 if (!Constructor->isTrivial() && 3469 InitializeVarWithConstructor(Var, Constructor, InitType, 3470 move_arg(ConstructorArgs))) 3471 Var->setInvalidDecl(); 3472 3473 FinalizeVarWithDestructor(Var, InitType); 3474 } 3475 } else { 3476 Var->setInvalidDecl(); 3477 } 3478 } 3479 } 3480 3481#if 0 3482 // FIXME: Temporarily disabled because we are not properly parsing 3483 // linkage specifications on declarations, e.g., 3484 // 3485 // extern "C" const CGPoint CGPointerZero; 3486 // 3487 // C++ [dcl.init]p9: 3488 // 3489 // If no initializer is specified for an object, and the 3490 // object is of (possibly cv-qualified) non-POD class type (or 3491 // array thereof), the object shall be default-initialized; if 3492 // the object is of const-qualified type, the underlying class 3493 // type shall have a user-declared default 3494 // constructor. Otherwise, if no initializer is specified for 3495 // an object, the object and its subobjects, if any, have an 3496 // indeterminate initial value; if the object or any of its 3497 // subobjects are of const-qualified type, the program is 3498 // ill-formed. 3499 // 3500 // This isn't technically an error in C, so we don't diagnose it. 3501 // 3502 // FIXME: Actually perform the POD/user-defined default 3503 // constructor check. 3504 if (getLangOptions().CPlusPlus && 3505 Context.getCanonicalType(Type).isConstQualified() && 3506 !Var->hasExternalStorage()) 3507 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3508 << Var->getName() 3509 << SourceRange(Var->getLocation(), Var->getLocation()); 3510#endif 3511 } 3512} 3513 3514Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3515 DeclPtrTy *Group, 3516 unsigned NumDecls) { 3517 llvm::SmallVector<Decl*, 8> Decls; 3518 3519 if (DS.isTypeSpecOwned()) 3520 Decls.push_back((Decl*)DS.getTypeRep()); 3521 3522 for (unsigned i = 0; i != NumDecls; ++i) 3523 if (Decl *D = Group[i].getAs<Decl>()) 3524 Decls.push_back(D); 3525 3526 // Perform semantic analysis that depends on having fully processed both 3527 // the declarator and initializer. 3528 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3529 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3530 if (!IDecl) 3531 continue; 3532 QualType T = IDecl->getType(); 3533 3534 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3535 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3536 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3537 if (T->isDependentType()) { 3538 // If T is dependent, we should not require a complete type. 3539 // (RequireCompleteType shouldn't be called with dependent types.) 3540 // But we still can at least check if we've got an array of unspecified 3541 // size without an initializer. 3542 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3543 !IDecl->getInit()) { 3544 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3545 << T; 3546 IDecl->setInvalidDecl(); 3547 } 3548 } else if (!IDecl->isInvalidDecl()) { 3549 // If T is an incomplete array type with an initializer list that is 3550 // dependent on something, its size has not been fixed. We could attempt 3551 // to fix the size for such arrays, but we would still have to check 3552 // here for initializers containing a C++0x vararg expansion, e.g. 3553 // template <typename... Args> void f(Args... args) { 3554 // int vals[] = { args }; 3555 // } 3556 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3557 Expr *Init = IDecl->getInit(); 3558 if (IAT && Init && 3559 (Init->isTypeDependent() || Init->isValueDependent())) { 3560 // Check that the member type of the array is complete, at least. 3561 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3562 diag::err_typecheck_decl_incomplete_type)) 3563 IDecl->setInvalidDecl(); 3564 } else if (RequireCompleteType(IDecl->getLocation(), T, 3565 diag::err_typecheck_decl_incomplete_type)) 3566 IDecl->setInvalidDecl(); 3567 } 3568 } 3569 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3570 // object that has file scope without an initializer, and without a 3571 // storage-class specifier or with the storage-class specifier "static", 3572 // constitutes a tentative definition. Note: A tentative definition with 3573 // external linkage is valid (C99 6.2.2p5). 3574 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3575 if (const IncompleteArrayType *ArrayT 3576 = Context.getAsIncompleteArrayType(T)) { 3577 if (RequireCompleteType(IDecl->getLocation(), 3578 ArrayT->getElementType(), 3579 diag::err_illegal_decl_array_incomplete_type)) 3580 IDecl->setInvalidDecl(); 3581 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3582 // C99 6.9.2p3: If the declaration of an identifier for an object is 3583 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3584 // declared type shall not be an incomplete type. 3585 // NOTE: code such as the following 3586 // static struct s; 3587 // struct s { int a; }; 3588 // is accepted by gcc. Hence here we issue a warning instead of 3589 // an error and we do not invalidate the static declaration. 3590 // NOTE: to avoid multiple warnings, only check the first declaration. 3591 if (IDecl->getPreviousDeclaration() == 0) 3592 RequireCompleteType(IDecl->getLocation(), T, 3593 diag::ext_typecheck_decl_incomplete_type); 3594 } 3595 } 3596 } 3597 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3598 Decls.data(), Decls.size())); 3599} 3600 3601 3602/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3603/// to introduce parameters into function prototype scope. 3604Sema::DeclPtrTy 3605Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3606 const DeclSpec &DS = D.getDeclSpec(); 3607 3608 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3609 VarDecl::StorageClass StorageClass = VarDecl::None; 3610 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3611 StorageClass = VarDecl::Register; 3612 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3613 Diag(DS.getStorageClassSpecLoc(), 3614 diag::err_invalid_storage_class_in_func_decl); 3615 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3616 } 3617 3618 if (D.getDeclSpec().isThreadSpecified()) 3619 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3620 3621 DiagnoseFunctionSpecifiers(D); 3622 3623 // Check that there are no default arguments inside the type of this 3624 // parameter (C++ only). 3625 if (getLangOptions().CPlusPlus) 3626 CheckExtraCXXDefaultArguments(D); 3627 3628 DeclaratorInfo *DInfo = 0; 3629 TagDecl *OwnedDecl = 0; 3630 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3631 3632 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3633 // C++ [dcl.fct]p6: 3634 // Types shall not be defined in return or parameter types. 3635 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3636 << Context.getTypeDeclType(OwnedDecl); 3637 } 3638 3639 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3640 // Can this happen for params? We already checked that they don't conflict 3641 // among each other. Here they can only shadow globals, which is ok. 3642 IdentifierInfo *II = D.getIdentifier(); 3643 if (II) { 3644 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3645 if (PrevDecl->isTemplateParameter()) { 3646 // Maybe we will complain about the shadowed template parameter. 3647 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3648 // Just pretend that we didn't see the previous declaration. 3649 PrevDecl = 0; 3650 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3651 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3652 3653 // Recover by removing the name 3654 II = 0; 3655 D.SetIdentifier(0, D.getIdentifierLoc()); 3656 } 3657 } 3658 } 3659 3660 // Parameters can not be abstract class types. 3661 // For record types, this is done by the AbstractClassUsageDiagnoser once 3662 // the class has been completely parsed. 3663 if (!CurContext->isRecord() && 3664 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3665 diag::err_abstract_type_in_decl, 3666 AbstractParamType)) 3667 D.setInvalidType(true); 3668 3669 QualType T = adjustParameterType(parmDeclType); 3670 3671 ParmVarDecl *New 3672 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3673 T, DInfo, StorageClass, 0); 3674 3675 if (D.isInvalidType()) 3676 New->setInvalidDecl(); 3677 3678 // Parameter declarators cannot be interface types. All ObjC objects are 3679 // passed by reference. 3680 if (T->isObjCInterfaceType()) { 3681 Diag(D.getIdentifierLoc(), 3682 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3683 New->setInvalidDecl(); 3684 } 3685 3686 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3687 if (D.getCXXScopeSpec().isSet()) { 3688 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3689 << D.getCXXScopeSpec().getRange(); 3690 New->setInvalidDecl(); 3691 } 3692 3693 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3694 // duration shall not be qualified by an address-space qualifier." 3695 // Since all parameters have automatic store duration, they can not have 3696 // an address space. 3697 if (T.getAddressSpace() != 0) { 3698 Diag(D.getIdentifierLoc(), 3699 diag::err_arg_with_address_space); 3700 New->setInvalidDecl(); 3701 } 3702 3703 3704 // Add the parameter declaration into this scope. 3705 S->AddDecl(DeclPtrTy::make(New)); 3706 if (II) 3707 IdResolver.AddDecl(New); 3708 3709 ProcessDeclAttributes(S, New, D); 3710 3711 if (New->hasAttr<BlocksAttr>()) { 3712 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3713 } 3714 return DeclPtrTy::make(New); 3715} 3716 3717void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3718 SourceLocation LocAfterDecls) { 3719 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3720 "Not a function declarator!"); 3721 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3722 3723 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3724 // for a K&R function. 3725 if (!FTI.hasPrototype) { 3726 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3727 --i; 3728 if (FTI.ArgInfo[i].Param == 0) { 3729 llvm::SmallString<256> Code; 3730 llvm::raw_svector_ostream(Code) << " int " 3731 << FTI.ArgInfo[i].Ident->getName() 3732 << ";\n"; 3733 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3734 << FTI.ArgInfo[i].Ident 3735 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3736 3737 // Implicitly declare the argument as type 'int' for lack of a better 3738 // type. 3739 DeclSpec DS; 3740 const char* PrevSpec; // unused 3741 unsigned DiagID; // unused 3742 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3743 PrevSpec, DiagID); 3744 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3745 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3746 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3747 } 3748 } 3749 } 3750} 3751 3752Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3753 Declarator &D) { 3754 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3755 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3756 "Not a function declarator!"); 3757 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3758 3759 if (FTI.hasPrototype) { 3760 // FIXME: Diagnose arguments without names in C. 3761 } 3762 3763 Scope *ParentScope = FnBodyScope->getParent(); 3764 3765 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3766 MultiTemplateParamsArg(*this), 3767 /*IsFunctionDefinition=*/true); 3768 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3769} 3770 3771Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3772 if (!D) 3773 return D; 3774 FunctionDecl *FD = 0; 3775 3776 if (FunctionTemplateDecl *FunTmpl 3777 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3778 FD = FunTmpl->getTemplatedDecl(); 3779 else 3780 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3781 3782 CurFunctionNeedsScopeChecking = false; 3783 3784 // See if this is a redefinition. 3785 const FunctionDecl *Definition; 3786 if (FD->getBody(Definition)) { 3787 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3788 Diag(Definition->getLocation(), diag::note_previous_definition); 3789 } 3790 3791 // Builtin functions cannot be defined. 3792 if (unsigned BuiltinID = FD->getBuiltinID()) { 3793 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3794 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3795 FD->setInvalidDecl(); 3796 } 3797 } 3798 3799 // The return type of a function definition must be complete 3800 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3801 QualType ResultType = FD->getResultType(); 3802 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3803 !FD->isInvalidDecl() && 3804 RequireCompleteType(FD->getLocation(), ResultType, 3805 diag::err_func_def_incomplete_result)) 3806 FD->setInvalidDecl(); 3807 3808 // GNU warning -Wmissing-prototypes: 3809 // Warn if a global function is defined without a previous 3810 // prototype declaration. This warning is issued even if the 3811 // definition itself provides a prototype. The aim is to detect 3812 // global functions that fail to be declared in header files. 3813 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3814 !FD->isMain()) { 3815 bool MissingPrototype = true; 3816 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3817 Prev; Prev = Prev->getPreviousDeclaration()) { 3818 // Ignore any declarations that occur in function or method 3819 // scope, because they aren't visible from the header. 3820 if (Prev->getDeclContext()->isFunctionOrMethod()) 3821 continue; 3822 3823 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3824 break; 3825 } 3826 3827 if (MissingPrototype) 3828 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3829 } 3830 3831 if (FnBodyScope) 3832 PushDeclContext(FnBodyScope, FD); 3833 3834 // Check the validity of our function parameters 3835 CheckParmsForFunctionDef(FD); 3836 3837 // Introduce our parameters into the function scope 3838 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3839 ParmVarDecl *Param = FD->getParamDecl(p); 3840 Param->setOwningFunction(FD); 3841 3842 // If this has an identifier, add it to the scope stack. 3843 if (Param->getIdentifier() && FnBodyScope) 3844 PushOnScopeChains(Param, FnBodyScope); 3845 } 3846 3847 // Checking attributes of current function definition 3848 // dllimport attribute. 3849 if (FD->getAttr<DLLImportAttr>() && 3850 (!FD->getAttr<DLLExportAttr>())) { 3851 // dllimport attribute cannot be applied to definition. 3852 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3853 Diag(FD->getLocation(), 3854 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3855 << "dllimport"; 3856 FD->setInvalidDecl(); 3857 return DeclPtrTy::make(FD); 3858 } else { 3859 // If a symbol previously declared dllimport is later defined, the 3860 // attribute is ignored in subsequent references, and a warning is 3861 // emitted. 3862 Diag(FD->getLocation(), 3863 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3864 << FD->getNameAsCString() << "dllimport"; 3865 } 3866 } 3867 return DeclPtrTy::make(FD); 3868} 3869 3870Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3871 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3872} 3873 3874Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3875 bool IsInstantiation) { 3876 Decl *dcl = D.getAs<Decl>(); 3877 Stmt *Body = BodyArg.takeAs<Stmt>(); 3878 3879 FunctionDecl *FD = 0; 3880 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3881 if (FunTmpl) 3882 FD = FunTmpl->getTemplatedDecl(); 3883 else 3884 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3885 3886 if (FD) { 3887 FD->setBody(Body); 3888 if (FD->isMain()) 3889 // C and C++ allow for main to automagically return 0. 3890 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3891 FD->setHasImplicitReturnZero(true); 3892 else 3893 CheckFallThroughForFunctionDef(FD, Body); 3894 3895 if (!FD->isInvalidDecl()) 3896 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3897 3898 // C++ [basic.def.odr]p2: 3899 // [...] A virtual member function is used if it is not pure. [...] 3900 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3901 if (Method->isVirtual() && !Method->isPure()) 3902 MarkDeclarationReferenced(Method->getLocation(), Method); 3903 3904 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3905 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3906 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3907 MD->setBody(Body); 3908 CheckFallThroughForFunctionDef(MD, Body); 3909 MD->setEndLoc(Body->getLocEnd()); 3910 3911 if (!MD->isInvalidDecl()) 3912 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3913 } else { 3914 Body->Destroy(Context); 3915 return DeclPtrTy(); 3916 } 3917 if (!IsInstantiation) 3918 PopDeclContext(); 3919 3920 // Verify and clean out per-function state. 3921 3922 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3923 3924 // Check goto/label use. 3925 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3926 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3927 LabelStmt *L = I->second; 3928 3929 // Verify that we have no forward references left. If so, there was a goto 3930 // or address of a label taken, but no definition of it. Label fwd 3931 // definitions are indicated with a null substmt. 3932 if (L->getSubStmt() != 0) 3933 continue; 3934 3935 // Emit error. 3936 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3937 3938 // At this point, we have gotos that use the bogus label. Stitch it into 3939 // the function body so that they aren't leaked and that the AST is well 3940 // formed. 3941 if (Body == 0) { 3942 // The whole function wasn't parsed correctly, just delete this. 3943 L->Destroy(Context); 3944 continue; 3945 } 3946 3947 // Otherwise, the body is valid: we want to stitch the label decl into the 3948 // function somewhere so that it is properly owned and so that the goto 3949 // has a valid target. Do this by creating a new compound stmt with the 3950 // label in it. 3951 3952 // Give the label a sub-statement. 3953 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3954 3955 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3956 cast<CXXTryStmt>(Body)->getTryBlock() : 3957 cast<CompoundStmt>(Body); 3958 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3959 Elements.push_back(L); 3960 Compound->setStmts(Context, &Elements[0], Elements.size()); 3961 } 3962 FunctionLabelMap.clear(); 3963 3964 if (!Body) return D; 3965 3966 // Verify that that gotos and switch cases don't jump into scopes illegally. 3967 if (CurFunctionNeedsScopeChecking) 3968 DiagnoseInvalidJumps(Body); 3969 3970 // C++ constructors that have function-try-blocks can't have return 3971 // statements in the handlers of that block. (C++ [except.handle]p14) 3972 // Verify this. 3973 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3974 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3975 3976 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3977 computeBaseOrMembersToDestroy(Destructor); 3978 return D; 3979} 3980 3981/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3982/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3983NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3984 IdentifierInfo &II, Scope *S) { 3985 // Before we produce a declaration for an implicitly defined 3986 // function, see whether there was a locally-scoped declaration of 3987 // this name as a function or variable. If so, use that 3988 // (non-visible) declaration, and complain about it. 3989 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3990 = LocallyScopedExternalDecls.find(&II); 3991 if (Pos != LocallyScopedExternalDecls.end()) { 3992 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3993 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3994 return Pos->second; 3995 } 3996 3997 // Extension in C99. Legal in C90, but warn about it. 3998 if (II.getName().startswith("__builtin_")) 3999 Diag(Loc, diag::warn_builtin_unknown) << &II; 4000 else if (getLangOptions().C99) 4001 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4002 else 4003 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4004 4005 // Set a Declarator for the implicit definition: int foo(); 4006 const char *Dummy; 4007 DeclSpec DS; 4008 unsigned DiagID; 4009 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4010 Error = Error; // Silence warning. 4011 assert(!Error && "Error setting up implicit decl!"); 4012 Declarator D(DS, Declarator::BlockContext); 4013 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4014 0, 0, false, SourceLocation(), 4015 false, 0,0,0, Loc, Loc, D), 4016 SourceLocation()); 4017 D.SetIdentifier(&II, Loc); 4018 4019 // Insert this function into translation-unit scope. 4020 4021 DeclContext *PrevDC = CurContext; 4022 CurContext = Context.getTranslationUnitDecl(); 4023 4024 FunctionDecl *FD = 4025 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4026 FD->setImplicit(); 4027 4028 CurContext = PrevDC; 4029 4030 AddKnownFunctionAttributes(FD); 4031 4032 return FD; 4033} 4034 4035/// \brief Adds any function attributes that we know a priori based on 4036/// the declaration of this function. 4037/// 4038/// These attributes can apply both to implicitly-declared builtins 4039/// (like __builtin___printf_chk) or to library-declared functions 4040/// like NSLog or printf. 4041void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4042 if (FD->isInvalidDecl()) 4043 return; 4044 4045 // If this is a built-in function, map its builtin attributes to 4046 // actual attributes. 4047 if (unsigned BuiltinID = FD->getBuiltinID()) { 4048 // Handle printf-formatting attributes. 4049 unsigned FormatIdx; 4050 bool HasVAListArg; 4051 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4052 if (!FD->getAttr<FormatAttr>()) 4053 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4054 HasVAListArg ? 0 : FormatIdx + 2)); 4055 } 4056 4057 // Mark const if we don't care about errno and that is the only 4058 // thing preventing the function from being const. This allows 4059 // IRgen to use LLVM intrinsics for such functions. 4060 if (!getLangOptions().MathErrno && 4061 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4062 if (!FD->getAttr<ConstAttr>()) 4063 FD->addAttr(::new (Context) ConstAttr()); 4064 } 4065 4066 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4067 FD->addAttr(::new (Context) NoReturnAttr()); 4068 } 4069 4070 IdentifierInfo *Name = FD->getIdentifier(); 4071 if (!Name) 4072 return; 4073 if ((!getLangOptions().CPlusPlus && 4074 FD->getDeclContext()->isTranslationUnit()) || 4075 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4076 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4077 LinkageSpecDecl::lang_c)) { 4078 // Okay: this could be a libc/libm/Objective-C function we know 4079 // about. 4080 } else 4081 return; 4082 4083 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4084 // FIXME: NSLog and NSLogv should be target specific 4085 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4086 // FIXME: We known better than our headers. 4087 const_cast<FormatAttr *>(Format)->setType("printf"); 4088 } else 4089 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4090 Name->isStr("NSLogv") ? 0 : 2)); 4091 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4092 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4093 // target-specific builtins, perhaps? 4094 if (!FD->getAttr<FormatAttr>()) 4095 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4096 Name->isStr("vasprintf") ? 0 : 3)); 4097 } 4098} 4099 4100TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4101 DeclaratorInfo *DInfo) { 4102 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4103 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4104 4105 if (!DInfo) { 4106 assert(D.isInvalidType() && "no declarator info for valid type"); 4107 DInfo = Context.getTrivialDeclaratorInfo(T); 4108 } 4109 4110 // Scope manipulation handled by caller. 4111 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4112 D.getIdentifierLoc(), 4113 D.getIdentifier(), 4114 DInfo); 4115 4116 if (const TagType *TT = T->getAs<TagType>()) { 4117 TagDecl *TD = TT->getDecl(); 4118 4119 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4120 // keep track of the TypedefDecl. 4121 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4122 TD->setTypedefForAnonDecl(NewTD); 4123 } 4124 4125 if (D.isInvalidType()) 4126 NewTD->setInvalidDecl(); 4127 return NewTD; 4128} 4129 4130 4131/// \brief Determine whether a tag with a given kind is acceptable 4132/// as a redeclaration of the given tag declaration. 4133/// 4134/// \returns true if the new tag kind is acceptable, false otherwise. 4135bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4136 TagDecl::TagKind NewTag, 4137 SourceLocation NewTagLoc, 4138 const IdentifierInfo &Name) { 4139 // C++ [dcl.type.elab]p3: 4140 // The class-key or enum keyword present in the 4141 // elaborated-type-specifier shall agree in kind with the 4142 // declaration to which the name in theelaborated-type-specifier 4143 // refers. This rule also applies to the form of 4144 // elaborated-type-specifier that declares a class-name or 4145 // friend class since it can be construed as referring to the 4146 // definition of the class. Thus, in any 4147 // elaborated-type-specifier, the enum keyword shall be used to 4148 // refer to an enumeration (7.2), the union class-keyshall be 4149 // used to refer to a union (clause 9), and either the class or 4150 // struct class-key shall be used to refer to a class (clause 9) 4151 // declared using the class or struct class-key. 4152 TagDecl::TagKind OldTag = Previous->getTagKind(); 4153 if (OldTag == NewTag) 4154 return true; 4155 4156 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4157 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4158 // Warn about the struct/class tag mismatch. 4159 bool isTemplate = false; 4160 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4161 isTemplate = Record->getDescribedClassTemplate(); 4162 4163 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4164 << (NewTag == TagDecl::TK_class) 4165 << isTemplate << &Name 4166 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4167 OldTag == TagDecl::TK_class? "class" : "struct"); 4168 Diag(Previous->getLocation(), diag::note_previous_use); 4169 return true; 4170 } 4171 return false; 4172} 4173 4174/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4175/// former case, Name will be non-null. In the later case, Name will be null. 4176/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4177/// reference/declaration/definition of a tag. 4178Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4179 SourceLocation KWLoc, const CXXScopeSpec &SS, 4180 IdentifierInfo *Name, SourceLocation NameLoc, 4181 AttributeList *Attr, AccessSpecifier AS, 4182 MultiTemplateParamsArg TemplateParameterLists, 4183 bool &OwnedDecl, bool &IsDependent) { 4184 // If this is not a definition, it must have a name. 4185 assert((Name != 0 || TUK == TUK_Definition) && 4186 "Nameless record must be a definition!"); 4187 4188 OwnedDecl = false; 4189 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4190 4191 // FIXME: Check explicit specializations more carefully. 4192 bool isExplicitSpecialization = false; 4193 if (TUK != TUK_Reference) { 4194 if (TemplateParameterList *TemplateParams 4195 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4196 (TemplateParameterList**)TemplateParameterLists.get(), 4197 TemplateParameterLists.size(), 4198 isExplicitSpecialization)) { 4199 if (TemplateParams->size() > 0) { 4200 // This is a declaration or definition of a class template (which may 4201 // be a member of another template). 4202 OwnedDecl = false; 4203 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4204 SS, Name, NameLoc, Attr, 4205 TemplateParams, 4206 AS); 4207 TemplateParameterLists.release(); 4208 return Result.get(); 4209 } else { 4210 // The "template<>" header is extraneous. 4211 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4212 << ElaboratedType::getNameForTagKind(Kind) << Name; 4213 isExplicitSpecialization = true; 4214 } 4215 } 4216 4217 TemplateParameterLists.release(); 4218 } 4219 4220 DeclContext *SearchDC = CurContext; 4221 DeclContext *DC = CurContext; 4222 NamedDecl *PrevDecl = 0; 4223 bool isStdBadAlloc = false; 4224 bool Invalid = false; 4225 4226 bool RedeclarationOnly = (TUK != TUK_Reference); 4227 4228 if (Name && SS.isNotEmpty()) { 4229 // We have a nested-name tag ('struct foo::bar'). 4230 4231 // Check for invalid 'foo::'. 4232 if (SS.isInvalid()) { 4233 Name = 0; 4234 goto CreateNewDecl; 4235 } 4236 4237 // If this is a friend or a reference to a class in a dependent 4238 // context, don't try to make a decl for it. 4239 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4240 DC = computeDeclContext(SS, false); 4241 if (!DC) { 4242 IsDependent = true; 4243 return DeclPtrTy(); 4244 } 4245 } 4246 4247 if (RequireCompleteDeclContext(SS)) 4248 return DeclPtrTy::make((Decl *)0); 4249 4250 DC = computeDeclContext(SS, true); 4251 SearchDC = DC; 4252 // Look-up name inside 'foo::'. 4253 LookupResult R; 4254 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4255 4256 if (R.isAmbiguous()) { 4257 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4258 return DeclPtrTy(); 4259 } 4260 4261 if (R.getKind() == LookupResult::Found) 4262 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4263 4264 // A tag 'foo::bar' must already exist. 4265 if (!PrevDecl) { 4266 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4267 Name = 0; 4268 Invalid = true; 4269 goto CreateNewDecl; 4270 } 4271 } else if (Name) { 4272 // If this is a named struct, check to see if there was a previous forward 4273 // declaration or definition. 4274 // FIXME: We're looking into outer scopes here, even when we 4275 // shouldn't be. Doing so can result in ambiguities that we 4276 // shouldn't be diagnosing. 4277 LookupResult R; 4278 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4279 if (R.isAmbiguous()) { 4280 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4281 // FIXME: This is not best way to recover from case like: 4282 // 4283 // struct S s; 4284 // 4285 // causes needless "incomplete type" error later. 4286 Name = 0; 4287 PrevDecl = 0; 4288 Invalid = true; 4289 } else 4290 PrevDecl = R.getAsSingleDecl(Context); 4291 4292 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4293 // FIXME: This makes sure that we ignore the contexts associated 4294 // with C structs, unions, and enums when looking for a matching 4295 // tag declaration or definition. See the similar lookup tweak 4296 // in Sema::LookupName; is there a better way to deal with this? 4297 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4298 SearchDC = SearchDC->getParent(); 4299 } 4300 } 4301 4302 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4303 // Maybe we will complain about the shadowed template parameter. 4304 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4305 // Just pretend that we didn't see the previous declaration. 4306 PrevDecl = 0; 4307 } 4308 4309 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4310 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4311 // This is a declaration of or a reference to "std::bad_alloc". 4312 isStdBadAlloc = true; 4313 4314 if (!PrevDecl && StdBadAlloc) { 4315 // std::bad_alloc has been implicitly declared (but made invisible to 4316 // name lookup). Fill in this implicit declaration as the previous 4317 // declaration, so that the declarations get chained appropriately. 4318 PrevDecl = StdBadAlloc; 4319 } 4320 } 4321 4322 if (PrevDecl) { 4323 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4324 // If this is a use of a previous tag, or if the tag is already declared 4325 // in the same scope (so that the definition/declaration completes or 4326 // rementions the tag), reuse the decl. 4327 if (TUK == TUK_Reference || TUK == TUK_Friend || 4328 isDeclInScope(PrevDecl, SearchDC, S)) { 4329 // Make sure that this wasn't declared as an enum and now used as a 4330 // struct or something similar. 4331 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4332 bool SafeToContinue 4333 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4334 Kind != TagDecl::TK_enum); 4335 if (SafeToContinue) 4336 Diag(KWLoc, diag::err_use_with_wrong_tag) 4337 << Name 4338 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4339 PrevTagDecl->getKindName()); 4340 else 4341 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4342 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4343 4344 if (SafeToContinue) 4345 Kind = PrevTagDecl->getTagKind(); 4346 else { 4347 // Recover by making this an anonymous redefinition. 4348 Name = 0; 4349 PrevDecl = 0; 4350 Invalid = true; 4351 } 4352 } 4353 4354 if (!Invalid) { 4355 // If this is a use, just return the declaration we found. 4356 4357 // FIXME: In the future, return a variant or some other clue 4358 // for the consumer of this Decl to know it doesn't own it. 4359 // For our current ASTs this shouldn't be a problem, but will 4360 // need to be changed with DeclGroups. 4361 if (TUK == TUK_Reference || TUK == TUK_Friend) 4362 return DeclPtrTy::make(PrevDecl); 4363 4364 // Diagnose attempts to redefine a tag. 4365 if (TUK == TUK_Definition) { 4366 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4367 // If we're defining a specialization and the previous definition 4368 // is from an implicit instantiation, don't emit an error 4369 // here; we'll catch this in the general case below. 4370 if (!isExplicitSpecialization || 4371 !isa<CXXRecordDecl>(Def) || 4372 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4373 == TSK_ExplicitSpecialization) { 4374 Diag(NameLoc, diag::err_redefinition) << Name; 4375 Diag(Def->getLocation(), diag::note_previous_definition); 4376 // If this is a redefinition, recover by making this 4377 // struct be anonymous, which will make any later 4378 // references get the previous definition. 4379 Name = 0; 4380 PrevDecl = 0; 4381 Invalid = true; 4382 } 4383 } else { 4384 // If the type is currently being defined, complain 4385 // about a nested redefinition. 4386 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4387 if (Tag->isBeingDefined()) { 4388 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4389 Diag(PrevTagDecl->getLocation(), 4390 diag::note_previous_definition); 4391 Name = 0; 4392 PrevDecl = 0; 4393 Invalid = true; 4394 } 4395 } 4396 4397 // Okay, this is definition of a previously declared or referenced 4398 // tag PrevDecl. We're going to create a new Decl for it. 4399 } 4400 } 4401 // If we get here we have (another) forward declaration or we 4402 // have a definition. Just create a new decl. 4403 4404 } else { 4405 // If we get here, this is a definition of a new tag type in a nested 4406 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4407 // new decl/type. We set PrevDecl to NULL so that the entities 4408 // have distinct types. 4409 PrevDecl = 0; 4410 } 4411 // If we get here, we're going to create a new Decl. If PrevDecl 4412 // is non-NULL, it's a definition of the tag declared by 4413 // PrevDecl. If it's NULL, we have a new definition. 4414 } else { 4415 // PrevDecl is a namespace, template, or anything else 4416 // that lives in the IDNS_Tag identifier namespace. 4417 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4418 // The tag name clashes with a namespace name, issue an error and 4419 // recover by making this tag be anonymous. 4420 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4421 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4422 Name = 0; 4423 PrevDecl = 0; 4424 Invalid = true; 4425 } else { 4426 // The existing declaration isn't relevant to us; we're in a 4427 // new scope, so clear out the previous declaration. 4428 PrevDecl = 0; 4429 } 4430 } 4431 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4432 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4433 // C++ [basic.scope.pdecl]p5: 4434 // -- for an elaborated-type-specifier of the form 4435 // 4436 // class-key identifier 4437 // 4438 // if the elaborated-type-specifier is used in the 4439 // decl-specifier-seq or parameter-declaration-clause of a 4440 // function defined in namespace scope, the identifier is 4441 // declared as a class-name in the namespace that contains 4442 // the declaration; otherwise, except as a friend 4443 // declaration, the identifier is declared in the smallest 4444 // non-class, non-function-prototype scope that contains the 4445 // declaration. 4446 // 4447 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4448 // C structs and unions. 4449 // 4450 // GNU C also supports this behavior as part of its incomplete 4451 // enum types extension, while GNU C++ does not. 4452 // 4453 // Find the context where we'll be declaring the tag. 4454 // FIXME: We would like to maintain the current DeclContext as the 4455 // lexical context, 4456 while (SearchDC->isRecord()) 4457 SearchDC = SearchDC->getParent(); 4458 4459 // Find the scope where we'll be declaring the tag. 4460 while (S->isClassScope() || 4461 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4462 ((S->getFlags() & Scope::DeclScope) == 0) || 4463 (S->getEntity() && 4464 ((DeclContext *)S->getEntity())->isTransparentContext())) 4465 S = S->getParent(); 4466 4467 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4468 // C++ [namespace.memdef]p3: 4469 // If a friend declaration in a non-local class first declares a 4470 // class or function, the friend class or function is a member of 4471 // the innermost enclosing namespace. 4472 while (!SearchDC->isFileContext()) 4473 SearchDC = SearchDC->getParent(); 4474 4475 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4476 while (S->getEntity() != SearchDC) 4477 S = S->getParent(); 4478 } 4479 4480CreateNewDecl: 4481 4482 // If there is an identifier, use the location of the identifier as the 4483 // location of the decl, otherwise use the location of the struct/union 4484 // keyword. 4485 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4486 4487 // Otherwise, create a new declaration. If there is a previous 4488 // declaration of the same entity, the two will be linked via 4489 // PrevDecl. 4490 TagDecl *New; 4491 4492 if (Kind == TagDecl::TK_enum) { 4493 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4494 // enum X { A, B, C } D; D should chain to X. 4495 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4496 cast_or_null<EnumDecl>(PrevDecl)); 4497 // If this is an undefined enum, warn. 4498 if (TUK != TUK_Definition && !Invalid) { 4499 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4500 : diag::ext_forward_ref_enum; 4501 Diag(Loc, DK); 4502 } 4503 } else { 4504 // struct/union/class 4505 4506 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4507 // struct X { int A; } D; D should chain to X. 4508 if (getLangOptions().CPlusPlus) { 4509 // FIXME: Look for a way to use RecordDecl for simple structs. 4510 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4511 cast_or_null<CXXRecordDecl>(PrevDecl)); 4512 4513 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4514 StdBadAlloc = cast<CXXRecordDecl>(New); 4515 } else 4516 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4517 cast_or_null<RecordDecl>(PrevDecl)); 4518 } 4519 4520 if (Kind != TagDecl::TK_enum) { 4521 // Handle #pragma pack: if the #pragma pack stack has non-default 4522 // alignment, make up a packed attribute for this decl. These 4523 // attributes are checked when the ASTContext lays out the 4524 // structure. 4525 // 4526 // It is important for implementing the correct semantics that this 4527 // happen here (in act on tag decl). The #pragma pack stack is 4528 // maintained as a result of parser callbacks which can occur at 4529 // many points during the parsing of a struct declaration (because 4530 // the #pragma tokens are effectively skipped over during the 4531 // parsing of the struct). 4532 if (unsigned Alignment = getPragmaPackAlignment()) 4533 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4534 } 4535 4536 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4537 // C++ [dcl.typedef]p3: 4538 // [...] Similarly, in a given scope, a class or enumeration 4539 // shall not be declared with the same name as a typedef-name 4540 // that is declared in that scope and refers to a type other 4541 // than the class or enumeration itself. 4542 LookupResult Lookup; 4543 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4544 TypedefDecl *PrevTypedef = 0; 4545 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4546 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4547 4548 NamedDecl *PrevTypedefNamed = PrevTypedef; 4549 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4550 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4551 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4552 Diag(Loc, diag::err_tag_definition_of_typedef) 4553 << Context.getTypeDeclType(New) 4554 << PrevTypedef->getUnderlyingType(); 4555 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4556 Invalid = true; 4557 } 4558 } 4559 4560 // If this is a specialization of a member class (of a class template), 4561 // check the specialization. 4562 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4563 Invalid = true; 4564 4565 if (Invalid) 4566 New->setInvalidDecl(); 4567 4568 if (Attr) 4569 ProcessDeclAttributeList(S, New, Attr); 4570 4571 // If we're declaring or defining a tag in function prototype scope 4572 // in C, note that this type can only be used within the function. 4573 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4574 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4575 4576 // Set the lexical context. If the tag has a C++ scope specifier, the 4577 // lexical context will be different from the semantic context. 4578 New->setLexicalDeclContext(CurContext); 4579 4580 // Mark this as a friend decl if applicable. 4581 if (TUK == TUK_Friend) 4582 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4583 4584 // Set the access specifier. 4585 if (!Invalid && TUK != TUK_Friend) 4586 SetMemberAccessSpecifier(New, PrevDecl, AS); 4587 4588 if (TUK == TUK_Definition) 4589 New->startDefinition(); 4590 4591 // If this has an identifier, add it to the scope stack. 4592 if (TUK == TUK_Friend) { 4593 // We might be replacing an existing declaration in the lookup tables; 4594 // if so, borrow its access specifier. 4595 if (PrevDecl) 4596 New->setAccess(PrevDecl->getAccess()); 4597 4598 // Friend tag decls are visible in fairly strange ways. 4599 if (!CurContext->isDependentContext()) { 4600 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4601 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4602 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4603 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4604 } 4605 } else if (Name) { 4606 S = getNonFieldDeclScope(S); 4607 PushOnScopeChains(New, S); 4608 } else { 4609 CurContext->addDecl(New); 4610 } 4611 4612 // If this is the C FILE type, notify the AST context. 4613 if (IdentifierInfo *II = New->getIdentifier()) 4614 if (!New->isInvalidDecl() && 4615 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4616 II->isStr("FILE")) 4617 Context.setFILEDecl(New); 4618 4619 OwnedDecl = true; 4620 return DeclPtrTy::make(New); 4621} 4622 4623void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4624 AdjustDeclIfTemplate(TagD); 4625 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4626 4627 // Enter the tag context. 4628 PushDeclContext(S, Tag); 4629 4630 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4631 FieldCollector->StartClass(); 4632 4633 if (Record->getIdentifier()) { 4634 // C++ [class]p2: 4635 // [...] The class-name is also inserted into the scope of the 4636 // class itself; this is known as the injected-class-name. For 4637 // purposes of access checking, the injected-class-name is treated 4638 // as if it were a public member name. 4639 CXXRecordDecl *InjectedClassName 4640 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4641 CurContext, Record->getLocation(), 4642 Record->getIdentifier(), 4643 Record->getTagKeywordLoc(), 4644 Record); 4645 InjectedClassName->setImplicit(); 4646 InjectedClassName->setAccess(AS_public); 4647 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4648 InjectedClassName->setDescribedClassTemplate(Template); 4649 PushOnScopeChains(InjectedClassName, S); 4650 assert(InjectedClassName->isInjectedClassName() && 4651 "Broken injected-class-name"); 4652 } 4653 } 4654} 4655 4656void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4657 SourceLocation RBraceLoc) { 4658 AdjustDeclIfTemplate(TagD); 4659 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4660 Tag->setRBraceLoc(RBraceLoc); 4661 4662 if (isa<CXXRecordDecl>(Tag)) 4663 FieldCollector->FinishClass(); 4664 4665 // Exit this scope of this tag's definition. 4666 PopDeclContext(); 4667 4668 // Notify the consumer that we've defined a tag. 4669 Consumer.HandleTagDeclDefinition(Tag); 4670} 4671 4672// Note that FieldName may be null for anonymous bitfields. 4673bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4674 QualType FieldTy, const Expr *BitWidth, 4675 bool *ZeroWidth) { 4676 // Default to true; that shouldn't confuse checks for emptiness 4677 if (ZeroWidth) 4678 *ZeroWidth = true; 4679 4680 // C99 6.7.2.1p4 - verify the field type. 4681 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4682 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4683 // Handle incomplete types with specific error. 4684 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4685 return true; 4686 if (FieldName) 4687 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4688 << FieldName << FieldTy << BitWidth->getSourceRange(); 4689 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4690 << FieldTy << BitWidth->getSourceRange(); 4691 } 4692 4693 // If the bit-width is type- or value-dependent, don't try to check 4694 // it now. 4695 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4696 return false; 4697 4698 llvm::APSInt Value; 4699 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4700 return true; 4701 4702 if (Value != 0 && ZeroWidth) 4703 *ZeroWidth = false; 4704 4705 // Zero-width bitfield is ok for anonymous field. 4706 if (Value == 0 && FieldName) 4707 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4708 4709 if (Value.isSigned() && Value.isNegative()) { 4710 if (FieldName) 4711 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4712 << FieldName << Value.toString(10); 4713 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4714 << Value.toString(10); 4715 } 4716 4717 if (!FieldTy->isDependentType()) { 4718 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4719 if (Value.getZExtValue() > TypeSize) { 4720 if (FieldName) 4721 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4722 << FieldName << (unsigned)TypeSize; 4723 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4724 << (unsigned)TypeSize; 4725 } 4726 } 4727 4728 return false; 4729} 4730 4731/// ActOnField - Each field of a struct/union/class is passed into this in order 4732/// to create a FieldDecl object for it. 4733Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4734 SourceLocation DeclStart, 4735 Declarator &D, ExprTy *BitfieldWidth) { 4736 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4737 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4738 AS_public); 4739 return DeclPtrTy::make(Res); 4740} 4741 4742/// HandleField - Analyze a field of a C struct or a C++ data member. 4743/// 4744FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4745 SourceLocation DeclStart, 4746 Declarator &D, Expr *BitWidth, 4747 AccessSpecifier AS) { 4748 IdentifierInfo *II = D.getIdentifier(); 4749 SourceLocation Loc = DeclStart; 4750 if (II) Loc = D.getIdentifierLoc(); 4751 4752 DeclaratorInfo *DInfo = 0; 4753 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4754 if (getLangOptions().CPlusPlus) 4755 CheckExtraCXXDefaultArguments(D); 4756 4757 DiagnoseFunctionSpecifiers(D); 4758 4759 if (D.getDeclSpec().isThreadSpecified()) 4760 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4761 4762 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4763 4764 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4765 // Maybe we will complain about the shadowed template parameter. 4766 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4767 // Just pretend that we didn't see the previous declaration. 4768 PrevDecl = 0; 4769 } 4770 4771 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4772 PrevDecl = 0; 4773 4774 bool Mutable 4775 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4776 SourceLocation TSSL = D.getSourceRange().getBegin(); 4777 FieldDecl *NewFD 4778 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4779 AS, PrevDecl, &D); 4780 if (NewFD->isInvalidDecl() && PrevDecl) { 4781 // Don't introduce NewFD into scope; there's already something 4782 // with the same name in the same scope. 4783 } else if (II) { 4784 PushOnScopeChains(NewFD, S); 4785 } else 4786 Record->addDecl(NewFD); 4787 4788 return NewFD; 4789} 4790 4791/// \brief Build a new FieldDecl and check its well-formedness. 4792/// 4793/// This routine builds a new FieldDecl given the fields name, type, 4794/// record, etc. \p PrevDecl should refer to any previous declaration 4795/// with the same name and in the same scope as the field to be 4796/// created. 4797/// 4798/// \returns a new FieldDecl. 4799/// 4800/// \todo The Declarator argument is a hack. It will be removed once 4801FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4802 DeclaratorInfo *DInfo, 4803 RecordDecl *Record, SourceLocation Loc, 4804 bool Mutable, Expr *BitWidth, 4805 SourceLocation TSSL, 4806 AccessSpecifier AS, NamedDecl *PrevDecl, 4807 Declarator *D) { 4808 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4809 bool InvalidDecl = false; 4810 if (D) InvalidDecl = D->isInvalidType(); 4811 4812 // If we receive a broken type, recover by assuming 'int' and 4813 // marking this declaration as invalid. 4814 if (T.isNull()) { 4815 InvalidDecl = true; 4816 T = Context.IntTy; 4817 } 4818 4819 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4820 // than a variably modified type. 4821 if (T->isVariablyModifiedType()) { 4822 bool SizeIsNegative; 4823 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4824 SizeIsNegative); 4825 if (!FixedTy.isNull()) { 4826 Diag(Loc, diag::warn_illegal_constant_array_size); 4827 T = FixedTy; 4828 } else { 4829 if (SizeIsNegative) 4830 Diag(Loc, diag::err_typecheck_negative_array_size); 4831 else 4832 Diag(Loc, diag::err_typecheck_field_variable_size); 4833 InvalidDecl = true; 4834 } 4835 } 4836 4837 // Fields can not have abstract class types 4838 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4839 AbstractFieldType)) 4840 InvalidDecl = true; 4841 4842 bool ZeroWidth = false; 4843 // If this is declared as a bit-field, check the bit-field. 4844 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4845 InvalidDecl = true; 4846 DeleteExpr(BitWidth); 4847 BitWidth = 0; 4848 ZeroWidth = false; 4849 } 4850 4851 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4852 BitWidth, Mutable); 4853 if (InvalidDecl) 4854 NewFD->setInvalidDecl(); 4855 4856 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4857 Diag(Loc, diag::err_duplicate_member) << II; 4858 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4859 NewFD->setInvalidDecl(); 4860 } 4861 4862 if (getLangOptions().CPlusPlus) { 4863 QualType EltTy = Context.getBaseElementType(T); 4864 4865 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4866 4867 if (!T->isPODType()) 4868 CXXRecord->setPOD(false); 4869 if (!ZeroWidth) 4870 CXXRecord->setEmpty(false); 4871 4872 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4873 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4874 4875 if (!RDecl->hasTrivialConstructor()) 4876 CXXRecord->setHasTrivialConstructor(false); 4877 if (!RDecl->hasTrivialCopyConstructor()) 4878 CXXRecord->setHasTrivialCopyConstructor(false); 4879 if (!RDecl->hasTrivialCopyAssignment()) 4880 CXXRecord->setHasTrivialCopyAssignment(false); 4881 if (!RDecl->hasTrivialDestructor()) 4882 CXXRecord->setHasTrivialDestructor(false); 4883 4884 // C++ 9.5p1: An object of a class with a non-trivial 4885 // constructor, a non-trivial copy constructor, a non-trivial 4886 // destructor, or a non-trivial copy assignment operator 4887 // cannot be a member of a union, nor can an array of such 4888 // objects. 4889 // TODO: C++0x alters this restriction significantly. 4890 if (Record->isUnion()) { 4891 // We check for copy constructors before constructors 4892 // because otherwise we'll never get complaints about 4893 // copy constructors. 4894 4895 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4896 4897 CXXSpecialMember member; 4898 if (!RDecl->hasTrivialCopyConstructor()) 4899 member = CXXCopyConstructor; 4900 else if (!RDecl->hasTrivialConstructor()) 4901 member = CXXDefaultConstructor; 4902 else if (!RDecl->hasTrivialCopyAssignment()) 4903 member = CXXCopyAssignment; 4904 else if (!RDecl->hasTrivialDestructor()) 4905 member = CXXDestructor; 4906 else 4907 member = invalid; 4908 4909 if (member != invalid) { 4910 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4911 DiagnoseNontrivial(RT, member); 4912 NewFD->setInvalidDecl(); 4913 } 4914 } 4915 } 4916 } 4917 4918 // FIXME: We need to pass in the attributes given an AST 4919 // representation, not a parser representation. 4920 if (D) 4921 // FIXME: What to pass instead of TUScope? 4922 ProcessDeclAttributes(TUScope, NewFD, *D); 4923 4924 if (T.isObjCGCWeak()) 4925 Diag(Loc, diag::warn_attribute_weak_on_field); 4926 4927 NewFD->setAccess(AS); 4928 4929 // C++ [dcl.init.aggr]p1: 4930 // An aggregate is an array or a class (clause 9) with [...] no 4931 // private or protected non-static data members (clause 11). 4932 // A POD must be an aggregate. 4933 if (getLangOptions().CPlusPlus && 4934 (AS == AS_private || AS == AS_protected)) { 4935 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4936 CXXRecord->setAggregate(false); 4937 CXXRecord->setPOD(false); 4938 } 4939 4940 return NewFD; 4941} 4942 4943/// DiagnoseNontrivial - Given that a class has a non-trivial 4944/// special member, figure out why. 4945void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4946 QualType QT(T, 0U); 4947 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4948 4949 // Check whether the member was user-declared. 4950 switch (member) { 4951 case CXXDefaultConstructor: 4952 if (RD->hasUserDeclaredConstructor()) { 4953 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4954 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 4955 const FunctionDecl *body = 0; 4956 ci->getBody(body); 4957 if (!body || 4958 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 4959 SourceLocation CtorLoc = ci->getLocation(); 4960 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4961 return; 4962 } 4963 } 4964 4965 assert(0 && "found no user-declared constructors"); 4966 return; 4967 } 4968 break; 4969 4970 case CXXCopyConstructor: 4971 if (RD->hasUserDeclaredCopyConstructor()) { 4972 SourceLocation CtorLoc = 4973 RD->getCopyConstructor(Context, 0)->getLocation(); 4974 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4975 return; 4976 } 4977 break; 4978 4979 case CXXCopyAssignment: 4980 if (RD->hasUserDeclaredCopyAssignment()) { 4981 // FIXME: this should use the location of the copy 4982 // assignment, not the type. 4983 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4984 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4985 return; 4986 } 4987 break; 4988 4989 case CXXDestructor: 4990 if (RD->hasUserDeclaredDestructor()) { 4991 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4992 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4993 return; 4994 } 4995 break; 4996 } 4997 4998 typedef CXXRecordDecl::base_class_iterator base_iter; 4999 5000 // Virtual bases and members inhibit trivial copying/construction, 5001 // but not trivial destruction. 5002 if (member != CXXDestructor) { 5003 // Check for virtual bases. vbases includes indirect virtual bases, 5004 // so we just iterate through the direct bases. 5005 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5006 if (bi->isVirtual()) { 5007 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5008 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5009 return; 5010 } 5011 5012 // Check for virtual methods. 5013 typedef CXXRecordDecl::method_iterator meth_iter; 5014 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5015 ++mi) { 5016 if (mi->isVirtual()) { 5017 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5018 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5019 return; 5020 } 5021 } 5022 } 5023 5024 bool (CXXRecordDecl::*hasTrivial)() const; 5025 switch (member) { 5026 case CXXDefaultConstructor: 5027 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5028 case CXXCopyConstructor: 5029 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5030 case CXXCopyAssignment: 5031 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5032 case CXXDestructor: 5033 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5034 default: 5035 assert(0 && "unexpected special member"); return; 5036 } 5037 5038 // Check for nontrivial bases (and recurse). 5039 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5040 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5041 assert(BaseRT && "Don't know how to handle dependent bases"); 5042 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5043 if (!(BaseRecTy->*hasTrivial)()) { 5044 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5045 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5046 DiagnoseNontrivial(BaseRT, member); 5047 return; 5048 } 5049 } 5050 5051 // Check for nontrivial members (and recurse). 5052 typedef RecordDecl::field_iterator field_iter; 5053 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5054 ++fi) { 5055 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5056 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5057 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5058 5059 if (!(EltRD->*hasTrivial)()) { 5060 SourceLocation FLoc = (*fi)->getLocation(); 5061 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5062 DiagnoseNontrivial(EltRT, member); 5063 return; 5064 } 5065 } 5066 } 5067 5068 assert(0 && "found no explanation for non-trivial member"); 5069} 5070 5071/// TranslateIvarVisibility - Translate visibility from a token ID to an 5072/// AST enum value. 5073static ObjCIvarDecl::AccessControl 5074TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5075 switch (ivarVisibility) { 5076 default: assert(0 && "Unknown visitibility kind"); 5077 case tok::objc_private: return ObjCIvarDecl::Private; 5078 case tok::objc_public: return ObjCIvarDecl::Public; 5079 case tok::objc_protected: return ObjCIvarDecl::Protected; 5080 case tok::objc_package: return ObjCIvarDecl::Package; 5081 } 5082} 5083 5084/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5085/// in order to create an IvarDecl object for it. 5086Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5087 SourceLocation DeclStart, 5088 DeclPtrTy IntfDecl, 5089 Declarator &D, ExprTy *BitfieldWidth, 5090 tok::ObjCKeywordKind Visibility) { 5091 5092 IdentifierInfo *II = D.getIdentifier(); 5093 Expr *BitWidth = (Expr*)BitfieldWidth; 5094 SourceLocation Loc = DeclStart; 5095 if (II) Loc = D.getIdentifierLoc(); 5096 5097 // FIXME: Unnamed fields can be handled in various different ways, for 5098 // example, unnamed unions inject all members into the struct namespace! 5099 5100 DeclaratorInfo *DInfo = 0; 5101 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5102 5103 if (BitWidth) { 5104 // 6.7.2.1p3, 6.7.2.1p4 5105 if (VerifyBitField(Loc, II, T, BitWidth)) { 5106 D.setInvalidType(); 5107 DeleteExpr(BitWidth); 5108 BitWidth = 0; 5109 } 5110 } else { 5111 // Not a bitfield. 5112 5113 // validate II. 5114 5115 } 5116 5117 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5118 // than a variably modified type. 5119 if (T->isVariablyModifiedType()) { 5120 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5121 D.setInvalidType(); 5122 } 5123 5124 // Get the visibility (access control) for this ivar. 5125 ObjCIvarDecl::AccessControl ac = 5126 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5127 : ObjCIvarDecl::None; 5128 // Must set ivar's DeclContext to its enclosing interface. 5129 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5130 DeclContext *EnclosingContext; 5131 if (ObjCImplementationDecl *IMPDecl = 5132 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5133 // Case of ivar declared in an implementation. Context is that of its class. 5134 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5135 assert(IDecl && "No class- ActOnIvar"); 5136 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5137 } else 5138 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5139 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5140 5141 // Construct the decl. 5142 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5143 EnclosingContext, Loc, II, T, 5144 DInfo, ac, (Expr *)BitfieldWidth); 5145 5146 if (II) { 5147 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5148 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5149 && !isa<TagDecl>(PrevDecl)) { 5150 Diag(Loc, diag::err_duplicate_member) << II; 5151 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5152 NewID->setInvalidDecl(); 5153 } 5154 } 5155 5156 // Process attributes attached to the ivar. 5157 ProcessDeclAttributes(S, NewID, D); 5158 5159 if (D.isInvalidType()) 5160 NewID->setInvalidDecl(); 5161 5162 if (II) { 5163 // FIXME: When interfaces are DeclContexts, we'll need to add 5164 // these to the interface. 5165 S->AddDecl(DeclPtrTy::make(NewID)); 5166 IdResolver.AddDecl(NewID); 5167 } 5168 5169 return DeclPtrTy::make(NewID); 5170} 5171 5172void Sema::ActOnFields(Scope* S, 5173 SourceLocation RecLoc, DeclPtrTy RecDecl, 5174 DeclPtrTy *Fields, unsigned NumFields, 5175 SourceLocation LBrac, SourceLocation RBrac, 5176 AttributeList *Attr) { 5177 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5178 assert(EnclosingDecl && "missing record or interface decl"); 5179 5180 // If the decl this is being inserted into is invalid, then it may be a 5181 // redeclaration or some other bogus case. Don't try to add fields to it. 5182 if (EnclosingDecl->isInvalidDecl()) { 5183 // FIXME: Deallocate fields? 5184 return; 5185 } 5186 5187 5188 // Verify that all the fields are okay. 5189 unsigned NumNamedMembers = 0; 5190 llvm::SmallVector<FieldDecl*, 32> RecFields; 5191 5192 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5193 for (unsigned i = 0; i != NumFields; ++i) { 5194 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5195 5196 // Get the type for the field. 5197 Type *FDTy = FD->getType().getTypePtr(); 5198 5199 if (!FD->isAnonymousStructOrUnion()) { 5200 // Remember all fields written by the user. 5201 RecFields.push_back(FD); 5202 } 5203 5204 // If the field is already invalid for some reason, don't emit more 5205 // diagnostics about it. 5206 if (FD->isInvalidDecl()) 5207 continue; 5208 5209 // C99 6.7.2.1p2: 5210 // A structure or union shall not contain a member with 5211 // incomplete or function type (hence, a structure shall not 5212 // contain an instance of itself, but may contain a pointer to 5213 // an instance of itself), except that the last member of a 5214 // structure with more than one named member may have incomplete 5215 // array type; such a structure (and any union containing, 5216 // possibly recursively, a member that is such a structure) 5217 // shall not be a member of a structure or an element of an 5218 // array. 5219 if (FDTy->isFunctionType()) { 5220 // Field declared as a function. 5221 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5222 << FD->getDeclName(); 5223 FD->setInvalidDecl(); 5224 EnclosingDecl->setInvalidDecl(); 5225 continue; 5226 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5227 Record && Record->isStruct()) { 5228 // Flexible array member. 5229 if (NumNamedMembers < 1) { 5230 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5231 << FD->getDeclName(); 5232 FD->setInvalidDecl(); 5233 EnclosingDecl->setInvalidDecl(); 5234 continue; 5235 } 5236 // Okay, we have a legal flexible array member at the end of the struct. 5237 if (Record) 5238 Record->setHasFlexibleArrayMember(true); 5239 } else if (!FDTy->isDependentType() && 5240 RequireCompleteType(FD->getLocation(), FD->getType(), 5241 diag::err_field_incomplete)) { 5242 // Incomplete type 5243 FD->setInvalidDecl(); 5244 EnclosingDecl->setInvalidDecl(); 5245 continue; 5246 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5247 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5248 // If this is a member of a union, then entire union becomes "flexible". 5249 if (Record && Record->isUnion()) { 5250 Record->setHasFlexibleArrayMember(true); 5251 } else { 5252 // If this is a struct/class and this is not the last element, reject 5253 // it. Note that GCC supports variable sized arrays in the middle of 5254 // structures. 5255 if (i != NumFields-1) 5256 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5257 << FD->getDeclName() << FD->getType(); 5258 else { 5259 // We support flexible arrays at the end of structs in 5260 // other structs as an extension. 5261 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5262 << FD->getDeclName(); 5263 if (Record) 5264 Record->setHasFlexibleArrayMember(true); 5265 } 5266 } 5267 } 5268 if (Record && FDTTy->getDecl()->hasObjectMember()) 5269 Record->setHasObjectMember(true); 5270 } else if (FDTy->isObjCInterfaceType()) { 5271 /// A field cannot be an Objective-c object 5272 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5273 FD->setInvalidDecl(); 5274 EnclosingDecl->setInvalidDecl(); 5275 continue; 5276 } else if (getLangOptions().ObjC1 && 5277 getLangOptions().getGCMode() != LangOptions::NonGC && 5278 Record && 5279 (FD->getType()->isObjCObjectPointerType() || 5280 FD->getType().isObjCGCStrong())) 5281 Record->setHasObjectMember(true); 5282 // Keep track of the number of named members. 5283 if (FD->getIdentifier()) 5284 ++NumNamedMembers; 5285 } 5286 5287 // Okay, we successfully defined 'Record'. 5288 if (Record) { 5289 Record->completeDefinition(Context); 5290 } else { 5291 ObjCIvarDecl **ClsFields = 5292 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5293 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5294 ID->setIVarList(ClsFields, RecFields.size(), Context); 5295 ID->setLocEnd(RBrac); 5296 // Add ivar's to class's DeclContext. 5297 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5298 ClsFields[i]->setLexicalDeclContext(ID); 5299 ID->addDecl(ClsFields[i]); 5300 } 5301 // Must enforce the rule that ivars in the base classes may not be 5302 // duplicates. 5303 if (ID->getSuperClass()) { 5304 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5305 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5306 ObjCIvarDecl* Ivar = (*IVI); 5307 5308 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5309 ObjCIvarDecl* prevIvar = 5310 ID->getSuperClass()->lookupInstanceVariable(II); 5311 if (prevIvar) { 5312 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5313 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5314 } 5315 } 5316 } 5317 } 5318 } else if (ObjCImplementationDecl *IMPDecl = 5319 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5320 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5321 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5322 // Ivar declared in @implementation never belongs to the implementation. 5323 // Only it is in implementation's lexical context. 5324 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5325 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5326 } 5327 } 5328 5329 if (Attr) 5330 ProcessDeclAttributeList(S, Record, Attr); 5331} 5332 5333EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5334 EnumConstantDecl *LastEnumConst, 5335 SourceLocation IdLoc, 5336 IdentifierInfo *Id, 5337 ExprArg val) { 5338 Expr *Val = (Expr *)val.get(); 5339 5340 llvm::APSInt EnumVal(32); 5341 QualType EltTy; 5342 if (Val && !Val->isTypeDependent()) { 5343 // Make sure to promote the operand type to int. 5344 UsualUnaryConversions(Val); 5345 if (Val != val.get()) { 5346 val.release(); 5347 val = Val; 5348 } 5349 5350 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5351 SourceLocation ExpLoc; 5352 if (!Val->isValueDependent() && 5353 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5354 Val = 0; 5355 } else { 5356 EltTy = Val->getType(); 5357 } 5358 } 5359 5360 if (!Val) { 5361 if (LastEnumConst) { 5362 // Assign the last value + 1. 5363 EnumVal = LastEnumConst->getInitVal(); 5364 ++EnumVal; 5365 5366 // Check for overflow on increment. 5367 if (EnumVal < LastEnumConst->getInitVal()) 5368 Diag(IdLoc, diag::warn_enum_value_overflow); 5369 5370 EltTy = LastEnumConst->getType(); 5371 } else { 5372 // First value, set to zero. 5373 EltTy = Context.IntTy; 5374 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5375 } 5376 } 5377 5378 val.release(); 5379 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5380 Val, EnumVal); 5381} 5382 5383 5384Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5385 DeclPtrTy lastEnumConst, 5386 SourceLocation IdLoc, 5387 IdentifierInfo *Id, 5388 SourceLocation EqualLoc, ExprTy *val) { 5389 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5390 EnumConstantDecl *LastEnumConst = 5391 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5392 Expr *Val = static_cast<Expr*>(val); 5393 5394 // The scope passed in may not be a decl scope. Zip up the scope tree until 5395 // we find one that is. 5396 S = getNonFieldDeclScope(S); 5397 5398 // Verify that there isn't already something declared with this name in this 5399 // scope. 5400 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5401 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5402 // Maybe we will complain about the shadowed template parameter. 5403 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5404 // Just pretend that we didn't see the previous declaration. 5405 PrevDecl = 0; 5406 } 5407 5408 if (PrevDecl) { 5409 // When in C++, we may get a TagDecl with the same name; in this case the 5410 // enum constant will 'hide' the tag. 5411 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5412 "Received TagDecl when not in C++!"); 5413 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5414 if (isa<EnumConstantDecl>(PrevDecl)) 5415 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5416 else 5417 Diag(IdLoc, diag::err_redefinition) << Id; 5418 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5419 if (Val) Val->Destroy(Context); 5420 return DeclPtrTy(); 5421 } 5422 } 5423 5424 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5425 IdLoc, Id, Owned(Val)); 5426 5427 // Register this decl in the current scope stack. 5428 if (New) 5429 PushOnScopeChains(New, S); 5430 5431 return DeclPtrTy::make(New); 5432} 5433 5434void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5435 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5436 DeclPtrTy *Elements, unsigned NumElements, 5437 Scope *S, AttributeList *Attr) { 5438 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5439 QualType EnumType = Context.getTypeDeclType(Enum); 5440 5441 if (Attr) 5442 ProcessDeclAttributeList(S, Enum, Attr); 5443 5444 // TODO: If the result value doesn't fit in an int, it must be a long or long 5445 // long value. ISO C does not support this, but GCC does as an extension, 5446 // emit a warning. 5447 unsigned IntWidth = Context.Target.getIntWidth(); 5448 unsigned CharWidth = Context.Target.getCharWidth(); 5449 unsigned ShortWidth = Context.Target.getShortWidth(); 5450 5451 // Verify that all the values are okay, compute the size of the values, and 5452 // reverse the list. 5453 unsigned NumNegativeBits = 0; 5454 unsigned NumPositiveBits = 0; 5455 5456 // Keep track of whether all elements have type int. 5457 bool AllElementsInt = true; 5458 5459 for (unsigned i = 0; i != NumElements; ++i) { 5460 EnumConstantDecl *ECD = 5461 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5462 if (!ECD) continue; // Already issued a diagnostic. 5463 5464 // If the enum value doesn't fit in an int, emit an extension warning. 5465 const llvm::APSInt &InitVal = ECD->getInitVal(); 5466 assert(InitVal.getBitWidth() >= IntWidth && 5467 "Should have promoted value to int"); 5468 if (InitVal.getBitWidth() > IntWidth) { 5469 llvm::APSInt V(InitVal); 5470 V.trunc(IntWidth); 5471 V.extend(InitVal.getBitWidth()); 5472 if (V != InitVal) 5473 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5474 << InitVal.toString(10); 5475 } 5476 5477 // Keep track of the size of positive and negative values. 5478 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5479 NumPositiveBits = std::max(NumPositiveBits, 5480 (unsigned)InitVal.getActiveBits()); 5481 else 5482 NumNegativeBits = std::max(NumNegativeBits, 5483 (unsigned)InitVal.getMinSignedBits()); 5484 5485 // Keep track of whether every enum element has type int (very commmon). 5486 if (AllElementsInt) 5487 AllElementsInt = ECD->getType() == Context.IntTy; 5488 } 5489 5490 // Figure out the type that should be used for this enum. 5491 // FIXME: Support -fshort-enums. 5492 QualType BestType; 5493 unsigned BestWidth; 5494 5495 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5496 5497 if (NumNegativeBits) { 5498 // If there is a negative value, figure out the smallest integer type (of 5499 // int/long/longlong) that fits. 5500 // If it's packed, check also if it fits a char or a short. 5501 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5502 BestType = Context.SignedCharTy; 5503 BestWidth = CharWidth; 5504 } else if (Packed && NumNegativeBits <= ShortWidth && 5505 NumPositiveBits < ShortWidth) { 5506 BestType = Context.ShortTy; 5507 BestWidth = ShortWidth; 5508 } 5509 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5510 BestType = Context.IntTy; 5511 BestWidth = IntWidth; 5512 } else { 5513 BestWidth = Context.Target.getLongWidth(); 5514 5515 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5516 BestType = Context.LongTy; 5517 else { 5518 BestWidth = Context.Target.getLongLongWidth(); 5519 5520 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5521 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5522 BestType = Context.LongLongTy; 5523 } 5524 } 5525 } else { 5526 // If there is no negative value, figure out which of uint, ulong, ulonglong 5527 // fits. 5528 // If it's packed, check also if it fits a char or a short. 5529 if (Packed && NumPositiveBits <= CharWidth) { 5530 BestType = Context.UnsignedCharTy; 5531 BestWidth = CharWidth; 5532 } else if (Packed && NumPositiveBits <= ShortWidth) { 5533 BestType = Context.UnsignedShortTy; 5534 BestWidth = ShortWidth; 5535 } 5536 else if (NumPositiveBits <= IntWidth) { 5537 BestType = Context.UnsignedIntTy; 5538 BestWidth = IntWidth; 5539 } else if (NumPositiveBits <= 5540 (BestWidth = Context.Target.getLongWidth())) { 5541 BestType = Context.UnsignedLongTy; 5542 } else { 5543 BestWidth = Context.Target.getLongLongWidth(); 5544 assert(NumPositiveBits <= BestWidth && 5545 "How could an initializer get larger than ULL?"); 5546 BestType = Context.UnsignedLongLongTy; 5547 } 5548 } 5549 5550 // Loop over all of the enumerator constants, changing their types to match 5551 // the type of the enum if needed. 5552 for (unsigned i = 0; i != NumElements; ++i) { 5553 EnumConstantDecl *ECD = 5554 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5555 if (!ECD) continue; // Already issued a diagnostic. 5556 5557 // Standard C says the enumerators have int type, but we allow, as an 5558 // extension, the enumerators to be larger than int size. If each 5559 // enumerator value fits in an int, type it as an int, otherwise type it the 5560 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5561 // that X has type 'int', not 'unsigned'. 5562 if (ECD->getType() == Context.IntTy) { 5563 // Make sure the init value is signed. 5564 llvm::APSInt IV = ECD->getInitVal(); 5565 IV.setIsSigned(true); 5566 ECD->setInitVal(IV); 5567 5568 if (getLangOptions().CPlusPlus) 5569 // C++ [dcl.enum]p4: Following the closing brace of an 5570 // enum-specifier, each enumerator has the type of its 5571 // enumeration. 5572 ECD->setType(EnumType); 5573 continue; // Already int type. 5574 } 5575 5576 // Determine whether the value fits into an int. 5577 llvm::APSInt InitVal = ECD->getInitVal(); 5578 bool FitsInInt; 5579 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5580 FitsInInt = InitVal.getActiveBits() < IntWidth; 5581 else 5582 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5583 5584 // If it fits into an integer type, force it. Otherwise force it to match 5585 // the enum decl type. 5586 QualType NewTy; 5587 unsigned NewWidth; 5588 bool NewSign; 5589 if (FitsInInt) { 5590 NewTy = Context.IntTy; 5591 NewWidth = IntWidth; 5592 NewSign = true; 5593 } else if (ECD->getType() == BestType) { 5594 // Already the right type! 5595 if (getLangOptions().CPlusPlus) 5596 // C++ [dcl.enum]p4: Following the closing brace of an 5597 // enum-specifier, each enumerator has the type of its 5598 // enumeration. 5599 ECD->setType(EnumType); 5600 continue; 5601 } else { 5602 NewTy = BestType; 5603 NewWidth = BestWidth; 5604 NewSign = BestType->isSignedIntegerType(); 5605 } 5606 5607 // Adjust the APSInt value. 5608 InitVal.extOrTrunc(NewWidth); 5609 InitVal.setIsSigned(NewSign); 5610 ECD->setInitVal(InitVal); 5611 5612 // Adjust the Expr initializer and type. 5613 if (ECD->getInitExpr()) 5614 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5615 CastExpr::CK_IntegralCast, 5616 ECD->getInitExpr(), 5617 /*isLvalue=*/false)); 5618 if (getLangOptions().CPlusPlus) 5619 // C++ [dcl.enum]p4: Following the closing brace of an 5620 // enum-specifier, each enumerator has the type of its 5621 // enumeration. 5622 ECD->setType(EnumType); 5623 else 5624 ECD->setType(NewTy); 5625 } 5626 5627 Enum->completeDefinition(Context, BestType); 5628} 5629 5630Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5631 ExprArg expr) { 5632 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5633 5634 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5635 Loc, AsmString); 5636 CurContext->addDecl(New); 5637 return DeclPtrTy::make(New); 5638} 5639 5640void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5641 SourceLocation PragmaLoc, 5642 SourceLocation NameLoc) { 5643 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5644 5645 if (PrevDecl) { 5646 PrevDecl->addAttr(::new (Context) WeakAttr()); 5647 } else { 5648 (void)WeakUndeclaredIdentifiers.insert( 5649 std::pair<IdentifierInfo*,WeakInfo> 5650 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5651 } 5652} 5653 5654void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5655 IdentifierInfo* AliasName, 5656 SourceLocation PragmaLoc, 5657 SourceLocation NameLoc, 5658 SourceLocation AliasNameLoc) { 5659 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5660 WeakInfo W = WeakInfo(Name, NameLoc); 5661 5662 if (PrevDecl) { 5663 if (!PrevDecl->hasAttr<AliasAttr>()) 5664 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5665 DeclApplyPragmaWeak(TUScope, ND, W); 5666 } else { 5667 (void)WeakUndeclaredIdentifiers.insert( 5668 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5669 } 5670} 5671