SemaDecl.cpp revision 6675586c70945fdd71911d96f83324788b93edd4
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 "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/Analysis/CFG.h" 21#include "clang/AST/CXXInheritance.h" 22#include "clang/AST/DeclObjC.h" 23#include "clang/AST/DeclTemplate.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/StmtCXX.h" 26#include "clang/AST/StmtObjC.h" 27#include "clang/Parse/DeclSpec.h" 28#include "clang/Parse/ParseDiagnostic.h" 29#include "clang/Parse/Template.h" 30#include "clang/Basic/PartialDiagnostic.h" 31#include "clang/Basic/SourceManager.h" 32#include "clang/Basic/TargetInfo.h" 33// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 34#include "clang/Lex/Preprocessor.h" 35#include "clang/Lex/HeaderSearch.h" 36#include "llvm/ADT/BitVector.h" 37#include "llvm/ADT/STLExtras.h" 38#include "llvm/ADT/Triple.h" 39#include <algorithm> 40#include <cstring> 41#include <functional> 42#include <queue> 43using namespace clang; 44 45/// getDeclName - Return a pretty name for the specified decl if possible, or 46/// an empty string if not. This is used for pretty crash reporting. 47std::string Sema::getDeclName(DeclPtrTy d) { 48 Decl *D = d.getAs<Decl>(); 49 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 50 return DN->getQualifiedNameAsString(); 51 return ""; 52} 53 54Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 55 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 56} 57 58/// \brief If the identifier refers to a type name within this scope, 59/// return the declaration of that type. 60/// 61/// This routine performs ordinary name lookup of the identifier II 62/// within the given scope, with optional C++ scope specifier SS, to 63/// determine whether the name refers to a type. If so, returns an 64/// opaque pointer (actually a QualType) corresponding to that 65/// type. Otherwise, returns NULL. 66/// 67/// If name lookup results in an ambiguity, this routine will complain 68/// and then return NULL. 69Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 70 Scope *S, const CXXScopeSpec *SS, 71 bool isClassName, 72 TypeTy *ObjectTypePtr) { 73 // Determine where we will perform name lookup. 74 DeclContext *LookupCtx = 0; 75 if (ObjectTypePtr) { 76 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 77 if (ObjectType->isRecordType()) 78 LookupCtx = computeDeclContext(ObjectType); 79 } else if (SS && SS->isSet()) { 80 LookupCtx = computeDeclContext(*SS, false); 81 82 if (!LookupCtx) { 83 if (isDependentScopeSpecifier(*SS)) { 84 // C++ [temp.res]p3: 85 // A qualified-id that refers to a type and in which the 86 // nested-name-specifier depends on a template-parameter (14.6.2) 87 // shall be prefixed by the keyword typename to indicate that the 88 // qualified-id denotes a type, forming an 89 // elaborated-type-specifier (7.1.5.3). 90 // 91 // We therefore do not perform any name lookup if the result would 92 // refer to a member of an unknown specialization. 93 if (!isClassName) 94 return 0; 95 96 // We know from the grammar that this name refers to a type, so build a 97 // TypenameType node to describe the type. 98 // FIXME: Record somewhere that this TypenameType node has no "typename" 99 // keyword associated with it. 100 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 101 II, SS->getRange()).getAsOpaquePtr(); 102 } 103 104 return 0; 105 } 106 107 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 108 return 0; 109 } 110 111 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 112 // lookup for class-names. 113 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 114 LookupOrdinaryName; 115 LookupResult Result(*this, &II, NameLoc, Kind); 116 if (LookupCtx) { 117 // Perform "qualified" name lookup into the declaration context we 118 // computed, which is either the type of the base of a member access 119 // expression or the declaration context associated with a prior 120 // nested-name-specifier. 121 LookupQualifiedName(Result, LookupCtx); 122 123 if (ObjectTypePtr && Result.empty()) { 124 // C++ [basic.lookup.classref]p3: 125 // If the unqualified-id is ~type-name, the type-name is looked up 126 // in the context of the entire postfix-expression. If the type T of 127 // the object expression is of a class type C, the type-name is also 128 // looked up in the scope of class C. At least one of the lookups shall 129 // find a name that refers to (possibly cv-qualified) T. 130 LookupName(Result, S); 131 } 132 } else { 133 // Perform unqualified name lookup. 134 LookupName(Result, S); 135 } 136 137 NamedDecl *IIDecl = 0; 138 switch (Result.getResultKind()) { 139 case LookupResult::NotFound: 140 case LookupResult::FoundOverloaded: 141 case LookupResult::FoundUnresolvedValue: 142 return 0; 143 144 case LookupResult::Ambiguous: 145 // Recover from type-hiding ambiguities by hiding the type. We'll 146 // do the lookup again when looking for an object, and we can 147 // diagnose the error then. If we don't do this, then the error 148 // about hiding the type will be immediately followed by an error 149 // that only makes sense if the identifier was treated like a type. 150 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 151 Result.suppressDiagnostics(); 152 return 0; 153 } 154 155 // Look to see if we have a type anywhere in the list of results. 156 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 157 Res != ResEnd; ++Res) { 158 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 159 if (!IIDecl || 160 (*Res)->getLocation().getRawEncoding() < 161 IIDecl->getLocation().getRawEncoding()) 162 IIDecl = *Res; 163 } 164 } 165 166 if (!IIDecl) { 167 // None of the entities we found is a type, so there is no way 168 // to even assume that the result is a type. In this case, don't 169 // complain about the ambiguity. The parser will either try to 170 // perform this lookup again (e.g., as an object name), which 171 // will produce the ambiguity, or will complain that it expected 172 // a type name. 173 Result.suppressDiagnostics(); 174 return 0; 175 } 176 177 // We found a type within the ambiguous lookup; diagnose the 178 // ambiguity and then return that type. This might be the right 179 // answer, or it might not be, but it suppresses any attempt to 180 // perform the name lookup again. 181 break; 182 183 case LookupResult::Found: 184 IIDecl = Result.getFoundDecl(); 185 break; 186 } 187 188 assert(IIDecl && "Didn't find decl"); 189 190 QualType T; 191 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 192 DiagnoseUseOfDecl(IIDecl, NameLoc); 193 194 // C++ [temp.local]p2: 195 // Within the scope of a class template specialization or 196 // partial specialization, when the injected-class-name is 197 // not followed by a <, it is equivalent to the 198 // injected-class-name followed by the template-argument s 199 // of the class template specialization or partial 200 // specialization enclosed in <>. 201 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 202 if (RD->isInjectedClassName()) 203 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 204 T = Template->getInjectedClassNameType(Context); 205 206 if (T.isNull()) 207 T = Context.getTypeDeclType(TD); 208 209 if (SS) 210 T = getQualifiedNameType(*SS, T); 211 212 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 213 T = Context.getObjCInterfaceType(IDecl); 214 } else if (UnresolvedUsingTypenameDecl *UUDecl = 215 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 216 // FIXME: preserve source structure information. 217 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 218 } else { 219 // If it's not plausibly a type, suppress diagnostics. 220 Result.suppressDiagnostics(); 221 return 0; 222 } 223 224 return T.getAsOpaquePtr(); 225} 226 227/// isTagName() - This method is called *for error recovery purposes only* 228/// to determine if the specified name is a valid tag name ("struct foo"). If 229/// so, this returns the TST for the tag corresponding to it (TST_enum, 230/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 231/// where the user forgot to specify the tag. 232DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 233 // Do a tag name lookup in this scope. 234 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 235 LookupName(R, S, false); 236 R.suppressDiagnostics(); 237 if (R.getResultKind() == LookupResult::Found) 238 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 239 switch (TD->getTagKind()) { 240 case TagDecl::TK_struct: return DeclSpec::TST_struct; 241 case TagDecl::TK_union: return DeclSpec::TST_union; 242 case TagDecl::TK_class: return DeclSpec::TST_class; 243 case TagDecl::TK_enum: return DeclSpec::TST_enum; 244 } 245 } 246 247 return DeclSpec::TST_unspecified; 248} 249 250bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 251 SourceLocation IILoc, 252 Scope *S, 253 const CXXScopeSpec *SS, 254 TypeTy *&SuggestedType) { 255 // We don't have anything to suggest (yet). 256 SuggestedType = 0; 257 258 // FIXME: Should we move the logic that tries to recover from a missing tag 259 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 260 261 if (!SS) 262 Diag(IILoc, diag::err_unknown_typename) << &II; 263 else if (DeclContext *DC = computeDeclContext(*SS, false)) 264 Diag(IILoc, diag::err_typename_nested_not_found) 265 << &II << DC << SS->getRange(); 266 else if (isDependentScopeSpecifier(*SS)) { 267 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 268 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 269 << SourceRange(SS->getRange().getBegin(), IILoc) 270 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 271 "typename "); 272 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 273 } else { 274 assert(SS && SS->isInvalid() && 275 "Invalid scope specifier has already been diagnosed"); 276 } 277 278 return true; 279} 280 281// Determines the context to return to after temporarily entering a 282// context. This depends in an unnecessarily complicated way on the 283// exact ordering of callbacks from the parser. 284DeclContext *Sema::getContainingDC(DeclContext *DC) { 285 286 // Functions defined inline within classes aren't parsed until we've 287 // finished parsing the top-level class, so the top-level class is 288 // the context we'll need to return to. 289 if (isa<FunctionDecl>(DC)) { 290 DC = DC->getLexicalParent(); 291 292 // A function not defined within a class will always return to its 293 // lexical context. 294 if (!isa<CXXRecordDecl>(DC)) 295 return DC; 296 297 // A C++ inline method/friend is parsed *after* the topmost class 298 // it was declared in is fully parsed ("complete"); the topmost 299 // class is the context we need to return to. 300 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 301 DC = RD; 302 303 // Return the declaration context of the topmost class the inline method is 304 // declared in. 305 return DC; 306 } 307 308 if (isa<ObjCMethodDecl>(DC)) 309 return Context.getTranslationUnitDecl(); 310 311 return DC->getLexicalParent(); 312} 313 314void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 315 assert(getContainingDC(DC) == CurContext && 316 "The next DeclContext should be lexically contained in the current one."); 317 CurContext = DC; 318 S->setEntity(DC); 319} 320 321void Sema::PopDeclContext() { 322 assert(CurContext && "DeclContext imbalance!"); 323 324 CurContext = getContainingDC(CurContext); 325} 326 327/// EnterDeclaratorContext - Used when we must lookup names in the context 328/// of a declarator's nested name specifier. 329/// 330void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 331 // C++0x [basic.lookup.unqual]p13: 332 // A name used in the definition of a static data member of class 333 // X (after the qualified-id of the static member) is looked up as 334 // if the name was used in a member function of X. 335 // C++0x [basic.lookup.unqual]p14: 336 // If a variable member of a namespace is defined outside of the 337 // scope of its namespace then any name used in the definition of 338 // the variable member (after the declarator-id) is looked up as 339 // if the definition of the variable member occurred in its 340 // namespace. 341 // Both of these imply that we should push a scope whose context 342 // is the semantic context of the declaration. We can't use 343 // PushDeclContext here because that context is not necessarily 344 // lexically contained in the current context. Fortunately, 345 // the containing scope should have the appropriate information. 346 347 assert(!S->getEntity() && "scope already has entity"); 348 349#ifndef NDEBUG 350 Scope *Ancestor = S->getParent(); 351 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 352 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 353#endif 354 355 CurContext = DC; 356 S->setEntity(DC); 357} 358 359void Sema::ExitDeclaratorContext(Scope *S) { 360 assert(S->getEntity() == CurContext && "Context imbalance!"); 361 362 // Switch back to the lexical context. The safety of this is 363 // enforced by an assert in EnterDeclaratorContext. 364 Scope *Ancestor = S->getParent(); 365 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 366 CurContext = (DeclContext*) Ancestor->getEntity(); 367 368 // We don't need to do anything with the scope, which is going to 369 // disappear. 370} 371 372/// \brief Determine whether we allow overloading of the function 373/// PrevDecl with another declaration. 374/// 375/// This routine determines whether overloading is possible, not 376/// whether some new function is actually an overload. It will return 377/// true in C++ (where we can always provide overloads) or, as an 378/// extension, in C when the previous function is already an 379/// overloaded function declaration or has the "overloadable" 380/// attribute. 381static bool AllowOverloadingOfFunction(LookupResult &Previous, 382 ASTContext &Context) { 383 if (Context.getLangOptions().CPlusPlus) 384 return true; 385 386 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 387 return true; 388 389 return (Previous.getResultKind() == LookupResult::Found 390 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 391} 392 393/// Add this decl to the scope shadowed decl chains. 394void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 395 // Move up the scope chain until we find the nearest enclosing 396 // non-transparent context. The declaration will be introduced into this 397 // scope. 398 while (S->getEntity() && 399 ((DeclContext *)S->getEntity())->isTransparentContext()) 400 S = S->getParent(); 401 402 // Add scoped declarations into their context, so that they can be 403 // found later. Declarations without a context won't be inserted 404 // into any context. 405 if (AddToContext) 406 CurContext->addDecl(D); 407 408 // Out-of-line function and variable definitions should not be pushed into 409 // scope. 410 if ((isa<FunctionTemplateDecl>(D) && 411 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 412 (isa<FunctionDecl>(D) && 413 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 414 cast<FunctionDecl>(D)->isOutOfLine())) || 415 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 416 return; 417 418 // If this replaces anything in the current scope, 419 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 420 IEnd = IdResolver.end(); 421 for (; I != IEnd; ++I) { 422 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 423 S->RemoveDecl(DeclPtrTy::make(*I)); 424 IdResolver.RemoveDecl(*I); 425 426 // Should only need to replace one decl. 427 break; 428 } 429 } 430 431 S->AddDecl(DeclPtrTy::make(D)); 432 IdResolver.AddDecl(D); 433} 434 435bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 436 return IdResolver.isDeclInScope(D, Ctx, Context, S); 437} 438 439static bool isOutOfScopePreviousDeclaration(NamedDecl *, 440 DeclContext*, 441 ASTContext&); 442 443/// Filters out lookup results that don't fall within the given scope 444/// as determined by isDeclInScope. 445static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 446 DeclContext *Ctx, Scope *S, 447 bool ConsiderLinkage) { 448 LookupResult::Filter F = R.makeFilter(); 449 while (F.hasNext()) { 450 NamedDecl *D = F.next(); 451 452 if (SemaRef.isDeclInScope(D, Ctx, S)) 453 continue; 454 455 if (ConsiderLinkage && 456 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 457 continue; 458 459 F.erase(); 460 } 461 462 F.done(); 463} 464 465static bool isUsingDecl(NamedDecl *D) { 466 return isa<UsingShadowDecl>(D) || 467 isa<UnresolvedUsingTypenameDecl>(D) || 468 isa<UnresolvedUsingValueDecl>(D); 469} 470 471/// Removes using shadow declarations from the lookup results. 472static void RemoveUsingDecls(LookupResult &R) { 473 LookupResult::Filter F = R.makeFilter(); 474 while (F.hasNext()) 475 if (isUsingDecl(F.next())) 476 F.erase(); 477 478 F.done(); 479} 480 481static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 482 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 483 return false; 484 485 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 486 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 487 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 488 if (!RD->hasTrivialConstructor()) 489 return false; 490 if (!RD->hasTrivialDestructor()) 491 return false; 492 } 493 } 494 } 495 496 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 497 !isa<ImplicitParamDecl>(D) && 498 D->getDeclContext()->isFunctionOrMethod()); 499} 500 501void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 502 if (S->decl_empty()) return; 503 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 504 "Scope shouldn't contain decls!"); 505 506 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 507 I != E; ++I) { 508 Decl *TmpD = (*I).getAs<Decl>(); 509 assert(TmpD && "This decl didn't get pushed??"); 510 511 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 512 NamedDecl *D = cast<NamedDecl>(TmpD); 513 514 if (!D->getDeclName()) continue; 515 516 // Diagnose unused variables in this scope. 517 if (ShouldDiagnoseUnusedDecl(D)) 518 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 519 520 // Remove this name from our lexical scope. 521 IdResolver.RemoveDecl(D); 522 } 523} 524 525/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 526/// return 0 if one not found. 527ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 528 // The third "scope" argument is 0 since we aren't enabling lazy built-in 529 // creation from this context. 530 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 531 532 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 533} 534 535/// getNonFieldDeclScope - Retrieves the innermost scope, starting 536/// from S, where a non-field would be declared. This routine copes 537/// with the difference between C and C++ scoping rules in structs and 538/// unions. For example, the following code is well-formed in C but 539/// ill-formed in C++: 540/// @code 541/// struct S6 { 542/// enum { BAR } e; 543/// }; 544/// 545/// void test_S6() { 546/// struct S6 a; 547/// a.e = BAR; 548/// } 549/// @endcode 550/// For the declaration of BAR, this routine will return a different 551/// scope. The scope S will be the scope of the unnamed enumeration 552/// within S6. In C++, this routine will return the scope associated 553/// with S6, because the enumeration's scope is a transparent 554/// context but structures can contain non-field names. In C, this 555/// routine will return the translation unit scope, since the 556/// enumeration's scope is a transparent context and structures cannot 557/// contain non-field names. 558Scope *Sema::getNonFieldDeclScope(Scope *S) { 559 while (((S->getFlags() & Scope::DeclScope) == 0) || 560 (S->getEntity() && 561 ((DeclContext *)S->getEntity())->isTransparentContext()) || 562 (S->isClassScope() && !getLangOptions().CPlusPlus)) 563 S = S->getParent(); 564 return S; 565} 566 567void Sema::InitBuiltinVaListType() { 568 if (!Context.getBuiltinVaListType().isNull()) 569 return; 570 571 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 572 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 573 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 574 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 575} 576 577/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 578/// file scope. lazily create a decl for it. ForRedeclaration is true 579/// if we're creating this built-in in anticipation of redeclaring the 580/// built-in. 581NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 582 Scope *S, bool ForRedeclaration, 583 SourceLocation Loc) { 584 Builtin::ID BID = (Builtin::ID)bid; 585 586 if (Context.BuiltinInfo.hasVAListUse(BID)) 587 InitBuiltinVaListType(); 588 589 ASTContext::GetBuiltinTypeError Error; 590 QualType R = Context.GetBuiltinType(BID, Error); 591 switch (Error) { 592 case ASTContext::GE_None: 593 // Okay 594 break; 595 596 case ASTContext::GE_Missing_stdio: 597 if (ForRedeclaration) 598 Diag(Loc, diag::err_implicit_decl_requires_stdio) 599 << Context.BuiltinInfo.GetName(BID); 600 return 0; 601 602 case ASTContext::GE_Missing_setjmp: 603 if (ForRedeclaration) 604 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 605 << Context.BuiltinInfo.GetName(BID); 606 return 0; 607 } 608 609 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 610 Diag(Loc, diag::ext_implicit_lib_function_decl) 611 << Context.BuiltinInfo.GetName(BID) 612 << R; 613 if (Context.BuiltinInfo.getHeaderName(BID) && 614 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 615 != Diagnostic::Ignored) 616 Diag(Loc, diag::note_please_include_header) 617 << Context.BuiltinInfo.getHeaderName(BID) 618 << Context.BuiltinInfo.GetName(BID); 619 } 620 621 FunctionDecl *New = FunctionDecl::Create(Context, 622 Context.getTranslationUnitDecl(), 623 Loc, II, R, /*TInfo=*/0, 624 FunctionDecl::Extern, false, 625 /*hasPrototype=*/true); 626 New->setImplicit(); 627 628 // Create Decl objects for each parameter, adding them to the 629 // FunctionDecl. 630 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 631 llvm::SmallVector<ParmVarDecl*, 16> Params; 632 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 633 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 634 FT->getArgType(i), /*TInfo=*/0, 635 VarDecl::None, 0)); 636 New->setParams(Context, Params.data(), Params.size()); 637 } 638 639 AddKnownFunctionAttributes(New); 640 641 // TUScope is the translation-unit scope to insert this function into. 642 // FIXME: This is hideous. We need to teach PushOnScopeChains to 643 // relate Scopes to DeclContexts, and probably eliminate CurContext 644 // entirely, but we're not there yet. 645 DeclContext *SavedContext = CurContext; 646 CurContext = Context.getTranslationUnitDecl(); 647 PushOnScopeChains(New, TUScope); 648 CurContext = SavedContext; 649 return New; 650} 651 652/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 653/// same name and scope as a previous declaration 'Old'. Figure out 654/// how to resolve this situation, merging decls or emitting 655/// diagnostics as appropriate. If there was an error, set New to be invalid. 656/// 657void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 658 // If the new decl is known invalid already, don't bother doing any 659 // merging checks. 660 if (New->isInvalidDecl()) return; 661 662 // Allow multiple definitions for ObjC built-in typedefs. 663 // FIXME: Verify the underlying types are equivalent! 664 if (getLangOptions().ObjC1) { 665 const IdentifierInfo *TypeID = New->getIdentifier(); 666 switch (TypeID->getLength()) { 667 default: break; 668 case 2: 669 if (!TypeID->isStr("id")) 670 break; 671 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 672 // Install the built-in type for 'id', ignoring the current definition. 673 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 674 return; 675 case 5: 676 if (!TypeID->isStr("Class")) 677 break; 678 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 679 // Install the built-in type for 'Class', ignoring the current definition. 680 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 681 return; 682 case 3: 683 if (!TypeID->isStr("SEL")) 684 break; 685 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 686 // Install the built-in type for 'SEL', ignoring the current definition. 687 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 688 return; 689 case 8: 690 if (!TypeID->isStr("Protocol")) 691 break; 692 Context.setObjCProtoType(New->getUnderlyingType()); 693 return; 694 } 695 // Fall through - the typedef name was not a builtin type. 696 } 697 698 // Verify the old decl was also a type. 699 TypeDecl *Old = 0; 700 if (!OldDecls.isSingleResult() || 701 !(Old = dyn_cast<TypeDecl>(OldDecls.getFoundDecl()))) { 702 Diag(New->getLocation(), diag::err_redefinition_different_kind) 703 << New->getDeclName(); 704 705 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 706 if (OldD->getLocation().isValid()) 707 Diag(OldD->getLocation(), diag::note_previous_definition); 708 709 return New->setInvalidDecl(); 710 } 711 712 // If the old declaration is invalid, just give up here. 713 if (Old->isInvalidDecl()) 714 return New->setInvalidDecl(); 715 716 // Determine the "old" type we'll use for checking and diagnostics. 717 QualType OldType; 718 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 719 OldType = OldTypedef->getUnderlyingType(); 720 else 721 OldType = Context.getTypeDeclType(Old); 722 723 // If the typedef types are not identical, reject them in all languages and 724 // with any extensions enabled. 725 726 if (OldType != New->getUnderlyingType() && 727 Context.getCanonicalType(OldType) != 728 Context.getCanonicalType(New->getUnderlyingType())) { 729 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 730 << New->getUnderlyingType() << OldType; 731 if (Old->getLocation().isValid()) 732 Diag(Old->getLocation(), diag::note_previous_definition); 733 return New->setInvalidDecl(); 734 } 735 736 if (getLangOptions().Microsoft) 737 return; 738 739 // C++ [dcl.typedef]p2: 740 // In a given non-class scope, a typedef specifier can be used to 741 // redefine the name of any type declared in that scope to refer 742 // to the type to which it already refers. 743 if (getLangOptions().CPlusPlus) { 744 if (!isa<CXXRecordDecl>(CurContext)) 745 return; 746 Diag(New->getLocation(), diag::err_redefinition) 747 << New->getDeclName(); 748 Diag(Old->getLocation(), diag::note_previous_definition); 749 return New->setInvalidDecl(); 750 } 751 752 // If we have a redefinition of a typedef in C, emit a warning. This warning 753 // is normally mapped to an error, but can be controlled with 754 // -Wtypedef-redefinition. If either the original or the redefinition is 755 // in a system header, don't emit this for compatibility with GCC. 756 if (PP.getDiagnostics().getSuppressSystemWarnings() && 757 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 758 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 759 return; 760 761 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 762 << New->getDeclName(); 763 Diag(Old->getLocation(), diag::note_previous_definition); 764 return; 765} 766 767/// DeclhasAttr - returns true if decl Declaration already has the target 768/// attribute. 769static bool 770DeclHasAttr(const Decl *decl, const Attr *target) { 771 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 772 if (attr->getKind() == target->getKind()) 773 return true; 774 775 return false; 776} 777 778/// MergeAttributes - append attributes from the Old decl to the New one. 779static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 780 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 781 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 782 Attr *NewAttr = attr->clone(C); 783 NewAttr->setInherited(true); 784 New->addAttr(NewAttr); 785 } 786 } 787} 788 789/// Used in MergeFunctionDecl to keep track of function parameters in 790/// C. 791struct GNUCompatibleParamWarning { 792 ParmVarDecl *OldParm; 793 ParmVarDecl *NewParm; 794 QualType PromotedType; 795}; 796 797 798/// getSpecialMember - get the special member enum for a method. 799static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 800 const CXXMethodDecl *MD) { 801 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 802 if (Ctor->isDefaultConstructor()) 803 return Sema::CXXDefaultConstructor; 804 if (Ctor->isCopyConstructor()) 805 return Sema::CXXCopyConstructor; 806 } 807 808 if (isa<CXXDestructorDecl>(MD)) 809 return Sema::CXXDestructor; 810 811 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 812 return Sema::CXXCopyAssignment; 813} 814 815/// MergeFunctionDecl - We just parsed a function 'New' from 816/// declarator D which has the same name and scope as a previous 817/// declaration 'Old'. Figure out how to resolve this situation, 818/// merging decls or emitting diagnostics as appropriate. 819/// 820/// In C++, New and Old must be declarations that are not 821/// overloaded. Use IsOverload to determine whether New and Old are 822/// overloaded, and to select the Old declaration that New should be 823/// merged with. 824/// 825/// Returns true if there was an error, false otherwise. 826bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 827 // Verify the old decl was also a function. 828 FunctionDecl *Old = 0; 829 if (FunctionTemplateDecl *OldFunctionTemplate 830 = dyn_cast<FunctionTemplateDecl>(OldD)) 831 Old = OldFunctionTemplate->getTemplatedDecl(); 832 else 833 Old = dyn_cast<FunctionDecl>(OldD); 834 if (!Old) { 835 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 836 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 837 Diag(Shadow->getTargetDecl()->getLocation(), 838 diag::note_using_decl_target); 839 Diag(Shadow->getUsingDecl()->getLocation(), 840 diag::note_using_decl) << 0; 841 return true; 842 } 843 844 Diag(New->getLocation(), diag::err_redefinition_different_kind) 845 << New->getDeclName(); 846 Diag(OldD->getLocation(), diag::note_previous_definition); 847 return true; 848 } 849 850 // Determine whether the previous declaration was a definition, 851 // implicit declaration, or a declaration. 852 diag::kind PrevDiag; 853 if (Old->isThisDeclarationADefinition()) 854 PrevDiag = diag::note_previous_definition; 855 else if (Old->isImplicit()) 856 PrevDiag = diag::note_previous_implicit_declaration; 857 else 858 PrevDiag = diag::note_previous_declaration; 859 860 QualType OldQType = Context.getCanonicalType(Old->getType()); 861 QualType NewQType = Context.getCanonicalType(New->getType()); 862 863 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 864 New->getStorageClass() == FunctionDecl::Static && 865 Old->getStorageClass() != FunctionDecl::Static) { 866 Diag(New->getLocation(), diag::err_static_non_static) 867 << New; 868 Diag(Old->getLocation(), PrevDiag); 869 return true; 870 } 871 872 if (getLangOptions().CPlusPlus) { 873 // (C++98 13.1p2): 874 // Certain function declarations cannot be overloaded: 875 // -- Function declarations that differ only in the return type 876 // cannot be overloaded. 877 QualType OldReturnType 878 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 879 QualType NewReturnType 880 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 881 if (OldReturnType != NewReturnType) { 882 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 883 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 884 return true; 885 } 886 887 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 888 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 889 if (OldMethod && NewMethod) { 890 if (!NewMethod->getFriendObjectKind() && 891 NewMethod->getLexicalDeclContext()->isRecord()) { 892 // -- Member function declarations with the same name and the 893 // same parameter types cannot be overloaded if any of them 894 // is a static member function declaration. 895 if (OldMethod->isStatic() || NewMethod->isStatic()) { 896 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 897 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 898 return true; 899 } 900 901 // C++ [class.mem]p1: 902 // [...] A member shall not be declared twice in the 903 // member-specification, except that a nested class or member 904 // class template can be declared and then later defined. 905 unsigned NewDiag; 906 if (isa<CXXConstructorDecl>(OldMethod)) 907 NewDiag = diag::err_constructor_redeclared; 908 else if (isa<CXXDestructorDecl>(NewMethod)) 909 NewDiag = diag::err_destructor_redeclared; 910 else if (isa<CXXConversionDecl>(NewMethod)) 911 NewDiag = diag::err_conv_function_redeclared; 912 else 913 NewDiag = diag::err_member_redeclared; 914 915 Diag(New->getLocation(), NewDiag); 916 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 917 } else { 918 if (OldMethod->isImplicit()) { 919 Diag(NewMethod->getLocation(), 920 diag::err_definition_of_implicitly_declared_member) 921 << New << getSpecialMember(Context, OldMethod); 922 923 Diag(OldMethod->getLocation(), 924 diag::note_previous_implicit_declaration); 925 return true; 926 } 927 } 928 } 929 930 // (C++98 8.3.5p3): 931 // All declarations for a function shall agree exactly in both the 932 // return type and the parameter-type-list. 933 // attributes should be ignored when comparing. 934 if (Context.getNoReturnType(OldQType, false) == 935 Context.getNoReturnType(NewQType, false)) 936 return MergeCompatibleFunctionDecls(New, Old); 937 938 // Fall through for conflicting redeclarations and redefinitions. 939 } 940 941 // C: Function types need to be compatible, not identical. This handles 942 // duplicate function decls like "void f(int); void f(enum X);" properly. 943 if (!getLangOptions().CPlusPlus && 944 Context.typesAreCompatible(OldQType, NewQType)) { 945 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 946 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 947 const FunctionProtoType *OldProto = 0; 948 if (isa<FunctionNoProtoType>(NewFuncType) && 949 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 950 // The old declaration provided a function prototype, but the 951 // new declaration does not. Merge in the prototype. 952 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 953 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 954 OldProto->arg_type_end()); 955 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 956 ParamTypes.data(), ParamTypes.size(), 957 OldProto->isVariadic(), 958 OldProto->getTypeQuals()); 959 New->setType(NewQType); 960 New->setHasInheritedPrototype(); 961 962 // Synthesize a parameter for each argument type. 963 llvm::SmallVector<ParmVarDecl*, 16> Params; 964 for (FunctionProtoType::arg_type_iterator 965 ParamType = OldProto->arg_type_begin(), 966 ParamEnd = OldProto->arg_type_end(); 967 ParamType != ParamEnd; ++ParamType) { 968 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 969 SourceLocation(), 0, 970 *ParamType, /*TInfo=*/0, 971 VarDecl::None, 0); 972 Param->setImplicit(); 973 Params.push_back(Param); 974 } 975 976 New->setParams(Context, Params.data(), Params.size()); 977 } 978 979 return MergeCompatibleFunctionDecls(New, Old); 980 } 981 982 // GNU C permits a K&R definition to follow a prototype declaration 983 // if the declared types of the parameters in the K&R definition 984 // match the types in the prototype declaration, even when the 985 // promoted types of the parameters from the K&R definition differ 986 // from the types in the prototype. GCC then keeps the types from 987 // the prototype. 988 // 989 // If a variadic prototype is followed by a non-variadic K&R definition, 990 // the K&R definition becomes variadic. This is sort of an edge case, but 991 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 992 // C99 6.9.1p8. 993 if (!getLangOptions().CPlusPlus && 994 Old->hasPrototype() && !New->hasPrototype() && 995 New->getType()->getAs<FunctionProtoType>() && 996 Old->getNumParams() == New->getNumParams()) { 997 llvm::SmallVector<QualType, 16> ArgTypes; 998 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 999 const FunctionProtoType *OldProto 1000 = Old->getType()->getAs<FunctionProtoType>(); 1001 const FunctionProtoType *NewProto 1002 = New->getType()->getAs<FunctionProtoType>(); 1003 1004 // Determine whether this is the GNU C extension. 1005 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1006 NewProto->getResultType()); 1007 bool LooseCompatible = !MergedReturn.isNull(); 1008 for (unsigned Idx = 0, End = Old->getNumParams(); 1009 LooseCompatible && Idx != End; ++Idx) { 1010 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1011 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1012 if (Context.typesAreCompatible(OldParm->getType(), 1013 NewProto->getArgType(Idx))) { 1014 ArgTypes.push_back(NewParm->getType()); 1015 } else if (Context.typesAreCompatible(OldParm->getType(), 1016 NewParm->getType())) { 1017 GNUCompatibleParamWarning Warn 1018 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1019 Warnings.push_back(Warn); 1020 ArgTypes.push_back(NewParm->getType()); 1021 } else 1022 LooseCompatible = false; 1023 } 1024 1025 if (LooseCompatible) { 1026 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1027 Diag(Warnings[Warn].NewParm->getLocation(), 1028 diag::ext_param_promoted_not_compatible_with_prototype) 1029 << Warnings[Warn].PromotedType 1030 << Warnings[Warn].OldParm->getType(); 1031 Diag(Warnings[Warn].OldParm->getLocation(), 1032 diag::note_previous_declaration); 1033 } 1034 1035 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1036 ArgTypes.size(), 1037 OldProto->isVariadic(), 0)); 1038 return MergeCompatibleFunctionDecls(New, Old); 1039 } 1040 1041 // Fall through to diagnose conflicting types. 1042 } 1043 1044 // A function that has already been declared has been redeclared or defined 1045 // with a different type- show appropriate diagnostic 1046 if (unsigned BuiltinID = Old->getBuiltinID()) { 1047 // The user has declared a builtin function with an incompatible 1048 // signature. 1049 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1050 // The function the user is redeclaring is a library-defined 1051 // function like 'malloc' or 'printf'. Warn about the 1052 // redeclaration, then pretend that we don't know about this 1053 // library built-in. 1054 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1055 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1056 << Old << Old->getType(); 1057 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1058 Old->setInvalidDecl(); 1059 return false; 1060 } 1061 1062 PrevDiag = diag::note_previous_builtin_declaration; 1063 } 1064 1065 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1066 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1067 return true; 1068} 1069 1070/// \brief Completes the merge of two function declarations that are 1071/// known to be compatible. 1072/// 1073/// This routine handles the merging of attributes and other 1074/// properties of function declarations form the old declaration to 1075/// the new declaration, once we know that New is in fact a 1076/// redeclaration of Old. 1077/// 1078/// \returns false 1079bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1080 // Merge the attributes 1081 MergeAttributes(New, Old, Context); 1082 1083 // Merge the storage class. 1084 if (Old->getStorageClass() != FunctionDecl::Extern && 1085 Old->getStorageClass() != FunctionDecl::None) 1086 New->setStorageClass(Old->getStorageClass()); 1087 1088 // Merge "pure" flag. 1089 if (Old->isPure()) 1090 New->setPure(); 1091 1092 // Merge the "deleted" flag. 1093 if (Old->isDeleted()) 1094 New->setDeleted(); 1095 1096 if (getLangOptions().CPlusPlus) 1097 return MergeCXXFunctionDecl(New, Old); 1098 1099 return false; 1100} 1101 1102/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1103/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1104/// situation, merging decls or emitting diagnostics as appropriate. 1105/// 1106/// Tentative definition rules (C99 6.9.2p2) are checked by 1107/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1108/// definitions here, since the initializer hasn't been attached. 1109/// 1110void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1111 // If the new decl is already invalid, don't do any other checking. 1112 if (New->isInvalidDecl()) 1113 return; 1114 1115 // Verify the old decl was also a variable. 1116 VarDecl *Old = 0; 1117 if (!Previous.isSingleResult() || 1118 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1119 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1120 << New->getDeclName(); 1121 Diag(Previous.getRepresentativeDecl()->getLocation(), 1122 diag::note_previous_definition); 1123 return New->setInvalidDecl(); 1124 } 1125 1126 MergeAttributes(New, Old, Context); 1127 1128 // Merge the types 1129 QualType MergedT; 1130 if (getLangOptions().CPlusPlus) { 1131 if (Context.hasSameType(New->getType(), Old->getType())) 1132 MergedT = New->getType(); 1133 // C++ [basic.link]p10: 1134 // [...] the types specified by all declarations referring to a given 1135 // object or function shall be identical, except that declarations for an 1136 // array object can specify array types that differ by the presence or 1137 // absence of a major array bound (8.3.4). 1138 else if (Old->getType()->isIncompleteArrayType() && 1139 New->getType()->isArrayType()) { 1140 CanQual<ArrayType> OldArray 1141 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1142 CanQual<ArrayType> NewArray 1143 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1144 if (OldArray->getElementType() == NewArray->getElementType()) 1145 MergedT = New->getType(); 1146 } else if (Old->getType()->isArrayType() && 1147 New->getType()->isIncompleteArrayType()) { 1148 CanQual<ArrayType> OldArray 1149 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1150 CanQual<ArrayType> NewArray 1151 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1152 if (OldArray->getElementType() == NewArray->getElementType()) 1153 MergedT = Old->getType(); 1154 } 1155 } else { 1156 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1157 } 1158 if (MergedT.isNull()) { 1159 Diag(New->getLocation(), diag::err_redefinition_different_type) 1160 << New->getDeclName(); 1161 Diag(Old->getLocation(), diag::note_previous_definition); 1162 return New->setInvalidDecl(); 1163 } 1164 New->setType(MergedT); 1165 1166 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1167 if (New->getStorageClass() == VarDecl::Static && 1168 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1169 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1170 Diag(Old->getLocation(), diag::note_previous_definition); 1171 return New->setInvalidDecl(); 1172 } 1173 // C99 6.2.2p4: 1174 // For an identifier declared with the storage-class specifier 1175 // extern in a scope in which a prior declaration of that 1176 // identifier is visible,23) if the prior declaration specifies 1177 // internal or external linkage, the linkage of the identifier at 1178 // the later declaration is the same as the linkage specified at 1179 // the prior declaration. If no prior declaration is visible, or 1180 // if the prior declaration specifies no linkage, then the 1181 // identifier has external linkage. 1182 if (New->hasExternalStorage() && Old->hasLinkage()) 1183 /* Okay */; 1184 else if (New->getStorageClass() != VarDecl::Static && 1185 Old->getStorageClass() == VarDecl::Static) { 1186 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1187 Diag(Old->getLocation(), diag::note_previous_definition); 1188 return New->setInvalidDecl(); 1189 } 1190 1191 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1192 1193 // FIXME: The test for external storage here seems wrong? We still 1194 // need to check for mismatches. 1195 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1196 // Don't complain about out-of-line definitions of static members. 1197 !(Old->getLexicalDeclContext()->isRecord() && 1198 !New->getLexicalDeclContext()->isRecord())) { 1199 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1200 Diag(Old->getLocation(), diag::note_previous_definition); 1201 return New->setInvalidDecl(); 1202 } 1203 1204 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1205 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1206 Diag(Old->getLocation(), diag::note_previous_definition); 1207 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1208 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1209 Diag(Old->getLocation(), diag::note_previous_definition); 1210 } 1211 1212 // Keep a chain of previous declarations. 1213 New->setPreviousDeclaration(Old); 1214} 1215 1216/// CheckFallThrough - Check that we don't fall off the end of a 1217/// Statement that should return a value. 1218/// 1219/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1220/// MaybeFallThrough iff we might or might not fall off the end, 1221/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1222/// return. We assume NeverFallThrough iff we never fall off the end of the 1223/// statement but we may return. We assume that functions not marked noreturn 1224/// will return. 1225Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1226 // FIXME: Eventually share this CFG object when we have other warnings based 1227 // of the CFG. This can be done using AnalysisContext. 1228 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1229 1230 // FIXME: They should never return 0, fix that, delete this code. 1231 if (cfg == 0) 1232 // FIXME: This should be NeverFallThrough 1233 return NeverFallThroughOrReturn; 1234 // The CFG leaves in dead things, and we don't want to dead code paths to 1235 // confuse us, so we mark all live things first. 1236 std::queue<CFGBlock*> workq; 1237 llvm::BitVector live(cfg->getNumBlockIDs()); 1238 // Prep work queue 1239 workq.push(&cfg->getEntry()); 1240 // Solve 1241 while (!workq.empty()) { 1242 CFGBlock *item = workq.front(); 1243 workq.pop(); 1244 live.set(item->getBlockID()); 1245 for (CFGBlock::succ_iterator I=item->succ_begin(), 1246 E=item->succ_end(); 1247 I != E; 1248 ++I) { 1249 if ((*I) && !live[(*I)->getBlockID()]) { 1250 live.set((*I)->getBlockID()); 1251 workq.push(*I); 1252 } 1253 } 1254 } 1255 1256 // Now we know what is live, we check the live precessors of the exit block 1257 // and look for fall through paths, being careful to ignore normal returns, 1258 // and exceptional paths. 1259 bool HasLiveReturn = false; 1260 bool HasFakeEdge = false; 1261 bool HasPlainEdge = false; 1262 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1263 E = cfg->getExit().pred_end(); 1264 I != E; 1265 ++I) { 1266 CFGBlock& B = **I; 1267 if (!live[B.getBlockID()]) 1268 continue; 1269 if (B.size() == 0) { 1270 // A labeled empty statement, or the entry block... 1271 HasPlainEdge = true; 1272 continue; 1273 } 1274 Stmt *S = B[B.size()-1]; 1275 if (isa<ReturnStmt>(S)) { 1276 HasLiveReturn = true; 1277 continue; 1278 } 1279 if (isa<ObjCAtThrowStmt>(S)) { 1280 HasFakeEdge = true; 1281 continue; 1282 } 1283 if (isa<CXXThrowExpr>(S)) { 1284 HasFakeEdge = true; 1285 continue; 1286 } 1287 bool NoReturnEdge = false; 1288 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1289 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1290 if (CEE->getType().getNoReturnAttr()) { 1291 NoReturnEdge = true; 1292 HasFakeEdge = true; 1293 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1294 ValueDecl *VD = DRE->getDecl(); 1295 if (VD->hasAttr<NoReturnAttr>()) { 1296 NoReturnEdge = true; 1297 HasFakeEdge = true; 1298 } 1299 } 1300 } 1301 // FIXME: Add noreturn message sends. 1302 if (NoReturnEdge == false) 1303 HasPlainEdge = true; 1304 } 1305 if (!HasPlainEdge) { 1306 if (HasLiveReturn) 1307 return NeverFallThrough; 1308 return NeverFallThroughOrReturn; 1309 } 1310 if (HasFakeEdge || HasLiveReturn) 1311 return MaybeFallThrough; 1312 // This says AlwaysFallThrough for calls to functions that are not marked 1313 // noreturn, that don't return. If people would like this warning to be more 1314 // accurate, such functions should be marked as noreturn. 1315 return AlwaysFallThrough; 1316} 1317 1318/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1319/// function that should return a value. Check that we don't fall off the end 1320/// of a noreturn function. We assume that functions and blocks not marked 1321/// noreturn will return. 1322void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1323 // FIXME: Would be nice if we had a better way to control cascading errors, 1324 // but for now, avoid them. The problem is that when Parse sees: 1325 // int foo() { return a; } 1326 // The return is eaten and the Sema code sees just: 1327 // int foo() { } 1328 // which this code would then warn about. 1329 if (getDiagnostics().hasErrorOccurred()) 1330 return; 1331 1332 bool ReturnsVoid = false; 1333 bool HasNoReturn = false; 1334 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1335 // If the result type of the function is a dependent type, we don't know 1336 // whether it will be void or not, so don't 1337 if (FD->getResultType()->isDependentType()) 1338 return; 1339 if (FD->getResultType()->isVoidType()) 1340 ReturnsVoid = true; 1341 if (FD->hasAttr<NoReturnAttr>()) 1342 HasNoReturn = true; 1343 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1344 if (MD->getResultType()->isVoidType()) 1345 ReturnsVoid = true; 1346 if (MD->hasAttr<NoReturnAttr>()) 1347 HasNoReturn = true; 1348 } 1349 1350 // Short circuit for compilation speed. 1351 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1352 == Diagnostic::Ignored || ReturnsVoid) 1353 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1354 == Diagnostic::Ignored || !HasNoReturn) 1355 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1356 == Diagnostic::Ignored || !ReturnsVoid)) 1357 return; 1358 // FIXME: Function try block 1359 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1360 switch (CheckFallThrough(Body)) { 1361 case MaybeFallThrough: 1362 if (HasNoReturn) 1363 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1364 else if (!ReturnsVoid) 1365 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1366 break; 1367 case AlwaysFallThrough: 1368 if (HasNoReturn) 1369 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1370 else if (!ReturnsVoid) 1371 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1372 break; 1373 case NeverFallThroughOrReturn: 1374 if (ReturnsVoid && !HasNoReturn) 1375 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1376 break; 1377 case NeverFallThrough: 1378 break; 1379 } 1380 } 1381} 1382 1383/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1384/// that should return a value. Check that we don't fall off the end of a 1385/// noreturn block. We assume that functions and blocks not marked noreturn 1386/// will return. 1387void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1388 // FIXME: Would be nice if we had a better way to control cascading errors, 1389 // but for now, avoid them. The problem is that when Parse sees: 1390 // int foo() { return a; } 1391 // The return is eaten and the Sema code sees just: 1392 // int foo() { } 1393 // which this code would then warn about. 1394 if (getDiagnostics().hasErrorOccurred()) 1395 return; 1396 bool ReturnsVoid = false; 1397 bool HasNoReturn = false; 1398 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1399 if (FT->getResultType()->isVoidType()) 1400 ReturnsVoid = true; 1401 if (FT->getNoReturnAttr()) 1402 HasNoReturn = true; 1403 } 1404 1405 // Short circuit for compilation speed. 1406 if (ReturnsVoid 1407 && !HasNoReturn 1408 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1409 == Diagnostic::Ignored || !ReturnsVoid)) 1410 return; 1411 // FIXME: Funtion try block 1412 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1413 switch (CheckFallThrough(Body)) { 1414 case MaybeFallThrough: 1415 if (HasNoReturn) 1416 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1417 else if (!ReturnsVoid) 1418 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1419 break; 1420 case AlwaysFallThrough: 1421 if (HasNoReturn) 1422 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1423 else if (!ReturnsVoid) 1424 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1425 break; 1426 case NeverFallThroughOrReturn: 1427 if (ReturnsVoid) 1428 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1429 break; 1430 case NeverFallThrough: 1431 break; 1432 } 1433 } 1434} 1435 1436/// CheckParmsForFunctionDef - Check that the parameters of the given 1437/// function are appropriate for the definition of a function. This 1438/// takes care of any checks that cannot be performed on the 1439/// declaration itself, e.g., that the types of each of the function 1440/// parameters are complete. 1441bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1442 bool HasInvalidParm = false; 1443 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1444 ParmVarDecl *Param = FD->getParamDecl(p); 1445 1446 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1447 // function declarator that is part of a function definition of 1448 // that function shall not have incomplete type. 1449 // 1450 // This is also C++ [dcl.fct]p6. 1451 if (!Param->isInvalidDecl() && 1452 RequireCompleteType(Param->getLocation(), Param->getType(), 1453 diag::err_typecheck_decl_incomplete_type)) { 1454 Param->setInvalidDecl(); 1455 HasInvalidParm = true; 1456 } 1457 1458 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1459 // declaration of each parameter shall include an identifier. 1460 if (Param->getIdentifier() == 0 && 1461 !Param->isImplicit() && 1462 !getLangOptions().CPlusPlus) 1463 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1464 } 1465 1466 return HasInvalidParm; 1467} 1468 1469/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1470/// no declarator (e.g. "struct foo;") is parsed. 1471Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1472 // FIXME: Error on auto/register at file scope 1473 // FIXME: Error on inline/virtual/explicit 1474 // FIXME: Warn on useless __thread 1475 // FIXME: Warn on useless const/volatile 1476 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1477 // FIXME: Warn on useless attributes 1478 Decl *TagD = 0; 1479 TagDecl *Tag = 0; 1480 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1481 DS.getTypeSpecType() == DeclSpec::TST_struct || 1482 DS.getTypeSpecType() == DeclSpec::TST_union || 1483 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1484 TagD = static_cast<Decl *>(DS.getTypeRep()); 1485 1486 if (!TagD) // We probably had an error 1487 return DeclPtrTy(); 1488 1489 // Note that the above type specs guarantee that the 1490 // type rep is a Decl, whereas in many of the others 1491 // it's a Type. 1492 Tag = dyn_cast<TagDecl>(TagD); 1493 } 1494 1495 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1496 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1497 // or incomplete types shall not be restrict-qualified." 1498 if (TypeQuals & DeclSpec::TQ_restrict) 1499 Diag(DS.getRestrictSpecLoc(), 1500 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1501 << DS.getSourceRange(); 1502 } 1503 1504 if (DS.isFriendSpecified()) { 1505 // If we're dealing with a class template decl, assume that the 1506 // template routines are handling it. 1507 if (TagD && isa<ClassTemplateDecl>(TagD)) 1508 return DeclPtrTy(); 1509 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1510 } 1511 1512 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1513 // If there are attributes in the DeclSpec, apply them to the record. 1514 if (const AttributeList *AL = DS.getAttributes()) 1515 ProcessDeclAttributeList(S, Record, AL); 1516 1517 if (!Record->getDeclName() && Record->isDefinition() && 1518 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1519 if (getLangOptions().CPlusPlus || 1520 Record->getDeclContext()->isRecord()) 1521 return BuildAnonymousStructOrUnion(S, DS, Record); 1522 1523 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1524 << DS.getSourceRange(); 1525 } 1526 1527 // Microsoft allows unnamed struct/union fields. Don't complain 1528 // about them. 1529 // FIXME: Should we support Microsoft's extensions in this area? 1530 if (Record->getDeclName() && getLangOptions().Microsoft) 1531 return DeclPtrTy::make(Tag); 1532 } 1533 1534 if (!DS.isMissingDeclaratorOk() && 1535 DS.getTypeSpecType() != DeclSpec::TST_error) { 1536 // Warn about typedefs of enums without names, since this is an 1537 // extension in both Microsoft an GNU. 1538 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1539 Tag && isa<EnumDecl>(Tag)) { 1540 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1541 << DS.getSourceRange(); 1542 return DeclPtrTy::make(Tag); 1543 } 1544 1545 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1546 << DS.getSourceRange(); 1547 return DeclPtrTy(); 1548 } 1549 1550 return DeclPtrTy::make(Tag); 1551} 1552 1553/// We are trying to inject an anonymous member into the given scope; 1554/// check if there's an existing declaration that can't be overloaded. 1555/// 1556/// \return true if this is a forbidden redeclaration 1557static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1558 Scope *S, 1559 DeclarationName Name, 1560 SourceLocation NameLoc, 1561 unsigned diagnostic) { 1562 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1563 Sema::ForRedeclaration); 1564 if (!SemaRef.LookupName(R, S)) return false; 1565 1566 if (R.getAsSingle<TagDecl>()) 1567 return false; 1568 1569 // Pick a representative declaration. 1570 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1571 1572 SemaRef.Diag(NameLoc, diagnostic) << Name; 1573 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1574 1575 return true; 1576} 1577 1578/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1579/// anonymous struct or union AnonRecord into the owning context Owner 1580/// and scope S. This routine will be invoked just after we realize 1581/// that an unnamed union or struct is actually an anonymous union or 1582/// struct, e.g., 1583/// 1584/// @code 1585/// union { 1586/// int i; 1587/// float f; 1588/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1589/// // f into the surrounding scope.x 1590/// @endcode 1591/// 1592/// This routine is recursive, injecting the names of nested anonymous 1593/// structs/unions into the owning context and scope as well. 1594bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1595 RecordDecl *AnonRecord) { 1596 unsigned diagKind 1597 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1598 : diag::err_anonymous_struct_member_redecl; 1599 1600 bool Invalid = false; 1601 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1602 FEnd = AnonRecord->field_end(); 1603 F != FEnd; ++F) { 1604 if ((*F)->getDeclName()) { 1605 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1606 (*F)->getLocation(), diagKind)) { 1607 // C++ [class.union]p2: 1608 // The names of the members of an anonymous union shall be 1609 // distinct from the names of any other entity in the 1610 // scope in which the anonymous union is declared. 1611 Invalid = true; 1612 } else { 1613 // C++ [class.union]p2: 1614 // For the purpose of name lookup, after the anonymous union 1615 // definition, the members of the anonymous union are 1616 // considered to have been defined in the scope in which the 1617 // anonymous union is declared. 1618 Owner->makeDeclVisibleInContext(*F); 1619 S->AddDecl(DeclPtrTy::make(*F)); 1620 IdResolver.AddDecl(*F); 1621 } 1622 } else if (const RecordType *InnerRecordType 1623 = (*F)->getType()->getAs<RecordType>()) { 1624 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1625 if (InnerRecord->isAnonymousStructOrUnion()) 1626 Invalid = Invalid || 1627 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1628 } 1629 } 1630 1631 return Invalid; 1632} 1633 1634/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1635/// anonymous structure or union. Anonymous unions are a C++ feature 1636/// (C++ [class.union]) and a GNU C extension; anonymous structures 1637/// are a GNU C and GNU C++ extension. 1638Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1639 RecordDecl *Record) { 1640 DeclContext *Owner = Record->getDeclContext(); 1641 1642 // Diagnose whether this anonymous struct/union is an extension. 1643 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1644 Diag(Record->getLocation(), diag::ext_anonymous_union); 1645 else if (!Record->isUnion()) 1646 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1647 1648 // C and C++ require different kinds of checks for anonymous 1649 // structs/unions. 1650 bool Invalid = false; 1651 if (getLangOptions().CPlusPlus) { 1652 const char* PrevSpec = 0; 1653 unsigned DiagID; 1654 // C++ [class.union]p3: 1655 // Anonymous unions declared in a named namespace or in the 1656 // global namespace shall be declared static. 1657 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1658 (isa<TranslationUnitDecl>(Owner) || 1659 (isa<NamespaceDecl>(Owner) && 1660 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1661 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1662 Invalid = true; 1663 1664 // Recover by adding 'static'. 1665 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1666 PrevSpec, DiagID); 1667 } 1668 // C++ [class.union]p3: 1669 // A storage class is not allowed in a declaration of an 1670 // anonymous union in a class scope. 1671 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1672 isa<RecordDecl>(Owner)) { 1673 Diag(DS.getStorageClassSpecLoc(), 1674 diag::err_anonymous_union_with_storage_spec); 1675 Invalid = true; 1676 1677 // Recover by removing the storage specifier. 1678 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1679 PrevSpec, DiagID); 1680 } 1681 1682 // C++ [class.union]p2: 1683 // The member-specification of an anonymous union shall only 1684 // define non-static data members. [Note: nested types and 1685 // functions cannot be declared within an anonymous union. ] 1686 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1687 MemEnd = Record->decls_end(); 1688 Mem != MemEnd; ++Mem) { 1689 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1690 // C++ [class.union]p3: 1691 // An anonymous union shall not have private or protected 1692 // members (clause 11). 1693 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1694 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1695 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1696 Invalid = true; 1697 } 1698 } else if ((*Mem)->isImplicit()) { 1699 // Any implicit members are fine. 1700 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1701 // This is a type that showed up in an 1702 // elaborated-type-specifier inside the anonymous struct or 1703 // union, but which actually declares a type outside of the 1704 // anonymous struct or union. It's okay. 1705 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1706 if (!MemRecord->isAnonymousStructOrUnion() && 1707 MemRecord->getDeclName()) { 1708 // This is a nested type declaration. 1709 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1710 << (int)Record->isUnion(); 1711 Invalid = true; 1712 } 1713 } else { 1714 // We have something that isn't a non-static data 1715 // member. Complain about it. 1716 unsigned DK = diag::err_anonymous_record_bad_member; 1717 if (isa<TypeDecl>(*Mem)) 1718 DK = diag::err_anonymous_record_with_type; 1719 else if (isa<FunctionDecl>(*Mem)) 1720 DK = diag::err_anonymous_record_with_function; 1721 else if (isa<VarDecl>(*Mem)) 1722 DK = diag::err_anonymous_record_with_static; 1723 Diag((*Mem)->getLocation(), DK) 1724 << (int)Record->isUnion(); 1725 Invalid = true; 1726 } 1727 } 1728 } 1729 1730 if (!Record->isUnion() && !Owner->isRecord()) { 1731 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1732 << (int)getLangOptions().CPlusPlus; 1733 Invalid = true; 1734 } 1735 1736 // Mock up a declarator. 1737 Declarator Dc(DS, Declarator::TypeNameContext); 1738 TypeSourceInfo *TInfo = 0; 1739 GetTypeForDeclarator(Dc, S, &TInfo); 1740 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1741 1742 // Create a declaration for this anonymous struct/union. 1743 NamedDecl *Anon = 0; 1744 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1745 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1746 /*IdentifierInfo=*/0, 1747 Context.getTypeDeclType(Record), 1748 TInfo, 1749 /*BitWidth=*/0, /*Mutable=*/false); 1750 Anon->setAccess(AS_public); 1751 if (getLangOptions().CPlusPlus) 1752 FieldCollector->Add(cast<FieldDecl>(Anon)); 1753 } else { 1754 VarDecl::StorageClass SC; 1755 switch (DS.getStorageClassSpec()) { 1756 default: assert(0 && "Unknown storage class!"); 1757 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1758 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1759 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1760 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1761 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1762 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1763 case DeclSpec::SCS_mutable: 1764 // mutable can only appear on non-static class members, so it's always 1765 // an error here 1766 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1767 Invalid = true; 1768 SC = VarDecl::None; 1769 break; 1770 } 1771 1772 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1773 /*IdentifierInfo=*/0, 1774 Context.getTypeDeclType(Record), 1775 TInfo, 1776 SC); 1777 } 1778 Anon->setImplicit(); 1779 1780 // Add the anonymous struct/union object to the current 1781 // context. We'll be referencing this object when we refer to one of 1782 // its members. 1783 Owner->addDecl(Anon); 1784 1785 // Inject the members of the anonymous struct/union into the owning 1786 // context and into the identifier resolver chain for name lookup 1787 // purposes. 1788 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1789 Invalid = true; 1790 1791 // Mark this as an anonymous struct/union type. Note that we do not 1792 // do this until after we have already checked and injected the 1793 // members of this anonymous struct/union type, because otherwise 1794 // the members could be injected twice: once by DeclContext when it 1795 // builds its lookup table, and once by 1796 // InjectAnonymousStructOrUnionMembers. 1797 Record->setAnonymousStructOrUnion(true); 1798 1799 if (Invalid) 1800 Anon->setInvalidDecl(); 1801 1802 return DeclPtrTy::make(Anon); 1803} 1804 1805 1806/// GetNameForDeclarator - Determine the full declaration name for the 1807/// given Declarator. 1808DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1809 return GetNameFromUnqualifiedId(D.getName()); 1810} 1811 1812/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1813DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1814 switch (Name.getKind()) { 1815 case UnqualifiedId::IK_Identifier: 1816 return DeclarationName(Name.Identifier); 1817 1818 case UnqualifiedId::IK_OperatorFunctionId: 1819 return Context.DeclarationNames.getCXXOperatorName( 1820 Name.OperatorFunctionId.Operator); 1821 1822 case UnqualifiedId::IK_LiteralOperatorId: 1823 return Context.DeclarationNames.getCXXLiteralOperatorName( 1824 Name.Identifier); 1825 1826 case UnqualifiedId::IK_ConversionFunctionId: { 1827 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1828 if (Ty.isNull()) 1829 return DeclarationName(); 1830 1831 return Context.DeclarationNames.getCXXConversionFunctionName( 1832 Context.getCanonicalType(Ty)); 1833 } 1834 1835 case UnqualifiedId::IK_ConstructorName: { 1836 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1837 if (Ty.isNull()) 1838 return DeclarationName(); 1839 1840 return Context.DeclarationNames.getCXXConstructorName( 1841 Context.getCanonicalType(Ty)); 1842 } 1843 1844 case UnqualifiedId::IK_DestructorName: { 1845 QualType Ty = GetTypeFromParser(Name.DestructorName); 1846 if (Ty.isNull()) 1847 return DeclarationName(); 1848 1849 return Context.DeclarationNames.getCXXDestructorName( 1850 Context.getCanonicalType(Ty)); 1851 } 1852 1853 case UnqualifiedId::IK_TemplateId: { 1854 TemplateName TName 1855 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1856 return Context.getNameForTemplate(TName); 1857 } 1858 } 1859 1860 assert(false && "Unknown name kind"); 1861 return DeclarationName(); 1862} 1863 1864/// isNearlyMatchingFunction - Determine whether the C++ functions 1865/// Declaration and Definition are "nearly" matching. This heuristic 1866/// is used to improve diagnostics in the case where an out-of-line 1867/// function definition doesn't match any declaration within 1868/// the class or namespace. 1869static bool isNearlyMatchingFunction(ASTContext &Context, 1870 FunctionDecl *Declaration, 1871 FunctionDecl *Definition) { 1872 if (Declaration->param_size() != Definition->param_size()) 1873 return false; 1874 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1875 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1876 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1877 1878 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1879 DefParamTy.getNonReferenceType())) 1880 return false; 1881 } 1882 1883 return true; 1884} 1885 1886Sema::DeclPtrTy 1887Sema::HandleDeclarator(Scope *S, Declarator &D, 1888 MultiTemplateParamsArg TemplateParamLists, 1889 bool IsFunctionDefinition) { 1890 DeclarationName Name = GetNameForDeclarator(D); 1891 1892 // All of these full declarators require an identifier. If it doesn't have 1893 // one, the ParsedFreeStandingDeclSpec action should be used. 1894 if (!Name) { 1895 if (!D.isInvalidType()) // Reject this if we think it is valid. 1896 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1897 diag::err_declarator_need_ident) 1898 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1899 return DeclPtrTy(); 1900 } 1901 1902 // The scope passed in may not be a decl scope. Zip up the scope tree until 1903 // we find one that is. 1904 while ((S->getFlags() & Scope::DeclScope) == 0 || 1905 (S->getFlags() & Scope::TemplateParamScope) != 0) 1906 S = S->getParent(); 1907 1908 // If this is an out-of-line definition of a member of a class template 1909 // or class template partial specialization, we may need to rebuild the 1910 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1911 // for more information. 1912 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1913 // handle expressions properly. 1914 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1915 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1916 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1917 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1918 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1919 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1920 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1921 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1922 // FIXME: Preserve type source info. 1923 QualType T = GetTypeFromParser(DS.getTypeRep()); 1924 1925 DeclContext *SavedContext = CurContext; 1926 CurContext = DC; 1927 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1928 CurContext = SavedContext; 1929 1930 if (T.isNull()) 1931 return DeclPtrTy(); 1932 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1933 } 1934 } 1935 1936 DeclContext *DC; 1937 NamedDecl *New; 1938 1939 TypeSourceInfo *TInfo = 0; 1940 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1941 1942 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1943 ForRedeclaration); 1944 1945 // See if this is a redefinition of a variable in the same scope. 1946 if (D.getCXXScopeSpec().isInvalid()) { 1947 DC = CurContext; 1948 D.setInvalidType(); 1949 } else if (!D.getCXXScopeSpec().isSet()) { 1950 bool IsLinkageLookup = false; 1951 1952 // If the declaration we're planning to build will be a function 1953 // or object with linkage, then look for another declaration with 1954 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1955 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1956 /* Do nothing*/; 1957 else if (R->isFunctionType()) { 1958 if (CurContext->isFunctionOrMethod() || 1959 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1960 IsLinkageLookup = true; 1961 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1962 IsLinkageLookup = true; 1963 else if (CurContext->getLookupContext()->isTranslationUnit() && 1964 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1965 IsLinkageLookup = true; 1966 1967 if (IsLinkageLookup) 1968 Previous.clear(LookupRedeclarationWithLinkage); 1969 1970 DC = CurContext; 1971 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1972 } else { // Something like "int foo::x;" 1973 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1974 1975 if (!DC) { 1976 // If we could not compute the declaration context, it's because the 1977 // declaration context is dependent but does not refer to a class, 1978 // class template, or class template partial specialization. Complain 1979 // and return early, to avoid the coming semantic disaster. 1980 Diag(D.getIdentifierLoc(), 1981 diag::err_template_qualified_declarator_no_match) 1982 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1983 << D.getCXXScopeSpec().getRange(); 1984 return DeclPtrTy(); 1985 } 1986 1987 if (!DC->isDependentContext() && 1988 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1989 return DeclPtrTy(); 1990 1991 LookupQualifiedName(Previous, DC); 1992 1993 // Don't consider using declarations as previous declarations for 1994 // out-of-line members. 1995 RemoveUsingDecls(Previous); 1996 1997 // C++ 7.3.1.2p2: 1998 // Members (including explicit specializations of templates) of a named 1999 // namespace can also be defined outside that namespace by explicit 2000 // qualification of the name being defined, provided that the entity being 2001 // defined was already declared in the namespace and the definition appears 2002 // after the point of declaration in a namespace that encloses the 2003 // declarations namespace. 2004 // 2005 // Note that we only check the context at this point. We don't yet 2006 // have enough information to make sure that PrevDecl is actually 2007 // the declaration we want to match. For example, given: 2008 // 2009 // class X { 2010 // void f(); 2011 // void f(float); 2012 // }; 2013 // 2014 // void X::f(int) { } // ill-formed 2015 // 2016 // In this case, PrevDecl will point to the overload set 2017 // containing the two f's declared in X, but neither of them 2018 // matches. 2019 2020 // First check whether we named the global scope. 2021 if (isa<TranslationUnitDecl>(DC)) { 2022 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2023 << Name << D.getCXXScopeSpec().getRange(); 2024 } else { 2025 DeclContext *Cur = CurContext; 2026 while (isa<LinkageSpecDecl>(Cur)) 2027 Cur = Cur->getParent(); 2028 if (!Cur->Encloses(DC)) { 2029 // The qualifying scope doesn't enclose the original declaration. 2030 // Emit diagnostic based on current scope. 2031 SourceLocation L = D.getIdentifierLoc(); 2032 SourceRange R = D.getCXXScopeSpec().getRange(); 2033 if (isa<FunctionDecl>(Cur)) 2034 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2035 else 2036 Diag(L, diag::err_invalid_declarator_scope) 2037 << Name << cast<NamedDecl>(DC) << R; 2038 D.setInvalidType(); 2039 } 2040 } 2041 } 2042 2043 if (Previous.isSingleResult() && 2044 Previous.getFoundDecl()->isTemplateParameter()) { 2045 // Maybe we will complain about the shadowed template parameter. 2046 if (!D.isInvalidType()) 2047 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2048 Previous.getFoundDecl())) 2049 D.setInvalidType(); 2050 2051 // Just pretend that we didn't see the previous declaration. 2052 Previous.clear(); 2053 } 2054 2055 // In C++, the previous declaration we find might be a tag type 2056 // (class or enum). In this case, the new declaration will hide the 2057 // tag type. Note that this does does not apply if we're declaring a 2058 // typedef (C++ [dcl.typedef]p4). 2059 if (Previous.isSingleTagDecl() && 2060 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2061 Previous.clear(); 2062 2063 bool Redeclaration = false; 2064 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2065 if (TemplateParamLists.size()) { 2066 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2067 return DeclPtrTy(); 2068 } 2069 2070 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2071 } else if (R->isFunctionType()) { 2072 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2073 move(TemplateParamLists), 2074 IsFunctionDefinition, Redeclaration); 2075 } else { 2076 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2077 move(TemplateParamLists), 2078 Redeclaration); 2079 } 2080 2081 if (New == 0) 2082 return DeclPtrTy(); 2083 2084 // If this has an identifier and is not an invalid redeclaration or 2085 // function template specialization, add it to the scope stack. 2086 if (Name && !(Redeclaration && New->isInvalidDecl())) 2087 PushOnScopeChains(New, S); 2088 2089 return DeclPtrTy::make(New); 2090} 2091 2092/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2093/// types into constant array types in certain situations which would otherwise 2094/// be errors (for GCC compatibility). 2095static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2096 ASTContext &Context, 2097 bool &SizeIsNegative) { 2098 // This method tries to turn a variable array into a constant 2099 // array even when the size isn't an ICE. This is necessary 2100 // for compatibility with code that depends on gcc's buggy 2101 // constant expression folding, like struct {char x[(int)(char*)2];} 2102 SizeIsNegative = false; 2103 2104 QualifierCollector Qs; 2105 const Type *Ty = Qs.strip(T); 2106 2107 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2108 QualType Pointee = PTy->getPointeeType(); 2109 QualType FixedType = 2110 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2111 if (FixedType.isNull()) return FixedType; 2112 FixedType = Context.getPointerType(FixedType); 2113 return Qs.apply(FixedType); 2114 } 2115 2116 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2117 if (!VLATy) 2118 return QualType(); 2119 // FIXME: We should probably handle this case 2120 if (VLATy->getElementType()->isVariablyModifiedType()) 2121 return QualType(); 2122 2123 Expr::EvalResult EvalResult; 2124 if (!VLATy->getSizeExpr() || 2125 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2126 !EvalResult.Val.isInt()) 2127 return QualType(); 2128 2129 llvm::APSInt &Res = EvalResult.Val.getInt(); 2130 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2131 // TODO: preserve the size expression in declarator info 2132 return Context.getConstantArrayType(VLATy->getElementType(), 2133 Res, ArrayType::Normal, 0); 2134 } 2135 2136 SizeIsNegative = true; 2137 return QualType(); 2138} 2139 2140/// \brief Register the given locally-scoped external C declaration so 2141/// that it can be found later for redeclarations 2142void 2143Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2144 const LookupResult &Previous, 2145 Scope *S) { 2146 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2147 "Decl is not a locally-scoped decl!"); 2148 // Note that we have a locally-scoped external with this name. 2149 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2150 2151 if (!Previous.isSingleResult()) 2152 return; 2153 2154 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2155 2156 // If there was a previous declaration of this variable, it may be 2157 // in our identifier chain. Update the identifier chain with the new 2158 // declaration. 2159 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2160 // The previous declaration was found on the identifer resolver 2161 // chain, so remove it from its scope. 2162 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2163 S = S->getParent(); 2164 2165 if (S) 2166 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2167 } 2168} 2169 2170/// \brief Diagnose function specifiers on a declaration of an identifier that 2171/// does not identify a function. 2172void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2173 // FIXME: We should probably indicate the identifier in question to avoid 2174 // confusion for constructs like "inline int a(), b;" 2175 if (D.getDeclSpec().isInlineSpecified()) 2176 Diag(D.getDeclSpec().getInlineSpecLoc(), 2177 diag::err_inline_non_function); 2178 2179 if (D.getDeclSpec().isVirtualSpecified()) 2180 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2181 diag::err_virtual_non_function); 2182 2183 if (D.getDeclSpec().isExplicitSpecified()) 2184 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2185 diag::err_explicit_non_function); 2186} 2187 2188NamedDecl* 2189Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2190 QualType R, TypeSourceInfo *TInfo, 2191 LookupResult &Previous, bool &Redeclaration) { 2192 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2193 if (D.getCXXScopeSpec().isSet()) { 2194 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2195 << D.getCXXScopeSpec().getRange(); 2196 D.setInvalidType(); 2197 // Pretend we didn't see the scope specifier. 2198 DC = 0; 2199 } 2200 2201 if (getLangOptions().CPlusPlus) { 2202 // Check that there are no default arguments (C++ only). 2203 CheckExtraCXXDefaultArguments(D); 2204 } 2205 2206 DiagnoseFunctionSpecifiers(D); 2207 2208 if (D.getDeclSpec().isThreadSpecified()) 2209 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2210 2211 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2212 if (!NewTD) return 0; 2213 2214 // Handle attributes prior to checking for duplicates in MergeVarDecl 2215 ProcessDeclAttributes(S, NewTD, D); 2216 2217 // Merge the decl with the existing one if appropriate. If the decl is 2218 // in an outer scope, it isn't the same thing. 2219 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2220 if (!Previous.empty()) { 2221 Redeclaration = true; 2222 MergeTypeDefDecl(NewTD, Previous); 2223 } 2224 2225 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2226 // then it shall have block scope. 2227 QualType T = NewTD->getUnderlyingType(); 2228 if (T->isVariablyModifiedType()) { 2229 CurFunctionNeedsScopeChecking = true; 2230 2231 if (S->getFnParent() == 0) { 2232 bool SizeIsNegative; 2233 QualType FixedTy = 2234 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2235 if (!FixedTy.isNull()) { 2236 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2237 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2238 } else { 2239 if (SizeIsNegative) 2240 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2241 else if (T->isVariableArrayType()) 2242 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2243 else 2244 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2245 NewTD->setInvalidDecl(); 2246 } 2247 } 2248 } 2249 2250 // If this is the C FILE type, notify the AST context. 2251 if (IdentifierInfo *II = NewTD->getIdentifier()) 2252 if (!NewTD->isInvalidDecl() && 2253 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2254 if (II->isStr("FILE")) 2255 Context.setFILEDecl(NewTD); 2256 else if (II->isStr("jmp_buf")) 2257 Context.setjmp_bufDecl(NewTD); 2258 else if (II->isStr("sigjmp_buf")) 2259 Context.setsigjmp_bufDecl(NewTD); 2260 } 2261 2262 return NewTD; 2263} 2264 2265/// \brief Determines whether the given declaration is an out-of-scope 2266/// previous declaration. 2267/// 2268/// This routine should be invoked when name lookup has found a 2269/// previous declaration (PrevDecl) that is not in the scope where a 2270/// new declaration by the same name is being introduced. If the new 2271/// declaration occurs in a local scope, previous declarations with 2272/// linkage may still be considered previous declarations (C99 2273/// 6.2.2p4-5, C++ [basic.link]p6). 2274/// 2275/// \param PrevDecl the previous declaration found by name 2276/// lookup 2277/// 2278/// \param DC the context in which the new declaration is being 2279/// declared. 2280/// 2281/// \returns true if PrevDecl is an out-of-scope previous declaration 2282/// for a new delcaration with the same name. 2283static bool 2284isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2285 ASTContext &Context) { 2286 if (!PrevDecl) 2287 return 0; 2288 2289 if (!PrevDecl->hasLinkage()) 2290 return false; 2291 2292 if (Context.getLangOptions().CPlusPlus) { 2293 // C++ [basic.link]p6: 2294 // If there is a visible declaration of an entity with linkage 2295 // having the same name and type, ignoring entities declared 2296 // outside the innermost enclosing namespace scope, the block 2297 // scope declaration declares that same entity and receives the 2298 // linkage of the previous declaration. 2299 DeclContext *OuterContext = DC->getLookupContext(); 2300 if (!OuterContext->isFunctionOrMethod()) 2301 // This rule only applies to block-scope declarations. 2302 return false; 2303 else { 2304 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2305 if (PrevOuterContext->isRecord()) 2306 // We found a member function: ignore it. 2307 return false; 2308 else { 2309 // Find the innermost enclosing namespace for the new and 2310 // previous declarations. 2311 while (!OuterContext->isFileContext()) 2312 OuterContext = OuterContext->getParent(); 2313 while (!PrevOuterContext->isFileContext()) 2314 PrevOuterContext = PrevOuterContext->getParent(); 2315 2316 // The previous declaration is in a different namespace, so it 2317 // isn't the same function. 2318 if (OuterContext->getPrimaryContext() != 2319 PrevOuterContext->getPrimaryContext()) 2320 return false; 2321 } 2322 } 2323 } 2324 2325 return true; 2326} 2327 2328NamedDecl* 2329Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2330 QualType R, TypeSourceInfo *TInfo, 2331 LookupResult &Previous, 2332 MultiTemplateParamsArg TemplateParamLists, 2333 bool &Redeclaration) { 2334 DeclarationName Name = GetNameForDeclarator(D); 2335 2336 // Check that there are no default arguments (C++ only). 2337 if (getLangOptions().CPlusPlus) 2338 CheckExtraCXXDefaultArguments(D); 2339 2340 VarDecl *NewVD; 2341 VarDecl::StorageClass SC; 2342 switch (D.getDeclSpec().getStorageClassSpec()) { 2343 default: assert(0 && "Unknown storage class!"); 2344 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2345 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2346 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2347 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2348 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2349 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2350 case DeclSpec::SCS_mutable: 2351 // mutable can only appear on non-static class members, so it's always 2352 // an error here 2353 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2354 D.setInvalidType(); 2355 SC = VarDecl::None; 2356 break; 2357 } 2358 2359 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2360 if (!II) { 2361 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2362 << Name.getAsString(); 2363 return 0; 2364 } 2365 2366 DiagnoseFunctionSpecifiers(D); 2367 2368 if (!DC->isRecord() && S->getFnParent() == 0) { 2369 // C99 6.9p2: The storage-class specifiers auto and register shall not 2370 // appear in the declaration specifiers in an external declaration. 2371 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2372 2373 // If this is a register variable with an asm label specified, then this 2374 // is a GNU extension. 2375 if (SC == VarDecl::Register && D.getAsmLabel()) 2376 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2377 else 2378 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2379 D.setInvalidType(); 2380 } 2381 } 2382 if (DC->isRecord() && !CurContext->isRecord()) { 2383 // This is an out-of-line definition of a static data member. 2384 if (SC == VarDecl::Static) { 2385 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2386 diag::err_static_out_of_line) 2387 << CodeModificationHint::CreateRemoval( 2388 D.getDeclSpec().getStorageClassSpecLoc()); 2389 } else if (SC == VarDecl::None) 2390 SC = VarDecl::Static; 2391 } 2392 if (SC == VarDecl::Static) { 2393 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2394 if (RD->isLocalClass()) 2395 Diag(D.getIdentifierLoc(), 2396 diag::err_static_data_member_not_allowed_in_local_class) 2397 << Name << RD->getDeclName(); 2398 } 2399 } 2400 2401 // Match up the template parameter lists with the scope specifier, then 2402 // determine whether we have a template or a template specialization. 2403 bool isExplicitSpecialization = false; 2404 if (TemplateParameterList *TemplateParams 2405 = MatchTemplateParametersToScopeSpecifier( 2406 D.getDeclSpec().getSourceRange().getBegin(), 2407 D.getCXXScopeSpec(), 2408 (TemplateParameterList**)TemplateParamLists.get(), 2409 TemplateParamLists.size(), 2410 isExplicitSpecialization)) { 2411 if (TemplateParams->size() > 0) { 2412 // There is no such thing as a variable template. 2413 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2414 << II 2415 << SourceRange(TemplateParams->getTemplateLoc(), 2416 TemplateParams->getRAngleLoc()); 2417 return 0; 2418 } else { 2419 // There is an extraneous 'template<>' for this variable. Complain 2420 // about it, but allow the declaration of the variable. 2421 Diag(TemplateParams->getTemplateLoc(), 2422 diag::err_template_variable_noparams) 2423 << II 2424 << SourceRange(TemplateParams->getTemplateLoc(), 2425 TemplateParams->getRAngleLoc()); 2426 2427 isExplicitSpecialization = true; 2428 } 2429 } 2430 2431 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2432 II, R, TInfo, SC); 2433 2434 if (D.isInvalidType()) 2435 NewVD->setInvalidDecl(); 2436 2437 if (D.getDeclSpec().isThreadSpecified()) { 2438 if (NewVD->hasLocalStorage()) 2439 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2440 else if (!Context.Target.isTLSSupported()) 2441 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2442 else 2443 NewVD->setThreadSpecified(true); 2444 } 2445 2446 // Set the lexical context. If the declarator has a C++ scope specifier, the 2447 // lexical context will be different from the semantic context. 2448 NewVD->setLexicalDeclContext(CurContext); 2449 2450 // Handle attributes prior to checking for duplicates in MergeVarDecl 2451 ProcessDeclAttributes(S, NewVD, D); 2452 2453 // Handle GNU asm-label extension (encoded as an attribute). 2454 if (Expr *E = (Expr*) D.getAsmLabel()) { 2455 // The parser guarantees this is a string. 2456 StringLiteral *SE = cast<StringLiteral>(E); 2457 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2458 } 2459 2460 // Don't consider existing declarations that are in a different 2461 // scope and are out-of-semantic-context declarations (if the new 2462 // declaration has linkage). 2463 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2464 2465 // Merge the decl with the existing one if appropriate. 2466 if (!Previous.empty()) { 2467 if (Previous.isSingleResult() && 2468 isa<FieldDecl>(Previous.getFoundDecl()) && 2469 D.getCXXScopeSpec().isSet()) { 2470 // The user tried to define a non-static data member 2471 // out-of-line (C++ [dcl.meaning]p1). 2472 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2473 << D.getCXXScopeSpec().getRange(); 2474 Previous.clear(); 2475 NewVD->setInvalidDecl(); 2476 } 2477 } else if (D.getCXXScopeSpec().isSet()) { 2478 // No previous declaration in the qualifying scope. 2479 Diag(D.getIdentifierLoc(), diag::err_no_member) 2480 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2481 << D.getCXXScopeSpec().getRange(); 2482 NewVD->setInvalidDecl(); 2483 } 2484 2485 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2486 2487 // This is an explicit specialization of a static data member. Check it. 2488 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2489 CheckMemberSpecialization(NewVD, Previous)) 2490 NewVD->setInvalidDecl(); 2491 2492 // attributes declared post-definition are currently ignored 2493 if (Previous.isSingleResult()) { 2494 const VarDecl *Def = 0; 2495 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2496 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2497 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2498 Diag(Def->getLocation(), diag::note_previous_definition); 2499 } 2500 } 2501 2502 // If this is a locally-scoped extern C variable, update the map of 2503 // such variables. 2504 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2505 !NewVD->isInvalidDecl()) 2506 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2507 2508 return NewVD; 2509} 2510 2511/// \brief Perform semantic checking on a newly-created variable 2512/// declaration. 2513/// 2514/// This routine performs all of the type-checking required for a 2515/// variable declaration once it has been built. It is used both to 2516/// check variables after they have been parsed and their declarators 2517/// have been translated into a declaration, and to check variables 2518/// that have been instantiated from a template. 2519/// 2520/// Sets NewVD->isInvalidDecl() if an error was encountered. 2521void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2522 LookupResult &Previous, 2523 bool &Redeclaration) { 2524 // If the decl is already known invalid, don't check it. 2525 if (NewVD->isInvalidDecl()) 2526 return; 2527 2528 QualType T = NewVD->getType(); 2529 2530 if (T->isObjCInterfaceType()) { 2531 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2532 return NewVD->setInvalidDecl(); 2533 } 2534 2535 // Emit an error if an address space was applied to decl with local storage. 2536 // This includes arrays of objects with address space qualifiers, but not 2537 // automatic variables that point to other address spaces. 2538 // ISO/IEC TR 18037 S5.1.2 2539 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2540 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2541 return NewVD->setInvalidDecl(); 2542 } 2543 2544 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2545 && !NewVD->hasAttr<BlocksAttr>()) 2546 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2547 2548 bool isVM = T->isVariablyModifiedType(); 2549 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2550 NewVD->hasAttr<BlocksAttr>()) 2551 CurFunctionNeedsScopeChecking = true; 2552 2553 if ((isVM && NewVD->hasLinkage()) || 2554 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2555 bool SizeIsNegative; 2556 QualType FixedTy = 2557 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2558 2559 if (FixedTy.isNull() && T->isVariableArrayType()) { 2560 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2561 // FIXME: This won't give the correct result for 2562 // int a[10][n]; 2563 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2564 2565 if (NewVD->isFileVarDecl()) 2566 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2567 << SizeRange; 2568 else if (NewVD->getStorageClass() == VarDecl::Static) 2569 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2570 << SizeRange; 2571 else 2572 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2573 << SizeRange; 2574 return NewVD->setInvalidDecl(); 2575 } 2576 2577 if (FixedTy.isNull()) { 2578 if (NewVD->isFileVarDecl()) 2579 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2580 else 2581 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2582 return NewVD->setInvalidDecl(); 2583 } 2584 2585 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2586 NewVD->setType(FixedTy); 2587 } 2588 2589 if (Previous.empty() && NewVD->isExternC()) { 2590 // Since we did not find anything by this name and we're declaring 2591 // an extern "C" variable, look for a non-visible extern "C" 2592 // declaration with the same name. 2593 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2594 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2595 if (Pos != LocallyScopedExternalDecls.end()) 2596 Previous.addDecl(Pos->second); 2597 } 2598 2599 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2600 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2601 << T; 2602 return NewVD->setInvalidDecl(); 2603 } 2604 2605 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2606 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2607 return NewVD->setInvalidDecl(); 2608 } 2609 2610 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2611 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2612 return NewVD->setInvalidDecl(); 2613 } 2614 2615 if (!Previous.empty()) { 2616 Redeclaration = true; 2617 MergeVarDecl(NewVD, Previous); 2618 } 2619} 2620 2621/// \brief Data used with FindOverriddenMethod 2622struct FindOverriddenMethodData { 2623 Sema *S; 2624 CXXMethodDecl *Method; 2625}; 2626 2627/// \brief Member lookup function that determines whether a given C++ 2628/// method overrides a method in a base class, to be used with 2629/// CXXRecordDecl::lookupInBases(). 2630static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2631 CXXBasePath &Path, 2632 void *UserData) { 2633 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2634 2635 FindOverriddenMethodData *Data 2636 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2637 2638 DeclarationName Name = Data->Method->getDeclName(); 2639 2640 // FIXME: Do we care about other names here too? 2641 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2642 // We really want to find the base class constructor here. 2643 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2644 CanQualType CT = Data->S->Context.getCanonicalType(T); 2645 2646 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2647 } 2648 2649 for (Path.Decls = BaseRecord->lookup(Name); 2650 Path.Decls.first != Path.Decls.second; 2651 ++Path.Decls.first) { 2652 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2653 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2654 return true; 2655 } 2656 } 2657 2658 return false; 2659} 2660 2661/// AddOverriddenMethods - See if a method overrides any in the base classes, 2662/// and if so, check that it's a valid override and remember it. 2663void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2664 // Look for virtual methods in base classes that this method might override. 2665 CXXBasePaths Paths; 2666 FindOverriddenMethodData Data; 2667 Data.Method = MD; 2668 Data.S = this; 2669 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2670 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2671 E = Paths.found_decls_end(); I != E; ++I) { 2672 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2673 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2674 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2675 !CheckOverridingFunctionAttributes(MD, OldMD)) 2676 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2677 } 2678 } 2679 } 2680} 2681 2682NamedDecl* 2683Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2684 QualType R, TypeSourceInfo *TInfo, 2685 LookupResult &Previous, 2686 MultiTemplateParamsArg TemplateParamLists, 2687 bool IsFunctionDefinition, bool &Redeclaration) { 2688 assert(R.getTypePtr()->isFunctionType()); 2689 2690 DeclarationName Name = GetNameForDeclarator(D); 2691 FunctionDecl::StorageClass SC = FunctionDecl::None; 2692 switch (D.getDeclSpec().getStorageClassSpec()) { 2693 default: assert(0 && "Unknown storage class!"); 2694 case DeclSpec::SCS_auto: 2695 case DeclSpec::SCS_register: 2696 case DeclSpec::SCS_mutable: 2697 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2698 diag::err_typecheck_sclass_func); 2699 D.setInvalidType(); 2700 break; 2701 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2702 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2703 case DeclSpec::SCS_static: { 2704 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2705 // C99 6.7.1p5: 2706 // The declaration of an identifier for a function that has 2707 // block scope shall have no explicit storage-class specifier 2708 // other than extern 2709 // See also (C++ [dcl.stc]p4). 2710 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2711 diag::err_static_block_func); 2712 SC = FunctionDecl::None; 2713 } else 2714 SC = FunctionDecl::Static; 2715 break; 2716 } 2717 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2718 } 2719 2720 if (D.getDeclSpec().isThreadSpecified()) 2721 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2722 2723 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2724 bool isInline = D.getDeclSpec().isInlineSpecified(); 2725 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2726 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2727 2728 // Check that the return type is not an abstract class type. 2729 // For record types, this is done by the AbstractClassUsageDiagnoser once 2730 // the class has been completely parsed. 2731 if (!DC->isRecord() && 2732 RequireNonAbstractType(D.getIdentifierLoc(), 2733 R->getAs<FunctionType>()->getResultType(), 2734 diag::err_abstract_type_in_decl, 2735 AbstractReturnType)) 2736 D.setInvalidType(); 2737 2738 // Do not allow returning a objc interface by-value. 2739 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2740 Diag(D.getIdentifierLoc(), 2741 diag::err_object_cannot_be_passed_returned_by_value) << 0 2742 << R->getAs<FunctionType>()->getResultType(); 2743 D.setInvalidType(); 2744 } 2745 2746 bool isVirtualOkay = false; 2747 FunctionDecl *NewFD; 2748 2749 if (isFriend) { 2750 // C++ [class.friend]p5 2751 // A function can be defined in a friend declaration of a 2752 // class . . . . Such a function is implicitly inline. 2753 isInline |= IsFunctionDefinition; 2754 } 2755 2756 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2757 // This is a C++ constructor declaration. 2758 assert(DC->isRecord() && 2759 "Constructors can only be declared in a member context"); 2760 2761 R = CheckConstructorDeclarator(D, R, SC); 2762 2763 // Create the new declaration 2764 NewFD = CXXConstructorDecl::Create(Context, 2765 cast<CXXRecordDecl>(DC), 2766 D.getIdentifierLoc(), Name, R, TInfo, 2767 isExplicit, isInline, 2768 /*isImplicitlyDeclared=*/false); 2769 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2770 // This is a C++ destructor declaration. 2771 if (DC->isRecord()) { 2772 R = CheckDestructorDeclarator(D, SC); 2773 2774 NewFD = CXXDestructorDecl::Create(Context, 2775 cast<CXXRecordDecl>(DC), 2776 D.getIdentifierLoc(), Name, R, 2777 isInline, 2778 /*isImplicitlyDeclared=*/false); 2779 2780 isVirtualOkay = true; 2781 } else { 2782 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2783 2784 // Create a FunctionDecl to satisfy the function definition parsing 2785 // code path. 2786 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2787 Name, R, TInfo, SC, isInline, 2788 /*hasPrototype=*/true); 2789 D.setInvalidType(); 2790 } 2791 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2792 if (!DC->isRecord()) { 2793 Diag(D.getIdentifierLoc(), 2794 diag::err_conv_function_not_member); 2795 return 0; 2796 } 2797 2798 CheckConversionDeclarator(D, R, SC); 2799 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2800 D.getIdentifierLoc(), Name, R, TInfo, 2801 isInline, isExplicit); 2802 2803 isVirtualOkay = true; 2804 } else if (DC->isRecord()) { 2805 // If the of the function is the same as the name of the record, then this 2806 // must be an invalid constructor that has a return type. 2807 // (The parser checks for a return type and makes the declarator a 2808 // constructor if it has no return type). 2809 // must have an invalid constructor that has a return type 2810 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2811 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2812 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2813 << SourceRange(D.getIdentifierLoc()); 2814 return 0; 2815 } 2816 2817 bool isStatic = SC == FunctionDecl::Static; 2818 2819 // [class.free]p1: 2820 // Any allocation function for a class T is a static member 2821 // (even if not explicitly declared static). 2822 if (Name.getCXXOverloadedOperator() == OO_New || 2823 Name.getCXXOverloadedOperator() == OO_Array_New) 2824 isStatic = true; 2825 2826 // [class.free]p6 Any deallocation function for a class X is a static member 2827 // (even if not explicitly declared static). 2828 if (Name.getCXXOverloadedOperator() == OO_Delete || 2829 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2830 isStatic = true; 2831 2832 // This is a C++ method declaration. 2833 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2834 D.getIdentifierLoc(), Name, R, TInfo, 2835 isStatic, isInline); 2836 2837 isVirtualOkay = !isStatic; 2838 } else { 2839 // Determine whether the function was written with a 2840 // prototype. This true when: 2841 // - we're in C++ (where every function has a prototype), 2842 // - there is a prototype in the declarator, or 2843 // - the type R of the function is some kind of typedef or other reference 2844 // to a type name (which eventually refers to a function type). 2845 bool HasPrototype = 2846 getLangOptions().CPlusPlus || 2847 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2848 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2849 2850 NewFD = FunctionDecl::Create(Context, DC, 2851 D.getIdentifierLoc(), 2852 Name, R, TInfo, SC, isInline, HasPrototype); 2853 } 2854 2855 if (D.isInvalidType()) 2856 NewFD->setInvalidDecl(); 2857 2858 // Set the lexical context. If the declarator has a C++ 2859 // scope specifier, or is the object of a friend declaration, the 2860 // lexical context will be different from the semantic context. 2861 NewFD->setLexicalDeclContext(CurContext); 2862 2863 // Match up the template parameter lists with the scope specifier, then 2864 // determine whether we have a template or a template specialization. 2865 FunctionTemplateDecl *FunctionTemplate = 0; 2866 bool isExplicitSpecialization = false; 2867 bool isFunctionTemplateSpecialization = false; 2868 if (TemplateParameterList *TemplateParams 2869 = MatchTemplateParametersToScopeSpecifier( 2870 D.getDeclSpec().getSourceRange().getBegin(), 2871 D.getCXXScopeSpec(), 2872 (TemplateParameterList**)TemplateParamLists.get(), 2873 TemplateParamLists.size(), 2874 isExplicitSpecialization)) { 2875 if (TemplateParams->size() > 0) { 2876 // This is a function template 2877 2878 // Check that we can declare a template here. 2879 if (CheckTemplateDeclScope(S, TemplateParams)) 2880 return 0; 2881 2882 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2883 NewFD->getLocation(), 2884 Name, TemplateParams, 2885 NewFD); 2886 FunctionTemplate->setLexicalDeclContext(CurContext); 2887 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2888 } else { 2889 // This is a function template specialization. 2890 isFunctionTemplateSpecialization = true; 2891 } 2892 2893 // FIXME: Free this memory properly. 2894 TemplateParamLists.release(); 2895 } 2896 2897 // C++ [dcl.fct.spec]p5: 2898 // The virtual specifier shall only be used in declarations of 2899 // nonstatic class member functions that appear within a 2900 // member-specification of a class declaration; see 10.3. 2901 // 2902 if (isVirtual && !NewFD->isInvalidDecl()) { 2903 if (!isVirtualOkay) { 2904 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2905 diag::err_virtual_non_function); 2906 } else if (!CurContext->isRecord()) { 2907 // 'virtual' was specified outside of the class. 2908 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2909 << CodeModificationHint::CreateRemoval( 2910 D.getDeclSpec().getVirtualSpecLoc()); 2911 } else { 2912 // Okay: Add virtual to the method. 2913 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2914 CurClass->setMethodAsVirtual(NewFD); 2915 } 2916 } 2917 2918 // Filter out previous declarations that don't match the scope. 2919 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2920 2921 if (isFriend) { 2922 // DC is the namespace in which the function is being declared. 2923 assert((DC->isFileContext() || !Previous.empty()) && 2924 "previously-undeclared friend function being created " 2925 "in a non-namespace context"); 2926 2927 if (FunctionTemplate) { 2928 FunctionTemplate->setObjectOfFriendDecl( 2929 /* PreviouslyDeclared= */ !Previous.empty()); 2930 FunctionTemplate->setAccess(AS_public); 2931 } 2932 else 2933 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2934 2935 NewFD->setAccess(AS_public); 2936 } 2937 2938 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2939 !CurContext->isRecord()) { 2940 // C++ [class.static]p1: 2941 // A data or function member of a class may be declared static 2942 // in a class definition, in which case it is a static member of 2943 // the class. 2944 2945 // Complain about the 'static' specifier if it's on an out-of-line 2946 // member function definition. 2947 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2948 diag::err_static_out_of_line) 2949 << CodeModificationHint::CreateRemoval( 2950 D.getDeclSpec().getStorageClassSpecLoc()); 2951 } 2952 2953 // Handle GNU asm-label extension (encoded as an attribute). 2954 if (Expr *E = (Expr*) D.getAsmLabel()) { 2955 // The parser guarantees this is a string. 2956 StringLiteral *SE = cast<StringLiteral>(E); 2957 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2958 } 2959 2960 // Copy the parameter declarations from the declarator D to the function 2961 // declaration NewFD, if they are available. First scavenge them into Params. 2962 llvm::SmallVector<ParmVarDecl*, 16> Params; 2963 if (D.getNumTypeObjects() > 0) { 2964 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2965 2966 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2967 // function that takes no arguments, not a function that takes a 2968 // single void argument. 2969 // We let through "const void" here because Sema::GetTypeForDeclarator 2970 // already checks for that case. 2971 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2972 FTI.ArgInfo[0].Param && 2973 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2974 // Empty arg list, don't push any params. 2975 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2976 2977 // In C++, the empty parameter-type-list must be spelled "void"; a 2978 // typedef of void is not permitted. 2979 if (getLangOptions().CPlusPlus && 2980 Param->getType().getUnqualifiedType() != Context.VoidTy) 2981 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2982 // FIXME: Leaks decl? 2983 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2984 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2985 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2986 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2987 Param->setDeclContext(NewFD); 2988 Params.push_back(Param); 2989 } 2990 } 2991 2992 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2993 // When we're declaring a function with a typedef, typeof, etc as in the 2994 // following example, we'll need to synthesize (unnamed) 2995 // parameters for use in the declaration. 2996 // 2997 // @code 2998 // typedef void fn(int); 2999 // fn f; 3000 // @endcode 3001 3002 // Synthesize a parameter for each argument type. 3003 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3004 AE = FT->arg_type_end(); AI != AE; ++AI) { 3005 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 3006 SourceLocation(), 0, 3007 *AI, /*TInfo=*/0, 3008 VarDecl::None, 0); 3009 Param->setImplicit(); 3010 Params.push_back(Param); 3011 } 3012 } else { 3013 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3014 "Should not need args for typedef of non-prototype fn"); 3015 } 3016 // Finally, we know we have the right number of parameters, install them. 3017 NewFD->setParams(Context, Params.data(), Params.size()); 3018 3019 // If the declarator is a template-id, translate the parser's template 3020 // argument list into our AST format. 3021 bool HasExplicitTemplateArgs = false; 3022 TemplateArgumentListInfo TemplateArgs; 3023 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3024 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3025 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3026 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3027 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3028 TemplateId->getTemplateArgs(), 3029 TemplateId->NumArgs); 3030 translateTemplateArguments(TemplateArgsPtr, 3031 TemplateArgs); 3032 TemplateArgsPtr.release(); 3033 3034 HasExplicitTemplateArgs = true; 3035 3036 if (FunctionTemplate) { 3037 // FIXME: Diagnose function template with explicit template 3038 // arguments. 3039 HasExplicitTemplateArgs = false; 3040 } else if (!isFunctionTemplateSpecialization && 3041 !D.getDeclSpec().isFriendSpecified()) { 3042 // We have encountered something that the user meant to be a 3043 // specialization (because it has explicitly-specified template 3044 // arguments) but that was not introduced with a "template<>" (or had 3045 // too few of them). 3046 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3047 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3048 << CodeModificationHint::CreateInsertion( 3049 D.getDeclSpec().getSourceRange().getBegin(), 3050 "template<> "); 3051 isFunctionTemplateSpecialization = true; 3052 } 3053 } 3054 3055 if (isFunctionTemplateSpecialization) { 3056 if (CheckFunctionTemplateSpecialization(NewFD, 3057 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3058 Previous)) 3059 NewFD->setInvalidDecl(); 3060 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3061 CheckMemberSpecialization(NewFD, Previous)) 3062 NewFD->setInvalidDecl(); 3063 3064 // Perform semantic checking on the function declaration. 3065 bool OverloadableAttrRequired = false; // FIXME: HACK! 3066 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3067 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3068 3069 assert((NewFD->isInvalidDecl() || !Redeclaration || 3070 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3071 "previous declaration set still overloaded"); 3072 3073 // If we have a function template, check the template parameter 3074 // list. This will check and merge default template arguments. 3075 if (FunctionTemplate) { 3076 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3077 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3078 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3079 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3080 : TPC_FunctionTemplate); 3081 } 3082 3083 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3084 // An out-of-line member function declaration must also be a 3085 // definition (C++ [dcl.meaning]p1). 3086 // Note that this is not the case for explicit specializations of 3087 // function templates or member functions of class templates, per 3088 // C++ [temp.expl.spec]p2. 3089 if (!IsFunctionDefinition && !isFriend && 3090 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3091 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3092 << D.getCXXScopeSpec().getRange(); 3093 NewFD->setInvalidDecl(); 3094 } else if (!Redeclaration) { 3095 // The user tried to provide an out-of-line definition for a 3096 // function that is a member of a class or namespace, but there 3097 // was no such member function declared (C++ [class.mfct]p2, 3098 // C++ [namespace.memdef]p2). For example: 3099 // 3100 // class X { 3101 // void f() const; 3102 // }; 3103 // 3104 // void X::f() { } // ill-formed 3105 // 3106 // Complain about this problem, and attempt to suggest close 3107 // matches (e.g., those that differ only in cv-qualifiers and 3108 // whether the parameter types are references). 3109 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3110 << Name << DC << D.getCXXScopeSpec().getRange(); 3111 NewFD->setInvalidDecl(); 3112 3113 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3114 ForRedeclaration); 3115 LookupQualifiedName(Prev, DC); 3116 assert(!Prev.isAmbiguous() && 3117 "Cannot have an ambiguity in previous-declaration lookup"); 3118 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3119 Func != FuncEnd; ++Func) { 3120 if (isa<FunctionDecl>(*Func) && 3121 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3122 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3123 } 3124 } 3125 } 3126 3127 // Handle attributes. We need to have merged decls when handling attributes 3128 // (for example to check for conflicts, etc). 3129 // FIXME: This needs to happen before we merge declarations. Then, 3130 // let attribute merging cope with attribute conflicts. 3131 ProcessDeclAttributes(S, NewFD, D); 3132 3133 // attributes declared post-definition are currently ignored 3134 if (Redeclaration && Previous.isSingleResult()) { 3135 const FunctionDecl *Def; 3136 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3137 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3138 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3139 Diag(Def->getLocation(), diag::note_previous_definition); 3140 } 3141 } 3142 3143 AddKnownFunctionAttributes(NewFD); 3144 3145 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3146 // If a function name is overloadable in C, then every function 3147 // with that name must be marked "overloadable". 3148 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3149 << Redeclaration << NewFD; 3150 if (!Previous.empty()) 3151 Diag(Previous.getRepresentativeDecl()->getLocation(), 3152 diag::note_attribute_overloadable_prev_overload); 3153 NewFD->addAttr(::new (Context) OverloadableAttr()); 3154 } 3155 3156 // If this is a locally-scoped extern C function, update the 3157 // map of such names. 3158 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3159 && !NewFD->isInvalidDecl()) 3160 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3161 3162 // Set this FunctionDecl's range up to the right paren. 3163 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3164 3165 if (FunctionTemplate && NewFD->isInvalidDecl()) 3166 FunctionTemplate->setInvalidDecl(); 3167 3168 if (FunctionTemplate) 3169 return FunctionTemplate; 3170 3171 return NewFD; 3172} 3173 3174/// \brief Perform semantic checking of a new function declaration. 3175/// 3176/// Performs semantic analysis of the new function declaration 3177/// NewFD. This routine performs all semantic checking that does not 3178/// require the actual declarator involved in the declaration, and is 3179/// used both for the declaration of functions as they are parsed 3180/// (called via ActOnDeclarator) and for the declaration of functions 3181/// that have been instantiated via C++ template instantiation (called 3182/// via InstantiateDecl). 3183/// 3184/// \param IsExplicitSpecialiation whether this new function declaration is 3185/// an explicit specialization of the previous declaration. 3186/// 3187/// This sets NewFD->isInvalidDecl() to true if there was an error. 3188void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3189 LookupResult &Previous, 3190 bool IsExplicitSpecialization, 3191 bool &Redeclaration, 3192 bool &OverloadableAttrRequired) { 3193 // If NewFD is already known erroneous, don't do any of this checking. 3194 if (NewFD->isInvalidDecl()) 3195 return; 3196 3197 if (NewFD->getResultType()->isVariablyModifiedType()) { 3198 // Functions returning a variably modified type violate C99 6.7.5.2p2 3199 // because all functions have linkage. 3200 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3201 return NewFD->setInvalidDecl(); 3202 } 3203 3204 if (NewFD->isMain()) 3205 CheckMain(NewFD); 3206 3207 // Check for a previous declaration of this name. 3208 if (Previous.empty() && NewFD->isExternC()) { 3209 // Since we did not find anything by this name and we're declaring 3210 // an extern "C" function, look for a non-visible extern "C" 3211 // declaration with the same name. 3212 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3213 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3214 if (Pos != LocallyScopedExternalDecls.end()) 3215 Previous.addDecl(Pos->second); 3216 } 3217 3218 // Merge or overload the declaration with an existing declaration of 3219 // the same name, if appropriate. 3220 if (!Previous.empty()) { 3221 // Determine whether NewFD is an overload of PrevDecl or 3222 // a declaration that requires merging. If it's an overload, 3223 // there's no more work to do here; we'll just add the new 3224 // function to the scope. 3225 3226 NamedDecl *OldDecl = 0; 3227 if (!AllowOverloadingOfFunction(Previous, Context)) { 3228 Redeclaration = true; 3229 OldDecl = Previous.getFoundDecl(); 3230 } else { 3231 if (!getLangOptions().CPlusPlus) { 3232 OverloadableAttrRequired = true; 3233 3234 // Functions marked "overloadable" must have a prototype (that 3235 // we can't get through declaration merging). 3236 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3237 Diag(NewFD->getLocation(), 3238 diag::err_attribute_overloadable_no_prototype) 3239 << NewFD; 3240 Redeclaration = true; 3241 3242 // Turn this into a variadic function with no parameters. 3243 QualType R = Context.getFunctionType( 3244 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3245 0, 0, true, 0); 3246 NewFD->setType(R); 3247 return NewFD->setInvalidDecl(); 3248 } 3249 } 3250 3251 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3252 case Ovl_Match: 3253 Redeclaration = true; 3254 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3255 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3256 Redeclaration = false; 3257 } 3258 break; 3259 3260 case Ovl_NonFunction: 3261 Redeclaration = true; 3262 break; 3263 3264 case Ovl_Overload: 3265 Redeclaration = false; 3266 break; 3267 } 3268 } 3269 3270 if (Redeclaration) { 3271 // NewFD and OldDecl represent declarations that need to be 3272 // merged. 3273 if (MergeFunctionDecl(NewFD, OldDecl)) 3274 return NewFD->setInvalidDecl(); 3275 3276 Previous.clear(); 3277 Previous.addDecl(OldDecl); 3278 3279 if (FunctionTemplateDecl *OldTemplateDecl 3280 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3281 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3282 FunctionTemplateDecl *NewTemplateDecl 3283 = NewFD->getDescribedFunctionTemplate(); 3284 assert(NewTemplateDecl && "Template/non-template mismatch"); 3285 if (CXXMethodDecl *Method 3286 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3287 Method->setAccess(OldTemplateDecl->getAccess()); 3288 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3289 } 3290 3291 // If this is an explicit specialization of a member that is a function 3292 // template, mark it as a member specialization. 3293 if (IsExplicitSpecialization && 3294 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3295 NewTemplateDecl->setMemberSpecialization(); 3296 assert(OldTemplateDecl->isMemberSpecialization()); 3297 } 3298 } else { 3299 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3300 NewFD->setAccess(OldDecl->getAccess()); 3301 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3302 } 3303 } 3304 } 3305 3306 // Semantic checking for this function declaration (in isolation). 3307 if (getLangOptions().CPlusPlus) { 3308 // C++-specific checks. 3309 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3310 CheckConstructor(Constructor); 3311 } else if (CXXDestructorDecl *Destructor = 3312 dyn_cast<CXXDestructorDecl>(NewFD)) { 3313 CXXRecordDecl *Record = Destructor->getParent(); 3314 QualType ClassType = Context.getTypeDeclType(Record); 3315 3316 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3317 // type is dependent? Both gcc and edg can handle that. 3318 if (!ClassType->isDependentType()) { 3319 DeclarationName Name 3320 = Context.DeclarationNames.getCXXDestructorName( 3321 Context.getCanonicalType(ClassType)); 3322 if (NewFD->getDeclName() != Name) { 3323 Diag(NewFD->getLocation(), diag::err_destructor_name); 3324 return NewFD->setInvalidDecl(); 3325 } 3326 } 3327 3328 Record->setUserDeclaredDestructor(true); 3329 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3330 // user-defined destructor. 3331 Record->setPOD(false); 3332 3333 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3334 // declared destructor. 3335 // FIXME: C++0x: don't do this for "= default" destructors 3336 Record->setHasTrivialDestructor(false); 3337 } else if (CXXConversionDecl *Conversion 3338 = dyn_cast<CXXConversionDecl>(NewFD)) { 3339 ActOnConversionDeclarator(Conversion); 3340 } 3341 3342 // Find any virtual functions that this function overrides. 3343 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3344 if (!Method->isFunctionTemplateSpecialization() && 3345 !Method->getDescribedFunctionTemplate()) 3346 AddOverriddenMethods(Method->getParent(), Method); 3347 } 3348 3349 // Additional checks for the destructor; make sure we do this after we 3350 // figure out whether the destructor is virtual. 3351 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3352 if (!Destructor->getParent()->isDependentType()) 3353 CheckDestructor(Destructor); 3354 3355 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3356 if (NewFD->isOverloadedOperator() && 3357 CheckOverloadedOperatorDeclaration(NewFD)) 3358 return NewFD->setInvalidDecl(); 3359 3360 // In C++, check default arguments now that we have merged decls. Unless 3361 // the lexical context is the class, because in this case this is done 3362 // during delayed parsing anyway. 3363 if (!CurContext->isRecord()) 3364 CheckCXXDefaultArguments(NewFD); 3365 } 3366} 3367 3368void Sema::CheckMain(FunctionDecl* FD) { 3369 // C++ [basic.start.main]p3: A program that declares main to be inline 3370 // or static is ill-formed. 3371 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3372 // shall not appear in a declaration of main. 3373 // static main is not an error under C99, but we should warn about it. 3374 bool isInline = FD->isInlineSpecified(); 3375 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3376 if (isInline || isStatic) { 3377 unsigned diagID = diag::warn_unusual_main_decl; 3378 if (isInline || getLangOptions().CPlusPlus) 3379 diagID = diag::err_unusual_main_decl; 3380 3381 int which = isStatic + (isInline << 1) - 1; 3382 Diag(FD->getLocation(), diagID) << which; 3383 } 3384 3385 QualType T = FD->getType(); 3386 assert(T->isFunctionType() && "function decl is not of function type"); 3387 const FunctionType* FT = T->getAs<FunctionType>(); 3388 3389 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3390 // TODO: add a replacement fixit to turn the return type into 'int'. 3391 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3392 FD->setInvalidDecl(true); 3393 } 3394 3395 // Treat protoless main() as nullary. 3396 if (isa<FunctionNoProtoType>(FT)) return; 3397 3398 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3399 unsigned nparams = FTP->getNumArgs(); 3400 assert(FD->getNumParams() == nparams); 3401 3402 bool HasExtraParameters = (nparams > 3); 3403 3404 // Darwin passes an undocumented fourth argument of type char**. If 3405 // other platforms start sprouting these, the logic below will start 3406 // getting shifty. 3407 if (nparams == 4 && 3408 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3409 HasExtraParameters = false; 3410 3411 if (HasExtraParameters) { 3412 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3413 FD->setInvalidDecl(true); 3414 nparams = 3; 3415 } 3416 3417 // FIXME: a lot of the following diagnostics would be improved 3418 // if we had some location information about types. 3419 3420 QualType CharPP = 3421 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3422 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3423 3424 for (unsigned i = 0; i < nparams; ++i) { 3425 QualType AT = FTP->getArgType(i); 3426 3427 bool mismatch = true; 3428 3429 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3430 mismatch = false; 3431 else if (Expected[i] == CharPP) { 3432 // As an extension, the following forms are okay: 3433 // char const ** 3434 // char const * const * 3435 // char * const * 3436 3437 QualifierCollector qs; 3438 const PointerType* PT; 3439 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3440 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3441 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3442 qs.removeConst(); 3443 mismatch = !qs.empty(); 3444 } 3445 } 3446 3447 if (mismatch) { 3448 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3449 // TODO: suggest replacing given type with expected type 3450 FD->setInvalidDecl(true); 3451 } 3452 } 3453 3454 if (nparams == 1 && !FD->isInvalidDecl()) { 3455 Diag(FD->getLocation(), diag::warn_main_one_arg); 3456 } 3457} 3458 3459bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3460 // FIXME: Need strict checking. In C89, we need to check for 3461 // any assignment, increment, decrement, function-calls, or 3462 // commas outside of a sizeof. In C99, it's the same list, 3463 // except that the aforementioned are allowed in unevaluated 3464 // expressions. Everything else falls under the 3465 // "may accept other forms of constant expressions" exception. 3466 // (We never end up here for C++, so the constant expression 3467 // rules there don't matter.) 3468 if (Init->isConstantInitializer(Context)) 3469 return false; 3470 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3471 << Init->getSourceRange(); 3472 return true; 3473} 3474 3475void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3476 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3477} 3478 3479/// AddInitializerToDecl - Adds the initializer Init to the 3480/// declaration dcl. If DirectInit is true, this is C++ direct 3481/// initialization rather than copy initialization. 3482void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3483 Decl *RealDecl = dcl.getAs<Decl>(); 3484 // If there is no declaration, there was an error parsing it. Just ignore 3485 // the initializer. 3486 if (RealDecl == 0) 3487 return; 3488 3489 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3490 // With declarators parsed the way they are, the parser cannot 3491 // distinguish between a normal initializer and a pure-specifier. 3492 // Thus this grotesque test. 3493 IntegerLiteral *IL; 3494 Expr *Init = static_cast<Expr *>(init.get()); 3495 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3496 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3497 CheckPureMethod(Method, Init->getSourceRange()); 3498 else { 3499 Diag(Method->getLocation(), diag::err_member_function_initialization) 3500 << Method->getDeclName() << Init->getSourceRange(); 3501 Method->setInvalidDecl(); 3502 } 3503 return; 3504 } 3505 3506 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3507 if (!VDecl) { 3508 if (getLangOptions().CPlusPlus && 3509 RealDecl->getLexicalDeclContext()->isRecord() && 3510 isa<NamedDecl>(RealDecl)) 3511 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3512 << cast<NamedDecl>(RealDecl)->getDeclName(); 3513 else 3514 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3515 RealDecl->setInvalidDecl(); 3516 return; 3517 } 3518 3519 // A definition must end up with a complete type, which means it must be 3520 // complete with the restriction that an array type might be completed by the 3521 // initializer; note that later code assumes this restriction. 3522 QualType BaseDeclType = VDecl->getType(); 3523 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3524 BaseDeclType = Array->getElementType(); 3525 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3526 diag::err_typecheck_decl_incomplete_type)) { 3527 RealDecl->setInvalidDecl(); 3528 return; 3529 } 3530 3531 // The variable can not have an abstract class type. 3532 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3533 diag::err_abstract_type_in_decl, 3534 AbstractVariableType)) 3535 VDecl->setInvalidDecl(); 3536 3537 const VarDecl *Def = 0; 3538 if (VDecl->getDefinition(Def)) { 3539 Diag(VDecl->getLocation(), diag::err_redefinition) 3540 << VDecl->getDeclName(); 3541 Diag(Def->getLocation(), diag::note_previous_definition); 3542 VDecl->setInvalidDecl(); 3543 return; 3544 } 3545 3546 // Take ownership of the expression, now that we're sure we have somewhere 3547 // to put it. 3548 Expr *Init = init.takeAs<Expr>(); 3549 assert(Init && "missing initializer"); 3550 3551 // Capture the variable that is being initialized and the style of 3552 // initialization. 3553 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3554 3555 // FIXME: Poor source location information. 3556 InitializationKind Kind 3557 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3558 Init->getLocStart(), 3559 Init->getLocEnd()) 3560 : InitializationKind::CreateCopy(VDecl->getLocation(), 3561 Init->getLocStart()); 3562 3563 // Get the decls type and save a reference for later, since 3564 // CheckInitializerTypes may change it. 3565 QualType DclT = VDecl->getType(), SavT = DclT; 3566 if (VDecl->isBlockVarDecl()) { 3567 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3568 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3569 VDecl->setInvalidDecl(); 3570 } else if (!VDecl->isInvalidDecl()) { 3571 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3572 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3573 MultiExprArg(*this, (void**)&Init, 1), 3574 &DclT); 3575 if (Result.isInvalid()) { 3576 VDecl->setInvalidDecl(); 3577 return; 3578 } 3579 3580 Init = Result.takeAs<Expr>(); 3581 3582 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3583 // Don't check invalid declarations to avoid emitting useless diagnostics. 3584 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3585 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3586 CheckForConstantInitializer(Init, DclT); 3587 } 3588 } 3589 } else if (VDecl->isStaticDataMember() && 3590 VDecl->getLexicalDeclContext()->isRecord()) { 3591 // This is an in-class initialization for a static data member, e.g., 3592 // 3593 // struct S { 3594 // static const int value = 17; 3595 // }; 3596 3597 // Attach the initializer 3598 VDecl->setInit(Context, Init); 3599 3600 // C++ [class.mem]p4: 3601 // A member-declarator can contain a constant-initializer only 3602 // if it declares a static member (9.4) of const integral or 3603 // const enumeration type, see 9.4.2. 3604 QualType T = VDecl->getType(); 3605 if (!T->isDependentType() && 3606 (!Context.getCanonicalType(T).isConstQualified() || 3607 !T->isIntegralType())) { 3608 Diag(VDecl->getLocation(), diag::err_member_initialization) 3609 << VDecl->getDeclName() << Init->getSourceRange(); 3610 VDecl->setInvalidDecl(); 3611 } else { 3612 // C++ [class.static.data]p4: 3613 // If a static data member is of const integral or const 3614 // enumeration type, its declaration in the class definition 3615 // can specify a constant-initializer which shall be an 3616 // integral constant expression (5.19). 3617 if (!Init->isTypeDependent() && 3618 !Init->getType()->isIntegralType()) { 3619 // We have a non-dependent, non-integral or enumeration type. 3620 Diag(Init->getSourceRange().getBegin(), 3621 diag::err_in_class_initializer_non_integral_type) 3622 << Init->getType() << Init->getSourceRange(); 3623 VDecl->setInvalidDecl(); 3624 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3625 // Check whether the expression is a constant expression. 3626 llvm::APSInt Value; 3627 SourceLocation Loc; 3628 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3629 Diag(Loc, diag::err_in_class_initializer_non_constant) 3630 << Init->getSourceRange(); 3631 VDecl->setInvalidDecl(); 3632 } else if (!VDecl->getType()->isDependentType()) 3633 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3634 } 3635 } 3636 } else if (VDecl->isFileVarDecl()) { 3637 if (VDecl->getStorageClass() == VarDecl::Extern) 3638 Diag(VDecl->getLocation(), diag::warn_extern_init); 3639 if (!VDecl->isInvalidDecl()) { 3640 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3641 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3642 MultiExprArg(*this, (void**)&Init, 1), 3643 &DclT); 3644 if (Result.isInvalid()) { 3645 VDecl->setInvalidDecl(); 3646 return; 3647 } 3648 3649 Init = Result.takeAs<Expr>(); 3650 } 3651 3652 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3653 // Don't check invalid declarations to avoid emitting useless diagnostics. 3654 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3655 // C99 6.7.8p4. All file scoped initializers need to be constant. 3656 CheckForConstantInitializer(Init, DclT); 3657 } 3658 } 3659 // If the type changed, it means we had an incomplete type that was 3660 // completed by the initializer. For example: 3661 // int ary[] = { 1, 3, 5 }; 3662 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3663 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3664 VDecl->setType(DclT); 3665 Init->setType(DclT); 3666 } 3667 3668 Init = MaybeCreateCXXExprWithTemporaries(Init); 3669 // Attach the initializer to the decl. 3670 VDecl->setInit(Context, Init); 3671 3672 // If the previous declaration of VDecl was a tentative definition, 3673 // remove it from the set of tentative definitions. 3674 if (VDecl->getPreviousDeclaration() && 3675 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3676 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3677 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3678 } 3679 3680 if (getLangOptions().CPlusPlus) { 3681 // Make sure we mark the destructor as used if necessary. 3682 QualType InitType = VDecl->getType(); 3683 if (const ArrayType *Array = Context.getAsArrayType(InitType)) 3684 InitType = Context.getBaseElementType(Array); 3685 if (InitType->isRecordType()) 3686 FinalizeVarWithDestructor(VDecl, InitType); 3687 } 3688 3689 return; 3690} 3691 3692void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3693 bool TypeContainsUndeducedAuto) { 3694 Decl *RealDecl = dcl.getAs<Decl>(); 3695 3696 // If there is no declaration, there was an error parsing it. Just ignore it. 3697 if (RealDecl == 0) 3698 return; 3699 3700 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3701 QualType Type = Var->getType(); 3702 3703 // Record tentative definitions. 3704 if (Var->isTentativeDefinition(Context)) { 3705 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3706 InsertPair = 3707 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3708 3709 // Keep the latest definition in the map. If we see 'int i; int i;' we 3710 // want the second one in the map. 3711 InsertPair.first->second = Var; 3712 3713 // However, for the list, we don't care about the order, just make sure 3714 // that there are no dupes for a given declaration name. 3715 if (InsertPair.second) 3716 TentativeDefinitionList.push_back(Var->getDeclName()); 3717 } 3718 3719 // C++ [dcl.init.ref]p3: 3720 // The initializer can be omitted for a reference only in a 3721 // parameter declaration (8.3.5), in the declaration of a 3722 // function return type, in the declaration of a class member 3723 // within its class declaration (9.2), and where the extern 3724 // specifier is explicitly used. 3725 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3726 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3727 << Var->getDeclName() 3728 << SourceRange(Var->getLocation(), Var->getLocation()); 3729 Var->setInvalidDecl(); 3730 return; 3731 } 3732 3733 // C++0x [dcl.spec.auto]p3 3734 if (TypeContainsUndeducedAuto) { 3735 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3736 << Var->getDeclName() << Type; 3737 Var->setInvalidDecl(); 3738 return; 3739 } 3740 3741 // An array without size is an incomplete type, and there are no special 3742 // rules in C++ to make such a definition acceptable. 3743 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3744 !Var->hasExternalStorage()) { 3745 Diag(Var->getLocation(), 3746 diag::err_typecheck_incomplete_array_needs_initializer); 3747 Var->setInvalidDecl(); 3748 return; 3749 } 3750 3751 // C++ [temp.expl.spec]p15: 3752 // An explicit specialization of a static data member of a template is a 3753 // definition if the declaration includes an initializer; otherwise, it 3754 // is a declaration. 3755 if (Var->isStaticDataMember() && 3756 Var->getInstantiatedFromStaticDataMember() && 3757 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3758 return; 3759 3760 // C++ [dcl.init]p9: 3761 // If no initializer is specified for an object, and the object 3762 // is of (possibly cv-qualified) non-POD class type (or array 3763 // thereof), the object shall be default-initialized; if the 3764 // object is of const-qualified type, the underlying class type 3765 // shall have a user-declared default constructor. 3766 // 3767 // FIXME: Diagnose the "user-declared default constructor" bit. 3768 if (getLangOptions().CPlusPlus) { 3769 QualType InitType = Type; 3770 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3771 InitType = Context.getBaseElementType(Array); 3772 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3773 InitType->isRecordType() && !InitType->isDependentType()) { 3774 if (!RequireCompleteType(Var->getLocation(), InitType, 3775 diag::err_invalid_incomplete_type_use)) { 3776 InitializedEntity Entity 3777 = InitializedEntity::InitializeVariable(Var); 3778 InitializationKind Kind 3779 = InitializationKind::CreateDefault(Var->getLocation()); 3780 3781 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 3782 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 3783 MultiExprArg(*this, 0, 0)); 3784 if (Init.isInvalid()) 3785 Var->setInvalidDecl(); 3786 else { 3787 Var->setInit(Context, 3788 MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 3789 FinalizeVarWithDestructor(Var, InitType); 3790 } 3791 } else { 3792 Var->setInvalidDecl(); 3793 } 3794 } 3795 3796 // The variable can not have an abstract class type. 3797 if (RequireNonAbstractType(Var->getLocation(), Type, 3798 diag::err_abstract_type_in_decl, 3799 AbstractVariableType)) 3800 Var->setInvalidDecl(); 3801 } 3802 3803#if 0 3804 // FIXME: Temporarily disabled because we are not properly parsing 3805 // linkage specifications on declarations, e.g., 3806 // 3807 // extern "C" const CGPoint CGPointerZero; 3808 // 3809 // C++ [dcl.init]p9: 3810 // 3811 // If no initializer is specified for an object, and the 3812 // object is of (possibly cv-qualified) non-POD class type (or 3813 // array thereof), the object shall be default-initialized; if 3814 // the object is of const-qualified type, the underlying class 3815 // type shall have a user-declared default 3816 // constructor. Otherwise, if no initializer is specified for 3817 // an object, the object and its subobjects, if any, have an 3818 // indeterminate initial value; if the object or any of its 3819 // subobjects are of const-qualified type, the program is 3820 // ill-formed. 3821 // 3822 // This isn't technically an error in C, so we don't diagnose it. 3823 // 3824 // FIXME: Actually perform the POD/user-defined default 3825 // constructor check. 3826 if (getLangOptions().CPlusPlus && 3827 Context.getCanonicalType(Type).isConstQualified() && 3828 !Var->hasExternalStorage()) 3829 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3830 << Var->getName() 3831 << SourceRange(Var->getLocation(), Var->getLocation()); 3832#endif 3833 } 3834} 3835 3836Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3837 DeclPtrTy *Group, 3838 unsigned NumDecls) { 3839 llvm::SmallVector<Decl*, 8> Decls; 3840 3841 if (DS.isTypeSpecOwned()) 3842 Decls.push_back((Decl*)DS.getTypeRep()); 3843 3844 for (unsigned i = 0; i != NumDecls; ++i) 3845 if (Decl *D = Group[i].getAs<Decl>()) 3846 Decls.push_back(D); 3847 3848 // Perform semantic analysis that depends on having fully processed both 3849 // the declarator and initializer. 3850 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3851 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3852 if (!IDecl) 3853 continue; 3854 QualType T = IDecl->getType(); 3855 3856 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3857 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3858 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3859 if (T->isDependentType()) { 3860 // If T is dependent, we should not require a complete type. 3861 // (RequireCompleteType shouldn't be called with dependent types.) 3862 // But we still can at least check if we've got an array of unspecified 3863 // size without an initializer. 3864 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3865 !IDecl->getInit()) { 3866 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3867 << T; 3868 IDecl->setInvalidDecl(); 3869 } 3870 } else if (!IDecl->isInvalidDecl()) { 3871 // If T is an incomplete array type with an initializer list that is 3872 // dependent on something, its size has not been fixed. We could attempt 3873 // to fix the size for such arrays, but we would still have to check 3874 // here for initializers containing a C++0x vararg expansion, e.g. 3875 // template <typename... Args> void f(Args... args) { 3876 // int vals[] = { args }; 3877 // } 3878 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3879 Expr *Init = IDecl->getInit(); 3880 if (IAT && Init && 3881 (Init->isTypeDependent() || Init->isValueDependent())) { 3882 // Check that the member type of the array is complete, at least. 3883 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3884 diag::err_typecheck_decl_incomplete_type)) 3885 IDecl->setInvalidDecl(); 3886 } else if (RequireCompleteType(IDecl->getLocation(), T, 3887 diag::err_typecheck_decl_incomplete_type)) 3888 IDecl->setInvalidDecl(); 3889 } 3890 } 3891 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3892 // object that has file scope without an initializer, and without a 3893 // storage-class specifier or with the storage-class specifier "static", 3894 // constitutes a tentative definition. Note: A tentative definition with 3895 // external linkage is valid (C99 6.2.2p5). 3896 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3897 if (const IncompleteArrayType *ArrayT 3898 = Context.getAsIncompleteArrayType(T)) { 3899 if (RequireCompleteType(IDecl->getLocation(), 3900 ArrayT->getElementType(), 3901 diag::err_illegal_decl_array_incomplete_type)) 3902 IDecl->setInvalidDecl(); 3903 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3904 // C99 6.9.2p3: If the declaration of an identifier for an object is 3905 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3906 // declared type shall not be an incomplete type. 3907 // NOTE: code such as the following 3908 // static struct s; 3909 // struct s { int a; }; 3910 // is accepted by gcc. Hence here we issue a warning instead of 3911 // an error and we do not invalidate the static declaration. 3912 // NOTE: to avoid multiple warnings, only check the first declaration. 3913 if (IDecl->getPreviousDeclaration() == 0) 3914 RequireCompleteType(IDecl->getLocation(), T, 3915 diag::ext_typecheck_decl_incomplete_type); 3916 } 3917 } 3918 } 3919 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3920 Decls.data(), Decls.size())); 3921} 3922 3923 3924/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3925/// to introduce parameters into function prototype scope. 3926Sema::DeclPtrTy 3927Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3928 const DeclSpec &DS = D.getDeclSpec(); 3929 3930 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3931 VarDecl::StorageClass StorageClass = VarDecl::None; 3932 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3933 StorageClass = VarDecl::Register; 3934 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3935 Diag(DS.getStorageClassSpecLoc(), 3936 diag::err_invalid_storage_class_in_func_decl); 3937 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3938 } 3939 3940 if (D.getDeclSpec().isThreadSpecified()) 3941 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3942 3943 DiagnoseFunctionSpecifiers(D); 3944 3945 // Check that there are no default arguments inside the type of this 3946 // parameter (C++ only). 3947 if (getLangOptions().CPlusPlus) 3948 CheckExtraCXXDefaultArguments(D); 3949 3950 TypeSourceInfo *TInfo = 0; 3951 TagDecl *OwnedDecl = 0; 3952 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3953 3954 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3955 // C++ [dcl.fct]p6: 3956 // Types shall not be defined in return or parameter types. 3957 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3958 << Context.getTypeDeclType(OwnedDecl); 3959 } 3960 3961 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3962 // Can this happen for params? We already checked that they don't conflict 3963 // among each other. Here they can only shadow globals, which is ok. 3964 IdentifierInfo *II = D.getIdentifier(); 3965 if (II) { 3966 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3967 if (PrevDecl->isTemplateParameter()) { 3968 // Maybe we will complain about the shadowed template parameter. 3969 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3970 // Just pretend that we didn't see the previous declaration. 3971 PrevDecl = 0; 3972 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3973 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3974 3975 // Recover by removing the name 3976 II = 0; 3977 D.SetIdentifier(0, D.getIdentifierLoc()); 3978 } 3979 } 3980 } 3981 3982 // Parameters can not be abstract class types. 3983 // For record types, this is done by the AbstractClassUsageDiagnoser once 3984 // the class has been completely parsed. 3985 if (!CurContext->isRecord() && 3986 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3987 diag::err_abstract_type_in_decl, 3988 AbstractParamType)) 3989 D.setInvalidType(true); 3990 3991 QualType T = adjustParameterType(parmDeclType); 3992 3993 ParmVarDecl *New 3994 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3995 T, TInfo, StorageClass, 0); 3996 3997 if (D.isInvalidType()) 3998 New->setInvalidDecl(); 3999 4000 // Parameter declarators cannot be interface types. All ObjC objects are 4001 // passed by reference. 4002 if (T->isObjCInterfaceType()) { 4003 Diag(D.getIdentifierLoc(), 4004 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4005 New->setInvalidDecl(); 4006 } 4007 4008 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4009 if (D.getCXXScopeSpec().isSet()) { 4010 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4011 << D.getCXXScopeSpec().getRange(); 4012 New->setInvalidDecl(); 4013 } 4014 4015 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4016 // duration shall not be qualified by an address-space qualifier." 4017 // Since all parameters have automatic store duration, they can not have 4018 // an address space. 4019 if (T.getAddressSpace() != 0) { 4020 Diag(D.getIdentifierLoc(), 4021 diag::err_arg_with_address_space); 4022 New->setInvalidDecl(); 4023 } 4024 4025 4026 // Add the parameter declaration into this scope. 4027 S->AddDecl(DeclPtrTy::make(New)); 4028 if (II) 4029 IdResolver.AddDecl(New); 4030 4031 ProcessDeclAttributes(S, New, D); 4032 4033 if (New->hasAttr<BlocksAttr>()) { 4034 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4035 } 4036 return DeclPtrTy::make(New); 4037} 4038 4039void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4040 SourceLocation LocAfterDecls) { 4041 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4042 "Not a function declarator!"); 4043 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4044 4045 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4046 // for a K&R function. 4047 if (!FTI.hasPrototype) { 4048 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4049 --i; 4050 if (FTI.ArgInfo[i].Param == 0) { 4051 llvm::SmallString<256> Code; 4052 llvm::raw_svector_ostream(Code) << " int " 4053 << FTI.ArgInfo[i].Ident->getName() 4054 << ";\n"; 4055 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4056 << FTI.ArgInfo[i].Ident 4057 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4058 4059 // Implicitly declare the argument as type 'int' for lack of a better 4060 // type. 4061 DeclSpec DS; 4062 const char* PrevSpec; // unused 4063 unsigned DiagID; // unused 4064 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4065 PrevSpec, DiagID); 4066 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4067 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4068 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4069 } 4070 } 4071 } 4072} 4073 4074Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4075 Declarator &D) { 4076 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4077 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4078 "Not a function declarator!"); 4079 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4080 4081 if (FTI.hasPrototype) { 4082 // FIXME: Diagnose arguments without names in C. 4083 } 4084 4085 Scope *ParentScope = FnBodyScope->getParent(); 4086 4087 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4088 MultiTemplateParamsArg(*this), 4089 /*IsFunctionDefinition=*/true); 4090 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4091} 4092 4093static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4094 // Don't warn about invalid declarations. 4095 if (FD->isInvalidDecl()) 4096 return false; 4097 4098 // Or declarations that aren't global. 4099 if (!FD->isGlobal()) 4100 return false; 4101 4102 // Don't warn about C++ member functions. 4103 if (isa<CXXMethodDecl>(FD)) 4104 return false; 4105 4106 // Don't warn about 'main'. 4107 if (FD->isMain()) 4108 return false; 4109 4110 // Don't warn about inline functions. 4111 if (FD->isInlineSpecified()) 4112 return false; 4113 4114 // Don't warn about function templates. 4115 if (FD->getDescribedFunctionTemplate()) 4116 return false; 4117 4118 // Don't warn about function template specializations. 4119 if (FD->isFunctionTemplateSpecialization()) 4120 return false; 4121 4122 bool MissingPrototype = true; 4123 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4124 Prev; Prev = Prev->getPreviousDeclaration()) { 4125 // Ignore any declarations that occur in function or method 4126 // scope, because they aren't visible from the header. 4127 if (Prev->getDeclContext()->isFunctionOrMethod()) 4128 continue; 4129 4130 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4131 break; 4132 } 4133 4134 return MissingPrototype; 4135} 4136 4137Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4138 // Clear the last template instantiation error context. 4139 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4140 4141 if (!D) 4142 return D; 4143 FunctionDecl *FD = 0; 4144 4145 if (FunctionTemplateDecl *FunTmpl 4146 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4147 FD = FunTmpl->getTemplatedDecl(); 4148 else 4149 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4150 4151 CurFunctionNeedsScopeChecking = false; 4152 4153 // See if this is a redefinition. 4154 const FunctionDecl *Definition; 4155 if (FD->getBody(Definition)) { 4156 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4157 Diag(Definition->getLocation(), diag::note_previous_definition); 4158 } 4159 4160 // Builtin functions cannot be defined. 4161 if (unsigned BuiltinID = FD->getBuiltinID()) { 4162 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4163 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4164 FD->setInvalidDecl(); 4165 } 4166 } 4167 4168 // The return type of a function definition must be complete 4169 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4170 QualType ResultType = FD->getResultType(); 4171 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4172 !FD->isInvalidDecl() && 4173 RequireCompleteType(FD->getLocation(), ResultType, 4174 diag::err_func_def_incomplete_result)) 4175 FD->setInvalidDecl(); 4176 4177 // GNU warning -Wmissing-prototypes: 4178 // Warn if a global function is defined without a previous 4179 // prototype declaration. This warning is issued even if the 4180 // definition itself provides a prototype. The aim is to detect 4181 // global functions that fail to be declared in header files. 4182 if (ShouldWarnAboutMissingPrototype(FD)) 4183 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4184 4185 if (FnBodyScope) 4186 PushDeclContext(FnBodyScope, FD); 4187 4188 // Check the validity of our function parameters 4189 CheckParmsForFunctionDef(FD); 4190 4191 // Introduce our parameters into the function scope 4192 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4193 ParmVarDecl *Param = FD->getParamDecl(p); 4194 Param->setOwningFunction(FD); 4195 4196 // If this has an identifier, add it to the scope stack. 4197 if (Param->getIdentifier() && FnBodyScope) 4198 PushOnScopeChains(Param, FnBodyScope); 4199 } 4200 4201 // Checking attributes of current function definition 4202 // dllimport attribute. 4203 if (FD->getAttr<DLLImportAttr>() && 4204 (!FD->getAttr<DLLExportAttr>())) { 4205 // dllimport attribute cannot be applied to definition. 4206 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4207 Diag(FD->getLocation(), 4208 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4209 << "dllimport"; 4210 FD->setInvalidDecl(); 4211 return DeclPtrTy::make(FD); 4212 } else { 4213 // If a symbol previously declared dllimport is later defined, the 4214 // attribute is ignored in subsequent references, and a warning is 4215 // emitted. 4216 Diag(FD->getLocation(), 4217 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4218 << FD->getNameAsCString() << "dllimport"; 4219 } 4220 } 4221 return DeclPtrTy::make(FD); 4222} 4223 4224Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4225 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4226} 4227 4228Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4229 bool IsInstantiation) { 4230 Decl *dcl = D.getAs<Decl>(); 4231 Stmt *Body = BodyArg.takeAs<Stmt>(); 4232 4233 FunctionDecl *FD = 0; 4234 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4235 if (FunTmpl) 4236 FD = FunTmpl->getTemplatedDecl(); 4237 else 4238 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4239 4240 if (FD) { 4241 FD->setBody(Body); 4242 if (FD->isMain()) 4243 // C and C++ allow for main to automagically return 0. 4244 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4245 FD->setHasImplicitReturnZero(true); 4246 else 4247 CheckFallThroughForFunctionDef(FD, Body); 4248 4249 if (!FD->isInvalidDecl()) 4250 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4251 4252 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4253 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4254 4255 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4256 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4257 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4258 MD->setBody(Body); 4259 CheckFallThroughForFunctionDef(MD, Body); 4260 MD->setEndLoc(Body->getLocEnd()); 4261 4262 if (!MD->isInvalidDecl()) 4263 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4264 } else { 4265 Body->Destroy(Context); 4266 return DeclPtrTy(); 4267 } 4268 if (!IsInstantiation) 4269 PopDeclContext(); 4270 4271 // Verify and clean out per-function state. 4272 4273 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4274 4275 // Check goto/label use. 4276 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4277 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4278 LabelStmt *L = I->second; 4279 4280 // Verify that we have no forward references left. If so, there was a goto 4281 // or address of a label taken, but no definition of it. Label fwd 4282 // definitions are indicated with a null substmt. 4283 if (L->getSubStmt() != 0) 4284 continue; 4285 4286 // Emit error. 4287 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4288 4289 // At this point, we have gotos that use the bogus label. Stitch it into 4290 // the function body so that they aren't leaked and that the AST is well 4291 // formed. 4292 if (Body == 0) { 4293 // The whole function wasn't parsed correctly, just delete this. 4294 L->Destroy(Context); 4295 continue; 4296 } 4297 4298 // Otherwise, the body is valid: we want to stitch the label decl into the 4299 // function somewhere so that it is properly owned and so that the goto 4300 // has a valid target. Do this by creating a new compound stmt with the 4301 // label in it. 4302 4303 // Give the label a sub-statement. 4304 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4305 4306 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4307 cast<CXXTryStmt>(Body)->getTryBlock() : 4308 cast<CompoundStmt>(Body); 4309 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4310 Elements.push_back(L); 4311 Compound->setStmts(Context, &Elements[0], Elements.size()); 4312 } 4313 FunctionLabelMap.clear(); 4314 4315 if (!Body) return D; 4316 4317 // Verify that that gotos and switch cases don't jump into scopes illegally. 4318 if (CurFunctionNeedsScopeChecking) 4319 DiagnoseInvalidJumps(Body); 4320 4321 // C++ constructors that have function-try-blocks can't have return 4322 // statements in the handlers of that block. (C++ [except.handle]p14) 4323 // Verify this. 4324 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4325 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4326 4327 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4328 MarkBaseAndMemberDestructorsReferenced(Destructor); 4329 4330 // If any errors have occurred, clear out any temporaries that may have 4331 // been leftover. This ensures that these temporaries won't be picked up for 4332 // deletion in some later function. 4333 if (PP.getDiagnostics().hasErrorOccurred()) 4334 ExprTemporaries.clear(); 4335 4336 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4337 return D; 4338} 4339 4340/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4341/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4342NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4343 IdentifierInfo &II, Scope *S) { 4344 // Before we produce a declaration for an implicitly defined 4345 // function, see whether there was a locally-scoped declaration of 4346 // this name as a function or variable. If so, use that 4347 // (non-visible) declaration, and complain about it. 4348 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4349 = LocallyScopedExternalDecls.find(&II); 4350 if (Pos != LocallyScopedExternalDecls.end()) { 4351 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4352 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4353 return Pos->second; 4354 } 4355 4356 // Extension in C99. Legal in C90, but warn about it. 4357 if (II.getName().startswith("__builtin_")) 4358 Diag(Loc, diag::warn_builtin_unknown) << &II; 4359 else if (getLangOptions().C99) 4360 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4361 else 4362 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4363 4364 // Set a Declarator for the implicit definition: int foo(); 4365 const char *Dummy; 4366 DeclSpec DS; 4367 unsigned DiagID; 4368 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4369 Error = Error; // Silence warning. 4370 assert(!Error && "Error setting up implicit decl!"); 4371 Declarator D(DS, Declarator::BlockContext); 4372 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4373 0, 0, false, SourceLocation(), 4374 false, 0,0,0, Loc, Loc, D), 4375 SourceLocation()); 4376 D.SetIdentifier(&II, Loc); 4377 4378 // Insert this function into translation-unit scope. 4379 4380 DeclContext *PrevDC = CurContext; 4381 CurContext = Context.getTranslationUnitDecl(); 4382 4383 FunctionDecl *FD = 4384 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4385 FD->setImplicit(); 4386 4387 CurContext = PrevDC; 4388 4389 AddKnownFunctionAttributes(FD); 4390 4391 return FD; 4392} 4393 4394/// \brief Adds any function attributes that we know a priori based on 4395/// the declaration of this function. 4396/// 4397/// These attributes can apply both to implicitly-declared builtins 4398/// (like __builtin___printf_chk) or to library-declared functions 4399/// like NSLog or printf. 4400void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4401 if (FD->isInvalidDecl()) 4402 return; 4403 4404 // If this is a built-in function, map its builtin attributes to 4405 // actual attributes. 4406 if (unsigned BuiltinID = FD->getBuiltinID()) { 4407 // Handle printf-formatting attributes. 4408 unsigned FormatIdx; 4409 bool HasVAListArg; 4410 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4411 if (!FD->getAttr<FormatAttr>()) 4412 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4413 HasVAListArg ? 0 : FormatIdx + 2)); 4414 } 4415 4416 // Mark const if we don't care about errno and that is the only 4417 // thing preventing the function from being const. This allows 4418 // IRgen to use LLVM intrinsics for such functions. 4419 if (!getLangOptions().MathErrno && 4420 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4421 if (!FD->getAttr<ConstAttr>()) 4422 FD->addAttr(::new (Context) ConstAttr()); 4423 } 4424 4425 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4426 FD->addAttr(::new (Context) NoReturnAttr()); 4427 } 4428 4429 IdentifierInfo *Name = FD->getIdentifier(); 4430 if (!Name) 4431 return; 4432 if ((!getLangOptions().CPlusPlus && 4433 FD->getDeclContext()->isTranslationUnit()) || 4434 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4435 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4436 LinkageSpecDecl::lang_c)) { 4437 // Okay: this could be a libc/libm/Objective-C function we know 4438 // about. 4439 } else 4440 return; 4441 4442 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4443 // FIXME: NSLog and NSLogv should be target specific 4444 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4445 // FIXME: We known better than our headers. 4446 const_cast<FormatAttr *>(Format)->setType("printf"); 4447 } else 4448 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4449 Name->isStr("NSLogv") ? 0 : 2)); 4450 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4451 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4452 // target-specific builtins, perhaps? 4453 if (!FD->getAttr<FormatAttr>()) 4454 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4455 Name->isStr("vasprintf") ? 0 : 3)); 4456 } 4457} 4458 4459TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4460 TypeSourceInfo *TInfo) { 4461 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4462 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4463 4464 if (!TInfo) { 4465 assert(D.isInvalidType() && "no declarator info for valid type"); 4466 TInfo = Context.getTrivialTypeSourceInfo(T); 4467 } 4468 4469 // Scope manipulation handled by caller. 4470 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4471 D.getIdentifierLoc(), 4472 D.getIdentifier(), 4473 TInfo); 4474 4475 if (const TagType *TT = T->getAs<TagType>()) { 4476 TagDecl *TD = TT->getDecl(); 4477 4478 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4479 // keep track of the TypedefDecl. 4480 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4481 TD->setTypedefForAnonDecl(NewTD); 4482 } 4483 4484 if (D.isInvalidType()) 4485 NewTD->setInvalidDecl(); 4486 return NewTD; 4487} 4488 4489 4490/// \brief Determine whether a tag with a given kind is acceptable 4491/// as a redeclaration of the given tag declaration. 4492/// 4493/// \returns true if the new tag kind is acceptable, false otherwise. 4494bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4495 TagDecl::TagKind NewTag, 4496 SourceLocation NewTagLoc, 4497 const IdentifierInfo &Name) { 4498 // C++ [dcl.type.elab]p3: 4499 // The class-key or enum keyword present in the 4500 // elaborated-type-specifier shall agree in kind with the 4501 // declaration to which the name in theelaborated-type-specifier 4502 // refers. This rule also applies to the form of 4503 // elaborated-type-specifier that declares a class-name or 4504 // friend class since it can be construed as referring to the 4505 // definition of the class. Thus, in any 4506 // elaborated-type-specifier, the enum keyword shall be used to 4507 // refer to an enumeration (7.2), the union class-keyshall be 4508 // used to refer to a union (clause 9), and either the class or 4509 // struct class-key shall be used to refer to a class (clause 9) 4510 // declared using the class or struct class-key. 4511 TagDecl::TagKind OldTag = Previous->getTagKind(); 4512 if (OldTag == NewTag) 4513 return true; 4514 4515 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4516 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4517 // Warn about the struct/class tag mismatch. 4518 bool isTemplate = false; 4519 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4520 isTemplate = Record->getDescribedClassTemplate(); 4521 4522 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4523 << (NewTag == TagDecl::TK_class) 4524 << isTemplate << &Name 4525 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4526 OldTag == TagDecl::TK_class? "class" : "struct"); 4527 Diag(Previous->getLocation(), diag::note_previous_use); 4528 return true; 4529 } 4530 return false; 4531} 4532 4533/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4534/// former case, Name will be non-null. In the later case, Name will be null. 4535/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4536/// reference/declaration/definition of a tag. 4537Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4538 SourceLocation KWLoc, const CXXScopeSpec &SS, 4539 IdentifierInfo *Name, SourceLocation NameLoc, 4540 AttributeList *Attr, AccessSpecifier AS, 4541 MultiTemplateParamsArg TemplateParameterLists, 4542 bool &OwnedDecl, bool &IsDependent) { 4543 // If this is not a definition, it must have a name. 4544 assert((Name != 0 || TUK == TUK_Definition) && 4545 "Nameless record must be a definition!"); 4546 4547 OwnedDecl = false; 4548 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4549 4550 // FIXME: Check explicit specializations more carefully. 4551 bool isExplicitSpecialization = false; 4552 if (TUK != TUK_Reference) { 4553 if (TemplateParameterList *TemplateParams 4554 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4555 (TemplateParameterList**)TemplateParameterLists.get(), 4556 TemplateParameterLists.size(), 4557 isExplicitSpecialization)) { 4558 if (TemplateParams->size() > 0) { 4559 // This is a declaration or definition of a class template (which may 4560 // be a member of another template). 4561 OwnedDecl = false; 4562 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4563 SS, Name, NameLoc, Attr, 4564 TemplateParams, 4565 AS); 4566 TemplateParameterLists.release(); 4567 return Result.get(); 4568 } else { 4569 // The "template<>" header is extraneous. 4570 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4571 << ElaboratedType::getNameForTagKind(Kind) << Name; 4572 isExplicitSpecialization = true; 4573 } 4574 } 4575 4576 TemplateParameterLists.release(); 4577 } 4578 4579 DeclContext *SearchDC = CurContext; 4580 DeclContext *DC = CurContext; 4581 bool isStdBadAlloc = false; 4582 bool Invalid = false; 4583 4584 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4585 : NotForRedeclaration); 4586 4587 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4588 4589 if (Name && SS.isNotEmpty()) { 4590 // We have a nested-name tag ('struct foo::bar'). 4591 4592 // Check for invalid 'foo::'. 4593 if (SS.isInvalid()) { 4594 Name = 0; 4595 goto CreateNewDecl; 4596 } 4597 4598 // If this is a friend or a reference to a class in a dependent 4599 // context, don't try to make a decl for it. 4600 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4601 DC = computeDeclContext(SS, false); 4602 if (!DC) { 4603 IsDependent = true; 4604 return DeclPtrTy(); 4605 } 4606 } 4607 4608 if (RequireCompleteDeclContext(SS)) 4609 return DeclPtrTy::make((Decl *)0); 4610 4611 DC = computeDeclContext(SS, true); 4612 SearchDC = DC; 4613 // Look-up name inside 'foo::'. 4614 LookupQualifiedName(Previous, DC); 4615 4616 if (Previous.isAmbiguous()) 4617 return DeclPtrTy(); 4618 4619 // A tag 'foo::bar' must already exist. 4620 if (Previous.empty()) { 4621 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4622 Name = 0; 4623 Invalid = true; 4624 goto CreateNewDecl; 4625 } 4626 } else if (Name) { 4627 // If this is a named struct, check to see if there was a previous forward 4628 // declaration or definition. 4629 // FIXME: We're looking into outer scopes here, even when we 4630 // shouldn't be. Doing so can result in ambiguities that we 4631 // shouldn't be diagnosing. 4632 LookupName(Previous, S); 4633 4634 // Note: there used to be some attempt at recovery here. 4635 if (Previous.isAmbiguous()) 4636 return DeclPtrTy(); 4637 4638 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4639 // FIXME: This makes sure that we ignore the contexts associated 4640 // with C structs, unions, and enums when looking for a matching 4641 // tag declaration or definition. See the similar lookup tweak 4642 // in Sema::LookupName; is there a better way to deal with this? 4643 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4644 SearchDC = SearchDC->getParent(); 4645 } 4646 } 4647 4648 if (Previous.isSingleResult() && 4649 Previous.getFoundDecl()->isTemplateParameter()) { 4650 // Maybe we will complain about the shadowed template parameter. 4651 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4652 // Just pretend that we didn't see the previous declaration. 4653 Previous.clear(); 4654 } 4655 4656 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4657 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4658 // This is a declaration of or a reference to "std::bad_alloc". 4659 isStdBadAlloc = true; 4660 4661 if (Previous.empty() && StdBadAlloc) { 4662 // std::bad_alloc has been implicitly declared (but made invisible to 4663 // name lookup). Fill in this implicit declaration as the previous 4664 // declaration, so that the declarations get chained appropriately. 4665 Previous.addDecl(StdBadAlloc); 4666 } 4667 } 4668 4669 if (!Previous.empty()) { 4670 assert(Previous.isSingleResult()); 4671 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4672 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4673 // If this is a use of a previous tag, or if the tag is already declared 4674 // in the same scope (so that the definition/declaration completes or 4675 // rementions the tag), reuse the decl. 4676 if (TUK == TUK_Reference || TUK == TUK_Friend || 4677 isDeclInScope(PrevDecl, SearchDC, S)) { 4678 // Make sure that this wasn't declared as an enum and now used as a 4679 // struct or something similar. 4680 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4681 bool SafeToContinue 4682 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4683 Kind != TagDecl::TK_enum); 4684 if (SafeToContinue) 4685 Diag(KWLoc, diag::err_use_with_wrong_tag) 4686 << Name 4687 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4688 PrevTagDecl->getKindName()); 4689 else 4690 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4691 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4692 4693 if (SafeToContinue) 4694 Kind = PrevTagDecl->getTagKind(); 4695 else { 4696 // Recover by making this an anonymous redefinition. 4697 Name = 0; 4698 Previous.clear(); 4699 Invalid = true; 4700 } 4701 } 4702 4703 if (!Invalid) { 4704 // If this is a use, just return the declaration we found. 4705 4706 // FIXME: In the future, return a variant or some other clue 4707 // for the consumer of this Decl to know it doesn't own it. 4708 // For our current ASTs this shouldn't be a problem, but will 4709 // need to be changed with DeclGroups. 4710 if (TUK == TUK_Reference || TUK == TUK_Friend) 4711 return DeclPtrTy::make(PrevTagDecl); 4712 4713 // Diagnose attempts to redefine a tag. 4714 if (TUK == TUK_Definition) { 4715 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4716 // If we're defining a specialization and the previous definition 4717 // is from an implicit instantiation, don't emit an error 4718 // here; we'll catch this in the general case below. 4719 if (!isExplicitSpecialization || 4720 !isa<CXXRecordDecl>(Def) || 4721 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4722 == TSK_ExplicitSpecialization) { 4723 Diag(NameLoc, diag::err_redefinition) << Name; 4724 Diag(Def->getLocation(), diag::note_previous_definition); 4725 // If this is a redefinition, recover by making this 4726 // struct be anonymous, which will make any later 4727 // references get the previous definition. 4728 Name = 0; 4729 Previous.clear(); 4730 Invalid = true; 4731 } 4732 } else { 4733 // If the type is currently being defined, complain 4734 // about a nested redefinition. 4735 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4736 if (Tag->isBeingDefined()) { 4737 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4738 Diag(PrevTagDecl->getLocation(), 4739 diag::note_previous_definition); 4740 Name = 0; 4741 Previous.clear(); 4742 Invalid = true; 4743 } 4744 } 4745 4746 // Okay, this is definition of a previously declared or referenced 4747 // tag PrevDecl. We're going to create a new Decl for it. 4748 } 4749 } 4750 // If we get here we have (another) forward declaration or we 4751 // have a definition. Just create a new decl. 4752 4753 } else { 4754 // If we get here, this is a definition of a new tag type in a nested 4755 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4756 // new decl/type. We set PrevDecl to NULL so that the entities 4757 // have distinct types. 4758 Previous.clear(); 4759 } 4760 // If we get here, we're going to create a new Decl. If PrevDecl 4761 // is non-NULL, it's a definition of the tag declared by 4762 // PrevDecl. If it's NULL, we have a new definition. 4763 } else { 4764 // PrevDecl is a namespace, template, or anything else 4765 // that lives in the IDNS_Tag identifier namespace. 4766 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4767 // The tag name clashes with a namespace name, issue an error and 4768 // recover by making this tag be anonymous. 4769 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4770 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4771 Name = 0; 4772 Previous.clear(); 4773 Invalid = true; 4774 } else { 4775 // The existing declaration isn't relevant to us; we're in a 4776 // new scope, so clear out the previous declaration. 4777 Previous.clear(); 4778 } 4779 } 4780 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4781 // C++ [basic.scope.pdecl]p5: 4782 // -- for an elaborated-type-specifier of the form 4783 // 4784 // class-key identifier 4785 // 4786 // if the elaborated-type-specifier is used in the 4787 // decl-specifier-seq or parameter-declaration-clause of a 4788 // function defined in namespace scope, the identifier is 4789 // declared as a class-name in the namespace that contains 4790 // the declaration; otherwise, except as a friend 4791 // declaration, the identifier is declared in the smallest 4792 // non-class, non-function-prototype scope that contains the 4793 // declaration. 4794 // 4795 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4796 // C structs and unions. 4797 // 4798 // It is an error in C++ to declare (rather than define) an enum 4799 // type, including via an elaborated type specifier. We'll 4800 // diagnose that later; for now, declare the enum in the same 4801 // scope as we would have picked for any other tag type. 4802 // 4803 // GNU C also supports this behavior as part of its incomplete 4804 // enum types extension, while GNU C++ does not. 4805 // 4806 // Find the context where we'll be declaring the tag. 4807 // FIXME: We would like to maintain the current DeclContext as the 4808 // lexical context, 4809 while (SearchDC->isRecord()) 4810 SearchDC = SearchDC->getParent(); 4811 4812 // Find the scope where we'll be declaring the tag. 4813 while (S->isClassScope() || 4814 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4815 ((S->getFlags() & Scope::DeclScope) == 0) || 4816 (S->getEntity() && 4817 ((DeclContext *)S->getEntity())->isTransparentContext())) 4818 S = S->getParent(); 4819 4820 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4821 // C++ [namespace.memdef]p3: 4822 // If a friend declaration in a non-local class first declares a 4823 // class or function, the friend class or function is a member of 4824 // the innermost enclosing namespace. 4825 while (!SearchDC->isFileContext()) 4826 SearchDC = SearchDC->getParent(); 4827 4828 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4829 while (S->getEntity() != SearchDC) 4830 S = S->getParent(); 4831 } 4832 4833CreateNewDecl: 4834 4835 TagDecl *PrevDecl = 0; 4836 if (Previous.isSingleResult()) 4837 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4838 4839 // If there is an identifier, use the location of the identifier as the 4840 // location of the decl, otherwise use the location of the struct/union 4841 // keyword. 4842 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4843 4844 // Otherwise, create a new declaration. If there is a previous 4845 // declaration of the same entity, the two will be linked via 4846 // PrevDecl. 4847 TagDecl *New; 4848 4849 if (Kind == TagDecl::TK_enum) { 4850 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4851 // enum X { A, B, C } D; D should chain to X. 4852 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4853 cast_or_null<EnumDecl>(PrevDecl)); 4854 // If this is an undefined enum, warn. 4855 if (TUK != TUK_Definition && !Invalid) { 4856 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4857 : diag::ext_forward_ref_enum; 4858 Diag(Loc, DK); 4859 } 4860 } else { 4861 // struct/union/class 4862 4863 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4864 // struct X { int A; } D; D should chain to X. 4865 if (getLangOptions().CPlusPlus) { 4866 // FIXME: Look for a way to use RecordDecl for simple structs. 4867 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4868 cast_or_null<CXXRecordDecl>(PrevDecl)); 4869 4870 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4871 StdBadAlloc = cast<CXXRecordDecl>(New); 4872 } else 4873 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4874 cast_or_null<RecordDecl>(PrevDecl)); 4875 } 4876 4877 if (Kind != TagDecl::TK_enum) { 4878 // Handle #pragma pack: if the #pragma pack stack has non-default 4879 // alignment, make up a packed attribute for this decl. These 4880 // attributes are checked when the ASTContext lays out the 4881 // structure. 4882 // 4883 // It is important for implementing the correct semantics that this 4884 // happen here (in act on tag decl). The #pragma pack stack is 4885 // maintained as a result of parser callbacks which can occur at 4886 // many points during the parsing of a struct declaration (because 4887 // the #pragma tokens are effectively skipped over during the 4888 // parsing of the struct). 4889 if (unsigned Alignment = getPragmaPackAlignment()) 4890 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4891 } 4892 4893 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4894 // C++ [dcl.typedef]p3: 4895 // [...] Similarly, in a given scope, a class or enumeration 4896 // shall not be declared with the same name as a typedef-name 4897 // that is declared in that scope and refers to a type other 4898 // than the class or enumeration itself. 4899 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4900 ForRedeclaration); 4901 LookupName(Lookup, S); 4902 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4903 NamedDecl *PrevTypedefNamed = PrevTypedef; 4904 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4905 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4906 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4907 Diag(Loc, diag::err_tag_definition_of_typedef) 4908 << Context.getTypeDeclType(New) 4909 << PrevTypedef->getUnderlyingType(); 4910 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4911 Invalid = true; 4912 } 4913 } 4914 4915 // If this is a specialization of a member class (of a class template), 4916 // check the specialization. 4917 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4918 Invalid = true; 4919 4920 if (Invalid) 4921 New->setInvalidDecl(); 4922 4923 if (Attr) 4924 ProcessDeclAttributeList(S, New, Attr); 4925 4926 // If we're declaring or defining a tag in function prototype scope 4927 // in C, note that this type can only be used within the function. 4928 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4929 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4930 4931 // Set the lexical context. If the tag has a C++ scope specifier, the 4932 // lexical context will be different from the semantic context. 4933 New->setLexicalDeclContext(CurContext); 4934 4935 // Mark this as a friend decl if applicable. 4936 if (TUK == TUK_Friend) 4937 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4938 4939 // Set the access specifier. 4940 if (!Invalid && TUK != TUK_Friend) 4941 SetMemberAccessSpecifier(New, PrevDecl, AS); 4942 4943 if (TUK == TUK_Definition) 4944 New->startDefinition(); 4945 4946 // If this has an identifier, add it to the scope stack. 4947 if (TUK == TUK_Friend) { 4948 // We might be replacing an existing declaration in the lookup tables; 4949 // if so, borrow its access specifier. 4950 if (PrevDecl) 4951 New->setAccess(PrevDecl->getAccess()); 4952 4953 // Friend tag decls are visible in fairly strange ways. 4954 if (!CurContext->isDependentContext()) { 4955 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4956 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4957 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4958 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4959 } 4960 } else if (Name) { 4961 S = getNonFieldDeclScope(S); 4962 PushOnScopeChains(New, S); 4963 } else { 4964 CurContext->addDecl(New); 4965 } 4966 4967 // If this is the C FILE type, notify the AST context. 4968 if (IdentifierInfo *II = New->getIdentifier()) 4969 if (!New->isInvalidDecl() && 4970 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4971 II->isStr("FILE")) 4972 Context.setFILEDecl(New); 4973 4974 OwnedDecl = true; 4975 return DeclPtrTy::make(New); 4976} 4977 4978void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4979 AdjustDeclIfTemplate(TagD); 4980 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4981 4982 // Enter the tag context. 4983 PushDeclContext(S, Tag); 4984} 4985 4986void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 4987 SourceLocation LBraceLoc) { 4988 AdjustDeclIfTemplate(TagD); 4989 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 4990 4991 FieldCollector->StartClass(); 4992 4993 if (!Record->getIdentifier()) 4994 return; 4995 4996 // C++ [class]p2: 4997 // [...] The class-name is also inserted into the scope of the 4998 // class itself; this is known as the injected-class-name. For 4999 // purposes of access checking, the injected-class-name is treated 5000 // as if it were a public member name. 5001 CXXRecordDecl *InjectedClassName 5002 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5003 CurContext, Record->getLocation(), 5004 Record->getIdentifier(), 5005 Record->getTagKeywordLoc(), 5006 Record); 5007 InjectedClassName->setImplicit(); 5008 InjectedClassName->setAccess(AS_public); 5009 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5010 InjectedClassName->setDescribedClassTemplate(Template); 5011 PushOnScopeChains(InjectedClassName, S); 5012 assert(InjectedClassName->isInjectedClassName() && 5013 "Broken injected-class-name"); 5014} 5015 5016void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5017 SourceLocation RBraceLoc) { 5018 AdjustDeclIfTemplate(TagD); 5019 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5020 Tag->setRBraceLoc(RBraceLoc); 5021 5022 if (isa<CXXRecordDecl>(Tag)) 5023 FieldCollector->FinishClass(); 5024 5025 // Exit this scope of this tag's definition. 5026 PopDeclContext(); 5027 5028 // Notify the consumer that we've defined a tag. 5029 Consumer.HandleTagDeclDefinition(Tag); 5030} 5031 5032// Note that FieldName may be null for anonymous bitfields. 5033bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5034 QualType FieldTy, const Expr *BitWidth, 5035 bool *ZeroWidth) { 5036 // Default to true; that shouldn't confuse checks for emptiness 5037 if (ZeroWidth) 5038 *ZeroWidth = true; 5039 5040 // C99 6.7.2.1p4 - verify the field type. 5041 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5042 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5043 // Handle incomplete types with specific error. 5044 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5045 return true; 5046 if (FieldName) 5047 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5048 << FieldName << FieldTy << BitWidth->getSourceRange(); 5049 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5050 << FieldTy << BitWidth->getSourceRange(); 5051 } 5052 5053 // If the bit-width is type- or value-dependent, don't try to check 5054 // it now. 5055 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5056 return false; 5057 5058 llvm::APSInt Value; 5059 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5060 return true; 5061 5062 if (Value != 0 && ZeroWidth) 5063 *ZeroWidth = false; 5064 5065 // Zero-width bitfield is ok for anonymous field. 5066 if (Value == 0 && FieldName) 5067 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5068 5069 if (Value.isSigned() && Value.isNegative()) { 5070 if (FieldName) 5071 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5072 << FieldName << Value.toString(10); 5073 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5074 << Value.toString(10); 5075 } 5076 5077 if (!FieldTy->isDependentType()) { 5078 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5079 if (Value.getZExtValue() > TypeSize) { 5080 if (FieldName) 5081 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5082 << FieldName << (unsigned)TypeSize; 5083 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5084 << (unsigned)TypeSize; 5085 } 5086 } 5087 5088 return false; 5089} 5090 5091/// ActOnField - Each field of a struct/union/class is passed into this in order 5092/// to create a FieldDecl object for it. 5093Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5094 SourceLocation DeclStart, 5095 Declarator &D, ExprTy *BitfieldWidth) { 5096 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5097 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5098 AS_public); 5099 return DeclPtrTy::make(Res); 5100} 5101 5102/// HandleField - Analyze a field of a C struct or a C++ data member. 5103/// 5104FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5105 SourceLocation DeclStart, 5106 Declarator &D, Expr *BitWidth, 5107 AccessSpecifier AS) { 5108 IdentifierInfo *II = D.getIdentifier(); 5109 SourceLocation Loc = DeclStart; 5110 if (II) Loc = D.getIdentifierLoc(); 5111 5112 TypeSourceInfo *TInfo = 0; 5113 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5114 if (getLangOptions().CPlusPlus) 5115 CheckExtraCXXDefaultArguments(D); 5116 5117 DiagnoseFunctionSpecifiers(D); 5118 5119 if (D.getDeclSpec().isThreadSpecified()) 5120 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5121 5122 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5123 ForRedeclaration); 5124 5125 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5126 // Maybe we will complain about the shadowed template parameter. 5127 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5128 // Just pretend that we didn't see the previous declaration. 5129 PrevDecl = 0; 5130 } 5131 5132 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5133 PrevDecl = 0; 5134 5135 bool Mutable 5136 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5137 SourceLocation TSSL = D.getSourceRange().getBegin(); 5138 FieldDecl *NewFD 5139 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5140 AS, PrevDecl, &D); 5141 if (NewFD->isInvalidDecl() && PrevDecl) { 5142 // Don't introduce NewFD into scope; there's already something 5143 // with the same name in the same scope. 5144 } else if (II) { 5145 PushOnScopeChains(NewFD, S); 5146 } else 5147 Record->addDecl(NewFD); 5148 5149 return NewFD; 5150} 5151 5152/// \brief Build a new FieldDecl and check its well-formedness. 5153/// 5154/// This routine builds a new FieldDecl given the fields name, type, 5155/// record, etc. \p PrevDecl should refer to any previous declaration 5156/// with the same name and in the same scope as the field to be 5157/// created. 5158/// 5159/// \returns a new FieldDecl. 5160/// 5161/// \todo The Declarator argument is a hack. It will be removed once 5162FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5163 TypeSourceInfo *TInfo, 5164 RecordDecl *Record, SourceLocation Loc, 5165 bool Mutable, Expr *BitWidth, 5166 SourceLocation TSSL, 5167 AccessSpecifier AS, NamedDecl *PrevDecl, 5168 Declarator *D) { 5169 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5170 bool InvalidDecl = false; 5171 if (D) InvalidDecl = D->isInvalidType(); 5172 5173 // If we receive a broken type, recover by assuming 'int' and 5174 // marking this declaration as invalid. 5175 if (T.isNull()) { 5176 InvalidDecl = true; 5177 T = Context.IntTy; 5178 } 5179 5180 QualType EltTy = Context.getBaseElementType(T); 5181 if (!EltTy->isDependentType() && 5182 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5183 InvalidDecl = true; 5184 5185 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5186 // than a variably modified type. 5187 if (!InvalidDecl && T->isVariablyModifiedType()) { 5188 bool SizeIsNegative; 5189 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5190 SizeIsNegative); 5191 if (!FixedTy.isNull()) { 5192 Diag(Loc, diag::warn_illegal_constant_array_size); 5193 T = FixedTy; 5194 } else { 5195 if (SizeIsNegative) 5196 Diag(Loc, diag::err_typecheck_negative_array_size); 5197 else 5198 Diag(Loc, diag::err_typecheck_field_variable_size); 5199 InvalidDecl = true; 5200 } 5201 } 5202 5203 // Fields can not have abstract class types 5204 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5205 diag::err_abstract_type_in_decl, 5206 AbstractFieldType)) 5207 InvalidDecl = true; 5208 5209 bool ZeroWidth = false; 5210 // If this is declared as a bit-field, check the bit-field. 5211 if (!InvalidDecl && BitWidth && 5212 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5213 InvalidDecl = true; 5214 DeleteExpr(BitWidth); 5215 BitWidth = 0; 5216 ZeroWidth = false; 5217 } 5218 5219 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5220 BitWidth, Mutable); 5221 if (InvalidDecl) 5222 NewFD->setInvalidDecl(); 5223 5224 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5225 Diag(Loc, diag::err_duplicate_member) << II; 5226 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5227 NewFD->setInvalidDecl(); 5228 } 5229 5230 if (getLangOptions().CPlusPlus) { 5231 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5232 5233 if (!T->isPODType()) 5234 CXXRecord->setPOD(false); 5235 if (!ZeroWidth) 5236 CXXRecord->setEmpty(false); 5237 5238 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5239 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5240 5241 if (!RDecl->hasTrivialConstructor()) 5242 CXXRecord->setHasTrivialConstructor(false); 5243 if (!RDecl->hasTrivialCopyConstructor()) 5244 CXXRecord->setHasTrivialCopyConstructor(false); 5245 if (!RDecl->hasTrivialCopyAssignment()) 5246 CXXRecord->setHasTrivialCopyAssignment(false); 5247 if (!RDecl->hasTrivialDestructor()) 5248 CXXRecord->setHasTrivialDestructor(false); 5249 5250 // C++ 9.5p1: An object of a class with a non-trivial 5251 // constructor, a non-trivial copy constructor, a non-trivial 5252 // destructor, or a non-trivial copy assignment operator 5253 // cannot be a member of a union, nor can an array of such 5254 // objects. 5255 // TODO: C++0x alters this restriction significantly. 5256 if (Record->isUnion()) { 5257 // We check for copy constructors before constructors 5258 // because otherwise we'll never get complaints about 5259 // copy constructors. 5260 5261 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5262 5263 CXXSpecialMember member; 5264 if (!RDecl->hasTrivialCopyConstructor()) 5265 member = CXXCopyConstructor; 5266 else if (!RDecl->hasTrivialConstructor()) 5267 member = CXXDefaultConstructor; 5268 else if (!RDecl->hasTrivialCopyAssignment()) 5269 member = CXXCopyAssignment; 5270 else if (!RDecl->hasTrivialDestructor()) 5271 member = CXXDestructor; 5272 else 5273 member = invalid; 5274 5275 if (member != invalid) { 5276 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5277 DiagnoseNontrivial(RT, member); 5278 NewFD->setInvalidDecl(); 5279 } 5280 } 5281 } 5282 } 5283 5284 // FIXME: We need to pass in the attributes given an AST 5285 // representation, not a parser representation. 5286 if (D) 5287 // FIXME: What to pass instead of TUScope? 5288 ProcessDeclAttributes(TUScope, NewFD, *D); 5289 5290 if (T.isObjCGCWeak()) 5291 Diag(Loc, diag::warn_attribute_weak_on_field); 5292 5293 NewFD->setAccess(AS); 5294 5295 // C++ [dcl.init.aggr]p1: 5296 // An aggregate is an array or a class (clause 9) with [...] no 5297 // private or protected non-static data members (clause 11). 5298 // A POD must be an aggregate. 5299 if (getLangOptions().CPlusPlus && 5300 (AS == AS_private || AS == AS_protected)) { 5301 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5302 CXXRecord->setAggregate(false); 5303 CXXRecord->setPOD(false); 5304 } 5305 5306 return NewFD; 5307} 5308 5309/// DiagnoseNontrivial - Given that a class has a non-trivial 5310/// special member, figure out why. 5311void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5312 QualType QT(T, 0U); 5313 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5314 5315 // Check whether the member was user-declared. 5316 switch (member) { 5317 case CXXDefaultConstructor: 5318 if (RD->hasUserDeclaredConstructor()) { 5319 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5320 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5321 const FunctionDecl *body = 0; 5322 ci->getBody(body); 5323 if (!body || 5324 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5325 SourceLocation CtorLoc = ci->getLocation(); 5326 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5327 return; 5328 } 5329 } 5330 5331 assert(0 && "found no user-declared constructors"); 5332 return; 5333 } 5334 break; 5335 5336 case CXXCopyConstructor: 5337 if (RD->hasUserDeclaredCopyConstructor()) { 5338 SourceLocation CtorLoc = 5339 RD->getCopyConstructor(Context, 0)->getLocation(); 5340 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5341 return; 5342 } 5343 break; 5344 5345 case CXXCopyAssignment: 5346 if (RD->hasUserDeclaredCopyAssignment()) { 5347 // FIXME: this should use the location of the copy 5348 // assignment, not the type. 5349 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5350 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5351 return; 5352 } 5353 break; 5354 5355 case CXXDestructor: 5356 if (RD->hasUserDeclaredDestructor()) { 5357 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5358 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5359 return; 5360 } 5361 break; 5362 } 5363 5364 typedef CXXRecordDecl::base_class_iterator base_iter; 5365 5366 // Virtual bases and members inhibit trivial copying/construction, 5367 // but not trivial destruction. 5368 if (member != CXXDestructor) { 5369 // Check for virtual bases. vbases includes indirect virtual bases, 5370 // so we just iterate through the direct bases. 5371 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5372 if (bi->isVirtual()) { 5373 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5374 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5375 return; 5376 } 5377 5378 // Check for virtual methods. 5379 typedef CXXRecordDecl::method_iterator meth_iter; 5380 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5381 ++mi) { 5382 if (mi->isVirtual()) { 5383 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5384 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5385 return; 5386 } 5387 } 5388 } 5389 5390 bool (CXXRecordDecl::*hasTrivial)() const; 5391 switch (member) { 5392 case CXXDefaultConstructor: 5393 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5394 case CXXCopyConstructor: 5395 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5396 case CXXCopyAssignment: 5397 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5398 case CXXDestructor: 5399 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5400 default: 5401 assert(0 && "unexpected special member"); return; 5402 } 5403 5404 // Check for nontrivial bases (and recurse). 5405 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5406 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5407 assert(BaseRT && "Don't know how to handle dependent bases"); 5408 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5409 if (!(BaseRecTy->*hasTrivial)()) { 5410 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5411 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5412 DiagnoseNontrivial(BaseRT, member); 5413 return; 5414 } 5415 } 5416 5417 // Check for nontrivial members (and recurse). 5418 typedef RecordDecl::field_iterator field_iter; 5419 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5420 ++fi) { 5421 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5422 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5423 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5424 5425 if (!(EltRD->*hasTrivial)()) { 5426 SourceLocation FLoc = (*fi)->getLocation(); 5427 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5428 DiagnoseNontrivial(EltRT, member); 5429 return; 5430 } 5431 } 5432 } 5433 5434 assert(0 && "found no explanation for non-trivial member"); 5435} 5436 5437/// TranslateIvarVisibility - Translate visibility from a token ID to an 5438/// AST enum value. 5439static ObjCIvarDecl::AccessControl 5440TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5441 switch (ivarVisibility) { 5442 default: assert(0 && "Unknown visitibility kind"); 5443 case tok::objc_private: return ObjCIvarDecl::Private; 5444 case tok::objc_public: return ObjCIvarDecl::Public; 5445 case tok::objc_protected: return ObjCIvarDecl::Protected; 5446 case tok::objc_package: return ObjCIvarDecl::Package; 5447 } 5448} 5449 5450/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5451/// in order to create an IvarDecl object for it. 5452Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5453 SourceLocation DeclStart, 5454 DeclPtrTy IntfDecl, 5455 Declarator &D, ExprTy *BitfieldWidth, 5456 tok::ObjCKeywordKind Visibility) { 5457 5458 IdentifierInfo *II = D.getIdentifier(); 5459 Expr *BitWidth = (Expr*)BitfieldWidth; 5460 SourceLocation Loc = DeclStart; 5461 if (II) Loc = D.getIdentifierLoc(); 5462 5463 // FIXME: Unnamed fields can be handled in various different ways, for 5464 // example, unnamed unions inject all members into the struct namespace! 5465 5466 TypeSourceInfo *TInfo = 0; 5467 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5468 5469 if (BitWidth) { 5470 // 6.7.2.1p3, 6.7.2.1p4 5471 if (VerifyBitField(Loc, II, T, BitWidth)) { 5472 D.setInvalidType(); 5473 DeleteExpr(BitWidth); 5474 BitWidth = 0; 5475 } 5476 } else { 5477 // Not a bitfield. 5478 5479 // validate II. 5480 5481 } 5482 5483 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5484 // than a variably modified type. 5485 if (T->isVariablyModifiedType()) { 5486 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5487 D.setInvalidType(); 5488 } 5489 5490 // Get the visibility (access control) for this ivar. 5491 ObjCIvarDecl::AccessControl ac = 5492 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5493 : ObjCIvarDecl::None; 5494 // Must set ivar's DeclContext to its enclosing interface. 5495 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5496 DeclContext *EnclosingContext; 5497 if (ObjCImplementationDecl *IMPDecl = 5498 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5499 // Case of ivar declared in an implementation. Context is that of its class. 5500 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5501 assert(IDecl && "No class- ActOnIvar"); 5502 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5503 } else 5504 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5505 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5506 5507 // Construct the decl. 5508 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5509 EnclosingContext, Loc, II, T, 5510 TInfo, ac, (Expr *)BitfieldWidth); 5511 5512 if (II) { 5513 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5514 ForRedeclaration); 5515 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5516 && !isa<TagDecl>(PrevDecl)) { 5517 Diag(Loc, diag::err_duplicate_member) << II; 5518 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5519 NewID->setInvalidDecl(); 5520 } 5521 } 5522 5523 // Process attributes attached to the ivar. 5524 ProcessDeclAttributes(S, NewID, D); 5525 5526 if (D.isInvalidType()) 5527 NewID->setInvalidDecl(); 5528 5529 if (II) { 5530 // FIXME: When interfaces are DeclContexts, we'll need to add 5531 // these to the interface. 5532 S->AddDecl(DeclPtrTy::make(NewID)); 5533 IdResolver.AddDecl(NewID); 5534 } 5535 5536 return DeclPtrTy::make(NewID); 5537} 5538 5539void Sema::ActOnFields(Scope* S, 5540 SourceLocation RecLoc, DeclPtrTy RecDecl, 5541 DeclPtrTy *Fields, unsigned NumFields, 5542 SourceLocation LBrac, SourceLocation RBrac, 5543 AttributeList *Attr) { 5544 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5545 assert(EnclosingDecl && "missing record or interface decl"); 5546 5547 // If the decl this is being inserted into is invalid, then it may be a 5548 // redeclaration or some other bogus case. Don't try to add fields to it. 5549 if (EnclosingDecl->isInvalidDecl()) { 5550 // FIXME: Deallocate fields? 5551 return; 5552 } 5553 5554 5555 // Verify that all the fields are okay. 5556 unsigned NumNamedMembers = 0; 5557 llvm::SmallVector<FieldDecl*, 32> RecFields; 5558 5559 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5560 for (unsigned i = 0; i != NumFields; ++i) { 5561 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5562 5563 // Get the type for the field. 5564 Type *FDTy = FD->getType().getTypePtr(); 5565 5566 if (!FD->isAnonymousStructOrUnion()) { 5567 // Remember all fields written by the user. 5568 RecFields.push_back(FD); 5569 } 5570 5571 // If the field is already invalid for some reason, don't emit more 5572 // diagnostics about it. 5573 if (FD->isInvalidDecl()) { 5574 EnclosingDecl->setInvalidDecl(); 5575 continue; 5576 } 5577 5578 // C99 6.7.2.1p2: 5579 // A structure or union shall not contain a member with 5580 // incomplete or function type (hence, a structure shall not 5581 // contain an instance of itself, but may contain a pointer to 5582 // an instance of itself), except that the last member of a 5583 // structure with more than one named member may have incomplete 5584 // array type; such a structure (and any union containing, 5585 // possibly recursively, a member that is such a structure) 5586 // shall not be a member of a structure or an element of an 5587 // array. 5588 if (FDTy->isFunctionType()) { 5589 // Field declared as a function. 5590 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5591 << FD->getDeclName(); 5592 FD->setInvalidDecl(); 5593 EnclosingDecl->setInvalidDecl(); 5594 continue; 5595 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5596 Record && Record->isStruct()) { 5597 // Flexible array member. 5598 if (NumNamedMembers < 1) { 5599 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5600 << FD->getDeclName(); 5601 FD->setInvalidDecl(); 5602 EnclosingDecl->setInvalidDecl(); 5603 continue; 5604 } 5605 // Okay, we have a legal flexible array member at the end of the struct. 5606 if (Record) 5607 Record->setHasFlexibleArrayMember(true); 5608 } else if (!FDTy->isDependentType() && 5609 RequireCompleteType(FD->getLocation(), FD->getType(), 5610 diag::err_field_incomplete)) { 5611 // Incomplete type 5612 FD->setInvalidDecl(); 5613 EnclosingDecl->setInvalidDecl(); 5614 continue; 5615 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5616 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5617 // If this is a member of a union, then entire union becomes "flexible". 5618 if (Record && Record->isUnion()) { 5619 Record->setHasFlexibleArrayMember(true); 5620 } else { 5621 // If this is a struct/class and this is not the last element, reject 5622 // it. Note that GCC supports variable sized arrays in the middle of 5623 // structures. 5624 if (i != NumFields-1) 5625 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5626 << FD->getDeclName() << FD->getType(); 5627 else { 5628 // We support flexible arrays at the end of structs in 5629 // other structs as an extension. 5630 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5631 << FD->getDeclName(); 5632 if (Record) 5633 Record->setHasFlexibleArrayMember(true); 5634 } 5635 } 5636 } 5637 if (Record && FDTTy->getDecl()->hasObjectMember()) 5638 Record->setHasObjectMember(true); 5639 } else if (FDTy->isObjCInterfaceType()) { 5640 /// A field cannot be an Objective-c object 5641 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5642 FD->setInvalidDecl(); 5643 EnclosingDecl->setInvalidDecl(); 5644 continue; 5645 } else if (getLangOptions().ObjC1 && 5646 getLangOptions().getGCMode() != LangOptions::NonGC && 5647 Record && 5648 (FD->getType()->isObjCObjectPointerType() || 5649 FD->getType().isObjCGCStrong())) 5650 Record->setHasObjectMember(true); 5651 // Keep track of the number of named members. 5652 if (FD->getIdentifier()) 5653 ++NumNamedMembers; 5654 } 5655 5656 // Okay, we successfully defined 'Record'. 5657 if (Record) { 5658 Record->completeDefinition(Context); 5659 } else { 5660 ObjCIvarDecl **ClsFields = 5661 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5662 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5663 ID->setIVarList(ClsFields, RecFields.size(), Context); 5664 ID->setLocEnd(RBrac); 5665 // Add ivar's to class's DeclContext. 5666 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5667 ClsFields[i]->setLexicalDeclContext(ID); 5668 ID->addDecl(ClsFields[i]); 5669 } 5670 // Must enforce the rule that ivars in the base classes may not be 5671 // duplicates. 5672 if (ID->getSuperClass()) { 5673 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5674 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5675 ObjCIvarDecl* Ivar = (*IVI); 5676 5677 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5678 ObjCIvarDecl* prevIvar = 5679 ID->getSuperClass()->lookupInstanceVariable(II); 5680 if (prevIvar) { 5681 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5682 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5683 } 5684 } 5685 } 5686 } 5687 } else if (ObjCImplementationDecl *IMPDecl = 5688 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5689 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5690 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5691 // Ivar declared in @implementation never belongs to the implementation. 5692 // Only it is in implementation's lexical context. 5693 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5694 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5695 } 5696 } 5697 5698 if (Attr) 5699 ProcessDeclAttributeList(S, Record, Attr); 5700} 5701 5702EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5703 EnumConstantDecl *LastEnumConst, 5704 SourceLocation IdLoc, 5705 IdentifierInfo *Id, 5706 ExprArg val) { 5707 Expr *Val = (Expr *)val.get(); 5708 5709 llvm::APSInt EnumVal(32); 5710 QualType EltTy; 5711 if (Val) { 5712 if (Enum->isDependentType()) 5713 EltTy = Context.DependentTy; 5714 else { 5715 // Make sure to promote the operand type to int. 5716 UsualUnaryConversions(Val); 5717 if (Val != val.get()) { 5718 val.release(); 5719 val = Val; 5720 } 5721 5722 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5723 SourceLocation ExpLoc; 5724 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 5725 Val = 0; 5726 } else { 5727 EltTy = Val->getType(); 5728 } 5729 } 5730 } 5731 5732 if (!Val) { 5733 if (Enum->isDependentType()) 5734 EltTy = Context.DependentTy; 5735 else if (LastEnumConst) { 5736 // Assign the last value + 1. 5737 EnumVal = LastEnumConst->getInitVal(); 5738 ++EnumVal; 5739 5740 // Check for overflow on increment. 5741 if (EnumVal < LastEnumConst->getInitVal()) 5742 Diag(IdLoc, diag::warn_enum_value_overflow); 5743 5744 EltTy = LastEnumConst->getType(); 5745 } else { 5746 // First value, set to zero. 5747 EltTy = Context.IntTy; 5748 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5749 EnumVal.setIsSigned(true); 5750 } 5751 } 5752 5753 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5754 5755 val.release(); 5756 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5757 Val, EnumVal); 5758} 5759 5760 5761Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5762 DeclPtrTy lastEnumConst, 5763 SourceLocation IdLoc, 5764 IdentifierInfo *Id, 5765 SourceLocation EqualLoc, ExprTy *val) { 5766 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5767 EnumConstantDecl *LastEnumConst = 5768 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5769 Expr *Val = static_cast<Expr*>(val); 5770 5771 // The scope passed in may not be a decl scope. Zip up the scope tree until 5772 // we find one that is. 5773 S = getNonFieldDeclScope(S); 5774 5775 // Verify that there isn't already something declared with this name in this 5776 // scope. 5777 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5778 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5779 // Maybe we will complain about the shadowed template parameter. 5780 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5781 // Just pretend that we didn't see the previous declaration. 5782 PrevDecl = 0; 5783 } 5784 5785 if (PrevDecl) { 5786 // When in C++, we may get a TagDecl with the same name; in this case the 5787 // enum constant will 'hide' the tag. 5788 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5789 "Received TagDecl when not in C++!"); 5790 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5791 if (isa<EnumConstantDecl>(PrevDecl)) 5792 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5793 else 5794 Diag(IdLoc, diag::err_redefinition) << Id; 5795 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5796 if (Val) Val->Destroy(Context); 5797 return DeclPtrTy(); 5798 } 5799 } 5800 5801 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5802 IdLoc, Id, Owned(Val)); 5803 5804 // Register this decl in the current scope stack. 5805 if (New) 5806 PushOnScopeChains(New, S); 5807 5808 return DeclPtrTy::make(New); 5809} 5810 5811void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5812 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5813 DeclPtrTy *Elements, unsigned NumElements, 5814 Scope *S, AttributeList *Attr) { 5815 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5816 QualType EnumType = Context.getTypeDeclType(Enum); 5817 5818 if (Attr) 5819 ProcessDeclAttributeList(S, Enum, Attr); 5820 5821 if (Enum->isDependentType()) { 5822 for (unsigned i = 0; i != NumElements; ++i) { 5823 EnumConstantDecl *ECD = 5824 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5825 if (!ECD) continue; 5826 5827 ECD->setType(EnumType); 5828 } 5829 5830 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 5831 return; 5832 } 5833 5834 // TODO: If the result value doesn't fit in an int, it must be a long or long 5835 // long value. ISO C does not support this, but GCC does as an extension, 5836 // emit a warning. 5837 unsigned IntWidth = Context.Target.getIntWidth(); 5838 unsigned CharWidth = Context.Target.getCharWidth(); 5839 unsigned ShortWidth = Context.Target.getShortWidth(); 5840 5841 // Verify that all the values are okay, compute the size of the values, and 5842 // reverse the list. 5843 unsigned NumNegativeBits = 0; 5844 unsigned NumPositiveBits = 0; 5845 5846 // Keep track of whether all elements have type int. 5847 bool AllElementsInt = true; 5848 5849 for (unsigned i = 0; i != NumElements; ++i) { 5850 EnumConstantDecl *ECD = 5851 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5852 if (!ECD) continue; // Already issued a diagnostic. 5853 5854 // If the enum value doesn't fit in an int, emit an extension warning. 5855 const llvm::APSInt &InitVal = ECD->getInitVal(); 5856 assert(InitVal.getBitWidth() >= IntWidth && 5857 "Should have promoted value to int"); 5858 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 5859 llvm::APSInt V(InitVal); 5860 V.trunc(IntWidth); 5861 V.extend(InitVal.getBitWidth()); 5862 if (V != InitVal) 5863 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5864 << InitVal.toString(10); 5865 } 5866 5867 // Keep track of the size of positive and negative values. 5868 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5869 NumPositiveBits = std::max(NumPositiveBits, 5870 (unsigned)InitVal.getActiveBits()); 5871 else 5872 NumNegativeBits = std::max(NumNegativeBits, 5873 (unsigned)InitVal.getMinSignedBits()); 5874 5875 // Keep track of whether every enum element has type int (very commmon). 5876 if (AllElementsInt) 5877 AllElementsInt = ECD->getType() == Context.IntTy; 5878 } 5879 5880 // Figure out the type that should be used for this enum. 5881 // FIXME: Support -fshort-enums. 5882 QualType BestType; 5883 unsigned BestWidth; 5884 5885 // C++0x N3000 [conv.prom]p3: 5886 // An rvalue of an unscoped enumeration type whose underlying 5887 // type is not fixed can be converted to an rvalue of the first 5888 // of the following types that can represent all the values of 5889 // the enumeration: int, unsigned int, long int, unsigned long 5890 // int, long long int, or unsigned long long int. 5891 // C99 6.4.4.3p2: 5892 // An identifier declared as an enumeration constant has type int. 5893 // The C99 rule is modified by a gcc extension 5894 QualType BestPromotionType; 5895 5896 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5897 5898 if (NumNegativeBits) { 5899 // If there is a negative value, figure out the smallest integer type (of 5900 // int/long/longlong) that fits. 5901 // If it's packed, check also if it fits a char or a short. 5902 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5903 BestType = Context.SignedCharTy; 5904 BestWidth = CharWidth; 5905 } else if (Packed && NumNegativeBits <= ShortWidth && 5906 NumPositiveBits < ShortWidth) { 5907 BestType = Context.ShortTy; 5908 BestWidth = ShortWidth; 5909 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5910 BestType = Context.IntTy; 5911 BestWidth = IntWidth; 5912 } else { 5913 BestWidth = Context.Target.getLongWidth(); 5914 5915 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5916 BestType = Context.LongTy; 5917 } else { 5918 BestWidth = Context.Target.getLongLongWidth(); 5919 5920 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5921 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5922 BestType = Context.LongLongTy; 5923 } 5924 } 5925 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5926 } else { 5927 // If there is no negative value, figure out which of uint, ulong, ulonglong 5928 // fits. 5929 // If it's packed, check also if it fits a char or a short. 5930 if (Packed && NumPositiveBits <= CharWidth) { 5931 BestType = Context.UnsignedCharTy; 5932 BestPromotionType = Context.IntTy; 5933 BestWidth = CharWidth; 5934 } else if (Packed && NumPositiveBits <= ShortWidth) { 5935 BestType = Context.UnsignedShortTy; 5936 BestPromotionType = Context.IntTy; 5937 BestWidth = ShortWidth; 5938 } else if (NumPositiveBits <= IntWidth) { 5939 BestType = Context.UnsignedIntTy; 5940 BestWidth = IntWidth; 5941 BestPromotionType = (NumPositiveBits == BestWidth 5942 ? Context.UnsignedIntTy : Context.IntTy); 5943 } else if (NumPositiveBits <= 5944 (BestWidth = Context.Target.getLongWidth())) { 5945 BestType = Context.UnsignedLongTy; 5946 BestPromotionType = (NumPositiveBits == BestWidth 5947 ? Context.UnsignedLongTy : Context.LongTy); 5948 } else { 5949 BestWidth = Context.Target.getLongLongWidth(); 5950 assert(NumPositiveBits <= BestWidth && 5951 "How could an initializer get larger than ULL?"); 5952 BestType = Context.UnsignedLongLongTy; 5953 BestPromotionType = (NumPositiveBits == BestWidth 5954 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5955 } 5956 } 5957 5958 // If we're in C and the promotion type is larger than an int, just 5959 // use the underlying type, which is generally the unsigned integer 5960 // type of the same rank as the promotion type. This is how the gcc 5961 // extension works. 5962 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5963 BestPromotionType = BestType; 5964 5965 // Loop over all of the enumerator constants, changing their types to match 5966 // the type of the enum if needed. 5967 for (unsigned i = 0; i != NumElements; ++i) { 5968 EnumConstantDecl *ECD = 5969 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5970 if (!ECD) continue; // Already issued a diagnostic. 5971 5972 // Standard C says the enumerators have int type, but we allow, as an 5973 // extension, the enumerators to be larger than int size. If each 5974 // enumerator value fits in an int, type it as an int, otherwise type it the 5975 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5976 // that X has type 'int', not 'unsigned'. 5977 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 5978 continue; 5979 5980 // Determine whether the value fits into an int. 5981 llvm::APSInt InitVal = ECD->getInitVal(); 5982 bool FitsInInt; 5983 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5984 FitsInInt = InitVal.getActiveBits() < IntWidth; 5985 else 5986 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5987 5988 // If it fits into an integer type, force it. Otherwise force it to match 5989 // the enum decl type. 5990 QualType NewTy; 5991 unsigned NewWidth; 5992 bool NewSign; 5993 if (FitsInInt && !getLangOptions().CPlusPlus) { 5994 NewTy = Context.IntTy; 5995 NewWidth = IntWidth; 5996 NewSign = true; 5997 } else if (ECD->getType() == BestType) { 5998 // Already the right type! 5999 if (getLangOptions().CPlusPlus) 6000 // C++ [dcl.enum]p4: Following the closing brace of an 6001 // enum-specifier, each enumerator has the type of its 6002 // enumeration. 6003 ECD->setType(EnumType); 6004 continue; 6005 } else { 6006 NewTy = BestType; 6007 NewWidth = BestWidth; 6008 NewSign = BestType->isSignedIntegerType(); 6009 } 6010 6011 // Adjust the APSInt value. 6012 InitVal.extOrTrunc(NewWidth); 6013 InitVal.setIsSigned(NewSign); 6014 ECD->setInitVal(InitVal); 6015 6016 // Adjust the Expr initializer and type. 6017 if (ECD->getInitExpr()) 6018 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6019 CastExpr::CK_IntegralCast, 6020 ECD->getInitExpr(), 6021 /*isLvalue=*/false)); 6022 if (getLangOptions().CPlusPlus) 6023 // C++ [dcl.enum]p4: Following the closing brace of an 6024 // enum-specifier, each enumerator has the type of its 6025 // enumeration. 6026 ECD->setType(EnumType); 6027 else 6028 ECD->setType(NewTy); 6029 } 6030 6031 Enum->completeDefinition(Context, BestType, BestPromotionType); 6032} 6033 6034Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6035 ExprArg expr) { 6036 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6037 6038 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6039 Loc, AsmString); 6040 CurContext->addDecl(New); 6041 return DeclPtrTy::make(New); 6042} 6043 6044void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6045 SourceLocation PragmaLoc, 6046 SourceLocation NameLoc) { 6047 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6048 6049 if (PrevDecl) { 6050 PrevDecl->addAttr(::new (Context) WeakAttr()); 6051 } else { 6052 (void)WeakUndeclaredIdentifiers.insert( 6053 std::pair<IdentifierInfo*,WeakInfo> 6054 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6055 } 6056} 6057 6058void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6059 IdentifierInfo* AliasName, 6060 SourceLocation PragmaLoc, 6061 SourceLocation NameLoc, 6062 SourceLocation AliasNameLoc) { 6063 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6064 WeakInfo W = WeakInfo(Name, NameLoc); 6065 6066 if (PrevDecl) { 6067 if (!PrevDecl->hasAttr<AliasAttr>()) 6068 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6069 DeclApplyPragmaWeak(TUScope, ND, W); 6070 } else { 6071 (void)WeakUndeclaredIdentifiers.insert( 6072 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6073 } 6074} 6075