SemaDecl.cpp revision 7a128e84006fdabfda4b8bd04f09c2739ed7f824
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 and 1048/// NeverFallThrough iff we never fall off the end of the statement. We assume 1049/// that functions not marked noreturn will return. 1050Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1051 // FIXME: Eventually share this CFG object when we have other warnings based 1052 // of the CFG. This can be done using AnalysisContext. 1053 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1054 1055 // FIXME: They should never return 0, fix that, delete this code. 1056 if (cfg == 0) 1057 return NeverFallThrough; 1058 // The CFG leaves in dead things, and we don't want to dead code paths to 1059 // confuse us, so we mark all live things first. 1060 std::queue<CFGBlock*> workq; 1061 llvm::BitVector live(cfg->getNumBlockIDs()); 1062 // Prep work queue 1063 workq.push(&cfg->getEntry()); 1064 // Solve 1065 while (!workq.empty()) { 1066 CFGBlock *item = workq.front(); 1067 workq.pop(); 1068 live.set(item->getBlockID()); 1069 for (CFGBlock::succ_iterator I=item->succ_begin(), 1070 E=item->succ_end(); 1071 I != E; 1072 ++I) { 1073 if ((*I) && !live[(*I)->getBlockID()]) { 1074 live.set((*I)->getBlockID()); 1075 workq.push(*I); 1076 } 1077 } 1078 } 1079 1080 // Now we know what is live, we check the live precessors of the exit block 1081 // and look for fall through paths, being careful to ignore normal returns, 1082 // and exceptional paths. 1083 bool HasLiveReturn = false; 1084 bool HasFakeEdge = false; 1085 bool HasPlainEdge = false; 1086 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1087 E = cfg->getExit().pred_end(); 1088 I != E; 1089 ++I) { 1090 CFGBlock& B = **I; 1091 if (!live[B.getBlockID()]) 1092 continue; 1093 if (B.size() == 0) { 1094 // A labeled empty statement, or the entry block... 1095 HasPlainEdge = true; 1096 continue; 1097 } 1098 Stmt *S = B[B.size()-1]; 1099 if (isa<ReturnStmt>(S)) { 1100 HasLiveReturn = true; 1101 continue; 1102 } 1103 if (isa<ObjCAtThrowStmt>(S)) { 1104 HasFakeEdge = true; 1105 continue; 1106 } 1107 if (isa<CXXThrowExpr>(S)) { 1108 HasFakeEdge = true; 1109 continue; 1110 } 1111 bool NoReturnEdge = false; 1112 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1113 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1114 if (CEE->getType().getNoReturnAttr()) { 1115 NoReturnEdge = true; 1116 HasFakeEdge = true; 1117 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1118 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1119 if (FD->hasAttr<NoReturnAttr>()) { 1120 NoReturnEdge = true; 1121 HasFakeEdge = true; 1122 } 1123 } 1124 } 1125 } 1126 // FIXME: Add noreturn message sends. 1127 if (NoReturnEdge == false) 1128 HasPlainEdge = true; 1129 } 1130 if (!HasPlainEdge) 1131 return NeverFallThrough; 1132 if (HasFakeEdge || HasLiveReturn) 1133 return MaybeFallThrough; 1134 // This says AlwaysFallThrough for calls to functions that are not marked 1135 // noreturn, that don't return. If people would like this warning to be more 1136 // accurate, such functions should be marked as noreturn. 1137 return AlwaysFallThrough; 1138} 1139 1140/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1141/// function that should return a value. Check that we don't fall off the end 1142/// of a noreturn function. We assume that functions and blocks not marked 1143/// noreturn will return. 1144void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1145 // FIXME: Would be nice if we had a better way to control cascading errors, 1146 // but for now, avoid them. The problem is that when Parse sees: 1147 // int foo() { return a; } 1148 // The return is eaten and the Sema code sees just: 1149 // int foo() { } 1150 // which this code would then warn about. 1151 if (getDiagnostics().hasErrorOccurred()) 1152 return; 1153 1154 bool ReturnsVoid = false; 1155 bool HasNoReturn = false; 1156 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1157 // If the result type of the function is a dependent type, we don't know 1158 // whether it will be void or not, so don't 1159 if (FD->getResultType()->isDependentType()) 1160 return; 1161 if (FD->getResultType()->isVoidType()) 1162 ReturnsVoid = true; 1163 if (FD->hasAttr<NoReturnAttr>()) 1164 HasNoReturn = true; 1165 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1166 if (MD->getResultType()->isVoidType()) 1167 ReturnsVoid = true; 1168 if (MD->hasAttr<NoReturnAttr>()) 1169 HasNoReturn = true; 1170 } 1171 1172 // Short circuit for compilation speed. 1173 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1174 == Diagnostic::Ignored || ReturnsVoid) 1175 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1176 == Diagnostic::Ignored || !HasNoReturn) 1177 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1178 == Diagnostic::Ignored || !ReturnsVoid)) 1179 return; 1180 // FIXME: Function try block 1181 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1182 switch (CheckFallThrough(Body)) { 1183 case MaybeFallThrough: 1184 if (HasNoReturn) 1185 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1186 else if (!ReturnsVoid) 1187 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1188 break; 1189 case AlwaysFallThrough: 1190 if (HasNoReturn) 1191 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1192 else if (!ReturnsVoid) 1193 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1194 break; 1195 case NeverFallThrough: 1196 if (ReturnsVoid && !HasNoReturn) 1197 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1198 break; 1199 } 1200 } 1201} 1202 1203/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1204/// that should return a value. Check that we don't fall off the end of a 1205/// noreturn block. We assume that functions and blocks not marked noreturn 1206/// will return. 1207void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1208 // FIXME: Would be nice if we had a better way to control cascading errors, 1209 // but for now, avoid them. The problem is that when Parse sees: 1210 // int foo() { return a; } 1211 // The return is eaten and the Sema code sees just: 1212 // int foo() { } 1213 // which this code would then warn about. 1214 if (getDiagnostics().hasErrorOccurred()) 1215 return; 1216 bool ReturnsVoid = false; 1217 bool HasNoReturn = false; 1218 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1219 if (FT->getResultType()->isVoidType()) 1220 ReturnsVoid = true; 1221 if (FT->getNoReturnAttr()) 1222 HasNoReturn = true; 1223 } 1224 1225 // Short circuit for compilation speed. 1226 if (ReturnsVoid 1227 && !HasNoReturn 1228 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1229 == Diagnostic::Ignored || !ReturnsVoid)) 1230 return; 1231 // FIXME: Funtion try block 1232 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1233 switch (CheckFallThrough(Body)) { 1234 case MaybeFallThrough: 1235 if (HasNoReturn) 1236 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1237 else if (!ReturnsVoid) 1238 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1239 break; 1240 case AlwaysFallThrough: 1241 if (HasNoReturn) 1242 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1243 else if (!ReturnsVoid) 1244 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1245 break; 1246 case NeverFallThrough: 1247 if (ReturnsVoid) 1248 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1249 break; 1250 } 1251 } 1252} 1253 1254/// CheckParmsForFunctionDef - Check that the parameters of the given 1255/// function are appropriate for the definition of a function. This 1256/// takes care of any checks that cannot be performed on the 1257/// declaration itself, e.g., that the types of each of the function 1258/// parameters are complete. 1259bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1260 bool HasInvalidParm = false; 1261 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1262 ParmVarDecl *Param = FD->getParamDecl(p); 1263 1264 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1265 // function declarator that is part of a function definition of 1266 // that function shall not have incomplete type. 1267 // 1268 // This is also C++ [dcl.fct]p6. 1269 if (!Param->isInvalidDecl() && 1270 RequireCompleteType(Param->getLocation(), Param->getType(), 1271 diag::err_typecheck_decl_incomplete_type)) { 1272 Param->setInvalidDecl(); 1273 HasInvalidParm = true; 1274 } 1275 1276 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1277 // declaration of each parameter shall include an identifier. 1278 if (Param->getIdentifier() == 0 && 1279 !Param->isImplicit() && 1280 !getLangOptions().CPlusPlus) 1281 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1282 } 1283 1284 return HasInvalidParm; 1285} 1286 1287/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1288/// no declarator (e.g. "struct foo;") is parsed. 1289Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1290 // FIXME: Error on auto/register at file scope 1291 // FIXME: Error on inline/virtual/explicit 1292 // FIXME: Error on invalid restrict 1293 // FIXME: Warn on useless __thread 1294 // FIXME: Warn on useless const/volatile 1295 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1296 // FIXME: Warn on useless attributes 1297 Decl *TagD = 0; 1298 TagDecl *Tag = 0; 1299 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1300 DS.getTypeSpecType() == DeclSpec::TST_struct || 1301 DS.getTypeSpecType() == DeclSpec::TST_union || 1302 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1303 TagD = static_cast<Decl *>(DS.getTypeRep()); 1304 1305 if (!TagD) // We probably had an error 1306 return DeclPtrTy(); 1307 1308 // Note that the above type specs guarantee that the 1309 // type rep is a Decl, whereas in many of the others 1310 // it's a Type. 1311 Tag = dyn_cast<TagDecl>(TagD); 1312 } 1313 1314 if (DS.isFriendSpecified()) { 1315 // If we're dealing with a class template decl, assume that the 1316 // template routines are handling it. 1317 if (TagD && isa<ClassTemplateDecl>(TagD)) 1318 return DeclPtrTy(); 1319 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1320 } 1321 1322 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1323 // If there are attributes in the DeclSpec, apply them to the record. 1324 if (const AttributeList *AL = DS.getAttributes()) 1325 ProcessDeclAttributeList(S, Record, AL); 1326 1327 if (!Record->getDeclName() && Record->isDefinition() && 1328 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1329 if (getLangOptions().CPlusPlus || 1330 Record->getDeclContext()->isRecord()) 1331 return BuildAnonymousStructOrUnion(S, DS, Record); 1332 1333 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1334 << DS.getSourceRange(); 1335 } 1336 1337 // Microsoft allows unnamed struct/union fields. Don't complain 1338 // about them. 1339 // FIXME: Should we support Microsoft's extensions in this area? 1340 if (Record->getDeclName() && getLangOptions().Microsoft) 1341 return DeclPtrTy::make(Tag); 1342 } 1343 1344 if (!DS.isMissingDeclaratorOk() && 1345 DS.getTypeSpecType() != DeclSpec::TST_error) { 1346 // Warn about typedefs of enums without names, since this is an 1347 // extension in both Microsoft an GNU. 1348 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1349 Tag && isa<EnumDecl>(Tag)) { 1350 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1351 << DS.getSourceRange(); 1352 return DeclPtrTy::make(Tag); 1353 } 1354 1355 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1356 << DS.getSourceRange(); 1357 return DeclPtrTy(); 1358 } 1359 1360 return DeclPtrTy::make(Tag); 1361} 1362 1363/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1364/// anonymous struct or union AnonRecord into the owning context Owner 1365/// and scope S. This routine will be invoked just after we realize 1366/// that an unnamed union or struct is actually an anonymous union or 1367/// struct, e.g., 1368/// 1369/// @code 1370/// union { 1371/// int i; 1372/// float f; 1373/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1374/// // f into the surrounding scope.x 1375/// @endcode 1376/// 1377/// This routine is recursive, injecting the names of nested anonymous 1378/// structs/unions into the owning context and scope as well. 1379bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1380 RecordDecl *AnonRecord) { 1381 bool Invalid = false; 1382 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1383 FEnd = AnonRecord->field_end(); 1384 F != FEnd; ++F) { 1385 if ((*F)->getDeclName()) { 1386 LookupResult R; 1387 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1388 LookupOrdinaryName, true); 1389 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1390 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1391 // C++ [class.union]p2: 1392 // The names of the members of an anonymous union shall be 1393 // distinct from the names of any other entity in the 1394 // scope in which the anonymous union is declared. 1395 unsigned diagKind 1396 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1397 : diag::err_anonymous_struct_member_redecl; 1398 Diag((*F)->getLocation(), diagKind) 1399 << (*F)->getDeclName(); 1400 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1401 Invalid = true; 1402 } else { 1403 // C++ [class.union]p2: 1404 // For the purpose of name lookup, after the anonymous union 1405 // definition, the members of the anonymous union are 1406 // considered to have been defined in the scope in which the 1407 // anonymous union is declared. 1408 Owner->makeDeclVisibleInContext(*F); 1409 S->AddDecl(DeclPtrTy::make(*F)); 1410 IdResolver.AddDecl(*F); 1411 } 1412 } else if (const RecordType *InnerRecordType 1413 = (*F)->getType()->getAs<RecordType>()) { 1414 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1415 if (InnerRecord->isAnonymousStructOrUnion()) 1416 Invalid = Invalid || 1417 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1418 } 1419 } 1420 1421 return Invalid; 1422} 1423 1424/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1425/// anonymous structure or union. Anonymous unions are a C++ feature 1426/// (C++ [class.union]) and a GNU C extension; anonymous structures 1427/// are a GNU C and GNU C++ extension. 1428Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1429 RecordDecl *Record) { 1430 DeclContext *Owner = Record->getDeclContext(); 1431 1432 // Diagnose whether this anonymous struct/union is an extension. 1433 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1434 Diag(Record->getLocation(), diag::ext_anonymous_union); 1435 else if (!Record->isUnion()) 1436 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1437 1438 // C and C++ require different kinds of checks for anonymous 1439 // structs/unions. 1440 bool Invalid = false; 1441 if (getLangOptions().CPlusPlus) { 1442 const char* PrevSpec = 0; 1443 unsigned DiagID; 1444 // C++ [class.union]p3: 1445 // Anonymous unions declared in a named namespace or in the 1446 // global namespace shall be declared static. 1447 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1448 (isa<TranslationUnitDecl>(Owner) || 1449 (isa<NamespaceDecl>(Owner) && 1450 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1451 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1452 Invalid = true; 1453 1454 // Recover by adding 'static'. 1455 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1456 PrevSpec, DiagID); 1457 } 1458 // C++ [class.union]p3: 1459 // A storage class is not allowed in a declaration of an 1460 // anonymous union in a class scope. 1461 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1462 isa<RecordDecl>(Owner)) { 1463 Diag(DS.getStorageClassSpecLoc(), 1464 diag::err_anonymous_union_with_storage_spec); 1465 Invalid = true; 1466 1467 // Recover by removing the storage specifier. 1468 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1469 PrevSpec, DiagID); 1470 } 1471 1472 // C++ [class.union]p2: 1473 // The member-specification of an anonymous union shall only 1474 // define non-static data members. [Note: nested types and 1475 // functions cannot be declared within an anonymous union. ] 1476 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1477 MemEnd = Record->decls_end(); 1478 Mem != MemEnd; ++Mem) { 1479 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1480 // C++ [class.union]p3: 1481 // An anonymous union shall not have private or protected 1482 // members (clause 11). 1483 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1484 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1485 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1486 Invalid = true; 1487 } 1488 } else if ((*Mem)->isImplicit()) { 1489 // Any implicit members are fine. 1490 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1491 // This is a type that showed up in an 1492 // elaborated-type-specifier inside the anonymous struct or 1493 // union, but which actually declares a type outside of the 1494 // anonymous struct or union. It's okay. 1495 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1496 if (!MemRecord->isAnonymousStructOrUnion() && 1497 MemRecord->getDeclName()) { 1498 // This is a nested type declaration. 1499 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1500 << (int)Record->isUnion(); 1501 Invalid = true; 1502 } 1503 } else { 1504 // We have something that isn't a non-static data 1505 // member. Complain about it. 1506 unsigned DK = diag::err_anonymous_record_bad_member; 1507 if (isa<TypeDecl>(*Mem)) 1508 DK = diag::err_anonymous_record_with_type; 1509 else if (isa<FunctionDecl>(*Mem)) 1510 DK = diag::err_anonymous_record_with_function; 1511 else if (isa<VarDecl>(*Mem)) 1512 DK = diag::err_anonymous_record_with_static; 1513 Diag((*Mem)->getLocation(), DK) 1514 << (int)Record->isUnion(); 1515 Invalid = true; 1516 } 1517 } 1518 } 1519 1520 if (!Record->isUnion() && !Owner->isRecord()) { 1521 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1522 << (int)getLangOptions().CPlusPlus; 1523 Invalid = true; 1524 } 1525 1526 // Mock up a declarator. 1527 Declarator Dc(DS, Declarator::TypeNameContext); 1528 DeclaratorInfo *DInfo = 0; 1529 GetTypeForDeclarator(Dc, S, &DInfo); 1530 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1531 1532 // Create a declaration for this anonymous struct/union. 1533 NamedDecl *Anon = 0; 1534 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1535 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1536 /*IdentifierInfo=*/0, 1537 Context.getTypeDeclType(Record), 1538 DInfo, 1539 /*BitWidth=*/0, /*Mutable=*/false); 1540 Anon->setAccess(AS_public); 1541 if (getLangOptions().CPlusPlus) 1542 FieldCollector->Add(cast<FieldDecl>(Anon)); 1543 } else { 1544 VarDecl::StorageClass SC; 1545 switch (DS.getStorageClassSpec()) { 1546 default: assert(0 && "Unknown storage class!"); 1547 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1548 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1549 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1550 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1551 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1552 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1553 case DeclSpec::SCS_mutable: 1554 // mutable can only appear on non-static class members, so it's always 1555 // an error here 1556 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1557 Invalid = true; 1558 SC = VarDecl::None; 1559 break; 1560 } 1561 1562 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1563 /*IdentifierInfo=*/0, 1564 Context.getTypeDeclType(Record), 1565 DInfo, 1566 SC); 1567 } 1568 Anon->setImplicit(); 1569 1570 // Add the anonymous struct/union object to the current 1571 // context. We'll be referencing this object when we refer to one of 1572 // its members. 1573 Owner->addDecl(Anon); 1574 1575 // Inject the members of the anonymous struct/union into the owning 1576 // context and into the identifier resolver chain for name lookup 1577 // purposes. 1578 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1579 Invalid = true; 1580 1581 // Mark this as an anonymous struct/union type. Note that we do not 1582 // do this until after we have already checked and injected the 1583 // members of this anonymous struct/union type, because otherwise 1584 // the members could be injected twice: once by DeclContext when it 1585 // builds its lookup table, and once by 1586 // InjectAnonymousStructOrUnionMembers. 1587 Record->setAnonymousStructOrUnion(true); 1588 1589 if (Invalid) 1590 Anon->setInvalidDecl(); 1591 1592 return DeclPtrTy::make(Anon); 1593} 1594 1595 1596/// GetNameForDeclarator - Determine the full declaration name for the 1597/// given Declarator. 1598DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1599 switch (D.getKind()) { 1600 case Declarator::DK_Abstract: 1601 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1602 return DeclarationName(); 1603 1604 case Declarator::DK_Normal: 1605 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1606 return DeclarationName(D.getIdentifier()); 1607 1608 case Declarator::DK_Constructor: { 1609 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1610 return Context.DeclarationNames.getCXXConstructorName( 1611 Context.getCanonicalType(Ty)); 1612 } 1613 1614 case Declarator::DK_Destructor: { 1615 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1616 return Context.DeclarationNames.getCXXDestructorName( 1617 Context.getCanonicalType(Ty)); 1618 } 1619 1620 case Declarator::DK_Conversion: { 1621 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1622 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1623 return Context.DeclarationNames.getCXXConversionFunctionName( 1624 Context.getCanonicalType(Ty)); 1625 } 1626 1627 case Declarator::DK_Operator: 1628 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1629 return Context.DeclarationNames.getCXXOperatorName( 1630 D.getOverloadedOperator()); 1631 1632 case Declarator::DK_TemplateId: { 1633 TemplateName Name 1634 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1635 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1636 return Template->getDeclName(); 1637 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1638 return Ovl->getDeclName(); 1639 1640 return DeclarationName(); 1641 } 1642 } 1643 1644 assert(false && "Unknown name kind"); 1645 return DeclarationName(); 1646} 1647 1648/// isNearlyMatchingFunction - Determine whether the C++ functions 1649/// Declaration and Definition are "nearly" matching. This heuristic 1650/// is used to improve diagnostics in the case where an out-of-line 1651/// function definition doesn't match any declaration within 1652/// the class or namespace. 1653static bool isNearlyMatchingFunction(ASTContext &Context, 1654 FunctionDecl *Declaration, 1655 FunctionDecl *Definition) { 1656 if (Declaration->param_size() != Definition->param_size()) 1657 return false; 1658 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1659 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1660 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1661 1662 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1663 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1664 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1665 return false; 1666 } 1667 1668 return true; 1669} 1670 1671Sema::DeclPtrTy 1672Sema::HandleDeclarator(Scope *S, Declarator &D, 1673 MultiTemplateParamsArg TemplateParamLists, 1674 bool IsFunctionDefinition) { 1675 DeclarationName Name = GetNameForDeclarator(D); 1676 1677 // All of these full declarators require an identifier. If it doesn't have 1678 // one, the ParsedFreeStandingDeclSpec action should be used. 1679 if (!Name) { 1680 if (!D.isInvalidType()) // Reject this if we think it is valid. 1681 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1682 diag::err_declarator_need_ident) 1683 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1684 return DeclPtrTy(); 1685 } 1686 1687 // The scope passed in may not be a decl scope. Zip up the scope tree until 1688 // we find one that is. 1689 while ((S->getFlags() & Scope::DeclScope) == 0 || 1690 (S->getFlags() & Scope::TemplateParamScope) != 0) 1691 S = S->getParent(); 1692 1693 // If this is an out-of-line definition of a member of a class template 1694 // or class template partial specialization, we may need to rebuild the 1695 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1696 // for more information. 1697 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1698 // handle expressions properly. 1699 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1700 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1701 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1702 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1703 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1704 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1705 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1706 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1707 // FIXME: Preserve type source info. 1708 QualType T = GetTypeFromParser(DS.getTypeRep()); 1709 EnterDeclaratorContext(S, DC); 1710 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1711 ExitDeclaratorContext(S); 1712 if (T.isNull()) 1713 return DeclPtrTy(); 1714 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1715 } 1716 } 1717 1718 DeclContext *DC; 1719 NamedDecl *PrevDecl; 1720 NamedDecl *New; 1721 1722 DeclaratorInfo *DInfo = 0; 1723 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1724 1725 // See if this is a redefinition of a variable in the same scope. 1726 if (D.getCXXScopeSpec().isInvalid()) { 1727 DC = CurContext; 1728 PrevDecl = 0; 1729 D.setInvalidType(); 1730 } else if (!D.getCXXScopeSpec().isSet()) { 1731 LookupNameKind NameKind = LookupOrdinaryName; 1732 1733 // If the declaration we're planning to build will be a function 1734 // or object with linkage, then look for another declaration with 1735 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1736 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1737 /* Do nothing*/; 1738 else if (R->isFunctionType()) { 1739 if (CurContext->isFunctionOrMethod() || 1740 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1741 NameKind = LookupRedeclarationWithLinkage; 1742 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1743 NameKind = LookupRedeclarationWithLinkage; 1744 else if (CurContext->getLookupContext()->isTranslationUnit() && 1745 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1746 NameKind = LookupRedeclarationWithLinkage; 1747 1748 DC = CurContext; 1749 LookupResult R; 1750 LookupName(R, S, Name, NameKind, true, 1751 NameKind == LookupRedeclarationWithLinkage, 1752 D.getIdentifierLoc()); 1753 PrevDecl = R.getAsSingleDecl(Context); 1754 } else { // Something like "int foo::x;" 1755 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1756 1757 if (!DC) { 1758 // If we could not compute the declaration context, it's because the 1759 // declaration context is dependent but does not refer to a class, 1760 // class template, or class template partial specialization. Complain 1761 // and return early, to avoid the coming semantic disaster. 1762 Diag(D.getIdentifierLoc(), 1763 diag::err_template_qualified_declarator_no_match) 1764 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1765 << D.getCXXScopeSpec().getRange(); 1766 return DeclPtrTy(); 1767 } 1768 1769 if (!DC->isDependentContext() && 1770 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1771 return DeclPtrTy(); 1772 1773 LookupResult Res; 1774 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1775 PrevDecl = Res.getAsSingleDecl(Context); 1776 1777 // C++ 7.3.1.2p2: 1778 // Members (including explicit specializations of templates) of a named 1779 // namespace can also be defined outside that namespace by explicit 1780 // qualification of the name being defined, provided that the entity being 1781 // defined was already declared in the namespace and the definition appears 1782 // after the point of declaration in a namespace that encloses the 1783 // declarations namespace. 1784 // 1785 // Note that we only check the context at this point. We don't yet 1786 // have enough information to make sure that PrevDecl is actually 1787 // the declaration we want to match. For example, given: 1788 // 1789 // class X { 1790 // void f(); 1791 // void f(float); 1792 // }; 1793 // 1794 // void X::f(int) { } // ill-formed 1795 // 1796 // In this case, PrevDecl will point to the overload set 1797 // containing the two f's declared in X, but neither of them 1798 // matches. 1799 1800 // First check whether we named the global scope. 1801 if (isa<TranslationUnitDecl>(DC)) { 1802 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1803 << Name << D.getCXXScopeSpec().getRange(); 1804 } else if (!CurContext->Encloses(DC)) { 1805 // The qualifying scope doesn't enclose the original declaration. 1806 // Emit diagnostic based on current scope. 1807 SourceLocation L = D.getIdentifierLoc(); 1808 SourceRange R = D.getCXXScopeSpec().getRange(); 1809 if (isa<FunctionDecl>(CurContext)) 1810 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1811 else 1812 Diag(L, diag::err_invalid_declarator_scope) 1813 << Name << cast<NamedDecl>(DC) << R; 1814 D.setInvalidType(); 1815 } 1816 } 1817 1818 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1819 // Maybe we will complain about the shadowed template parameter. 1820 if (!D.isInvalidType()) 1821 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1822 D.setInvalidType(); 1823 1824 // Just pretend that we didn't see the previous declaration. 1825 PrevDecl = 0; 1826 } 1827 1828 // In C++, the previous declaration we find might be a tag type 1829 // (class or enum). In this case, the new declaration will hide the 1830 // tag type. Note that this does does not apply if we're declaring a 1831 // typedef (C++ [dcl.typedef]p4). 1832 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1833 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1834 PrevDecl = 0; 1835 1836 bool Redeclaration = false; 1837 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1838 if (TemplateParamLists.size()) { 1839 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1840 return DeclPtrTy(); 1841 } 1842 1843 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1844 } else if (R->isFunctionType()) { 1845 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1846 move(TemplateParamLists), 1847 IsFunctionDefinition, Redeclaration); 1848 } else { 1849 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1850 move(TemplateParamLists), 1851 Redeclaration); 1852 } 1853 1854 if (New == 0) 1855 return DeclPtrTy(); 1856 1857 // If this has an identifier and is not an invalid redeclaration or 1858 // function template specialization, add it to the scope stack. 1859 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1860 !(isa<FunctionDecl>(New) && 1861 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1862 PushOnScopeChains(New, S); 1863 1864 return DeclPtrTy::make(New); 1865} 1866 1867/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1868/// types into constant array types in certain situations which would otherwise 1869/// be errors (for GCC compatibility). 1870static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1871 ASTContext &Context, 1872 bool &SizeIsNegative) { 1873 // This method tries to turn a variable array into a constant 1874 // array even when the size isn't an ICE. This is necessary 1875 // for compatibility with code that depends on gcc's buggy 1876 // constant expression folding, like struct {char x[(int)(char*)2];} 1877 SizeIsNegative = false; 1878 1879 QualifierCollector Qs; 1880 const Type *Ty = Qs.strip(T); 1881 1882 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1883 QualType Pointee = PTy->getPointeeType(); 1884 QualType FixedType = 1885 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1886 if (FixedType.isNull()) return FixedType; 1887 FixedType = Context.getPointerType(FixedType); 1888 return Qs.apply(FixedType); 1889 } 1890 1891 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1892 if (!VLATy) 1893 return QualType(); 1894 // FIXME: We should probably handle this case 1895 if (VLATy->getElementType()->isVariablyModifiedType()) 1896 return QualType(); 1897 1898 Expr::EvalResult EvalResult; 1899 if (!VLATy->getSizeExpr() || 1900 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1901 !EvalResult.Val.isInt()) 1902 return QualType(); 1903 1904 llvm::APSInt &Res = EvalResult.Val.getInt(); 1905 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1906 // TODO: preserve the size expression in declarator info 1907 return Context.getConstantArrayType(VLATy->getElementType(), 1908 Res, ArrayType::Normal, 0); 1909 } 1910 1911 SizeIsNegative = true; 1912 return QualType(); 1913} 1914 1915/// \brief Register the given locally-scoped external C declaration so 1916/// that it can be found later for redeclarations 1917void 1918Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1919 Scope *S) { 1920 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1921 "Decl is not a locally-scoped decl!"); 1922 // Note that we have a locally-scoped external with this name. 1923 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1924 1925 if (!PrevDecl) 1926 return; 1927 1928 // If there was a previous declaration of this variable, it may be 1929 // in our identifier chain. Update the identifier chain with the new 1930 // declaration. 1931 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1932 // The previous declaration was found on the identifer resolver 1933 // chain, so remove it from its scope. 1934 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1935 S = S->getParent(); 1936 1937 if (S) 1938 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1939 } 1940} 1941 1942/// \brief Diagnose function specifiers on a declaration of an identifier that 1943/// does not identify a function. 1944void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1945 // FIXME: We should probably indicate the identifier in question to avoid 1946 // confusion for constructs like "inline int a(), b;" 1947 if (D.getDeclSpec().isInlineSpecified()) 1948 Diag(D.getDeclSpec().getInlineSpecLoc(), 1949 diag::err_inline_non_function); 1950 1951 if (D.getDeclSpec().isVirtualSpecified()) 1952 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1953 diag::err_virtual_non_function); 1954 1955 if (D.getDeclSpec().isExplicitSpecified()) 1956 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1957 diag::err_explicit_non_function); 1958} 1959 1960NamedDecl* 1961Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1962 QualType R, DeclaratorInfo *DInfo, 1963 NamedDecl* PrevDecl, bool &Redeclaration) { 1964 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1965 if (D.getCXXScopeSpec().isSet()) { 1966 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1967 << D.getCXXScopeSpec().getRange(); 1968 D.setInvalidType(); 1969 // Pretend we didn't see the scope specifier. 1970 DC = 0; 1971 } 1972 1973 if (getLangOptions().CPlusPlus) { 1974 // Check that there are no default arguments (C++ only). 1975 CheckExtraCXXDefaultArguments(D); 1976 } 1977 1978 DiagnoseFunctionSpecifiers(D); 1979 1980 if (D.getDeclSpec().isThreadSpecified()) 1981 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1982 1983 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 1984 if (!NewTD) return 0; 1985 1986 // Handle attributes prior to checking for duplicates in MergeVarDecl 1987 ProcessDeclAttributes(S, NewTD, D); 1988 // Merge the decl with the existing one if appropriate. If the decl is 1989 // in an outer scope, it isn't the same thing. 1990 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1991 Redeclaration = true; 1992 MergeTypeDefDecl(NewTD, PrevDecl); 1993 } 1994 1995 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1996 // then it shall have block scope. 1997 QualType T = NewTD->getUnderlyingType(); 1998 if (T->isVariablyModifiedType()) { 1999 CurFunctionNeedsScopeChecking = true; 2000 2001 if (S->getFnParent() == 0) { 2002 bool SizeIsNegative; 2003 QualType FixedTy = 2004 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2005 if (!FixedTy.isNull()) { 2006 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2007 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2008 } else { 2009 if (SizeIsNegative) 2010 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2011 else if (T->isVariableArrayType()) 2012 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2013 else 2014 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2015 NewTD->setInvalidDecl(); 2016 } 2017 } 2018 } 2019 2020 // If this is the C FILE type, notify the AST context. 2021 if (IdentifierInfo *II = NewTD->getIdentifier()) 2022 if (!NewTD->isInvalidDecl() && 2023 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2024 if (II->isStr("FILE")) 2025 Context.setFILEDecl(NewTD); 2026 else if (II->isStr("jmp_buf")) 2027 Context.setjmp_bufDecl(NewTD); 2028 else if (II->isStr("sigjmp_buf")) 2029 Context.setsigjmp_bufDecl(NewTD); 2030 } 2031 2032 return NewTD; 2033} 2034 2035/// \brief Determines whether the given declaration is an out-of-scope 2036/// previous declaration. 2037/// 2038/// This routine should be invoked when name lookup has found a 2039/// previous declaration (PrevDecl) that is not in the scope where a 2040/// new declaration by the same name is being introduced. If the new 2041/// declaration occurs in a local scope, previous declarations with 2042/// linkage may still be considered previous declarations (C99 2043/// 6.2.2p4-5, C++ [basic.link]p6). 2044/// 2045/// \param PrevDecl the previous declaration found by name 2046/// lookup 2047/// 2048/// \param DC the context in which the new declaration is being 2049/// declared. 2050/// 2051/// \returns true if PrevDecl is an out-of-scope previous declaration 2052/// for a new delcaration with the same name. 2053static bool 2054isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2055 ASTContext &Context) { 2056 if (!PrevDecl) 2057 return 0; 2058 2059 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2060 // case we need to check each of the overloaded functions. 2061 if (!PrevDecl->hasLinkage()) 2062 return false; 2063 2064 if (Context.getLangOptions().CPlusPlus) { 2065 // C++ [basic.link]p6: 2066 // If there is a visible declaration of an entity with linkage 2067 // having the same name and type, ignoring entities declared 2068 // outside the innermost enclosing namespace scope, the block 2069 // scope declaration declares that same entity and receives the 2070 // linkage of the previous declaration. 2071 DeclContext *OuterContext = DC->getLookupContext(); 2072 if (!OuterContext->isFunctionOrMethod()) 2073 // This rule only applies to block-scope declarations. 2074 return false; 2075 else { 2076 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2077 if (PrevOuterContext->isRecord()) 2078 // We found a member function: ignore it. 2079 return false; 2080 else { 2081 // Find the innermost enclosing namespace for the new and 2082 // previous declarations. 2083 while (!OuterContext->isFileContext()) 2084 OuterContext = OuterContext->getParent(); 2085 while (!PrevOuterContext->isFileContext()) 2086 PrevOuterContext = PrevOuterContext->getParent(); 2087 2088 // The previous declaration is in a different namespace, so it 2089 // isn't the same function. 2090 if (OuterContext->getPrimaryContext() != 2091 PrevOuterContext->getPrimaryContext()) 2092 return false; 2093 } 2094 } 2095 } 2096 2097 return true; 2098} 2099 2100NamedDecl* 2101Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2102 QualType R, DeclaratorInfo *DInfo, 2103 NamedDecl* PrevDecl, 2104 MultiTemplateParamsArg TemplateParamLists, 2105 bool &Redeclaration) { 2106 DeclarationName Name = GetNameForDeclarator(D); 2107 2108 // Check that there are no default arguments (C++ only). 2109 if (getLangOptions().CPlusPlus) 2110 CheckExtraCXXDefaultArguments(D); 2111 2112 VarDecl *NewVD; 2113 VarDecl::StorageClass SC; 2114 switch (D.getDeclSpec().getStorageClassSpec()) { 2115 default: assert(0 && "Unknown storage class!"); 2116 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2117 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2118 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2119 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2120 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2121 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2122 case DeclSpec::SCS_mutable: 2123 // mutable can only appear on non-static class members, so it's always 2124 // an error here 2125 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2126 D.setInvalidType(); 2127 SC = VarDecl::None; 2128 break; 2129 } 2130 2131 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2132 if (!II) { 2133 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2134 << Name.getAsString(); 2135 return 0; 2136 } 2137 2138 DiagnoseFunctionSpecifiers(D); 2139 2140 if (!DC->isRecord() && S->getFnParent() == 0) { 2141 // C99 6.9p2: The storage-class specifiers auto and register shall not 2142 // appear in the declaration specifiers in an external declaration. 2143 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2144 2145 // If this is a register variable with an asm label specified, then this 2146 // is a GNU extension. 2147 if (SC == VarDecl::Register && D.getAsmLabel()) 2148 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2149 else 2150 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2151 D.setInvalidType(); 2152 } 2153 } 2154 if (DC->isRecord() && !CurContext->isRecord()) { 2155 // This is an out-of-line definition of a static data member. 2156 if (SC == VarDecl::Static) { 2157 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2158 diag::err_static_out_of_line) 2159 << CodeModificationHint::CreateRemoval( 2160 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2161 } else if (SC == VarDecl::None) 2162 SC = VarDecl::Static; 2163 } 2164 if (SC == VarDecl::Static) { 2165 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2166 if (RD->isLocalClass()) 2167 Diag(D.getIdentifierLoc(), 2168 diag::err_static_data_member_not_allowed_in_local_class) 2169 << Name << RD->getDeclName(); 2170 } 2171 } 2172 2173 // Match up the template parameter lists with the scope specifier, then 2174 // determine whether we have a template or a template specialization. 2175 bool isExplicitSpecialization = false; 2176 if (TemplateParameterList *TemplateParams 2177 = MatchTemplateParametersToScopeSpecifier( 2178 D.getDeclSpec().getSourceRange().getBegin(), 2179 D.getCXXScopeSpec(), 2180 (TemplateParameterList**)TemplateParamLists.get(), 2181 TemplateParamLists.size(), 2182 isExplicitSpecialization)) { 2183 if (TemplateParams->size() > 0) { 2184 // There is no such thing as a variable template. 2185 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2186 << II 2187 << SourceRange(TemplateParams->getTemplateLoc(), 2188 TemplateParams->getRAngleLoc()); 2189 return 0; 2190 } else { 2191 // There is an extraneous 'template<>' for this variable. Complain 2192 // about it, but allow the declaration of the variable. 2193 Diag(TemplateParams->getTemplateLoc(), 2194 diag::err_template_variable_noparams) 2195 << II 2196 << SourceRange(TemplateParams->getTemplateLoc(), 2197 TemplateParams->getRAngleLoc()); 2198 2199 isExplicitSpecialization = true; 2200 } 2201 } 2202 2203 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2204 II, R, DInfo, SC); 2205 2206 if (D.isInvalidType()) 2207 NewVD->setInvalidDecl(); 2208 2209 if (D.getDeclSpec().isThreadSpecified()) { 2210 if (NewVD->hasLocalStorage()) 2211 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2212 else if (!Context.Target.isTLSSupported()) 2213 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2214 else 2215 NewVD->setThreadSpecified(true); 2216 } 2217 2218 // Set the lexical context. If the declarator has a C++ scope specifier, the 2219 // lexical context will be different from the semantic context. 2220 NewVD->setLexicalDeclContext(CurContext); 2221 2222 // Handle attributes prior to checking for duplicates in MergeVarDecl 2223 ProcessDeclAttributes(S, NewVD, D); 2224 2225 // Handle GNU asm-label extension (encoded as an attribute). 2226 if (Expr *E = (Expr*) D.getAsmLabel()) { 2227 // The parser guarantees this is a string. 2228 StringLiteral *SE = cast<StringLiteral>(E); 2229 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2230 SE->getByteLength()))); 2231 } 2232 2233 // If name lookup finds a previous declaration that is not in the 2234 // same scope as the new declaration, this may still be an 2235 // acceptable redeclaration. 2236 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2237 !(NewVD->hasLinkage() && 2238 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2239 PrevDecl = 0; 2240 2241 // Merge the decl with the existing one if appropriate. 2242 if (PrevDecl) { 2243 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2244 // The user tried to define a non-static data member 2245 // out-of-line (C++ [dcl.meaning]p1). 2246 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2247 << D.getCXXScopeSpec().getRange(); 2248 PrevDecl = 0; 2249 NewVD->setInvalidDecl(); 2250 } 2251 } else if (D.getCXXScopeSpec().isSet()) { 2252 // No previous declaration in the qualifying scope. 2253 Diag(D.getIdentifierLoc(), diag::err_no_member) 2254 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2255 << D.getCXXScopeSpec().getRange(); 2256 NewVD->setInvalidDecl(); 2257 } 2258 2259 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2260 2261 // This is an explicit specialization of a static data member. Check it. 2262 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2263 CheckMemberSpecialization(NewVD, PrevDecl)) 2264 NewVD->setInvalidDecl(); 2265 2266 // attributes declared post-definition are currently ignored 2267 if (PrevDecl) { 2268 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2269 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2270 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2271 Diag(Def->getLocation(), diag::note_previous_definition); 2272 } 2273 } 2274 2275 // If this is a locally-scoped extern C variable, update the map of 2276 // such variables. 2277 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2278 !NewVD->isInvalidDecl()) 2279 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2280 2281 return NewVD; 2282} 2283 2284/// \brief Perform semantic checking on a newly-created variable 2285/// declaration. 2286/// 2287/// This routine performs all of the type-checking required for a 2288/// variable declaration once it has been built. It is used both to 2289/// check variables after they have been parsed and their declarators 2290/// have been translated into a declaration, and to check variables 2291/// that have been instantiated from a template. 2292/// 2293/// Sets NewVD->isInvalidDecl() if an error was encountered. 2294void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2295 bool &Redeclaration) { 2296 // If the decl is already known invalid, don't check it. 2297 if (NewVD->isInvalidDecl()) 2298 return; 2299 2300 QualType T = NewVD->getType(); 2301 2302 if (T->isObjCInterfaceType()) { 2303 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2304 return NewVD->setInvalidDecl(); 2305 } 2306 2307 // The variable can not have an abstract class type. 2308 if (RequireNonAbstractType(NewVD->getLocation(), T, 2309 diag::err_abstract_type_in_decl, 2310 AbstractVariableType)) 2311 return NewVD->setInvalidDecl(); 2312 2313 // Emit an error if an address space was applied to decl with local storage. 2314 // This includes arrays of objects with address space qualifiers, but not 2315 // automatic variables that point to other address spaces. 2316 // ISO/IEC TR 18037 S5.1.2 2317 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2318 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2319 return NewVD->setInvalidDecl(); 2320 } 2321 2322 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2323 && !NewVD->hasAttr<BlocksAttr>()) 2324 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2325 2326 bool isVM = T->isVariablyModifiedType(); 2327 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2328 NewVD->hasAttr<BlocksAttr>()) 2329 CurFunctionNeedsScopeChecking = true; 2330 2331 if ((isVM && NewVD->hasLinkage()) || 2332 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2333 bool SizeIsNegative; 2334 QualType FixedTy = 2335 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2336 2337 if (FixedTy.isNull() && T->isVariableArrayType()) { 2338 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2339 // FIXME: This won't give the correct result for 2340 // int a[10][n]; 2341 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2342 2343 if (NewVD->isFileVarDecl()) 2344 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2345 << SizeRange; 2346 else if (NewVD->getStorageClass() == VarDecl::Static) 2347 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2348 << SizeRange; 2349 else 2350 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2351 << SizeRange; 2352 return NewVD->setInvalidDecl(); 2353 } 2354 2355 if (FixedTy.isNull()) { 2356 if (NewVD->isFileVarDecl()) 2357 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2358 else 2359 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2360 return NewVD->setInvalidDecl(); 2361 } 2362 2363 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2364 NewVD->setType(FixedTy); 2365 } 2366 2367 if (!PrevDecl && NewVD->isExternC()) { 2368 // Since we did not find anything by this name and we're declaring 2369 // an extern "C" variable, look for a non-visible extern "C" 2370 // declaration with the same name. 2371 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2372 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2373 if (Pos != LocallyScopedExternalDecls.end()) 2374 PrevDecl = Pos->second; 2375 } 2376 2377 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2378 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2379 << T; 2380 return NewVD->setInvalidDecl(); 2381 } 2382 2383 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2384 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2385 return NewVD->setInvalidDecl(); 2386 } 2387 2388 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2389 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2390 return NewVD->setInvalidDecl(); 2391 } 2392 2393 if (PrevDecl) { 2394 Redeclaration = true; 2395 MergeVarDecl(NewVD, PrevDecl); 2396 } 2397} 2398 2399static bool isUsingDecl(Decl *D) { 2400 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2401} 2402 2403/// \brief Data used with FindOverriddenMethod 2404struct FindOverriddenMethodData { 2405 Sema *S; 2406 CXXMethodDecl *Method; 2407}; 2408 2409/// \brief Member lookup function that determines whether a given C++ 2410/// method overrides a method in a base class, to be used with 2411/// CXXRecordDecl::lookupInBases(). 2412static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2413 CXXBasePath &Path, 2414 void *UserData) { 2415 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2416 2417 FindOverriddenMethodData *Data 2418 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2419 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2420 Path.Decls.first != Path.Decls.second; 2421 ++Path.Decls.first) { 2422 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2423 OverloadedFunctionDecl::function_iterator MatchedDecl; 2424 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2425 return true; 2426 } 2427 } 2428 2429 return false; 2430} 2431 2432NamedDecl* 2433Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2434 QualType R, DeclaratorInfo *DInfo, 2435 NamedDecl* PrevDecl, 2436 MultiTemplateParamsArg TemplateParamLists, 2437 bool IsFunctionDefinition, bool &Redeclaration) { 2438 assert(R.getTypePtr()->isFunctionType()); 2439 2440 DeclarationName Name = GetNameForDeclarator(D); 2441 FunctionDecl::StorageClass SC = FunctionDecl::None; 2442 switch (D.getDeclSpec().getStorageClassSpec()) { 2443 default: assert(0 && "Unknown storage class!"); 2444 case DeclSpec::SCS_auto: 2445 case DeclSpec::SCS_register: 2446 case DeclSpec::SCS_mutable: 2447 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2448 diag::err_typecheck_sclass_func); 2449 D.setInvalidType(); 2450 break; 2451 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2452 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2453 case DeclSpec::SCS_static: { 2454 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2455 // C99 6.7.1p5: 2456 // The declaration of an identifier for a function that has 2457 // block scope shall have no explicit storage-class specifier 2458 // other than extern 2459 // See also (C++ [dcl.stc]p4). 2460 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2461 diag::err_static_block_func); 2462 SC = FunctionDecl::None; 2463 } else 2464 SC = FunctionDecl::Static; 2465 break; 2466 } 2467 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2468 } 2469 2470 if (D.getDeclSpec().isThreadSpecified()) 2471 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2472 2473 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2474 bool isInline = D.getDeclSpec().isInlineSpecified(); 2475 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2476 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2477 2478 // Check that the return type is not an abstract class type. 2479 // For record types, this is done by the AbstractClassUsageDiagnoser once 2480 // the class has been completely parsed. 2481 if (!DC->isRecord() && 2482 RequireNonAbstractType(D.getIdentifierLoc(), 2483 R->getAs<FunctionType>()->getResultType(), 2484 diag::err_abstract_type_in_decl, 2485 AbstractReturnType)) 2486 D.setInvalidType(); 2487 2488 // Do not allow returning a objc interface by-value. 2489 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2490 Diag(D.getIdentifierLoc(), 2491 diag::err_object_cannot_be_passed_returned_by_value) << 0 2492 << R->getAs<FunctionType>()->getResultType(); 2493 D.setInvalidType(); 2494 } 2495 2496 bool isVirtualOkay = false; 2497 FunctionDecl *NewFD; 2498 2499 if (isFriend) { 2500 // DC is the namespace in which the function is being declared. 2501 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2502 "friend function being created in a non-namespace context"); 2503 2504 // C++ [class.friend]p5 2505 // A function can be defined in a friend declaration of a 2506 // class . . . . Such a function is implicitly inline. 2507 isInline |= IsFunctionDefinition; 2508 } 2509 2510 if (D.getKind() == Declarator::DK_Constructor) { 2511 // This is a C++ constructor declaration. 2512 assert(DC->isRecord() && 2513 "Constructors can only be declared in a member context"); 2514 2515 R = CheckConstructorDeclarator(D, R, SC); 2516 2517 // Create the new declaration 2518 NewFD = CXXConstructorDecl::Create(Context, 2519 cast<CXXRecordDecl>(DC), 2520 D.getIdentifierLoc(), Name, R, DInfo, 2521 isExplicit, isInline, 2522 /*isImplicitlyDeclared=*/false); 2523 } else if (D.getKind() == Declarator::DK_Destructor) { 2524 // This is a C++ destructor declaration. 2525 if (DC->isRecord()) { 2526 R = CheckDestructorDeclarator(D, SC); 2527 2528 NewFD = CXXDestructorDecl::Create(Context, 2529 cast<CXXRecordDecl>(DC), 2530 D.getIdentifierLoc(), Name, R, 2531 isInline, 2532 /*isImplicitlyDeclared=*/false); 2533 2534 isVirtualOkay = true; 2535 } else { 2536 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2537 2538 // Create a FunctionDecl to satisfy the function definition parsing 2539 // code path. 2540 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2541 Name, R, DInfo, SC, isInline, 2542 /*hasPrototype=*/true); 2543 D.setInvalidType(); 2544 } 2545 } else if (D.getKind() == Declarator::DK_Conversion) { 2546 if (!DC->isRecord()) { 2547 Diag(D.getIdentifierLoc(), 2548 diag::err_conv_function_not_member); 2549 return 0; 2550 } 2551 2552 CheckConversionDeclarator(D, R, SC); 2553 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2554 D.getIdentifierLoc(), Name, R, DInfo, 2555 isInline, isExplicit); 2556 2557 isVirtualOkay = true; 2558 } else if (DC->isRecord()) { 2559 // If the of the function is the same as the name of the record, then this 2560 // must be an invalid constructor that has a return type. 2561 // (The parser checks for a return type and makes the declarator a 2562 // constructor if it has no return type). 2563 // must have an invalid constructor that has a return type 2564 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2565 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2566 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2567 << SourceRange(D.getIdentifierLoc()); 2568 return 0; 2569 } 2570 2571 // This is a C++ method declaration. 2572 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2573 D.getIdentifierLoc(), Name, R, DInfo, 2574 (SC == FunctionDecl::Static), isInline); 2575 2576 isVirtualOkay = (SC != FunctionDecl::Static); 2577 } else { 2578 // Determine whether the function was written with a 2579 // prototype. This true when: 2580 // - we're in C++ (where every function has a prototype), 2581 // - there is a prototype in the declarator, or 2582 // - the type R of the function is some kind of typedef or other reference 2583 // to a type name (which eventually refers to a function type). 2584 bool HasPrototype = 2585 getLangOptions().CPlusPlus || 2586 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2587 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2588 2589 NewFD = FunctionDecl::Create(Context, DC, 2590 D.getIdentifierLoc(), 2591 Name, R, DInfo, SC, isInline, HasPrototype); 2592 } 2593 2594 if (D.isInvalidType()) 2595 NewFD->setInvalidDecl(); 2596 2597 // Set the lexical context. If the declarator has a C++ 2598 // scope specifier, or is the object of a friend declaration, the 2599 // lexical context will be different from the semantic context. 2600 NewFD->setLexicalDeclContext(CurContext); 2601 2602 // Match up the template parameter lists with the scope specifier, then 2603 // determine whether we have a template or a template specialization. 2604 FunctionTemplateDecl *FunctionTemplate = 0; 2605 bool isExplicitSpecialization = false; 2606 bool isFunctionTemplateSpecialization = false; 2607 if (TemplateParameterList *TemplateParams 2608 = MatchTemplateParametersToScopeSpecifier( 2609 D.getDeclSpec().getSourceRange().getBegin(), 2610 D.getCXXScopeSpec(), 2611 (TemplateParameterList**)TemplateParamLists.get(), 2612 TemplateParamLists.size(), 2613 isExplicitSpecialization)) { 2614 if (TemplateParams->size() > 0) { 2615 // This is a function template 2616 2617 // Check that we can declare a template here. 2618 if (CheckTemplateDeclScope(S, TemplateParams)) 2619 return 0; 2620 2621 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2622 NewFD->getLocation(), 2623 Name, TemplateParams, 2624 NewFD); 2625 FunctionTemplate->setLexicalDeclContext(CurContext); 2626 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2627 } else { 2628 // This is a function template specialization. 2629 isFunctionTemplateSpecialization = true; 2630 } 2631 2632 // FIXME: Free this memory properly. 2633 TemplateParamLists.release(); 2634 } 2635 2636 // C++ [dcl.fct.spec]p5: 2637 // The virtual specifier shall only be used in declarations of 2638 // nonstatic class member functions that appear within a 2639 // member-specification of a class declaration; see 10.3. 2640 // 2641 if (isVirtual && !NewFD->isInvalidDecl()) { 2642 if (!isVirtualOkay) { 2643 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2644 diag::err_virtual_non_function); 2645 } else if (!CurContext->isRecord()) { 2646 // 'virtual' was specified outside of the class. 2647 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2648 << CodeModificationHint::CreateRemoval( 2649 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2650 } else { 2651 // Okay: Add virtual to the method. 2652 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2653 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2654 CurClass->setAggregate(false); 2655 CurClass->setPOD(false); 2656 CurClass->setEmpty(false); 2657 CurClass->setPolymorphic(true); 2658 CurClass->setHasTrivialConstructor(false); 2659 CurClass->setHasTrivialCopyConstructor(false); 2660 CurClass->setHasTrivialCopyAssignment(false); 2661 } 2662 } 2663 2664 if (isFriend) { 2665 if (FunctionTemplate) { 2666 FunctionTemplate->setObjectOfFriendDecl( 2667 /* PreviouslyDeclared= */ PrevDecl != NULL); 2668 FunctionTemplate->setAccess(AS_public); 2669 } 2670 else 2671 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2672 2673 NewFD->setAccess(AS_public); 2674 } 2675 2676 2677 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2678 // Look for virtual methods in base classes that this method might override. 2679 CXXBasePaths Paths; 2680 FindOverriddenMethodData Data; 2681 Data.Method = NewMD; 2682 Data.S = this; 2683 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2684 Paths)) { 2685 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2686 E = Paths.found_decls_end(); I != E; ++I) { 2687 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2688 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2689 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2690 NewMD->addOverriddenMethod(OldMD); 2691 } 2692 } 2693 } 2694 } 2695 2696 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2697 !CurContext->isRecord()) { 2698 // C++ [class.static]p1: 2699 // A data or function member of a class may be declared static 2700 // in a class definition, in which case it is a static member of 2701 // the class. 2702 2703 // Complain about the 'static' specifier if it's on an out-of-line 2704 // member function definition. 2705 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2706 diag::err_static_out_of_line) 2707 << CodeModificationHint::CreateRemoval( 2708 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2709 } 2710 2711 // Handle GNU asm-label extension (encoded as an attribute). 2712 if (Expr *E = (Expr*) D.getAsmLabel()) { 2713 // The parser guarantees this is a string. 2714 StringLiteral *SE = cast<StringLiteral>(E); 2715 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2716 SE->getByteLength()))); 2717 } 2718 2719 // Copy the parameter declarations from the declarator D to the function 2720 // declaration NewFD, if they are available. First scavenge them into Params. 2721 llvm::SmallVector<ParmVarDecl*, 16> Params; 2722 if (D.getNumTypeObjects() > 0) { 2723 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2724 2725 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2726 // function that takes no arguments, not a function that takes a 2727 // single void argument. 2728 // We let through "const void" here because Sema::GetTypeForDeclarator 2729 // already checks for that case. 2730 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2731 FTI.ArgInfo[0].Param && 2732 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2733 // Empty arg list, don't push any params. 2734 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2735 2736 // In C++, the empty parameter-type-list must be spelled "void"; a 2737 // typedef of void is not permitted. 2738 if (getLangOptions().CPlusPlus && 2739 Param->getType().getUnqualifiedType() != Context.VoidTy) 2740 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2741 // FIXME: Leaks decl? 2742 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2743 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2744 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2745 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2746 Param->setDeclContext(NewFD); 2747 Params.push_back(Param); 2748 } 2749 } 2750 2751 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2752 // When we're declaring a function with a typedef, typeof, etc as in the 2753 // following example, we'll need to synthesize (unnamed) 2754 // parameters for use in the declaration. 2755 // 2756 // @code 2757 // typedef void fn(int); 2758 // fn f; 2759 // @endcode 2760 2761 // Synthesize a parameter for each argument type. 2762 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2763 AE = FT->arg_type_end(); AI != AE; ++AI) { 2764 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2765 SourceLocation(), 0, 2766 *AI, /*DInfo=*/0, 2767 VarDecl::None, 0); 2768 Param->setImplicit(); 2769 Params.push_back(Param); 2770 } 2771 } else { 2772 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2773 "Should not need args for typedef of non-prototype fn"); 2774 } 2775 // Finally, we know we have the right number of parameters, install them. 2776 NewFD->setParams(Context, Params.data(), Params.size()); 2777 2778 // If name lookup finds a previous declaration that is not in the 2779 // same scope as the new declaration, this may still be an 2780 // acceptable redeclaration. 2781 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2782 !(NewFD->hasLinkage() && 2783 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2784 PrevDecl = 0; 2785 2786 // If the declarator is a template-id, translate the parser's template 2787 // argument list into our AST format. 2788 bool HasExplicitTemplateArgs = false; 2789 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2790 SourceLocation LAngleLoc, RAngleLoc; 2791 if (D.getKind() == Declarator::DK_TemplateId) { 2792 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2793 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2794 TemplateId->getTemplateArgs(), 2795 TemplateId->getTemplateArgIsType(), 2796 TemplateId->NumArgs); 2797 translateTemplateArguments(TemplateArgsPtr, 2798 TemplateId->getTemplateArgLocations(), 2799 TemplateArgs); 2800 TemplateArgsPtr.release(); 2801 2802 HasExplicitTemplateArgs = true; 2803 LAngleLoc = TemplateId->LAngleLoc; 2804 RAngleLoc = TemplateId->RAngleLoc; 2805 2806 if (FunctionTemplate) { 2807 // FIXME: Diagnose function template with explicit template 2808 // arguments. 2809 HasExplicitTemplateArgs = false; 2810 } else if (!isFunctionTemplateSpecialization && 2811 !D.getDeclSpec().isFriendSpecified()) { 2812 // We have encountered something that the user meant to be a 2813 // specialization (because it has explicitly-specified template 2814 // arguments) but that was not introduced with a "template<>" (or had 2815 // too few of them). 2816 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2817 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2818 << CodeModificationHint::CreateInsertion( 2819 D.getDeclSpec().getSourceRange().getBegin(), 2820 "template<> "); 2821 isFunctionTemplateSpecialization = true; 2822 } 2823 } 2824 2825 if (isFunctionTemplateSpecialization) { 2826 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2827 LAngleLoc, TemplateArgs.data(), 2828 TemplateArgs.size(), RAngleLoc, 2829 PrevDecl)) 2830 NewFD->setInvalidDecl(); 2831 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2832 CheckMemberSpecialization(NewFD, PrevDecl)) 2833 NewFD->setInvalidDecl(); 2834 2835 // Perform semantic checking on the function declaration. 2836 bool OverloadableAttrRequired = false; // FIXME: HACK! 2837 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2838 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2839 2840 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2841 // An out-of-line member function declaration must also be a 2842 // definition (C++ [dcl.meaning]p1). 2843 // Note that this is not the case for explicit specializations of 2844 // function templates or member functions of class templates, per 2845 // C++ [temp.expl.spec]p2. 2846 if (!IsFunctionDefinition && !isFriend && 2847 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2848 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2849 << D.getCXXScopeSpec().getRange(); 2850 NewFD->setInvalidDecl(); 2851 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2852 // The user tried to provide an out-of-line definition for a 2853 // function that is a member of a class or namespace, but there 2854 // was no such member function declared (C++ [class.mfct]p2, 2855 // C++ [namespace.memdef]p2). For example: 2856 // 2857 // class X { 2858 // void f() const; 2859 // }; 2860 // 2861 // void X::f() { } // ill-formed 2862 // 2863 // Complain about this problem, and attempt to suggest close 2864 // matches (e.g., those that differ only in cv-qualifiers and 2865 // whether the parameter types are references). 2866 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2867 << Name << DC << D.getCXXScopeSpec().getRange(); 2868 NewFD->setInvalidDecl(); 2869 2870 LookupResult Prev; 2871 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2872 assert(!Prev.isAmbiguous() && 2873 "Cannot have an ambiguity in previous-declaration lookup"); 2874 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2875 Func != FuncEnd; ++Func) { 2876 if (isa<FunctionDecl>(*Func) && 2877 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2878 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2879 } 2880 2881 PrevDecl = 0; 2882 } 2883 } 2884 2885 // Handle attributes. We need to have merged decls when handling attributes 2886 // (for example to check for conflicts, etc). 2887 // FIXME: This needs to happen before we merge declarations. Then, 2888 // let attribute merging cope with attribute conflicts. 2889 ProcessDeclAttributes(S, NewFD, D); 2890 2891 // attributes declared post-definition are currently ignored 2892 if (Redeclaration && PrevDecl) { 2893 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2894 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2895 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2896 Diag(Def->getLocation(), diag::note_previous_definition); 2897 } 2898 } 2899 2900 AddKnownFunctionAttributes(NewFD); 2901 2902 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2903 // If a function name is overloadable in C, then every function 2904 // with that name must be marked "overloadable". 2905 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2906 << Redeclaration << NewFD; 2907 if (PrevDecl) 2908 Diag(PrevDecl->getLocation(), 2909 diag::note_attribute_overloadable_prev_overload); 2910 NewFD->addAttr(::new (Context) OverloadableAttr()); 2911 } 2912 2913 // If this is a locally-scoped extern C function, update the 2914 // map of such names. 2915 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2916 && !NewFD->isInvalidDecl()) 2917 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2918 2919 // Set this FunctionDecl's range up to the right paren. 2920 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2921 2922 if (FunctionTemplate && NewFD->isInvalidDecl()) 2923 FunctionTemplate->setInvalidDecl(); 2924 2925 if (FunctionTemplate) 2926 return FunctionTemplate; 2927 2928 return NewFD; 2929} 2930 2931/// \brief Perform semantic checking of a new function declaration. 2932/// 2933/// Performs semantic analysis of the new function declaration 2934/// NewFD. This routine performs all semantic checking that does not 2935/// require the actual declarator involved in the declaration, and is 2936/// used both for the declaration of functions as they are parsed 2937/// (called via ActOnDeclarator) and for the declaration of functions 2938/// that have been instantiated via C++ template instantiation (called 2939/// via InstantiateDecl). 2940/// 2941/// \param IsExplicitSpecialiation whether this new function declaration is 2942/// an explicit specialization of the previous declaration. 2943/// 2944/// This sets NewFD->isInvalidDecl() to true if there was an error. 2945void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2946 bool IsExplicitSpecialization, 2947 bool &Redeclaration, 2948 bool &OverloadableAttrRequired) { 2949 // If NewFD is already known erroneous, don't do any of this checking. 2950 if (NewFD->isInvalidDecl()) 2951 return; 2952 2953 if (NewFD->getResultType()->isVariablyModifiedType()) { 2954 // Functions returning a variably modified type violate C99 6.7.5.2p2 2955 // because all functions have linkage. 2956 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2957 return NewFD->setInvalidDecl(); 2958 } 2959 2960 if (NewFD->isMain()) 2961 CheckMain(NewFD); 2962 2963 // Check for a previous declaration of this name. 2964 if (!PrevDecl && NewFD->isExternC()) { 2965 // Since we did not find anything by this name and we're declaring 2966 // an extern "C" function, look for a non-visible extern "C" 2967 // declaration with the same name. 2968 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2969 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2970 if (Pos != LocallyScopedExternalDecls.end()) 2971 PrevDecl = Pos->second; 2972 } 2973 2974 // Merge or overload the declaration with an existing declaration of 2975 // the same name, if appropriate. 2976 if (PrevDecl) { 2977 // Determine whether NewFD is an overload of PrevDecl or 2978 // a declaration that requires merging. If it's an overload, 2979 // there's no more work to do here; we'll just add the new 2980 // function to the scope. 2981 OverloadedFunctionDecl::function_iterator MatchedDecl; 2982 2983 if (!getLangOptions().CPlusPlus && 2984 AllowOverloadingOfFunction(PrevDecl, Context)) { 2985 OverloadableAttrRequired = true; 2986 2987 // Functions marked "overloadable" must have a prototype (that 2988 // we can't get through declaration merging). 2989 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2990 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2991 << NewFD; 2992 Redeclaration = true; 2993 2994 // Turn this into a variadic function with no parameters. 2995 QualType R = Context.getFunctionType( 2996 NewFD->getType()->getAs<FunctionType>()->getResultType(), 2997 0, 0, true, 0); 2998 NewFD->setType(R); 2999 return NewFD->setInvalidDecl(); 3000 } 3001 } 3002 3003 if (PrevDecl && 3004 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3005 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3006 Redeclaration = true; 3007 Decl *OldDecl = PrevDecl; 3008 3009 // If PrevDecl was an overloaded function, extract the 3010 // FunctionDecl that matched. 3011 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3012 OldDecl = *MatchedDecl; 3013 3014 // NewFD and OldDecl represent declarations that need to be 3015 // merged. 3016 if (MergeFunctionDecl(NewFD, OldDecl)) 3017 return NewFD->setInvalidDecl(); 3018 3019 if (FunctionTemplateDecl *OldTemplateDecl 3020 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3021 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3022 FunctionTemplateDecl *NewTemplateDecl 3023 = NewFD->getDescribedFunctionTemplate(); 3024 assert(NewTemplateDecl && "Template/non-template mismatch"); 3025 if (CXXMethodDecl *Method 3026 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3027 Method->setAccess(OldTemplateDecl->getAccess()); 3028 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3029 } 3030 3031 // If this is an explicit specialization of a member that is a function 3032 // template, mark it as a member specialization. 3033 if (IsExplicitSpecialization && 3034 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3035 NewTemplateDecl->setMemberSpecialization(); 3036 assert(OldTemplateDecl->isMemberSpecialization()); 3037 } 3038 } else { 3039 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3040 NewFD->setAccess(OldDecl->getAccess()); 3041 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3042 } 3043 } 3044 } 3045 3046 // Semantic checking for this function declaration (in isolation). 3047 if (getLangOptions().CPlusPlus) { 3048 // C++-specific checks. 3049 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3050 CheckConstructor(Constructor); 3051 } else if (isa<CXXDestructorDecl>(NewFD)) { 3052 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3053 QualType ClassType = Context.getTypeDeclType(Record); 3054 if (!ClassType->isDependentType()) { 3055 DeclarationName Name 3056 = Context.DeclarationNames.getCXXDestructorName( 3057 Context.getCanonicalType(ClassType)); 3058 if (NewFD->getDeclName() != Name) { 3059 Diag(NewFD->getLocation(), diag::err_destructor_name); 3060 return NewFD->setInvalidDecl(); 3061 } 3062 } 3063 Record->setUserDeclaredDestructor(true); 3064 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3065 // user-defined destructor. 3066 Record->setPOD(false); 3067 3068 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3069 // declared destructor. 3070 // FIXME: C++0x: don't do this for "= default" destructors 3071 Record->setHasTrivialDestructor(false); 3072 } else if (CXXConversionDecl *Conversion 3073 = dyn_cast<CXXConversionDecl>(NewFD)) 3074 ActOnConversionDeclarator(Conversion); 3075 3076 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3077 if (NewFD->isOverloadedOperator() && 3078 CheckOverloadedOperatorDeclaration(NewFD)) 3079 return NewFD->setInvalidDecl(); 3080 3081 // In C++, check default arguments now that we have merged decls. Unless 3082 // the lexical context is the class, because in this case this is done 3083 // during delayed parsing anyway. 3084 if (!CurContext->isRecord()) 3085 CheckCXXDefaultArguments(NewFD); 3086 } 3087} 3088 3089void Sema::CheckMain(FunctionDecl* FD) { 3090 // C++ [basic.start.main]p3: A program that declares main to be inline 3091 // or static is ill-formed. 3092 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3093 // shall not appear in a declaration of main. 3094 // static main is not an error under C99, but we should warn about it. 3095 bool isInline = FD->isInline(); 3096 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3097 if (isInline || isStatic) { 3098 unsigned diagID = diag::warn_unusual_main_decl; 3099 if (isInline || getLangOptions().CPlusPlus) 3100 diagID = diag::err_unusual_main_decl; 3101 3102 int which = isStatic + (isInline << 1) - 1; 3103 Diag(FD->getLocation(), diagID) << which; 3104 } 3105 3106 QualType T = FD->getType(); 3107 assert(T->isFunctionType() && "function decl is not of function type"); 3108 const FunctionType* FT = T->getAs<FunctionType>(); 3109 3110 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3111 // TODO: add a replacement fixit to turn the return type into 'int'. 3112 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3113 FD->setInvalidDecl(true); 3114 } 3115 3116 // Treat protoless main() as nullary. 3117 if (isa<FunctionNoProtoType>(FT)) return; 3118 3119 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3120 unsigned nparams = FTP->getNumArgs(); 3121 assert(FD->getNumParams() == nparams); 3122 3123 if (nparams > 3) { 3124 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3125 FD->setInvalidDecl(true); 3126 nparams = 3; 3127 } 3128 3129 // FIXME: a lot of the following diagnostics would be improved 3130 // if we had some location information about types. 3131 3132 QualType CharPP = 3133 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3134 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3135 3136 for (unsigned i = 0; i < nparams; ++i) { 3137 QualType AT = FTP->getArgType(i); 3138 3139 bool mismatch = true; 3140 3141 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3142 mismatch = false; 3143 else if (Expected[i] == CharPP) { 3144 // As an extension, the following forms are okay: 3145 // char const ** 3146 // char const * const * 3147 // char * const * 3148 3149 QualifierCollector qs; 3150 const PointerType* PT; 3151 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3152 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3153 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3154 qs.removeConst(); 3155 mismatch = !qs.empty(); 3156 } 3157 } 3158 3159 if (mismatch) { 3160 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3161 // TODO: suggest replacing given type with expected type 3162 FD->setInvalidDecl(true); 3163 } 3164 } 3165 3166 if (nparams == 1 && !FD->isInvalidDecl()) { 3167 Diag(FD->getLocation(), diag::warn_main_one_arg); 3168 } 3169} 3170 3171bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3172 // FIXME: Need strict checking. In C89, we need to check for 3173 // any assignment, increment, decrement, function-calls, or 3174 // commas outside of a sizeof. In C99, it's the same list, 3175 // except that the aforementioned are allowed in unevaluated 3176 // expressions. Everything else falls under the 3177 // "may accept other forms of constant expressions" exception. 3178 // (We never end up here for C++, so the constant expression 3179 // rules there don't matter.) 3180 if (Init->isConstantInitializer(Context)) 3181 return false; 3182 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3183 << Init->getSourceRange(); 3184 return true; 3185} 3186 3187void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3188 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3189} 3190 3191/// AddInitializerToDecl - Adds the initializer Init to the 3192/// declaration dcl. If DirectInit is true, this is C++ direct 3193/// initialization rather than copy initialization. 3194void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3195 Decl *RealDecl = dcl.getAs<Decl>(); 3196 // If there is no declaration, there was an error parsing it. Just ignore 3197 // the initializer. 3198 if (RealDecl == 0) 3199 return; 3200 3201 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3202 // With declarators parsed the way they are, the parser cannot 3203 // distinguish between a normal initializer and a pure-specifier. 3204 // Thus this grotesque test. 3205 IntegerLiteral *IL; 3206 Expr *Init = static_cast<Expr *>(init.get()); 3207 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3208 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3209 if (Method->isVirtualAsWritten()) { 3210 Method->setPure(); 3211 3212 // A class is abstract if at least one function is pure virtual. 3213 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3214 } else if (!Method->isInvalidDecl()) { 3215 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3216 << Method->getDeclName() << Init->getSourceRange(); 3217 Method->setInvalidDecl(); 3218 } 3219 } else { 3220 Diag(Method->getLocation(), diag::err_member_function_initialization) 3221 << Method->getDeclName() << Init->getSourceRange(); 3222 Method->setInvalidDecl(); 3223 } 3224 return; 3225 } 3226 3227 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3228 if (!VDecl) { 3229 if (getLangOptions().CPlusPlus && 3230 RealDecl->getLexicalDeclContext()->isRecord() && 3231 isa<NamedDecl>(RealDecl)) 3232 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3233 << cast<NamedDecl>(RealDecl)->getDeclName(); 3234 else 3235 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3236 RealDecl->setInvalidDecl(); 3237 return; 3238 } 3239 3240 if (!VDecl->getType()->isArrayType() && 3241 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3242 diag::err_typecheck_decl_incomplete_type)) { 3243 RealDecl->setInvalidDecl(); 3244 return; 3245 } 3246 3247 const VarDecl *Def = 0; 3248 if (VDecl->getDefinition(Def)) { 3249 Diag(VDecl->getLocation(), diag::err_redefinition) 3250 << VDecl->getDeclName(); 3251 Diag(Def->getLocation(), diag::note_previous_definition); 3252 VDecl->setInvalidDecl(); 3253 return; 3254 } 3255 3256 // Take ownership of the expression, now that we're sure we have somewhere 3257 // to put it. 3258 Expr *Init = init.takeAs<Expr>(); 3259 assert(Init && "missing initializer"); 3260 3261 // Get the decls type and save a reference for later, since 3262 // CheckInitializerTypes may change it. 3263 QualType DclT = VDecl->getType(), SavT = DclT; 3264 if (VDecl->isBlockVarDecl()) { 3265 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3266 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3267 VDecl->setInvalidDecl(); 3268 } else if (!VDecl->isInvalidDecl()) { 3269 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3270 VDecl->getDeclName(), DirectInit)) 3271 VDecl->setInvalidDecl(); 3272 3273 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3274 // Don't check invalid declarations to avoid emitting useless diagnostics. 3275 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3276 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3277 CheckForConstantInitializer(Init, DclT); 3278 } 3279 } 3280 } else if (VDecl->isStaticDataMember() && 3281 VDecl->getLexicalDeclContext()->isRecord()) { 3282 // This is an in-class initialization for a static data member, e.g., 3283 // 3284 // struct S { 3285 // static const int value = 17; 3286 // }; 3287 3288 // Attach the initializer 3289 VDecl->setInit(Context, Init); 3290 3291 // C++ [class.mem]p4: 3292 // A member-declarator can contain a constant-initializer only 3293 // if it declares a static member (9.4) of const integral or 3294 // const enumeration type, see 9.4.2. 3295 QualType T = VDecl->getType(); 3296 if (!T->isDependentType() && 3297 (!Context.getCanonicalType(T).isConstQualified() || 3298 !T->isIntegralType())) { 3299 Diag(VDecl->getLocation(), diag::err_member_initialization) 3300 << VDecl->getDeclName() << Init->getSourceRange(); 3301 VDecl->setInvalidDecl(); 3302 } else { 3303 // C++ [class.static.data]p4: 3304 // If a static data member is of const integral or const 3305 // enumeration type, its declaration in the class definition 3306 // can specify a constant-initializer which shall be an 3307 // integral constant expression (5.19). 3308 if (!Init->isTypeDependent() && 3309 !Init->getType()->isIntegralType()) { 3310 // We have a non-dependent, non-integral or enumeration type. 3311 Diag(Init->getSourceRange().getBegin(), 3312 diag::err_in_class_initializer_non_integral_type) 3313 << Init->getType() << Init->getSourceRange(); 3314 VDecl->setInvalidDecl(); 3315 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3316 // Check whether the expression is a constant expression. 3317 llvm::APSInt Value; 3318 SourceLocation Loc; 3319 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3320 Diag(Loc, diag::err_in_class_initializer_non_constant) 3321 << Init->getSourceRange(); 3322 VDecl->setInvalidDecl(); 3323 } else if (!VDecl->getType()->isDependentType()) 3324 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3325 } 3326 } 3327 } else if (VDecl->isFileVarDecl()) { 3328 if (VDecl->getStorageClass() == VarDecl::Extern) 3329 Diag(VDecl->getLocation(), diag::warn_extern_init); 3330 if (!VDecl->isInvalidDecl()) 3331 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3332 VDecl->getDeclName(), DirectInit)) 3333 VDecl->setInvalidDecl(); 3334 3335 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3336 // Don't check invalid declarations to avoid emitting useless diagnostics. 3337 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3338 // C99 6.7.8p4. All file scoped initializers need to be constant. 3339 CheckForConstantInitializer(Init, DclT); 3340 } 3341 } 3342 // If the type changed, it means we had an incomplete type that was 3343 // completed by the initializer. For example: 3344 // int ary[] = { 1, 3, 5 }; 3345 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3346 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3347 VDecl->setType(DclT); 3348 Init->setType(DclT); 3349 } 3350 3351 Init = MaybeCreateCXXExprWithTemporaries(Init, 3352 /*ShouldDestroyTemporaries=*/true); 3353 // Attach the initializer to the decl. 3354 VDecl->setInit(Context, Init); 3355 3356 // If the previous declaration of VDecl was a tentative definition, 3357 // remove it from the set of tentative definitions. 3358 if (VDecl->getPreviousDeclaration() && 3359 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3360 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3361 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3362 } 3363 3364 return; 3365} 3366 3367void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3368 bool TypeContainsUndeducedAuto) { 3369 Decl *RealDecl = dcl.getAs<Decl>(); 3370 3371 // If there is no declaration, there was an error parsing it. Just ignore it. 3372 if (RealDecl == 0) 3373 return; 3374 3375 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3376 QualType Type = Var->getType(); 3377 3378 // Record tentative definitions. 3379 if (Var->isTentativeDefinition(Context)) { 3380 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3381 InsertPair = 3382 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3383 3384 // Keep the latest definition in the map. If we see 'int i; int i;' we 3385 // want the second one in the map. 3386 InsertPair.first->second = Var; 3387 3388 // However, for the list, we don't care about the order, just make sure 3389 // that there are no dupes for a given declaration name. 3390 if (InsertPair.second) 3391 TentativeDefinitionList.push_back(Var->getDeclName()); 3392 } 3393 3394 // C++ [dcl.init.ref]p3: 3395 // The initializer can be omitted for a reference only in a 3396 // parameter declaration (8.3.5), in the declaration of a 3397 // function return type, in the declaration of a class member 3398 // within its class declaration (9.2), and where the extern 3399 // specifier is explicitly used. 3400 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3401 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3402 << Var->getDeclName() 3403 << SourceRange(Var->getLocation(), Var->getLocation()); 3404 Var->setInvalidDecl(); 3405 return; 3406 } 3407 3408 // C++0x [dcl.spec.auto]p3 3409 if (TypeContainsUndeducedAuto) { 3410 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3411 << Var->getDeclName() << Type; 3412 Var->setInvalidDecl(); 3413 return; 3414 } 3415 3416 // C++ [temp.expl.spec]p15: 3417 // An explicit specialization of a static data member of a template is a 3418 // definition if the declaration includes an initializer; otherwise, it 3419 // is a declaration. 3420 if (Var->isStaticDataMember() && 3421 Var->getInstantiatedFromStaticDataMember() && 3422 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3423 return; 3424 3425 // C++ [dcl.init]p9: 3426 // If no initializer is specified for an object, and the object 3427 // is of (possibly cv-qualified) non-POD class type (or array 3428 // thereof), the object shall be default-initialized; if the 3429 // object is of const-qualified type, the underlying class type 3430 // shall have a user-declared default constructor. 3431 // 3432 // FIXME: Diagnose the "user-declared default constructor" bit. 3433 if (getLangOptions().CPlusPlus) { 3434 QualType InitType = Type; 3435 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3436 InitType = Array->getElementType(); 3437 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3438 InitType->isRecordType() && !InitType->isDependentType()) { 3439 if (!RequireCompleteType(Var->getLocation(), InitType, 3440 diag::err_invalid_incomplete_type_use)) { 3441 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3442 3443 CXXConstructorDecl *Constructor 3444 = PerformInitializationByConstructor(InitType, 3445 MultiExprArg(*this, 0, 0), 3446 Var->getLocation(), 3447 SourceRange(Var->getLocation(), 3448 Var->getLocation()), 3449 Var->getDeclName(), 3450 IK_Default, 3451 ConstructorArgs); 3452 3453 // FIXME: Location info for the variable initialization? 3454 if (!Constructor) 3455 Var->setInvalidDecl(); 3456 else { 3457 // FIXME: Cope with initialization of arrays 3458 if (!Constructor->isTrivial() && 3459 InitializeVarWithConstructor(Var, Constructor, InitType, 3460 move_arg(ConstructorArgs))) 3461 Var->setInvalidDecl(); 3462 3463 FinalizeVarWithDestructor(Var, InitType); 3464 } 3465 } else { 3466 Var->setInvalidDecl(); 3467 } 3468 } 3469 } 3470 3471#if 0 3472 // FIXME: Temporarily disabled because we are not properly parsing 3473 // linkage specifications on declarations, e.g., 3474 // 3475 // extern "C" const CGPoint CGPointerZero; 3476 // 3477 // C++ [dcl.init]p9: 3478 // 3479 // If no initializer is specified for an object, and the 3480 // object is of (possibly cv-qualified) non-POD class type (or 3481 // array thereof), the object shall be default-initialized; if 3482 // the object is of const-qualified type, the underlying class 3483 // type shall have a user-declared default 3484 // constructor. Otherwise, if no initializer is specified for 3485 // an object, the object and its subobjects, if any, have an 3486 // indeterminate initial value; if the object or any of its 3487 // subobjects are of const-qualified type, the program is 3488 // ill-formed. 3489 // 3490 // This isn't technically an error in C, so we don't diagnose it. 3491 // 3492 // FIXME: Actually perform the POD/user-defined default 3493 // constructor check. 3494 if (getLangOptions().CPlusPlus && 3495 Context.getCanonicalType(Type).isConstQualified() && 3496 !Var->hasExternalStorage()) 3497 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3498 << Var->getName() 3499 << SourceRange(Var->getLocation(), Var->getLocation()); 3500#endif 3501 } 3502} 3503 3504Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3505 DeclPtrTy *Group, 3506 unsigned NumDecls) { 3507 llvm::SmallVector<Decl*, 8> Decls; 3508 3509 if (DS.isTypeSpecOwned()) 3510 Decls.push_back((Decl*)DS.getTypeRep()); 3511 3512 for (unsigned i = 0; i != NumDecls; ++i) 3513 if (Decl *D = Group[i].getAs<Decl>()) 3514 Decls.push_back(D); 3515 3516 // Perform semantic analysis that depends on having fully processed both 3517 // the declarator and initializer. 3518 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3519 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3520 if (!IDecl) 3521 continue; 3522 QualType T = IDecl->getType(); 3523 3524 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3525 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3526 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3527 if (T->isDependentType()) { 3528 // If T is dependent, we should not require a complete type. 3529 // (RequireCompleteType shouldn't be called with dependent types.) 3530 // But we still can at least check if we've got an array of unspecified 3531 // size without an initializer. 3532 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3533 !IDecl->getInit()) { 3534 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3535 << T; 3536 IDecl->setInvalidDecl(); 3537 } 3538 } else if (!IDecl->isInvalidDecl()) { 3539 // If T is an incomplete array type with an initializer list that is 3540 // dependent on something, its size has not been fixed. We could attempt 3541 // to fix the size for such arrays, but we would still have to check 3542 // here for initializers containing a C++0x vararg expansion, e.g. 3543 // template <typename... Args> void f(Args... args) { 3544 // int vals[] = { args }; 3545 // } 3546 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3547 Expr *Init = IDecl->getInit(); 3548 if (IAT && Init && 3549 (Init->isTypeDependent() || Init->isValueDependent())) { 3550 // Check that the member type of the array is complete, at least. 3551 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3552 diag::err_typecheck_decl_incomplete_type)) 3553 IDecl->setInvalidDecl(); 3554 } else if (RequireCompleteType(IDecl->getLocation(), T, 3555 diag::err_typecheck_decl_incomplete_type)) 3556 IDecl->setInvalidDecl(); 3557 } 3558 } 3559 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3560 // object that has file scope without an initializer, and without a 3561 // storage-class specifier or with the storage-class specifier "static", 3562 // constitutes a tentative definition. Note: A tentative definition with 3563 // external linkage is valid (C99 6.2.2p5). 3564 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3565 if (const IncompleteArrayType *ArrayT 3566 = Context.getAsIncompleteArrayType(T)) { 3567 if (RequireCompleteType(IDecl->getLocation(), 3568 ArrayT->getElementType(), 3569 diag::err_illegal_decl_array_incomplete_type)) 3570 IDecl->setInvalidDecl(); 3571 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3572 // C99 6.9.2p3: If the declaration of an identifier for an object is 3573 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3574 // declared type shall not be an incomplete type. 3575 // NOTE: code such as the following 3576 // static struct s; 3577 // struct s { int a; }; 3578 // is accepted by gcc. Hence here we issue a warning instead of 3579 // an error and we do not invalidate the static declaration. 3580 // NOTE: to avoid multiple warnings, only check the first declaration. 3581 if (IDecl->getPreviousDeclaration() == 0) 3582 RequireCompleteType(IDecl->getLocation(), T, 3583 diag::ext_typecheck_decl_incomplete_type); 3584 } 3585 } 3586 } 3587 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3588 Decls.data(), Decls.size())); 3589} 3590 3591 3592/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3593/// to introduce parameters into function prototype scope. 3594Sema::DeclPtrTy 3595Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3596 const DeclSpec &DS = D.getDeclSpec(); 3597 3598 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3599 VarDecl::StorageClass StorageClass = VarDecl::None; 3600 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3601 StorageClass = VarDecl::Register; 3602 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3603 Diag(DS.getStorageClassSpecLoc(), 3604 diag::err_invalid_storage_class_in_func_decl); 3605 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3606 } 3607 3608 if (D.getDeclSpec().isThreadSpecified()) 3609 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3610 3611 DiagnoseFunctionSpecifiers(D); 3612 3613 // Check that there are no default arguments inside the type of this 3614 // parameter (C++ only). 3615 if (getLangOptions().CPlusPlus) 3616 CheckExtraCXXDefaultArguments(D); 3617 3618 DeclaratorInfo *DInfo = 0; 3619 TagDecl *OwnedDecl = 0; 3620 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3621 3622 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3623 // C++ [dcl.fct]p6: 3624 // Types shall not be defined in return or parameter types. 3625 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3626 << Context.getTypeDeclType(OwnedDecl); 3627 } 3628 3629 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3630 // Can this happen for params? We already checked that they don't conflict 3631 // among each other. Here they can only shadow globals, which is ok. 3632 IdentifierInfo *II = D.getIdentifier(); 3633 if (II) { 3634 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3635 if (PrevDecl->isTemplateParameter()) { 3636 // Maybe we will complain about the shadowed template parameter. 3637 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3638 // Just pretend that we didn't see the previous declaration. 3639 PrevDecl = 0; 3640 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3641 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3642 3643 // Recover by removing the name 3644 II = 0; 3645 D.SetIdentifier(0, D.getIdentifierLoc()); 3646 } 3647 } 3648 } 3649 3650 // Parameters can not be abstract class types. 3651 // For record types, this is done by the AbstractClassUsageDiagnoser once 3652 // the class has been completely parsed. 3653 if (!CurContext->isRecord() && 3654 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3655 diag::err_abstract_type_in_decl, 3656 AbstractParamType)) 3657 D.setInvalidType(true); 3658 3659 QualType T = adjustParameterType(parmDeclType); 3660 3661 ParmVarDecl *New 3662 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3663 T, DInfo, StorageClass, 0); 3664 3665 if (D.isInvalidType()) 3666 New->setInvalidDecl(); 3667 3668 // Parameter declarators cannot be interface types. All ObjC objects are 3669 // passed by reference. 3670 if (T->isObjCInterfaceType()) { 3671 Diag(D.getIdentifierLoc(), 3672 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3673 New->setInvalidDecl(); 3674 } 3675 3676 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3677 if (D.getCXXScopeSpec().isSet()) { 3678 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3679 << D.getCXXScopeSpec().getRange(); 3680 New->setInvalidDecl(); 3681 } 3682 3683 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3684 // duration shall not be qualified by an address-space qualifier." 3685 // Since all parameters have automatic store duration, they can not have 3686 // an address space. 3687 if (T.getAddressSpace() != 0) { 3688 Diag(D.getIdentifierLoc(), 3689 diag::err_arg_with_address_space); 3690 New->setInvalidDecl(); 3691 } 3692 3693 3694 // Add the parameter declaration into this scope. 3695 S->AddDecl(DeclPtrTy::make(New)); 3696 if (II) 3697 IdResolver.AddDecl(New); 3698 3699 ProcessDeclAttributes(S, New, D); 3700 3701 if (New->hasAttr<BlocksAttr>()) { 3702 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3703 } 3704 return DeclPtrTy::make(New); 3705} 3706 3707void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3708 SourceLocation LocAfterDecls) { 3709 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3710 "Not a function declarator!"); 3711 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3712 3713 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3714 // for a K&R function. 3715 if (!FTI.hasPrototype) { 3716 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3717 --i; 3718 if (FTI.ArgInfo[i].Param == 0) { 3719 llvm::SmallString<256> Code; 3720 llvm::raw_svector_ostream(Code) << " int " 3721 << FTI.ArgInfo[i].Ident->getName() 3722 << ";\n"; 3723 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3724 << FTI.ArgInfo[i].Ident 3725 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3726 3727 // Implicitly declare the argument as type 'int' for lack of a better 3728 // type. 3729 DeclSpec DS; 3730 const char* PrevSpec; // unused 3731 unsigned DiagID; // unused 3732 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3733 PrevSpec, DiagID); 3734 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3735 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3736 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3737 } 3738 } 3739 } 3740} 3741 3742Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3743 Declarator &D) { 3744 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3745 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3746 "Not a function declarator!"); 3747 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3748 3749 if (FTI.hasPrototype) { 3750 // FIXME: Diagnose arguments without names in C. 3751 } 3752 3753 Scope *ParentScope = FnBodyScope->getParent(); 3754 3755 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3756 MultiTemplateParamsArg(*this), 3757 /*IsFunctionDefinition=*/true); 3758 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3759} 3760 3761Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3762 if (!D) 3763 return D; 3764 FunctionDecl *FD = 0; 3765 3766 if (FunctionTemplateDecl *FunTmpl 3767 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3768 FD = FunTmpl->getTemplatedDecl(); 3769 else 3770 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3771 3772 CurFunctionNeedsScopeChecking = false; 3773 3774 // See if this is a redefinition. 3775 const FunctionDecl *Definition; 3776 if (FD->getBody(Definition)) { 3777 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3778 Diag(Definition->getLocation(), diag::note_previous_definition); 3779 } 3780 3781 // Builtin functions cannot be defined. 3782 if (unsigned BuiltinID = FD->getBuiltinID()) { 3783 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3784 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3785 FD->setInvalidDecl(); 3786 } 3787 } 3788 3789 // The return type of a function definition must be complete 3790 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3791 QualType ResultType = FD->getResultType(); 3792 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3793 !FD->isInvalidDecl() && 3794 RequireCompleteType(FD->getLocation(), ResultType, 3795 diag::err_func_def_incomplete_result)) 3796 FD->setInvalidDecl(); 3797 3798 // GNU warning -Wmissing-prototypes: 3799 // Warn if a global function is defined without a previous 3800 // prototype declaration. This warning is issued even if the 3801 // definition itself provides a prototype. The aim is to detect 3802 // global functions that fail to be declared in header files. 3803 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3804 !FD->isMain()) { 3805 bool MissingPrototype = true; 3806 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3807 Prev; Prev = Prev->getPreviousDeclaration()) { 3808 // Ignore any declarations that occur in function or method 3809 // scope, because they aren't visible from the header. 3810 if (Prev->getDeclContext()->isFunctionOrMethod()) 3811 continue; 3812 3813 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3814 break; 3815 } 3816 3817 if (MissingPrototype) 3818 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3819 } 3820 3821 if (FnBodyScope) 3822 PushDeclContext(FnBodyScope, FD); 3823 3824 // Check the validity of our function parameters 3825 CheckParmsForFunctionDef(FD); 3826 3827 // Introduce our parameters into the function scope 3828 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3829 ParmVarDecl *Param = FD->getParamDecl(p); 3830 Param->setOwningFunction(FD); 3831 3832 // If this has an identifier, add it to the scope stack. 3833 if (Param->getIdentifier() && FnBodyScope) 3834 PushOnScopeChains(Param, FnBodyScope); 3835 } 3836 3837 // Checking attributes of current function definition 3838 // dllimport attribute. 3839 if (FD->getAttr<DLLImportAttr>() && 3840 (!FD->getAttr<DLLExportAttr>())) { 3841 // dllimport attribute cannot be applied to definition. 3842 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3843 Diag(FD->getLocation(), 3844 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3845 << "dllimport"; 3846 FD->setInvalidDecl(); 3847 return DeclPtrTy::make(FD); 3848 } else { 3849 // If a symbol previously declared dllimport is later defined, the 3850 // attribute is ignored in subsequent references, and a warning is 3851 // emitted. 3852 Diag(FD->getLocation(), 3853 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3854 << FD->getNameAsCString() << "dllimport"; 3855 } 3856 } 3857 return DeclPtrTy::make(FD); 3858} 3859 3860Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3861 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3862} 3863 3864Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3865 bool IsInstantiation) { 3866 Decl *dcl = D.getAs<Decl>(); 3867 Stmt *Body = BodyArg.takeAs<Stmt>(); 3868 3869 FunctionDecl *FD = 0; 3870 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3871 if (FunTmpl) 3872 FD = FunTmpl->getTemplatedDecl(); 3873 else 3874 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3875 3876 if (FD) { 3877 FD->setBody(Body); 3878 if (FD->isMain()) 3879 // C and C++ allow for main to automagically return 0. 3880 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3881 FD->setHasImplicitReturnZero(true); 3882 else 3883 CheckFallThroughForFunctionDef(FD, Body); 3884 3885 if (!FD->isInvalidDecl()) 3886 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3887 3888 // C++ [basic.def.odr]p2: 3889 // [...] A virtual member function is used if it is not pure. [...] 3890 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3891 if (Method->isVirtual() && !Method->isPure()) 3892 MarkDeclarationReferenced(Method->getLocation(), Method); 3893 3894 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3895 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3896 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3897 MD->setBody(Body); 3898 CheckFallThroughForFunctionDef(MD, Body); 3899 MD->setEndLoc(Body->getLocEnd()); 3900 3901 if (!MD->isInvalidDecl()) 3902 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3903 } else { 3904 Body->Destroy(Context); 3905 return DeclPtrTy(); 3906 } 3907 if (!IsInstantiation) 3908 PopDeclContext(); 3909 3910 // Verify and clean out per-function state. 3911 3912 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3913 3914 // Check goto/label use. 3915 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3916 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3917 LabelStmt *L = I->second; 3918 3919 // Verify that we have no forward references left. If so, there was a goto 3920 // or address of a label taken, but no definition of it. Label fwd 3921 // definitions are indicated with a null substmt. 3922 if (L->getSubStmt() != 0) 3923 continue; 3924 3925 // Emit error. 3926 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3927 3928 // At this point, we have gotos that use the bogus label. Stitch it into 3929 // the function body so that they aren't leaked and that the AST is well 3930 // formed. 3931 if (Body == 0) { 3932 // The whole function wasn't parsed correctly, just delete this. 3933 L->Destroy(Context); 3934 continue; 3935 } 3936 3937 // Otherwise, the body is valid: we want to stitch the label decl into the 3938 // function somewhere so that it is properly owned and so that the goto 3939 // has a valid target. Do this by creating a new compound stmt with the 3940 // label in it. 3941 3942 // Give the label a sub-statement. 3943 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3944 3945 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3946 cast<CXXTryStmt>(Body)->getTryBlock() : 3947 cast<CompoundStmt>(Body); 3948 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3949 Elements.push_back(L); 3950 Compound->setStmts(Context, &Elements[0], Elements.size()); 3951 } 3952 FunctionLabelMap.clear(); 3953 3954 if (!Body) return D; 3955 3956 // Verify that that gotos and switch cases don't jump into scopes illegally. 3957 if (CurFunctionNeedsScopeChecking) 3958 DiagnoseInvalidJumps(Body); 3959 3960 // C++ constructors that have function-try-blocks can't have return 3961 // statements in the handlers of that block. (C++ [except.handle]p14) 3962 // Verify this. 3963 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3964 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3965 3966 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3967 computeBaseOrMembersToDestroy(Destructor); 3968 return D; 3969} 3970 3971/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3972/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3973NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3974 IdentifierInfo &II, Scope *S) { 3975 // Before we produce a declaration for an implicitly defined 3976 // function, see whether there was a locally-scoped declaration of 3977 // this name as a function or variable. If so, use that 3978 // (non-visible) declaration, and complain about it. 3979 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3980 = LocallyScopedExternalDecls.find(&II); 3981 if (Pos != LocallyScopedExternalDecls.end()) { 3982 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3983 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3984 return Pos->second; 3985 } 3986 3987 // Extension in C99. Legal in C90, but warn about it. 3988 if (II.getName().startswith("__builtin_")) 3989 Diag(Loc, diag::warn_builtin_unknown) << &II; 3990 else if (getLangOptions().C99) 3991 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3992 else 3993 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3994 3995 // Set a Declarator for the implicit definition: int foo(); 3996 const char *Dummy; 3997 DeclSpec DS; 3998 unsigned DiagID; 3999 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4000 Error = Error; // Silence warning. 4001 assert(!Error && "Error setting up implicit decl!"); 4002 Declarator D(DS, Declarator::BlockContext); 4003 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4004 0, 0, false, SourceLocation(), 4005 false, 0,0,0, Loc, Loc, D), 4006 SourceLocation()); 4007 D.SetIdentifier(&II, Loc); 4008 4009 // Insert this function into translation-unit scope. 4010 4011 DeclContext *PrevDC = CurContext; 4012 CurContext = Context.getTranslationUnitDecl(); 4013 4014 FunctionDecl *FD = 4015 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4016 FD->setImplicit(); 4017 4018 CurContext = PrevDC; 4019 4020 AddKnownFunctionAttributes(FD); 4021 4022 return FD; 4023} 4024 4025/// \brief Adds any function attributes that we know a priori based on 4026/// the declaration of this function. 4027/// 4028/// These attributes can apply both to implicitly-declared builtins 4029/// (like __builtin___printf_chk) or to library-declared functions 4030/// like NSLog or printf. 4031void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4032 if (FD->isInvalidDecl()) 4033 return; 4034 4035 // If this is a built-in function, map its builtin attributes to 4036 // actual attributes. 4037 if (unsigned BuiltinID = FD->getBuiltinID()) { 4038 // Handle printf-formatting attributes. 4039 unsigned FormatIdx; 4040 bool HasVAListArg; 4041 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4042 if (!FD->getAttr<FormatAttr>()) 4043 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4044 HasVAListArg ? 0 : FormatIdx + 2)); 4045 } 4046 4047 // Mark const if we don't care about errno and that is the only 4048 // thing preventing the function from being const. This allows 4049 // IRgen to use LLVM intrinsics for such functions. 4050 if (!getLangOptions().MathErrno && 4051 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4052 if (!FD->getAttr<ConstAttr>()) 4053 FD->addAttr(::new (Context) ConstAttr()); 4054 } 4055 4056 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4057 FD->addAttr(::new (Context) NoReturnAttr()); 4058 } 4059 4060 IdentifierInfo *Name = FD->getIdentifier(); 4061 if (!Name) 4062 return; 4063 if ((!getLangOptions().CPlusPlus && 4064 FD->getDeclContext()->isTranslationUnit()) || 4065 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4066 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4067 LinkageSpecDecl::lang_c)) { 4068 // Okay: this could be a libc/libm/Objective-C function we know 4069 // about. 4070 } else 4071 return; 4072 4073 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4074 // FIXME: NSLog and NSLogv should be target specific 4075 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4076 // FIXME: We known better than our headers. 4077 const_cast<FormatAttr *>(Format)->setType("printf"); 4078 } else 4079 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4080 Name->isStr("NSLogv") ? 0 : 2)); 4081 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4082 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4083 // target-specific builtins, perhaps? 4084 if (!FD->getAttr<FormatAttr>()) 4085 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4086 Name->isStr("vasprintf") ? 0 : 3)); 4087 } 4088} 4089 4090TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4091 DeclaratorInfo *DInfo) { 4092 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4093 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4094 4095 if (!DInfo) { 4096 assert(D.isInvalidType() && "no declarator info for valid type"); 4097 DInfo = Context.getTrivialDeclaratorInfo(T); 4098 } 4099 4100 // Scope manipulation handled by caller. 4101 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4102 D.getIdentifierLoc(), 4103 D.getIdentifier(), 4104 DInfo); 4105 4106 if (const TagType *TT = T->getAs<TagType>()) { 4107 TagDecl *TD = TT->getDecl(); 4108 4109 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4110 // keep track of the TypedefDecl. 4111 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4112 TD->setTypedefForAnonDecl(NewTD); 4113 } 4114 4115 if (D.isInvalidType()) 4116 NewTD->setInvalidDecl(); 4117 return NewTD; 4118} 4119 4120 4121/// \brief Determine whether a tag with a given kind is acceptable 4122/// as a redeclaration of the given tag declaration. 4123/// 4124/// \returns true if the new tag kind is acceptable, false otherwise. 4125bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4126 TagDecl::TagKind NewTag, 4127 SourceLocation NewTagLoc, 4128 const IdentifierInfo &Name) { 4129 // C++ [dcl.type.elab]p3: 4130 // The class-key or enum keyword present in the 4131 // elaborated-type-specifier shall agree in kind with the 4132 // declaration to which the name in theelaborated-type-specifier 4133 // refers. This rule also applies to the form of 4134 // elaborated-type-specifier that declares a class-name or 4135 // friend class since it can be construed as referring to the 4136 // definition of the class. Thus, in any 4137 // elaborated-type-specifier, the enum keyword shall be used to 4138 // refer to an enumeration (7.2), the union class-keyshall be 4139 // used to refer to a union (clause 9), and either the class or 4140 // struct class-key shall be used to refer to a class (clause 9) 4141 // declared using the class or struct class-key. 4142 TagDecl::TagKind OldTag = Previous->getTagKind(); 4143 if (OldTag == NewTag) 4144 return true; 4145 4146 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4147 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4148 // Warn about the struct/class tag mismatch. 4149 bool isTemplate = false; 4150 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4151 isTemplate = Record->getDescribedClassTemplate(); 4152 4153 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4154 << (NewTag == TagDecl::TK_class) 4155 << isTemplate << &Name 4156 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4157 OldTag == TagDecl::TK_class? "class" : "struct"); 4158 Diag(Previous->getLocation(), diag::note_previous_use); 4159 return true; 4160 } 4161 return false; 4162} 4163 4164/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4165/// former case, Name will be non-null. In the later case, Name will be null. 4166/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4167/// reference/declaration/definition of a tag. 4168Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4169 SourceLocation KWLoc, const CXXScopeSpec &SS, 4170 IdentifierInfo *Name, SourceLocation NameLoc, 4171 AttributeList *Attr, AccessSpecifier AS, 4172 MultiTemplateParamsArg TemplateParameterLists, 4173 bool &OwnedDecl, bool &IsDependent) { 4174 // If this is not a definition, it must have a name. 4175 assert((Name != 0 || TUK == TUK_Definition) && 4176 "Nameless record must be a definition!"); 4177 4178 OwnedDecl = false; 4179 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4180 4181 // FIXME: Check explicit specializations more carefully. 4182 bool isExplicitSpecialization = false; 4183 if (TUK != TUK_Reference) { 4184 if (TemplateParameterList *TemplateParams 4185 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4186 (TemplateParameterList**)TemplateParameterLists.get(), 4187 TemplateParameterLists.size(), 4188 isExplicitSpecialization)) { 4189 if (TemplateParams->size() > 0) { 4190 // This is a declaration or definition of a class template (which may 4191 // be a member of another template). 4192 OwnedDecl = false; 4193 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4194 SS, Name, NameLoc, Attr, 4195 TemplateParams, 4196 AS); 4197 TemplateParameterLists.release(); 4198 return Result.get(); 4199 } else { 4200 // The "template<>" header is extraneous. 4201 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4202 << ElaboratedType::getNameForTagKind(Kind) << Name; 4203 isExplicitSpecialization = true; 4204 } 4205 } 4206 4207 TemplateParameterLists.release(); 4208 } 4209 4210 DeclContext *SearchDC = CurContext; 4211 DeclContext *DC = CurContext; 4212 NamedDecl *PrevDecl = 0; 4213 bool isStdBadAlloc = false; 4214 bool Invalid = false; 4215 4216 bool RedeclarationOnly = (TUK != TUK_Reference); 4217 4218 if (Name && SS.isNotEmpty()) { 4219 // We have a nested-name tag ('struct foo::bar'). 4220 4221 // Check for invalid 'foo::'. 4222 if (SS.isInvalid()) { 4223 Name = 0; 4224 goto CreateNewDecl; 4225 } 4226 4227 // If this is a friend or a reference to a class in a dependent 4228 // context, don't try to make a decl for it. 4229 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4230 DC = computeDeclContext(SS, false); 4231 if (!DC) { 4232 IsDependent = true; 4233 return DeclPtrTy(); 4234 } 4235 } 4236 4237 if (RequireCompleteDeclContext(SS)) 4238 return DeclPtrTy::make((Decl *)0); 4239 4240 DC = computeDeclContext(SS, true); 4241 SearchDC = DC; 4242 // Look-up name inside 'foo::'. 4243 LookupResult R; 4244 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4245 4246 if (R.isAmbiguous()) { 4247 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4248 return DeclPtrTy(); 4249 } 4250 4251 if (R.getKind() == LookupResult::Found) 4252 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4253 4254 // A tag 'foo::bar' must already exist. 4255 if (!PrevDecl) { 4256 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4257 Name = 0; 4258 Invalid = true; 4259 goto CreateNewDecl; 4260 } 4261 } else if (Name) { 4262 // If this is a named struct, check to see if there was a previous forward 4263 // declaration or definition. 4264 // FIXME: We're looking into outer scopes here, even when we 4265 // shouldn't be. Doing so can result in ambiguities that we 4266 // shouldn't be diagnosing. 4267 LookupResult R; 4268 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4269 if (R.isAmbiguous()) { 4270 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4271 // FIXME: This is not best way to recover from case like: 4272 // 4273 // struct S s; 4274 // 4275 // causes needless "incomplete type" error later. 4276 Name = 0; 4277 PrevDecl = 0; 4278 Invalid = true; 4279 } else 4280 PrevDecl = R.getAsSingleDecl(Context); 4281 4282 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4283 // FIXME: This makes sure that we ignore the contexts associated 4284 // with C structs, unions, and enums when looking for a matching 4285 // tag declaration or definition. See the similar lookup tweak 4286 // in Sema::LookupName; is there a better way to deal with this? 4287 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4288 SearchDC = SearchDC->getParent(); 4289 } 4290 } 4291 4292 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4293 // Maybe we will complain about the shadowed template parameter. 4294 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4295 // Just pretend that we didn't see the previous declaration. 4296 PrevDecl = 0; 4297 } 4298 4299 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4300 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4301 // This is a declaration of or a reference to "std::bad_alloc". 4302 isStdBadAlloc = true; 4303 4304 if (!PrevDecl && StdBadAlloc) { 4305 // std::bad_alloc has been implicitly declared (but made invisible to 4306 // name lookup). Fill in this implicit declaration as the previous 4307 // declaration, so that the declarations get chained appropriately. 4308 PrevDecl = StdBadAlloc; 4309 } 4310 } 4311 4312 if (PrevDecl) { 4313 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4314 // If this is a use of a previous tag, or if the tag is already declared 4315 // in the same scope (so that the definition/declaration completes or 4316 // rementions the tag), reuse the decl. 4317 if (TUK == TUK_Reference || TUK == TUK_Friend || 4318 isDeclInScope(PrevDecl, SearchDC, S)) { 4319 // Make sure that this wasn't declared as an enum and now used as a 4320 // struct or something similar. 4321 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4322 bool SafeToContinue 4323 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4324 Kind != TagDecl::TK_enum); 4325 if (SafeToContinue) 4326 Diag(KWLoc, diag::err_use_with_wrong_tag) 4327 << Name 4328 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4329 PrevTagDecl->getKindName()); 4330 else 4331 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4332 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4333 4334 if (SafeToContinue) 4335 Kind = PrevTagDecl->getTagKind(); 4336 else { 4337 // Recover by making this an anonymous redefinition. 4338 Name = 0; 4339 PrevDecl = 0; 4340 Invalid = true; 4341 } 4342 } 4343 4344 if (!Invalid) { 4345 // If this is a use, just return the declaration we found. 4346 4347 // FIXME: In the future, return a variant or some other clue 4348 // for the consumer of this Decl to know it doesn't own it. 4349 // For our current ASTs this shouldn't be a problem, but will 4350 // need to be changed with DeclGroups. 4351 if (TUK == TUK_Reference || TUK == TUK_Friend) 4352 return DeclPtrTy::make(PrevDecl); 4353 4354 // Diagnose attempts to redefine a tag. 4355 if (TUK == TUK_Definition) { 4356 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4357 // If we're defining a specialization and the previous definition 4358 // is from an implicit instantiation, don't emit an error 4359 // here; we'll catch this in the general case below. 4360 if (!isExplicitSpecialization || 4361 !isa<CXXRecordDecl>(Def) || 4362 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4363 == TSK_ExplicitSpecialization) { 4364 Diag(NameLoc, diag::err_redefinition) << Name; 4365 Diag(Def->getLocation(), diag::note_previous_definition); 4366 // If this is a redefinition, recover by making this 4367 // struct be anonymous, which will make any later 4368 // references get the previous definition. 4369 Name = 0; 4370 PrevDecl = 0; 4371 Invalid = true; 4372 } 4373 } else { 4374 // If the type is currently being defined, complain 4375 // about a nested redefinition. 4376 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4377 if (Tag->isBeingDefined()) { 4378 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4379 Diag(PrevTagDecl->getLocation(), 4380 diag::note_previous_definition); 4381 Name = 0; 4382 PrevDecl = 0; 4383 Invalid = true; 4384 } 4385 } 4386 4387 // Okay, this is definition of a previously declared or referenced 4388 // tag PrevDecl. We're going to create a new Decl for it. 4389 } 4390 } 4391 // If we get here we have (another) forward declaration or we 4392 // have a definition. Just create a new decl. 4393 4394 } else { 4395 // If we get here, this is a definition of a new tag type in a nested 4396 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4397 // new decl/type. We set PrevDecl to NULL so that the entities 4398 // have distinct types. 4399 PrevDecl = 0; 4400 } 4401 // If we get here, we're going to create a new Decl. If PrevDecl 4402 // is non-NULL, it's a definition of the tag declared by 4403 // PrevDecl. If it's NULL, we have a new definition. 4404 } else { 4405 // PrevDecl is a namespace, template, or anything else 4406 // that lives in the IDNS_Tag identifier namespace. 4407 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4408 // The tag name clashes with a namespace name, issue an error and 4409 // recover by making this tag be anonymous. 4410 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4411 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4412 Name = 0; 4413 PrevDecl = 0; 4414 Invalid = true; 4415 } else { 4416 // The existing declaration isn't relevant to us; we're in a 4417 // new scope, so clear out the previous declaration. 4418 PrevDecl = 0; 4419 } 4420 } 4421 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4422 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4423 // C++ [basic.scope.pdecl]p5: 4424 // -- for an elaborated-type-specifier of the form 4425 // 4426 // class-key identifier 4427 // 4428 // if the elaborated-type-specifier is used in the 4429 // decl-specifier-seq or parameter-declaration-clause of a 4430 // function defined in namespace scope, the identifier is 4431 // declared as a class-name in the namespace that contains 4432 // the declaration; otherwise, except as a friend 4433 // declaration, the identifier is declared in the smallest 4434 // non-class, non-function-prototype scope that contains the 4435 // declaration. 4436 // 4437 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4438 // C structs and unions. 4439 // 4440 // GNU C also supports this behavior as part of its incomplete 4441 // enum types extension, while GNU C++ does not. 4442 // 4443 // Find the context where we'll be declaring the tag. 4444 // FIXME: We would like to maintain the current DeclContext as the 4445 // lexical context, 4446 while (SearchDC->isRecord()) 4447 SearchDC = SearchDC->getParent(); 4448 4449 // Find the scope where we'll be declaring the tag. 4450 while (S->isClassScope() || 4451 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4452 ((S->getFlags() & Scope::DeclScope) == 0) || 4453 (S->getEntity() && 4454 ((DeclContext *)S->getEntity())->isTransparentContext())) 4455 S = S->getParent(); 4456 4457 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4458 // C++ [namespace.memdef]p3: 4459 // If a friend declaration in a non-local class first declares a 4460 // class or function, the friend class or function is a member of 4461 // the innermost enclosing namespace. 4462 while (!SearchDC->isFileContext()) 4463 SearchDC = SearchDC->getParent(); 4464 4465 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4466 while (S->getEntity() != SearchDC) 4467 S = S->getParent(); 4468 } 4469 4470CreateNewDecl: 4471 4472 // If there is an identifier, use the location of the identifier as the 4473 // location of the decl, otherwise use the location of the struct/union 4474 // keyword. 4475 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4476 4477 // Otherwise, create a new declaration. If there is a previous 4478 // declaration of the same entity, the two will be linked via 4479 // PrevDecl. 4480 TagDecl *New; 4481 4482 if (Kind == TagDecl::TK_enum) { 4483 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4484 // enum X { A, B, C } D; D should chain to X. 4485 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4486 cast_or_null<EnumDecl>(PrevDecl)); 4487 // If this is an undefined enum, warn. 4488 if (TUK != TUK_Definition && !Invalid) { 4489 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4490 : diag::ext_forward_ref_enum; 4491 Diag(Loc, DK); 4492 } 4493 } else { 4494 // struct/union/class 4495 4496 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4497 // struct X { int A; } D; D should chain to X. 4498 if (getLangOptions().CPlusPlus) { 4499 // FIXME: Look for a way to use RecordDecl for simple structs. 4500 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4501 cast_or_null<CXXRecordDecl>(PrevDecl)); 4502 4503 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4504 StdBadAlloc = cast<CXXRecordDecl>(New); 4505 } else 4506 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4507 cast_or_null<RecordDecl>(PrevDecl)); 4508 } 4509 4510 if (Kind != TagDecl::TK_enum) { 4511 // Handle #pragma pack: if the #pragma pack stack has non-default 4512 // alignment, make up a packed attribute for this decl. These 4513 // attributes are checked when the ASTContext lays out the 4514 // structure. 4515 // 4516 // It is important for implementing the correct semantics that this 4517 // happen here (in act on tag decl). The #pragma pack stack is 4518 // maintained as a result of parser callbacks which can occur at 4519 // many points during the parsing of a struct declaration (because 4520 // the #pragma tokens are effectively skipped over during the 4521 // parsing of the struct). 4522 if (unsigned Alignment = getPragmaPackAlignment()) 4523 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4524 } 4525 4526 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4527 // C++ [dcl.typedef]p3: 4528 // [...] Similarly, in a given scope, a class or enumeration 4529 // shall not be declared with the same name as a typedef-name 4530 // that is declared in that scope and refers to a type other 4531 // than the class or enumeration itself. 4532 LookupResult Lookup; 4533 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4534 TypedefDecl *PrevTypedef = 0; 4535 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4536 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4537 4538 NamedDecl *PrevTypedefNamed = PrevTypedef; 4539 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4540 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4541 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4542 Diag(Loc, diag::err_tag_definition_of_typedef) 4543 << Context.getTypeDeclType(New) 4544 << PrevTypedef->getUnderlyingType(); 4545 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4546 Invalid = true; 4547 } 4548 } 4549 4550 // If this is a specialization of a member class (of a class template), 4551 // check the specialization. 4552 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4553 Invalid = true; 4554 4555 if (Invalid) 4556 New->setInvalidDecl(); 4557 4558 if (Attr) 4559 ProcessDeclAttributeList(S, New, Attr); 4560 4561 // If we're declaring or defining a tag in function prototype scope 4562 // in C, note that this type can only be used within the function. 4563 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4564 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4565 4566 // Set the lexical context. If the tag has a C++ scope specifier, the 4567 // lexical context will be different from the semantic context. 4568 New->setLexicalDeclContext(CurContext); 4569 4570 // Mark this as a friend decl if applicable. 4571 if (TUK == TUK_Friend) 4572 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4573 4574 // Set the access specifier. 4575 if (!Invalid && TUK != TUK_Friend) 4576 SetMemberAccessSpecifier(New, PrevDecl, AS); 4577 4578 if (TUK == TUK_Definition) 4579 New->startDefinition(); 4580 4581 // If this has an identifier, add it to the scope stack. 4582 if (TUK == TUK_Friend) { 4583 // We might be replacing an existing declaration in the lookup tables; 4584 // if so, borrow its access specifier. 4585 if (PrevDecl) 4586 New->setAccess(PrevDecl->getAccess()); 4587 4588 // Friend tag decls are visible in fairly strange ways. 4589 if (!CurContext->isDependentContext()) { 4590 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4591 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4592 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4593 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4594 } 4595 } else if (Name) { 4596 S = getNonFieldDeclScope(S); 4597 PushOnScopeChains(New, S); 4598 } else { 4599 CurContext->addDecl(New); 4600 } 4601 4602 // If this is the C FILE type, notify the AST context. 4603 if (IdentifierInfo *II = New->getIdentifier()) 4604 if (!New->isInvalidDecl() && 4605 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4606 II->isStr("FILE")) 4607 Context.setFILEDecl(New); 4608 4609 OwnedDecl = true; 4610 return DeclPtrTy::make(New); 4611} 4612 4613void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4614 AdjustDeclIfTemplate(TagD); 4615 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4616 4617 // Enter the tag context. 4618 PushDeclContext(S, Tag); 4619 4620 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4621 FieldCollector->StartClass(); 4622 4623 if (Record->getIdentifier()) { 4624 // C++ [class]p2: 4625 // [...] The class-name is also inserted into the scope of the 4626 // class itself; this is known as the injected-class-name. For 4627 // purposes of access checking, the injected-class-name is treated 4628 // as if it were a public member name. 4629 CXXRecordDecl *InjectedClassName 4630 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4631 CurContext, Record->getLocation(), 4632 Record->getIdentifier(), 4633 Record->getTagKeywordLoc(), 4634 Record); 4635 InjectedClassName->setImplicit(); 4636 InjectedClassName->setAccess(AS_public); 4637 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4638 InjectedClassName->setDescribedClassTemplate(Template); 4639 PushOnScopeChains(InjectedClassName, S); 4640 assert(InjectedClassName->isInjectedClassName() && 4641 "Broken injected-class-name"); 4642 } 4643 } 4644} 4645 4646void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4647 SourceLocation RBraceLoc) { 4648 AdjustDeclIfTemplate(TagD); 4649 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4650 Tag->setRBraceLoc(RBraceLoc); 4651 4652 if (isa<CXXRecordDecl>(Tag)) 4653 FieldCollector->FinishClass(); 4654 4655 // Exit this scope of this tag's definition. 4656 PopDeclContext(); 4657 4658 // Notify the consumer that we've defined a tag. 4659 Consumer.HandleTagDeclDefinition(Tag); 4660} 4661 4662// Note that FieldName may be null for anonymous bitfields. 4663bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4664 QualType FieldTy, const Expr *BitWidth, 4665 bool *ZeroWidth) { 4666 // Default to true; that shouldn't confuse checks for emptiness 4667 if (ZeroWidth) 4668 *ZeroWidth = true; 4669 4670 // C99 6.7.2.1p4 - verify the field type. 4671 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4672 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4673 // Handle incomplete types with specific error. 4674 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4675 return true; 4676 if (FieldName) 4677 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4678 << FieldName << FieldTy << BitWidth->getSourceRange(); 4679 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4680 << FieldTy << BitWidth->getSourceRange(); 4681 } 4682 4683 // If the bit-width is type- or value-dependent, don't try to check 4684 // it now. 4685 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4686 return false; 4687 4688 llvm::APSInt Value; 4689 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4690 return true; 4691 4692 if (Value != 0 && ZeroWidth) 4693 *ZeroWidth = false; 4694 4695 // Zero-width bitfield is ok for anonymous field. 4696 if (Value == 0 && FieldName) 4697 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4698 4699 if (Value.isSigned() && Value.isNegative()) { 4700 if (FieldName) 4701 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4702 << FieldName << Value.toString(10); 4703 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4704 << Value.toString(10); 4705 } 4706 4707 if (!FieldTy->isDependentType()) { 4708 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4709 if (Value.getZExtValue() > TypeSize) { 4710 if (FieldName) 4711 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4712 << FieldName << (unsigned)TypeSize; 4713 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4714 << (unsigned)TypeSize; 4715 } 4716 } 4717 4718 return false; 4719} 4720 4721/// ActOnField - Each field of a struct/union/class is passed into this in order 4722/// to create a FieldDecl object for it. 4723Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4724 SourceLocation DeclStart, 4725 Declarator &D, ExprTy *BitfieldWidth) { 4726 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4727 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4728 AS_public); 4729 return DeclPtrTy::make(Res); 4730} 4731 4732/// HandleField - Analyze a field of a C struct or a C++ data member. 4733/// 4734FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4735 SourceLocation DeclStart, 4736 Declarator &D, Expr *BitWidth, 4737 AccessSpecifier AS) { 4738 IdentifierInfo *II = D.getIdentifier(); 4739 SourceLocation Loc = DeclStart; 4740 if (II) Loc = D.getIdentifierLoc(); 4741 4742 DeclaratorInfo *DInfo = 0; 4743 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4744 if (getLangOptions().CPlusPlus) 4745 CheckExtraCXXDefaultArguments(D); 4746 4747 DiagnoseFunctionSpecifiers(D); 4748 4749 if (D.getDeclSpec().isThreadSpecified()) 4750 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4751 4752 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4753 4754 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4755 // Maybe we will complain about the shadowed template parameter. 4756 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4757 // Just pretend that we didn't see the previous declaration. 4758 PrevDecl = 0; 4759 } 4760 4761 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4762 PrevDecl = 0; 4763 4764 bool Mutable 4765 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4766 SourceLocation TSSL = D.getSourceRange().getBegin(); 4767 FieldDecl *NewFD 4768 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4769 AS, PrevDecl, &D); 4770 if (NewFD->isInvalidDecl() && PrevDecl) { 4771 // Don't introduce NewFD into scope; there's already something 4772 // with the same name in the same scope. 4773 } else if (II) { 4774 PushOnScopeChains(NewFD, S); 4775 } else 4776 Record->addDecl(NewFD); 4777 4778 return NewFD; 4779} 4780 4781/// \brief Build a new FieldDecl and check its well-formedness. 4782/// 4783/// This routine builds a new FieldDecl given the fields name, type, 4784/// record, etc. \p PrevDecl should refer to any previous declaration 4785/// with the same name and in the same scope as the field to be 4786/// created. 4787/// 4788/// \returns a new FieldDecl. 4789/// 4790/// \todo The Declarator argument is a hack. It will be removed once 4791FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4792 DeclaratorInfo *DInfo, 4793 RecordDecl *Record, SourceLocation Loc, 4794 bool Mutable, Expr *BitWidth, 4795 SourceLocation TSSL, 4796 AccessSpecifier AS, NamedDecl *PrevDecl, 4797 Declarator *D) { 4798 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4799 bool InvalidDecl = false; 4800 if (D) InvalidDecl = D->isInvalidType(); 4801 4802 // If we receive a broken type, recover by assuming 'int' and 4803 // marking this declaration as invalid. 4804 if (T.isNull()) { 4805 InvalidDecl = true; 4806 T = Context.IntTy; 4807 } 4808 4809 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4810 // than a variably modified type. 4811 if (T->isVariablyModifiedType()) { 4812 bool SizeIsNegative; 4813 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4814 SizeIsNegative); 4815 if (!FixedTy.isNull()) { 4816 Diag(Loc, diag::warn_illegal_constant_array_size); 4817 T = FixedTy; 4818 } else { 4819 if (SizeIsNegative) 4820 Diag(Loc, diag::err_typecheck_negative_array_size); 4821 else 4822 Diag(Loc, diag::err_typecheck_field_variable_size); 4823 InvalidDecl = true; 4824 } 4825 } 4826 4827 // Fields can not have abstract class types 4828 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4829 AbstractFieldType)) 4830 InvalidDecl = true; 4831 4832 bool ZeroWidth = false; 4833 // If this is declared as a bit-field, check the bit-field. 4834 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4835 InvalidDecl = true; 4836 DeleteExpr(BitWidth); 4837 BitWidth = 0; 4838 ZeroWidth = false; 4839 } 4840 4841 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4842 BitWidth, Mutable); 4843 if (InvalidDecl) 4844 NewFD->setInvalidDecl(); 4845 4846 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4847 Diag(Loc, diag::err_duplicate_member) << II; 4848 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4849 NewFD->setInvalidDecl(); 4850 } 4851 4852 if (getLangOptions().CPlusPlus) { 4853 QualType EltTy = Context.getBaseElementType(T); 4854 4855 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4856 4857 if (!T->isPODType()) 4858 CXXRecord->setPOD(false); 4859 if (!ZeroWidth) 4860 CXXRecord->setEmpty(false); 4861 4862 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4863 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4864 4865 if (!RDecl->hasTrivialConstructor()) 4866 CXXRecord->setHasTrivialConstructor(false); 4867 if (!RDecl->hasTrivialCopyConstructor()) 4868 CXXRecord->setHasTrivialCopyConstructor(false); 4869 if (!RDecl->hasTrivialCopyAssignment()) 4870 CXXRecord->setHasTrivialCopyAssignment(false); 4871 if (!RDecl->hasTrivialDestructor()) 4872 CXXRecord->setHasTrivialDestructor(false); 4873 4874 // C++ 9.5p1: An object of a class with a non-trivial 4875 // constructor, a non-trivial copy constructor, a non-trivial 4876 // destructor, or a non-trivial copy assignment operator 4877 // cannot be a member of a union, nor can an array of such 4878 // objects. 4879 // TODO: C++0x alters this restriction significantly. 4880 if (Record->isUnion()) { 4881 // We check for copy constructors before constructors 4882 // because otherwise we'll never get complaints about 4883 // copy constructors. 4884 4885 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4886 4887 CXXSpecialMember member; 4888 if (!RDecl->hasTrivialCopyConstructor()) 4889 member = CXXCopyConstructor; 4890 else if (!RDecl->hasTrivialConstructor()) 4891 member = CXXDefaultConstructor; 4892 else if (!RDecl->hasTrivialCopyAssignment()) 4893 member = CXXCopyAssignment; 4894 else if (!RDecl->hasTrivialDestructor()) 4895 member = CXXDestructor; 4896 else 4897 member = invalid; 4898 4899 if (member != invalid) { 4900 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4901 DiagnoseNontrivial(RT, member); 4902 NewFD->setInvalidDecl(); 4903 } 4904 } 4905 } 4906 } 4907 4908 // FIXME: We need to pass in the attributes given an AST 4909 // representation, not a parser representation. 4910 if (D) 4911 // FIXME: What to pass instead of TUScope? 4912 ProcessDeclAttributes(TUScope, NewFD, *D); 4913 4914 if (T.isObjCGCWeak()) 4915 Diag(Loc, diag::warn_attribute_weak_on_field); 4916 4917 NewFD->setAccess(AS); 4918 4919 // C++ [dcl.init.aggr]p1: 4920 // An aggregate is an array or a class (clause 9) with [...] no 4921 // private or protected non-static data members (clause 11). 4922 // A POD must be an aggregate. 4923 if (getLangOptions().CPlusPlus && 4924 (AS == AS_private || AS == AS_protected)) { 4925 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4926 CXXRecord->setAggregate(false); 4927 CXXRecord->setPOD(false); 4928 } 4929 4930 return NewFD; 4931} 4932 4933/// DiagnoseNontrivial - Given that a class has a non-trivial 4934/// special member, figure out why. 4935void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4936 QualType QT(T, 0U); 4937 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4938 4939 // Check whether the member was user-declared. 4940 switch (member) { 4941 case CXXDefaultConstructor: 4942 if (RD->hasUserDeclaredConstructor()) { 4943 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4944 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 4945 const FunctionDecl *body = 0; 4946 ci->getBody(body); 4947 if (!body || 4948 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 4949 SourceLocation CtorLoc = ci->getLocation(); 4950 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4951 return; 4952 } 4953 } 4954 4955 assert(0 && "found no user-declared constructors"); 4956 return; 4957 } 4958 break; 4959 4960 case CXXCopyConstructor: 4961 if (RD->hasUserDeclaredCopyConstructor()) { 4962 SourceLocation CtorLoc = 4963 RD->getCopyConstructor(Context, 0)->getLocation(); 4964 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4965 return; 4966 } 4967 break; 4968 4969 case CXXCopyAssignment: 4970 if (RD->hasUserDeclaredCopyAssignment()) { 4971 // FIXME: this should use the location of the copy 4972 // assignment, not the type. 4973 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4974 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4975 return; 4976 } 4977 break; 4978 4979 case CXXDestructor: 4980 if (RD->hasUserDeclaredDestructor()) { 4981 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4982 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4983 return; 4984 } 4985 break; 4986 } 4987 4988 typedef CXXRecordDecl::base_class_iterator base_iter; 4989 4990 // Virtual bases and members inhibit trivial copying/construction, 4991 // but not trivial destruction. 4992 if (member != CXXDestructor) { 4993 // Check for virtual bases. vbases includes indirect virtual bases, 4994 // so we just iterate through the direct bases. 4995 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4996 if (bi->isVirtual()) { 4997 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4998 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4999 return; 5000 } 5001 5002 // Check for virtual methods. 5003 typedef CXXRecordDecl::method_iterator meth_iter; 5004 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5005 ++mi) { 5006 if (mi->isVirtual()) { 5007 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5008 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5009 return; 5010 } 5011 } 5012 } 5013 5014 bool (CXXRecordDecl::*hasTrivial)() const; 5015 switch (member) { 5016 case CXXDefaultConstructor: 5017 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5018 case CXXCopyConstructor: 5019 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5020 case CXXCopyAssignment: 5021 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5022 case CXXDestructor: 5023 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5024 default: 5025 assert(0 && "unexpected special member"); return; 5026 } 5027 5028 // Check for nontrivial bases (and recurse). 5029 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5030 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5031 assert(BaseRT && "Don't know how to handle dependent bases"); 5032 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5033 if (!(BaseRecTy->*hasTrivial)()) { 5034 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5035 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5036 DiagnoseNontrivial(BaseRT, member); 5037 return; 5038 } 5039 } 5040 5041 // Check for nontrivial members (and recurse). 5042 typedef RecordDecl::field_iterator field_iter; 5043 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5044 ++fi) { 5045 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5046 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5047 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5048 5049 if (!(EltRD->*hasTrivial)()) { 5050 SourceLocation FLoc = (*fi)->getLocation(); 5051 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5052 DiagnoseNontrivial(EltRT, member); 5053 return; 5054 } 5055 } 5056 } 5057 5058 assert(0 && "found no explanation for non-trivial member"); 5059} 5060 5061/// TranslateIvarVisibility - Translate visibility from a token ID to an 5062/// AST enum value. 5063static ObjCIvarDecl::AccessControl 5064TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5065 switch (ivarVisibility) { 5066 default: assert(0 && "Unknown visitibility kind"); 5067 case tok::objc_private: return ObjCIvarDecl::Private; 5068 case tok::objc_public: return ObjCIvarDecl::Public; 5069 case tok::objc_protected: return ObjCIvarDecl::Protected; 5070 case tok::objc_package: return ObjCIvarDecl::Package; 5071 } 5072} 5073 5074/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5075/// in order to create an IvarDecl object for it. 5076Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5077 SourceLocation DeclStart, 5078 DeclPtrTy IntfDecl, 5079 Declarator &D, ExprTy *BitfieldWidth, 5080 tok::ObjCKeywordKind Visibility) { 5081 5082 IdentifierInfo *II = D.getIdentifier(); 5083 Expr *BitWidth = (Expr*)BitfieldWidth; 5084 SourceLocation Loc = DeclStart; 5085 if (II) Loc = D.getIdentifierLoc(); 5086 5087 // FIXME: Unnamed fields can be handled in various different ways, for 5088 // example, unnamed unions inject all members into the struct namespace! 5089 5090 DeclaratorInfo *DInfo = 0; 5091 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5092 5093 if (BitWidth) { 5094 // 6.7.2.1p3, 6.7.2.1p4 5095 if (VerifyBitField(Loc, II, T, BitWidth)) { 5096 D.setInvalidType(); 5097 DeleteExpr(BitWidth); 5098 BitWidth = 0; 5099 } 5100 } else { 5101 // Not a bitfield. 5102 5103 // validate II. 5104 5105 } 5106 5107 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5108 // than a variably modified type. 5109 if (T->isVariablyModifiedType()) { 5110 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5111 D.setInvalidType(); 5112 } 5113 5114 // Get the visibility (access control) for this ivar. 5115 ObjCIvarDecl::AccessControl ac = 5116 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5117 : ObjCIvarDecl::None; 5118 // Must set ivar's DeclContext to its enclosing interface. 5119 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5120 DeclContext *EnclosingContext; 5121 if (ObjCImplementationDecl *IMPDecl = 5122 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5123 // Case of ivar declared in an implementation. Context is that of its class. 5124 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5125 assert(IDecl && "No class- ActOnIvar"); 5126 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5127 } else 5128 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5129 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5130 5131 // Construct the decl. 5132 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5133 EnclosingContext, Loc, II, T, 5134 DInfo, ac, (Expr *)BitfieldWidth); 5135 5136 if (II) { 5137 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5138 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5139 && !isa<TagDecl>(PrevDecl)) { 5140 Diag(Loc, diag::err_duplicate_member) << II; 5141 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5142 NewID->setInvalidDecl(); 5143 } 5144 } 5145 5146 // Process attributes attached to the ivar. 5147 ProcessDeclAttributes(S, NewID, D); 5148 5149 if (D.isInvalidType()) 5150 NewID->setInvalidDecl(); 5151 5152 if (II) { 5153 // FIXME: When interfaces are DeclContexts, we'll need to add 5154 // these to the interface. 5155 S->AddDecl(DeclPtrTy::make(NewID)); 5156 IdResolver.AddDecl(NewID); 5157 } 5158 5159 return DeclPtrTy::make(NewID); 5160} 5161 5162void Sema::ActOnFields(Scope* S, 5163 SourceLocation RecLoc, DeclPtrTy RecDecl, 5164 DeclPtrTy *Fields, unsigned NumFields, 5165 SourceLocation LBrac, SourceLocation RBrac, 5166 AttributeList *Attr) { 5167 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5168 assert(EnclosingDecl && "missing record or interface decl"); 5169 5170 // If the decl this is being inserted into is invalid, then it may be a 5171 // redeclaration or some other bogus case. Don't try to add fields to it. 5172 if (EnclosingDecl->isInvalidDecl()) { 5173 // FIXME: Deallocate fields? 5174 return; 5175 } 5176 5177 5178 // Verify that all the fields are okay. 5179 unsigned NumNamedMembers = 0; 5180 llvm::SmallVector<FieldDecl*, 32> RecFields; 5181 5182 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5183 for (unsigned i = 0; i != NumFields; ++i) { 5184 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5185 5186 // Get the type for the field. 5187 Type *FDTy = FD->getType().getTypePtr(); 5188 5189 if (!FD->isAnonymousStructOrUnion()) { 5190 // Remember all fields written by the user. 5191 RecFields.push_back(FD); 5192 } 5193 5194 // If the field is already invalid for some reason, don't emit more 5195 // diagnostics about it. 5196 if (FD->isInvalidDecl()) 5197 continue; 5198 5199 // C99 6.7.2.1p2: 5200 // A structure or union shall not contain a member with 5201 // incomplete or function type (hence, a structure shall not 5202 // contain an instance of itself, but may contain a pointer to 5203 // an instance of itself), except that the last member of a 5204 // structure with more than one named member may have incomplete 5205 // array type; such a structure (and any union containing, 5206 // possibly recursively, a member that is such a structure) 5207 // shall not be a member of a structure or an element of an 5208 // array. 5209 if (FDTy->isFunctionType()) { 5210 // Field declared as a function. 5211 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5212 << FD->getDeclName(); 5213 FD->setInvalidDecl(); 5214 EnclosingDecl->setInvalidDecl(); 5215 continue; 5216 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5217 Record && Record->isStruct()) { 5218 // Flexible array member. 5219 if (NumNamedMembers < 1) { 5220 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5221 << FD->getDeclName(); 5222 FD->setInvalidDecl(); 5223 EnclosingDecl->setInvalidDecl(); 5224 continue; 5225 } 5226 // Okay, we have a legal flexible array member at the end of the struct. 5227 if (Record) 5228 Record->setHasFlexibleArrayMember(true); 5229 } else if (!FDTy->isDependentType() && 5230 RequireCompleteType(FD->getLocation(), FD->getType(), 5231 diag::err_field_incomplete)) { 5232 // Incomplete type 5233 FD->setInvalidDecl(); 5234 EnclosingDecl->setInvalidDecl(); 5235 continue; 5236 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5237 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5238 // If this is a member of a union, then entire union becomes "flexible". 5239 if (Record && Record->isUnion()) { 5240 Record->setHasFlexibleArrayMember(true); 5241 } else { 5242 // If this is a struct/class and this is not the last element, reject 5243 // it. Note that GCC supports variable sized arrays in the middle of 5244 // structures. 5245 if (i != NumFields-1) 5246 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5247 << FD->getDeclName() << FD->getType(); 5248 else { 5249 // We support flexible arrays at the end of structs in 5250 // other structs as an extension. 5251 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5252 << FD->getDeclName(); 5253 if (Record) 5254 Record->setHasFlexibleArrayMember(true); 5255 } 5256 } 5257 } 5258 if (Record && FDTTy->getDecl()->hasObjectMember()) 5259 Record->setHasObjectMember(true); 5260 } else if (FDTy->isObjCInterfaceType()) { 5261 /// A field cannot be an Objective-c object 5262 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5263 FD->setInvalidDecl(); 5264 EnclosingDecl->setInvalidDecl(); 5265 continue; 5266 } else if (getLangOptions().ObjC1 && 5267 getLangOptions().getGCMode() != LangOptions::NonGC && 5268 Record && 5269 (FD->getType()->isObjCObjectPointerType() || 5270 FD->getType().isObjCGCStrong())) 5271 Record->setHasObjectMember(true); 5272 // Keep track of the number of named members. 5273 if (FD->getIdentifier()) 5274 ++NumNamedMembers; 5275 } 5276 5277 // Okay, we successfully defined 'Record'. 5278 if (Record) { 5279 Record->completeDefinition(Context); 5280 } else { 5281 ObjCIvarDecl **ClsFields = 5282 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5283 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5284 ID->setIVarList(ClsFields, RecFields.size(), Context); 5285 ID->setLocEnd(RBrac); 5286 // Add ivar's to class's DeclContext. 5287 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5288 ClsFields[i]->setLexicalDeclContext(ID); 5289 ID->addDecl(ClsFields[i]); 5290 } 5291 // Must enforce the rule that ivars in the base classes may not be 5292 // duplicates. 5293 if (ID->getSuperClass()) { 5294 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5295 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5296 ObjCIvarDecl* Ivar = (*IVI); 5297 5298 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5299 ObjCIvarDecl* prevIvar = 5300 ID->getSuperClass()->lookupInstanceVariable(II); 5301 if (prevIvar) { 5302 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5303 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5304 } 5305 } 5306 } 5307 } 5308 } else if (ObjCImplementationDecl *IMPDecl = 5309 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5310 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5311 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5312 // Ivar declared in @implementation never belongs to the implementation. 5313 // Only it is in implementation's lexical context. 5314 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5315 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5316 } 5317 } 5318 5319 if (Attr) 5320 ProcessDeclAttributeList(S, Record, Attr); 5321} 5322 5323EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5324 EnumConstantDecl *LastEnumConst, 5325 SourceLocation IdLoc, 5326 IdentifierInfo *Id, 5327 ExprArg val) { 5328 Expr *Val = (Expr *)val.get(); 5329 5330 llvm::APSInt EnumVal(32); 5331 QualType EltTy; 5332 if (Val && !Val->isTypeDependent()) { 5333 // Make sure to promote the operand type to int. 5334 UsualUnaryConversions(Val); 5335 if (Val != val.get()) { 5336 val.release(); 5337 val = Val; 5338 } 5339 5340 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5341 SourceLocation ExpLoc; 5342 if (!Val->isValueDependent() && 5343 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5344 Val = 0; 5345 } else { 5346 EltTy = Val->getType(); 5347 } 5348 } 5349 5350 if (!Val) { 5351 if (LastEnumConst) { 5352 // Assign the last value + 1. 5353 EnumVal = LastEnumConst->getInitVal(); 5354 ++EnumVal; 5355 5356 // Check for overflow on increment. 5357 if (EnumVal < LastEnumConst->getInitVal()) 5358 Diag(IdLoc, diag::warn_enum_value_overflow); 5359 5360 EltTy = LastEnumConst->getType(); 5361 } else { 5362 // First value, set to zero. 5363 EltTy = Context.IntTy; 5364 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5365 } 5366 } 5367 5368 val.release(); 5369 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5370 Val, EnumVal); 5371} 5372 5373 5374Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5375 DeclPtrTy lastEnumConst, 5376 SourceLocation IdLoc, 5377 IdentifierInfo *Id, 5378 SourceLocation EqualLoc, ExprTy *val) { 5379 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5380 EnumConstantDecl *LastEnumConst = 5381 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5382 Expr *Val = static_cast<Expr*>(val); 5383 5384 // The scope passed in may not be a decl scope. Zip up the scope tree until 5385 // we find one that is. 5386 S = getNonFieldDeclScope(S); 5387 5388 // Verify that there isn't already something declared with this name in this 5389 // scope. 5390 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5391 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5392 // Maybe we will complain about the shadowed template parameter. 5393 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5394 // Just pretend that we didn't see the previous declaration. 5395 PrevDecl = 0; 5396 } 5397 5398 if (PrevDecl) { 5399 // When in C++, we may get a TagDecl with the same name; in this case the 5400 // enum constant will 'hide' the tag. 5401 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5402 "Received TagDecl when not in C++!"); 5403 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5404 if (isa<EnumConstantDecl>(PrevDecl)) 5405 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5406 else 5407 Diag(IdLoc, diag::err_redefinition) << Id; 5408 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5409 if (Val) Val->Destroy(Context); 5410 return DeclPtrTy(); 5411 } 5412 } 5413 5414 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5415 IdLoc, Id, Owned(Val)); 5416 5417 // Register this decl in the current scope stack. 5418 if (New) 5419 PushOnScopeChains(New, S); 5420 5421 return DeclPtrTy::make(New); 5422} 5423 5424void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5425 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5426 DeclPtrTy *Elements, unsigned NumElements, 5427 Scope *S, AttributeList *Attr) { 5428 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5429 QualType EnumType = Context.getTypeDeclType(Enum); 5430 5431 if (Attr) 5432 ProcessDeclAttributeList(S, Enum, Attr); 5433 5434 // TODO: If the result value doesn't fit in an int, it must be a long or long 5435 // long value. ISO C does not support this, but GCC does as an extension, 5436 // emit a warning. 5437 unsigned IntWidth = Context.Target.getIntWidth(); 5438 unsigned CharWidth = Context.Target.getCharWidth(); 5439 unsigned ShortWidth = Context.Target.getShortWidth(); 5440 5441 // Verify that all the values are okay, compute the size of the values, and 5442 // reverse the list. 5443 unsigned NumNegativeBits = 0; 5444 unsigned NumPositiveBits = 0; 5445 5446 // Keep track of whether all elements have type int. 5447 bool AllElementsInt = true; 5448 5449 for (unsigned i = 0; i != NumElements; ++i) { 5450 EnumConstantDecl *ECD = 5451 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5452 if (!ECD) continue; // Already issued a diagnostic. 5453 5454 // If the enum value doesn't fit in an int, emit an extension warning. 5455 const llvm::APSInt &InitVal = ECD->getInitVal(); 5456 assert(InitVal.getBitWidth() >= IntWidth && 5457 "Should have promoted value to int"); 5458 if (InitVal.getBitWidth() > IntWidth) { 5459 llvm::APSInt V(InitVal); 5460 V.trunc(IntWidth); 5461 V.extend(InitVal.getBitWidth()); 5462 if (V != InitVal) 5463 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5464 << InitVal.toString(10); 5465 } 5466 5467 // Keep track of the size of positive and negative values. 5468 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5469 NumPositiveBits = std::max(NumPositiveBits, 5470 (unsigned)InitVal.getActiveBits()); 5471 else 5472 NumNegativeBits = std::max(NumNegativeBits, 5473 (unsigned)InitVal.getMinSignedBits()); 5474 5475 // Keep track of whether every enum element has type int (very commmon). 5476 if (AllElementsInt) 5477 AllElementsInt = ECD->getType() == Context.IntTy; 5478 } 5479 5480 // Figure out the type that should be used for this enum. 5481 // FIXME: Support -fshort-enums. 5482 QualType BestType; 5483 unsigned BestWidth; 5484 5485 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5486 5487 if (NumNegativeBits) { 5488 // If there is a negative value, figure out the smallest integer type (of 5489 // int/long/longlong) that fits. 5490 // If it's packed, check also if it fits a char or a short. 5491 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5492 BestType = Context.SignedCharTy; 5493 BestWidth = CharWidth; 5494 } else if (Packed && NumNegativeBits <= ShortWidth && 5495 NumPositiveBits < ShortWidth) { 5496 BestType = Context.ShortTy; 5497 BestWidth = ShortWidth; 5498 } 5499 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5500 BestType = Context.IntTy; 5501 BestWidth = IntWidth; 5502 } else { 5503 BestWidth = Context.Target.getLongWidth(); 5504 5505 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5506 BestType = Context.LongTy; 5507 else { 5508 BestWidth = Context.Target.getLongLongWidth(); 5509 5510 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5511 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5512 BestType = Context.LongLongTy; 5513 } 5514 } 5515 } else { 5516 // If there is no negative value, figure out which of uint, ulong, ulonglong 5517 // fits. 5518 // If it's packed, check also if it fits a char or a short. 5519 if (Packed && NumPositiveBits <= CharWidth) { 5520 BestType = Context.UnsignedCharTy; 5521 BestWidth = CharWidth; 5522 } else if (Packed && NumPositiveBits <= ShortWidth) { 5523 BestType = Context.UnsignedShortTy; 5524 BestWidth = ShortWidth; 5525 } 5526 else if (NumPositiveBits <= IntWidth) { 5527 BestType = Context.UnsignedIntTy; 5528 BestWidth = IntWidth; 5529 } else if (NumPositiveBits <= 5530 (BestWidth = Context.Target.getLongWidth())) { 5531 BestType = Context.UnsignedLongTy; 5532 } else { 5533 BestWidth = Context.Target.getLongLongWidth(); 5534 assert(NumPositiveBits <= BestWidth && 5535 "How could an initializer get larger than ULL?"); 5536 BestType = Context.UnsignedLongLongTy; 5537 } 5538 } 5539 5540 // Loop over all of the enumerator constants, changing their types to match 5541 // the type of the enum if needed. 5542 for (unsigned i = 0; i != NumElements; ++i) { 5543 EnumConstantDecl *ECD = 5544 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5545 if (!ECD) continue; // Already issued a diagnostic. 5546 5547 // Standard C says the enumerators have int type, but we allow, as an 5548 // extension, the enumerators to be larger than int size. If each 5549 // enumerator value fits in an int, type it as an int, otherwise type it the 5550 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5551 // that X has type 'int', not 'unsigned'. 5552 if (ECD->getType() == Context.IntTy) { 5553 // Make sure the init value is signed. 5554 llvm::APSInt IV = ECD->getInitVal(); 5555 IV.setIsSigned(true); 5556 ECD->setInitVal(IV); 5557 5558 if (getLangOptions().CPlusPlus) 5559 // C++ [dcl.enum]p4: Following the closing brace of an 5560 // enum-specifier, each enumerator has the type of its 5561 // enumeration. 5562 ECD->setType(EnumType); 5563 continue; // Already int type. 5564 } 5565 5566 // Determine whether the value fits into an int. 5567 llvm::APSInt InitVal = ECD->getInitVal(); 5568 bool FitsInInt; 5569 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5570 FitsInInt = InitVal.getActiveBits() < IntWidth; 5571 else 5572 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5573 5574 // If it fits into an integer type, force it. Otherwise force it to match 5575 // the enum decl type. 5576 QualType NewTy; 5577 unsigned NewWidth; 5578 bool NewSign; 5579 if (FitsInInt) { 5580 NewTy = Context.IntTy; 5581 NewWidth = IntWidth; 5582 NewSign = true; 5583 } else if (ECD->getType() == BestType) { 5584 // Already the right type! 5585 if (getLangOptions().CPlusPlus) 5586 // C++ [dcl.enum]p4: Following the closing brace of an 5587 // enum-specifier, each enumerator has the type of its 5588 // enumeration. 5589 ECD->setType(EnumType); 5590 continue; 5591 } else { 5592 NewTy = BestType; 5593 NewWidth = BestWidth; 5594 NewSign = BestType->isSignedIntegerType(); 5595 } 5596 5597 // Adjust the APSInt value. 5598 InitVal.extOrTrunc(NewWidth); 5599 InitVal.setIsSigned(NewSign); 5600 ECD->setInitVal(InitVal); 5601 5602 // Adjust the Expr initializer and type. 5603 if (ECD->getInitExpr()) 5604 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5605 CastExpr::CK_IntegralCast, 5606 ECD->getInitExpr(), 5607 /*isLvalue=*/false)); 5608 if (getLangOptions().CPlusPlus) 5609 // C++ [dcl.enum]p4: Following the closing brace of an 5610 // enum-specifier, each enumerator has the type of its 5611 // enumeration. 5612 ECD->setType(EnumType); 5613 else 5614 ECD->setType(NewTy); 5615 } 5616 5617 Enum->completeDefinition(Context, BestType); 5618} 5619 5620Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5621 ExprArg expr) { 5622 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5623 5624 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5625 Loc, AsmString); 5626 CurContext->addDecl(New); 5627 return DeclPtrTy::make(New); 5628} 5629 5630void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5631 SourceLocation PragmaLoc, 5632 SourceLocation NameLoc) { 5633 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5634 5635 if (PrevDecl) { 5636 PrevDecl->addAttr(::new (Context) WeakAttr()); 5637 } else { 5638 (void)WeakUndeclaredIdentifiers.insert( 5639 std::pair<IdentifierInfo*,WeakInfo> 5640 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5641 } 5642} 5643 5644void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5645 IdentifierInfo* AliasName, 5646 SourceLocation PragmaLoc, 5647 SourceLocation NameLoc, 5648 SourceLocation AliasNameLoc) { 5649 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5650 WeakInfo W = WeakInfo(Name, NameLoc); 5651 5652 if (PrevDecl) { 5653 if (!PrevDecl->hasAttr<AliasAttr>()) 5654 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5655 DeclApplyPragmaWeak(TUScope, ND, W); 5656 } else { 5657 (void)WeakUndeclaredIdentifiers.insert( 5658 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5659 } 5660} 5661