SemaDecl.cpp revision 7a1dc562d4ad59237ed9fe7e8cef56f9eaa7a26c
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 <algorithm> 39#include <cstring> 40#include <functional> 41#include <queue> 42using namespace clang; 43 44/// getDeclName - Return a pretty name for the specified decl if possible, or 45/// an empty string if not. This is used for pretty crash reporting. 46std::string Sema::getDeclName(DeclPtrTy d) { 47 Decl *D = d.getAs<Decl>(); 48 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 49 return DN->getQualifiedNameAsString(); 50 return ""; 51} 52 53Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 54 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 55} 56 57/// \brief If the identifier refers to a type name within this scope, 58/// return the declaration of that type. 59/// 60/// This routine performs ordinary name lookup of the identifier II 61/// within the given scope, with optional C++ scope specifier SS, to 62/// determine whether the name refers to a type. If so, returns an 63/// opaque pointer (actually a QualType) corresponding to that 64/// type. Otherwise, returns NULL. 65/// 66/// If name lookup results in an ambiguity, this routine will complain 67/// and then return NULL. 68Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 69 Scope *S, const CXXScopeSpec *SS, 70 bool isClassName, 71 TypeTy *ObjectTypePtr) { 72 // Determine where we will perform name lookup. 73 DeclContext *LookupCtx = 0; 74 if (ObjectTypePtr) { 75 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 76 if (ObjectType->isRecordType()) 77 LookupCtx = computeDeclContext(ObjectType); 78 } else if (SS && SS->isSet()) { 79 LookupCtx = computeDeclContext(*SS, false); 80 81 if (!LookupCtx) { 82 if (isDependentScopeSpecifier(*SS)) { 83 // C++ [temp.res]p3: 84 // A qualified-id that refers to a type and in which the 85 // nested-name-specifier depends on a template-parameter (14.6.2) 86 // shall be prefixed by the keyword typename to indicate that the 87 // qualified-id denotes a type, forming an 88 // elaborated-type-specifier (7.1.5.3). 89 // 90 // We therefore do not perform any name lookup if the result would 91 // refer to a member of an unknown specialization. 92 if (!isClassName) 93 return 0; 94 95 // We know from the grammar that this name refers to a type, so build a 96 // TypenameType node to describe the type. 97 // FIXME: Record somewhere that this TypenameType node has no "typename" 98 // keyword associated with it. 99 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 100 II, SS->getRange()).getAsOpaquePtr(); 101 } 102 103 return 0; 104 } 105 106 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 107 return 0; 108 } 109 110 LookupResult Result(*this, &II, NameLoc, LookupOrdinaryName); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 return 0; 138 139 case LookupResult::Ambiguous: 140 // Recover from type-hiding ambiguities by hiding the type. We'll 141 // do the lookup again when looking for an object, and we can 142 // diagnose the error then. If we don't do this, then the error 143 // about hiding the type will be immediately followed by an error 144 // that only makes sense if the identifier was treated like a type. 145 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 146 Result.suppressDiagnostics(); 147 return 0; 148 } 149 150 // Look to see if we have a type anywhere in the list of results. 151 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 152 Res != ResEnd; ++Res) { 153 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 154 if (!IIDecl || 155 (*Res)->getLocation().getRawEncoding() < 156 IIDecl->getLocation().getRawEncoding()) 157 IIDecl = *Res; 158 } 159 } 160 161 if (!IIDecl) { 162 // None of the entities we found is a type, so there is no way 163 // to even assume that the result is a type. In this case, don't 164 // complain about the ambiguity. The parser will either try to 165 // perform this lookup again (e.g., as an object name), which 166 // will produce the ambiguity, or will complain that it expected 167 // a type name. 168 Result.suppressDiagnostics(); 169 return 0; 170 } 171 172 // We found a type within the ambiguous lookup; diagnose the 173 // ambiguity and then return that type. This might be the right 174 // answer, or it might not be, but it suppresses any attempt to 175 // perform the name lookup again. 176 break; 177 178 case LookupResult::Found: 179 IIDecl = Result.getFoundDecl(); 180 break; 181 } 182 183 assert(IIDecl && "Didn't find decl"); 184 185 QualType T; 186 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 187 DiagnoseUseOfDecl(IIDecl, NameLoc); 188 189 // C++ [temp.local]p2: 190 // Within the scope of a class template specialization or 191 // partial specialization, when the injected-class-name is 192 // not followed by a <, it is equivalent to the 193 // injected-class-name followed by the template-argument s 194 // of the class template specialization or partial 195 // specialization enclosed in <>. 196 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 197 if (RD->isInjectedClassName()) 198 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 199 T = Template->getInjectedClassNameType(Context); 200 201 if (T.isNull()) 202 T = Context.getTypeDeclType(TD); 203 204 if (SS) 205 T = getQualifiedNameType(*SS, T); 206 207 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 208 T = Context.getObjCInterfaceType(IDecl); 209 } else if (UnresolvedUsingTypenameDecl *UUDecl = 210 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 211 // FIXME: preserve source structure information. 212 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 213 } else { 214 // If it's not plausibly a type, suppress diagnostics. 215 Result.suppressDiagnostics(); 216 return 0; 217 } 218 219 return T.getAsOpaquePtr(); 220} 221 222/// isTagName() - This method is called *for error recovery purposes only* 223/// to determine if the specified name is a valid tag name ("struct foo"). If 224/// so, this returns the TST for the tag corresponding to it (TST_enum, 225/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 226/// where the user forgot to specify the tag. 227DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 228 // Do a tag name lookup in this scope. 229 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 230 LookupName(R, S, false); 231 R.suppressDiagnostics(); 232 if (R.getResultKind() == LookupResult::Found) 233 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 234 switch (TD->getTagKind()) { 235 case TagDecl::TK_struct: return DeclSpec::TST_struct; 236 case TagDecl::TK_union: return DeclSpec::TST_union; 237 case TagDecl::TK_class: return DeclSpec::TST_class; 238 case TagDecl::TK_enum: return DeclSpec::TST_enum; 239 } 240 } 241 242 return DeclSpec::TST_unspecified; 243} 244 245bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 246 SourceLocation IILoc, 247 Scope *S, 248 const CXXScopeSpec *SS, 249 TypeTy *&SuggestedType) { 250 // We don't have anything to suggest (yet). 251 SuggestedType = 0; 252 253 // FIXME: Should we move the logic that tries to recover from a missing tag 254 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 255 256 if (!SS) 257 Diag(IILoc, diag::err_unknown_typename) << &II; 258 else if (DeclContext *DC = computeDeclContext(*SS, false)) 259 Diag(IILoc, diag::err_typename_nested_not_found) 260 << &II << DC << SS->getRange(); 261 else if (isDependentScopeSpecifier(*SS)) { 262 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 263 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 264 << SourceRange(SS->getRange().getBegin(), IILoc) 265 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 266 "typename "); 267 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 268 } else { 269 assert(SS && SS->isInvalid() && 270 "Invalid scope specifier has already been diagnosed"); 271 } 272 273 return true; 274} 275 276// Determines the context to return to after temporarily entering a 277// context. This depends in an unnecessarily complicated way on the 278// exact ordering of callbacks from the parser. 279DeclContext *Sema::getContainingDC(DeclContext *DC) { 280 281 // Functions defined inline within classes aren't parsed until we've 282 // finished parsing the top-level class, so the top-level class is 283 // the context we'll need to return to. 284 if (isa<FunctionDecl>(DC)) { 285 DC = DC->getLexicalParent(); 286 287 // A function not defined within a class will always return to its 288 // lexical context. 289 if (!isa<CXXRecordDecl>(DC)) 290 return DC; 291 292 // A C++ inline method/friend is parsed *after* the topmost class 293 // it was declared in is fully parsed ("complete"); the topmost 294 // class is the context we need to return to. 295 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 296 DC = RD; 297 298 // Return the declaration context of the topmost class the inline method is 299 // declared in. 300 return DC; 301 } 302 303 if (isa<ObjCMethodDecl>(DC)) 304 return Context.getTranslationUnitDecl(); 305 306 return DC->getLexicalParent(); 307} 308 309void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 310 assert(getContainingDC(DC) == CurContext && 311 "The next DeclContext should be lexically contained in the current one."); 312 CurContext = DC; 313 S->setEntity(DC); 314} 315 316void Sema::PopDeclContext() { 317 assert(CurContext && "DeclContext imbalance!"); 318 319 CurContext = getContainingDC(CurContext); 320} 321 322/// EnterDeclaratorContext - Used when we must lookup names in the context 323/// of a declarator's nested name specifier. 324/// 325void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 326 // C++0x [basic.lookup.unqual]p13: 327 // A name used in the definition of a static data member of class 328 // X (after the qualified-id of the static member) is looked up as 329 // if the name was used in a member function of X. 330 // C++0x [basic.lookup.unqual]p14: 331 // If a variable member of a namespace is defined outside of the 332 // scope of its namespace then any name used in the definition of 333 // the variable member (after the declarator-id) is looked up as 334 // if the definition of the variable member occurred in its 335 // namespace. 336 // Both of these imply that we should push a scope whose context 337 // is the semantic context of the declaration. We can't use 338 // PushDeclContext here because that context is not necessarily 339 // lexically contained in the current context. Fortunately, 340 // the containing scope should have the appropriate information. 341 342 assert(!S->getEntity() && "scope already has entity"); 343 344#ifndef NDEBUG 345 Scope *Ancestor = S->getParent(); 346 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 347 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 348#endif 349 350 CurContext = DC; 351 S->setEntity(DC); 352} 353 354void Sema::ExitDeclaratorContext(Scope *S) { 355 assert(S->getEntity() == CurContext && "Context imbalance!"); 356 357 // Switch back to the lexical context. The safety of this is 358 // enforced by an assert in EnterDeclaratorContext. 359 Scope *Ancestor = S->getParent(); 360 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 361 CurContext = (DeclContext*) Ancestor->getEntity(); 362 363 // We don't need to do anything with the scope, which is going to 364 // disappear. 365} 366 367/// \brief Determine whether we allow overloading of the function 368/// PrevDecl with another declaration. 369/// 370/// This routine determines whether overloading is possible, not 371/// whether some new function is actually an overload. It will return 372/// true in C++ (where we can always provide overloads) or, as an 373/// extension, in C when the previous function is already an 374/// overloaded function declaration or has the "overloadable" 375/// attribute. 376static bool AllowOverloadingOfFunction(LookupResult &Previous, 377 ASTContext &Context) { 378 if (Context.getLangOptions().CPlusPlus) 379 return true; 380 381 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 382 return true; 383 384 return (Previous.getResultKind() == LookupResult::Found 385 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 386} 387 388/// Add this decl to the scope shadowed decl chains. 389void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 390 // Move up the scope chain until we find the nearest enclosing 391 // non-transparent context. The declaration will be introduced into this 392 // scope. 393 while (S->getEntity() && 394 ((DeclContext *)S->getEntity())->isTransparentContext()) 395 S = S->getParent(); 396 397 // Add scoped declarations into their context, so that they can be 398 // found later. Declarations without a context won't be inserted 399 // into any context. 400 if (AddToContext) 401 CurContext->addDecl(D); 402 403 // Out-of-line function and variable definitions should not be pushed into 404 // scope. 405 if ((isa<FunctionTemplateDecl>(D) && 406 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 407 (isa<FunctionDecl>(D) && 408 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 409 cast<FunctionDecl>(D)->isOutOfLine())) || 410 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 411 return; 412 413 // If this replaces anything in the current scope, 414 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 415 IEnd = IdResolver.end(); 416 for (; I != IEnd; ++I) { 417 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 418 S->RemoveDecl(DeclPtrTy::make(*I)); 419 IdResolver.RemoveDecl(*I); 420 421 // Should only need to replace one decl. 422 break; 423 } 424 } 425 426 S->AddDecl(DeclPtrTy::make(D)); 427 IdResolver.AddDecl(D); 428} 429 430bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 431 return IdResolver.isDeclInScope(D, Ctx, Context, S); 432} 433 434static bool isOutOfScopePreviousDeclaration(NamedDecl *, 435 DeclContext*, 436 ASTContext&); 437 438/// Filters out lookup results that don't fall within the given scope 439/// as determined by isDeclInScope. 440static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 441 DeclContext *Ctx, Scope *S, 442 bool ConsiderLinkage) { 443 LookupResult::Filter F = R.makeFilter(); 444 while (F.hasNext()) { 445 NamedDecl *D = F.next(); 446 447 if (SemaRef.isDeclInScope(D, Ctx, S)) 448 continue; 449 450 if (ConsiderLinkage && 451 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 452 continue; 453 454 F.erase(); 455 } 456 457 F.done(); 458} 459 460static bool isUsingDecl(NamedDecl *D) { 461 return isa<UsingShadowDecl>(D) || 462 isa<UnresolvedUsingTypenameDecl>(D) || 463 isa<UnresolvedUsingValueDecl>(D); 464} 465 466/// Removes using shadow declarations from the lookup results. 467static void RemoveUsingDecls(LookupResult &R) { 468 LookupResult::Filter F = R.makeFilter(); 469 while (F.hasNext()) 470 if (isUsingDecl(F.next())) 471 F.erase(); 472 473 F.done(); 474} 475 476static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 477 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 478 return false; 479 480 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 481 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 482 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 483 if (!RD->hasTrivialConstructor()) 484 return false; 485 if (!RD->hasTrivialDestructor()) 486 return false; 487 } 488 } 489 } 490 491 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 492 !isa<ImplicitParamDecl>(D) && 493 D->getDeclContext()->isFunctionOrMethod()); 494} 495 496void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 497 if (S->decl_empty()) return; 498 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 499 "Scope shouldn't contain decls!"); 500 501 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 502 I != E; ++I) { 503 Decl *TmpD = (*I).getAs<Decl>(); 504 assert(TmpD && "This decl didn't get pushed??"); 505 506 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 507 NamedDecl *D = cast<NamedDecl>(TmpD); 508 509 if (!D->getDeclName()) continue; 510 511 // Diagnose unused variables in this scope. 512 if (ShouldDiagnoseUnusedDecl(D)) 513 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 514 515 // Remove this name from our lexical scope. 516 IdResolver.RemoveDecl(D); 517 } 518} 519 520/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 521/// return 0 if one not found. 522ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 523 // The third "scope" argument is 0 since we aren't enabling lazy built-in 524 // creation from this context. 525 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 526 527 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 528} 529 530/// getNonFieldDeclScope - Retrieves the innermost scope, starting 531/// from S, where a non-field would be declared. This routine copes 532/// with the difference between C and C++ scoping rules in structs and 533/// unions. For example, the following code is well-formed in C but 534/// ill-formed in C++: 535/// @code 536/// struct S6 { 537/// enum { BAR } e; 538/// }; 539/// 540/// void test_S6() { 541/// struct S6 a; 542/// a.e = BAR; 543/// } 544/// @endcode 545/// For the declaration of BAR, this routine will return a different 546/// scope. The scope S will be the scope of the unnamed enumeration 547/// within S6. In C++, this routine will return the scope associated 548/// with S6, because the enumeration's scope is a transparent 549/// context but structures can contain non-field names. In C, this 550/// routine will return the translation unit scope, since the 551/// enumeration's scope is a transparent context and structures cannot 552/// contain non-field names. 553Scope *Sema::getNonFieldDeclScope(Scope *S) { 554 while (((S->getFlags() & Scope::DeclScope) == 0) || 555 (S->getEntity() && 556 ((DeclContext *)S->getEntity())->isTransparentContext()) || 557 (S->isClassScope() && !getLangOptions().CPlusPlus)) 558 S = S->getParent(); 559 return S; 560} 561 562void Sema::InitBuiltinVaListType() { 563 if (!Context.getBuiltinVaListType().isNull()) 564 return; 565 566 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 567 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 568 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 569 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 570} 571 572/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 573/// file scope. lazily create a decl for it. ForRedeclaration is true 574/// if we're creating this built-in in anticipation of redeclaring the 575/// built-in. 576NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 577 Scope *S, bool ForRedeclaration, 578 SourceLocation Loc) { 579 Builtin::ID BID = (Builtin::ID)bid; 580 581 if (Context.BuiltinInfo.hasVAListUse(BID)) 582 InitBuiltinVaListType(); 583 584 ASTContext::GetBuiltinTypeError Error; 585 QualType R = Context.GetBuiltinType(BID, Error); 586 switch (Error) { 587 case ASTContext::GE_None: 588 // Okay 589 break; 590 591 case ASTContext::GE_Missing_stdio: 592 if (ForRedeclaration) 593 Diag(Loc, diag::err_implicit_decl_requires_stdio) 594 << Context.BuiltinInfo.GetName(BID); 595 return 0; 596 597 case ASTContext::GE_Missing_setjmp: 598 if (ForRedeclaration) 599 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 600 << Context.BuiltinInfo.GetName(BID); 601 return 0; 602 } 603 604 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 605 Diag(Loc, diag::ext_implicit_lib_function_decl) 606 << Context.BuiltinInfo.GetName(BID) 607 << R; 608 if (Context.BuiltinInfo.getHeaderName(BID) && 609 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 610 != Diagnostic::Ignored) 611 Diag(Loc, diag::note_please_include_header) 612 << Context.BuiltinInfo.getHeaderName(BID) 613 << Context.BuiltinInfo.GetName(BID); 614 } 615 616 FunctionDecl *New = FunctionDecl::Create(Context, 617 Context.getTranslationUnitDecl(), 618 Loc, II, R, /*TInfo=*/0, 619 FunctionDecl::Extern, false, 620 /*hasPrototype=*/true); 621 New->setImplicit(); 622 623 // Create Decl objects for each parameter, adding them to the 624 // FunctionDecl. 625 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 626 llvm::SmallVector<ParmVarDecl*, 16> Params; 627 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 628 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 629 FT->getArgType(i), /*TInfo=*/0, 630 VarDecl::None, 0)); 631 New->setParams(Context, Params.data(), Params.size()); 632 } 633 634 AddKnownFunctionAttributes(New); 635 636 // TUScope is the translation-unit scope to insert this function into. 637 // FIXME: This is hideous. We need to teach PushOnScopeChains to 638 // relate Scopes to DeclContexts, and probably eliminate CurContext 639 // entirely, but we're not there yet. 640 DeclContext *SavedContext = CurContext; 641 CurContext = Context.getTranslationUnitDecl(); 642 PushOnScopeChains(New, TUScope); 643 CurContext = SavedContext; 644 return New; 645} 646 647/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 648/// same name and scope as a previous declaration 'Old'. Figure out 649/// how to resolve this situation, merging decls or emitting 650/// diagnostics as appropriate. If there was an error, set New to be invalid. 651/// 652void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 653 // If the new decl is known invalid already, don't bother doing any 654 // merging checks. 655 if (New->isInvalidDecl()) return; 656 657 // Allow multiple definitions for ObjC built-in typedefs. 658 // FIXME: Verify the underlying types are equivalent! 659 if (getLangOptions().ObjC1) { 660 const IdentifierInfo *TypeID = New->getIdentifier(); 661 switch (TypeID->getLength()) { 662 default: break; 663 case 2: 664 if (!TypeID->isStr("id")) 665 break; 666 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 667 // Install the built-in type for 'id', ignoring the current definition. 668 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 669 return; 670 case 5: 671 if (!TypeID->isStr("Class")) 672 break; 673 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 674 // Install the built-in type for 'Class', ignoring the current definition. 675 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 676 return; 677 case 3: 678 if (!TypeID->isStr("SEL")) 679 break; 680 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 681 // Install the built-in type for 'SEL', ignoring the current definition. 682 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 683 return; 684 case 8: 685 if (!TypeID->isStr("Protocol")) 686 break; 687 Context.setObjCProtoType(New->getUnderlyingType()); 688 return; 689 } 690 // Fall through - the typedef name was not a builtin type. 691 } 692 693 // Verify the old decl was also a type. 694 TypeDecl *Old = 0; 695 if (!OldDecls.isSingleResult() || 696 !(Old = dyn_cast<TypeDecl>(OldDecls.getFoundDecl()))) { 697 Diag(New->getLocation(), diag::err_redefinition_different_kind) 698 << New->getDeclName(); 699 700 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 701 if (OldD->getLocation().isValid()) 702 Diag(OldD->getLocation(), diag::note_previous_definition); 703 704 return New->setInvalidDecl(); 705 } 706 707 // If the old declaration is invalid, just give up here. 708 if (Old->isInvalidDecl()) 709 return New->setInvalidDecl(); 710 711 // Determine the "old" type we'll use for checking and diagnostics. 712 QualType OldType; 713 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 714 OldType = OldTypedef->getUnderlyingType(); 715 else 716 OldType = Context.getTypeDeclType(Old); 717 718 // If the typedef types are not identical, reject them in all languages and 719 // with any extensions enabled. 720 721 if (OldType != New->getUnderlyingType() && 722 Context.getCanonicalType(OldType) != 723 Context.getCanonicalType(New->getUnderlyingType())) { 724 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 725 << New->getUnderlyingType() << OldType; 726 if (Old->getLocation().isValid()) 727 Diag(Old->getLocation(), diag::note_previous_definition); 728 return New->setInvalidDecl(); 729 } 730 731 if (getLangOptions().Microsoft) 732 return; 733 734 // C++ [dcl.typedef]p2: 735 // In a given non-class scope, a typedef specifier can be used to 736 // redefine the name of any type declared in that scope to refer 737 // to the type to which it already refers. 738 if (getLangOptions().CPlusPlus) { 739 if (!isa<CXXRecordDecl>(CurContext)) 740 return; 741 Diag(New->getLocation(), diag::err_redefinition) 742 << New->getDeclName(); 743 Diag(Old->getLocation(), diag::note_previous_definition); 744 return New->setInvalidDecl(); 745 } 746 747 // If we have a redefinition of a typedef in C, emit a warning. This warning 748 // is normally mapped to an error, but can be controlled with 749 // -Wtypedef-redefinition. If either the original or the redefinition is 750 // in a system header, don't emit this for compatibility with GCC. 751 if (PP.getDiagnostics().getSuppressSystemWarnings() && 752 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 753 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 754 return; 755 756 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 757 << New->getDeclName(); 758 Diag(Old->getLocation(), diag::note_previous_definition); 759 return; 760} 761 762/// DeclhasAttr - returns true if decl Declaration already has the target 763/// attribute. 764static bool 765DeclHasAttr(const Decl *decl, const Attr *target) { 766 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 767 if (attr->getKind() == target->getKind()) 768 return true; 769 770 return false; 771} 772 773/// MergeAttributes - append attributes from the Old decl to the New one. 774static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 775 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 776 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 777 Attr *NewAttr = attr->clone(C); 778 NewAttr->setInherited(true); 779 New->addAttr(NewAttr); 780 } 781 } 782} 783 784/// Used in MergeFunctionDecl to keep track of function parameters in 785/// C. 786struct GNUCompatibleParamWarning { 787 ParmVarDecl *OldParm; 788 ParmVarDecl *NewParm; 789 QualType PromotedType; 790}; 791 792 793/// getSpecialMember - get the special member enum for a method. 794static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 795 const CXXMethodDecl *MD) { 796 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 797 if (Ctor->isDefaultConstructor()) 798 return Sema::CXXDefaultConstructor; 799 if (Ctor->isCopyConstructor(Ctx)) 800 return Sema::CXXCopyConstructor; 801 } 802 803 if (isa<CXXDestructorDecl>(MD)) 804 return Sema::CXXDestructor; 805 806 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 807 return Sema::CXXCopyAssignment; 808} 809 810/// MergeFunctionDecl - We just parsed a function 'New' from 811/// declarator D which has the same name and scope as a previous 812/// declaration 'Old'. Figure out how to resolve this situation, 813/// merging decls or emitting diagnostics as appropriate. 814/// 815/// In C++, New and Old must be declarations that are not 816/// overloaded. Use IsOverload to determine whether New and Old are 817/// overloaded, and to select the Old declaration that New should be 818/// merged with. 819/// 820/// Returns true if there was an error, false otherwise. 821bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 822 // Verify the old decl was also a function. 823 FunctionDecl *Old = 0; 824 if (FunctionTemplateDecl *OldFunctionTemplate 825 = dyn_cast<FunctionTemplateDecl>(OldD)) 826 Old = OldFunctionTemplate->getTemplatedDecl(); 827 else 828 Old = dyn_cast<FunctionDecl>(OldD); 829 if (!Old) { 830 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 831 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 832 Diag(Shadow->getTargetDecl()->getLocation(), 833 diag::note_using_decl_target); 834 Diag(Shadow->getUsingDecl()->getLocation(), 835 diag::note_using_decl) << 0; 836 return true; 837 } 838 839 Diag(New->getLocation(), diag::err_redefinition_different_kind) 840 << New->getDeclName(); 841 Diag(OldD->getLocation(), diag::note_previous_definition); 842 return true; 843 } 844 845 // Determine whether the previous declaration was a definition, 846 // implicit declaration, or a declaration. 847 diag::kind PrevDiag; 848 if (Old->isThisDeclarationADefinition()) 849 PrevDiag = diag::note_previous_definition; 850 else if (Old->isImplicit()) 851 PrevDiag = diag::note_previous_implicit_declaration; 852 else 853 PrevDiag = diag::note_previous_declaration; 854 855 QualType OldQType = Context.getCanonicalType(Old->getType()); 856 QualType NewQType = Context.getCanonicalType(New->getType()); 857 858 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 859 New->getStorageClass() == FunctionDecl::Static && 860 Old->getStorageClass() != FunctionDecl::Static) { 861 Diag(New->getLocation(), diag::err_static_non_static) 862 << New; 863 Diag(Old->getLocation(), PrevDiag); 864 return true; 865 } 866 867 if (getLangOptions().CPlusPlus) { 868 // (C++98 13.1p2): 869 // Certain function declarations cannot be overloaded: 870 // -- Function declarations that differ only in the return type 871 // cannot be overloaded. 872 QualType OldReturnType 873 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 874 QualType NewReturnType 875 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 876 if (OldReturnType != NewReturnType) { 877 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 878 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 879 return true; 880 } 881 882 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 883 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 884 if (OldMethod && NewMethod) { 885 if (!NewMethod->getFriendObjectKind() && 886 NewMethod->getLexicalDeclContext()->isRecord()) { 887 // -- Member function declarations with the same name and the 888 // same parameter types cannot be overloaded if any of them 889 // is a static member function declaration. 890 if (OldMethod->isStatic() || NewMethod->isStatic()) { 891 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 892 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 893 return true; 894 } 895 896 // C++ [class.mem]p1: 897 // [...] A member shall not be declared twice in the 898 // member-specification, except that a nested class or member 899 // class template can be declared and then later defined. 900 unsigned NewDiag; 901 if (isa<CXXConstructorDecl>(OldMethod)) 902 NewDiag = diag::err_constructor_redeclared; 903 else if (isa<CXXDestructorDecl>(NewMethod)) 904 NewDiag = diag::err_destructor_redeclared; 905 else if (isa<CXXConversionDecl>(NewMethod)) 906 NewDiag = diag::err_conv_function_redeclared; 907 else 908 NewDiag = diag::err_member_redeclared; 909 910 Diag(New->getLocation(), NewDiag); 911 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 912 } else { 913 if (OldMethod->isImplicit()) { 914 Diag(NewMethod->getLocation(), 915 diag::err_definition_of_implicitly_declared_member) 916 << New << getSpecialMember(Context, OldMethod); 917 918 Diag(OldMethod->getLocation(), 919 diag::note_previous_implicit_declaration); 920 return true; 921 } 922 } 923 } 924 925 // (C++98 8.3.5p3): 926 // All declarations for a function shall agree exactly in both the 927 // return type and the parameter-type-list. 928 if (OldQType == NewQType) 929 return MergeCompatibleFunctionDecls(New, Old); 930 931 // Fall through for conflicting redeclarations and redefinitions. 932 } 933 934 // C: Function types need to be compatible, not identical. This handles 935 // duplicate function decls like "void f(int); void f(enum X);" properly. 936 if (!getLangOptions().CPlusPlus && 937 Context.typesAreCompatible(OldQType, NewQType)) { 938 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 939 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 940 const FunctionProtoType *OldProto = 0; 941 if (isa<FunctionNoProtoType>(NewFuncType) && 942 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 943 // The old declaration provided a function prototype, but the 944 // new declaration does not. Merge in the prototype. 945 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 946 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 947 OldProto->arg_type_end()); 948 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 949 ParamTypes.data(), ParamTypes.size(), 950 OldProto->isVariadic(), 951 OldProto->getTypeQuals()); 952 New->setType(NewQType); 953 New->setHasInheritedPrototype(); 954 955 // Synthesize a parameter for each argument type. 956 llvm::SmallVector<ParmVarDecl*, 16> Params; 957 for (FunctionProtoType::arg_type_iterator 958 ParamType = OldProto->arg_type_begin(), 959 ParamEnd = OldProto->arg_type_end(); 960 ParamType != ParamEnd; ++ParamType) { 961 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 962 SourceLocation(), 0, 963 *ParamType, /*TInfo=*/0, 964 VarDecl::None, 0); 965 Param->setImplicit(); 966 Params.push_back(Param); 967 } 968 969 New->setParams(Context, Params.data(), Params.size()); 970 } 971 972 return MergeCompatibleFunctionDecls(New, Old); 973 } 974 975 // GNU C permits a K&R definition to follow a prototype declaration 976 // if the declared types of the parameters in the K&R definition 977 // match the types in the prototype declaration, even when the 978 // promoted types of the parameters from the K&R definition differ 979 // from the types in the prototype. GCC then keeps the types from 980 // the prototype. 981 // 982 // If a variadic prototype is followed by a non-variadic K&R definition, 983 // the K&R definition becomes variadic. This is sort of an edge case, but 984 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 985 // C99 6.9.1p8. 986 if (!getLangOptions().CPlusPlus && 987 Old->hasPrototype() && !New->hasPrototype() && 988 New->getType()->getAs<FunctionProtoType>() && 989 Old->getNumParams() == New->getNumParams()) { 990 llvm::SmallVector<QualType, 16> ArgTypes; 991 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 992 const FunctionProtoType *OldProto 993 = Old->getType()->getAs<FunctionProtoType>(); 994 const FunctionProtoType *NewProto 995 = New->getType()->getAs<FunctionProtoType>(); 996 997 // Determine whether this is the GNU C extension. 998 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 999 NewProto->getResultType()); 1000 bool LooseCompatible = !MergedReturn.isNull(); 1001 for (unsigned Idx = 0, End = Old->getNumParams(); 1002 LooseCompatible && Idx != End; ++Idx) { 1003 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1004 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1005 if (Context.typesAreCompatible(OldParm->getType(), 1006 NewProto->getArgType(Idx))) { 1007 ArgTypes.push_back(NewParm->getType()); 1008 } else if (Context.typesAreCompatible(OldParm->getType(), 1009 NewParm->getType())) { 1010 GNUCompatibleParamWarning Warn 1011 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1012 Warnings.push_back(Warn); 1013 ArgTypes.push_back(NewParm->getType()); 1014 } else 1015 LooseCompatible = false; 1016 } 1017 1018 if (LooseCompatible) { 1019 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1020 Diag(Warnings[Warn].NewParm->getLocation(), 1021 diag::ext_param_promoted_not_compatible_with_prototype) 1022 << Warnings[Warn].PromotedType 1023 << Warnings[Warn].OldParm->getType(); 1024 Diag(Warnings[Warn].OldParm->getLocation(), 1025 diag::note_previous_declaration); 1026 } 1027 1028 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1029 ArgTypes.size(), 1030 OldProto->isVariadic(), 0)); 1031 return MergeCompatibleFunctionDecls(New, Old); 1032 } 1033 1034 // Fall through to diagnose conflicting types. 1035 } 1036 1037 // A function that has already been declared has been redeclared or defined 1038 // with a different type- show appropriate diagnostic 1039 if (unsigned BuiltinID = Old->getBuiltinID()) { 1040 // The user has declared a builtin function with an incompatible 1041 // signature. 1042 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1043 // The function the user is redeclaring is a library-defined 1044 // function like 'malloc' or 'printf'. Warn about the 1045 // redeclaration, then pretend that we don't know about this 1046 // library built-in. 1047 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1048 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1049 << Old << Old->getType(); 1050 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1051 Old->setInvalidDecl(); 1052 return false; 1053 } 1054 1055 PrevDiag = diag::note_previous_builtin_declaration; 1056 } 1057 1058 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1059 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1060 return true; 1061} 1062 1063/// \brief Completes the merge of two function declarations that are 1064/// known to be compatible. 1065/// 1066/// This routine handles the merging of attributes and other 1067/// properties of function declarations form the old declaration to 1068/// the new declaration, once we know that New is in fact a 1069/// redeclaration of Old. 1070/// 1071/// \returns false 1072bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1073 // Merge the attributes 1074 MergeAttributes(New, Old, Context); 1075 1076 // Merge the storage class. 1077 if (Old->getStorageClass() != FunctionDecl::Extern && 1078 Old->getStorageClass() != FunctionDecl::None) 1079 New->setStorageClass(Old->getStorageClass()); 1080 1081 // Merge "pure" flag. 1082 if (Old->isPure()) 1083 New->setPure(); 1084 1085 // Merge the "deleted" flag. 1086 if (Old->isDeleted()) 1087 New->setDeleted(); 1088 1089 if (getLangOptions().CPlusPlus) 1090 return MergeCXXFunctionDecl(New, Old); 1091 1092 return false; 1093} 1094 1095/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1096/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1097/// situation, merging decls or emitting diagnostics as appropriate. 1098/// 1099/// Tentative definition rules (C99 6.9.2p2) are checked by 1100/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1101/// definitions here, since the initializer hasn't been attached. 1102/// 1103void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1104 // If the new decl is already invalid, don't do any other checking. 1105 if (New->isInvalidDecl()) 1106 return; 1107 1108 // Verify the old decl was also a variable. 1109 VarDecl *Old = 0; 1110 if (!Previous.isSingleResult() || 1111 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1112 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1113 << New->getDeclName(); 1114 Diag(Previous.getRepresentativeDecl()->getLocation(), 1115 diag::note_previous_definition); 1116 return New->setInvalidDecl(); 1117 } 1118 1119 MergeAttributes(New, Old, Context); 1120 1121 // Merge the types 1122 QualType MergedT; 1123 if (getLangOptions().CPlusPlus) { 1124 if (Context.hasSameType(New->getType(), Old->getType())) 1125 MergedT = New->getType(); 1126 // C++ [basic.link]p10: 1127 // [...] the types specified by all declarations referring to a given 1128 // object or function shall be identical, except that declarations for an 1129 // array object can specify array types that differ by the presence or 1130 // absence of a major array bound (8.3.4). 1131 else if (Old->getType()->isIncompleteArrayType() && 1132 New->getType()->isArrayType()) { 1133 CanQual<ArrayType> OldArray 1134 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1135 CanQual<ArrayType> NewArray 1136 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1137 if (OldArray->getElementType() == NewArray->getElementType()) 1138 MergedT = New->getType(); 1139 } else if (Old->getType()->isArrayType() && 1140 New->getType()->isIncompleteArrayType()) { 1141 CanQual<ArrayType> OldArray 1142 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1143 CanQual<ArrayType> NewArray 1144 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1145 if (OldArray->getElementType() == NewArray->getElementType()) 1146 MergedT = Old->getType(); 1147 } 1148 } else { 1149 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1150 } 1151 if (MergedT.isNull()) { 1152 Diag(New->getLocation(), diag::err_redefinition_different_type) 1153 << New->getDeclName(); 1154 Diag(Old->getLocation(), diag::note_previous_definition); 1155 return New->setInvalidDecl(); 1156 } 1157 New->setType(MergedT); 1158 1159 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1160 if (New->getStorageClass() == VarDecl::Static && 1161 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1162 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1163 Diag(Old->getLocation(), diag::note_previous_definition); 1164 return New->setInvalidDecl(); 1165 } 1166 // C99 6.2.2p4: 1167 // For an identifier declared with the storage-class specifier 1168 // extern in a scope in which a prior declaration of that 1169 // identifier is visible,23) if the prior declaration specifies 1170 // internal or external linkage, the linkage of the identifier at 1171 // the later declaration is the same as the linkage specified at 1172 // the prior declaration. If no prior declaration is visible, or 1173 // if the prior declaration specifies no linkage, then the 1174 // identifier has external linkage. 1175 if (New->hasExternalStorage() && Old->hasLinkage()) 1176 /* Okay */; 1177 else if (New->getStorageClass() != VarDecl::Static && 1178 Old->getStorageClass() == VarDecl::Static) { 1179 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1180 Diag(Old->getLocation(), diag::note_previous_definition); 1181 return New->setInvalidDecl(); 1182 } 1183 1184 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1185 1186 // FIXME: The test for external storage here seems wrong? We still 1187 // need to check for mismatches. 1188 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1189 // Don't complain about out-of-line definitions of static members. 1190 !(Old->getLexicalDeclContext()->isRecord() && 1191 !New->getLexicalDeclContext()->isRecord())) { 1192 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1193 Diag(Old->getLocation(), diag::note_previous_definition); 1194 return New->setInvalidDecl(); 1195 } 1196 1197 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1198 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1199 Diag(Old->getLocation(), diag::note_previous_definition); 1200 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1201 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1202 Diag(Old->getLocation(), diag::note_previous_definition); 1203 } 1204 1205 // Keep a chain of previous declarations. 1206 New->setPreviousDeclaration(Old); 1207} 1208 1209/// CheckFallThrough - Check that we don't fall off the end of a 1210/// Statement that should return a value. 1211/// 1212/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1213/// MaybeFallThrough iff we might or might not fall off the end, 1214/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1215/// return. We assume NeverFallThrough iff we never fall off the end of the 1216/// statement but we may return. We assume that functions not marked noreturn 1217/// will return. 1218Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1219 // FIXME: Eventually share this CFG object when we have other warnings based 1220 // of the CFG. This can be done using AnalysisContext. 1221 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1222 1223 // FIXME: They should never return 0, fix that, delete this code. 1224 if (cfg == 0) 1225 // FIXME: This should be NeverFallThrough 1226 return NeverFallThroughOrReturn; 1227 // The CFG leaves in dead things, and we don't want to dead code paths to 1228 // confuse us, so we mark all live things first. 1229 std::queue<CFGBlock*> workq; 1230 llvm::BitVector live(cfg->getNumBlockIDs()); 1231 // Prep work queue 1232 workq.push(&cfg->getEntry()); 1233 // Solve 1234 while (!workq.empty()) { 1235 CFGBlock *item = workq.front(); 1236 workq.pop(); 1237 live.set(item->getBlockID()); 1238 for (CFGBlock::succ_iterator I=item->succ_begin(), 1239 E=item->succ_end(); 1240 I != E; 1241 ++I) { 1242 if ((*I) && !live[(*I)->getBlockID()]) { 1243 live.set((*I)->getBlockID()); 1244 workq.push(*I); 1245 } 1246 } 1247 } 1248 1249 // Now we know what is live, we check the live precessors of the exit block 1250 // and look for fall through paths, being careful to ignore normal returns, 1251 // and exceptional paths. 1252 bool HasLiveReturn = false; 1253 bool HasFakeEdge = false; 1254 bool HasPlainEdge = false; 1255 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1256 E = cfg->getExit().pred_end(); 1257 I != E; 1258 ++I) { 1259 CFGBlock& B = **I; 1260 if (!live[B.getBlockID()]) 1261 continue; 1262 if (B.size() == 0) { 1263 // A labeled empty statement, or the entry block... 1264 HasPlainEdge = true; 1265 continue; 1266 } 1267 Stmt *S = B[B.size()-1]; 1268 if (isa<ReturnStmt>(S)) { 1269 HasLiveReturn = true; 1270 continue; 1271 } 1272 if (isa<ObjCAtThrowStmt>(S)) { 1273 HasFakeEdge = true; 1274 continue; 1275 } 1276 if (isa<CXXThrowExpr>(S)) { 1277 HasFakeEdge = true; 1278 continue; 1279 } 1280 bool NoReturnEdge = false; 1281 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1282 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1283 if (CEE->getType().getNoReturnAttr()) { 1284 NoReturnEdge = true; 1285 HasFakeEdge = true; 1286 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1287 ValueDecl *VD = DRE->getDecl(); 1288 if (VD->hasAttr<NoReturnAttr>()) { 1289 NoReturnEdge = true; 1290 HasFakeEdge = true; 1291 } 1292 } 1293 } 1294 // FIXME: Add noreturn message sends. 1295 if (NoReturnEdge == false) 1296 HasPlainEdge = true; 1297 } 1298 if (!HasPlainEdge) { 1299 if (HasLiveReturn) 1300 return NeverFallThrough; 1301 return NeverFallThroughOrReturn; 1302 } 1303 if (HasFakeEdge || HasLiveReturn) 1304 return MaybeFallThrough; 1305 // This says AlwaysFallThrough for calls to functions that are not marked 1306 // noreturn, that don't return. If people would like this warning to be more 1307 // accurate, such functions should be marked as noreturn. 1308 return AlwaysFallThrough; 1309} 1310 1311/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1312/// function that should return a value. Check that we don't fall off the end 1313/// of a noreturn function. We assume that functions and blocks not marked 1314/// noreturn will return. 1315void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1316 // FIXME: Would be nice if we had a better way to control cascading errors, 1317 // but for now, avoid them. The problem is that when Parse sees: 1318 // int foo() { return a; } 1319 // The return is eaten and the Sema code sees just: 1320 // int foo() { } 1321 // which this code would then warn about. 1322 if (getDiagnostics().hasErrorOccurred()) 1323 return; 1324 1325 bool ReturnsVoid = false; 1326 bool HasNoReturn = false; 1327 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1328 // If the result type of the function is a dependent type, we don't know 1329 // whether it will be void or not, so don't 1330 if (FD->getResultType()->isDependentType()) 1331 return; 1332 if (FD->getResultType()->isVoidType()) 1333 ReturnsVoid = true; 1334 if (FD->hasAttr<NoReturnAttr>()) 1335 HasNoReturn = true; 1336 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1337 if (MD->getResultType()->isVoidType()) 1338 ReturnsVoid = true; 1339 if (MD->hasAttr<NoReturnAttr>()) 1340 HasNoReturn = true; 1341 } 1342 1343 // Short circuit for compilation speed. 1344 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1345 == Diagnostic::Ignored || ReturnsVoid) 1346 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1347 == Diagnostic::Ignored || !HasNoReturn) 1348 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1349 == Diagnostic::Ignored || !ReturnsVoid)) 1350 return; 1351 // FIXME: Function try block 1352 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1353 switch (CheckFallThrough(Body)) { 1354 case MaybeFallThrough: 1355 if (HasNoReturn) 1356 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1357 else if (!ReturnsVoid) 1358 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1359 break; 1360 case AlwaysFallThrough: 1361 if (HasNoReturn) 1362 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1363 else if (!ReturnsVoid) 1364 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1365 break; 1366 case NeverFallThroughOrReturn: 1367 if (ReturnsVoid && !HasNoReturn) 1368 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1369 break; 1370 case NeverFallThrough: 1371 break; 1372 } 1373 } 1374} 1375 1376/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1377/// that should return a value. Check that we don't fall off the end of a 1378/// noreturn block. We assume that functions and blocks not marked noreturn 1379/// will return. 1380void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1381 // FIXME: Would be nice if we had a better way to control cascading errors, 1382 // but for now, avoid them. The problem is that when Parse sees: 1383 // int foo() { return a; } 1384 // The return is eaten and the Sema code sees just: 1385 // int foo() { } 1386 // which this code would then warn about. 1387 if (getDiagnostics().hasErrorOccurred()) 1388 return; 1389 bool ReturnsVoid = false; 1390 bool HasNoReturn = false; 1391 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1392 if (FT->getResultType()->isVoidType()) 1393 ReturnsVoid = true; 1394 if (FT->getNoReturnAttr()) 1395 HasNoReturn = true; 1396 } 1397 1398 // Short circuit for compilation speed. 1399 if (ReturnsVoid 1400 && !HasNoReturn 1401 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1402 == Diagnostic::Ignored || !ReturnsVoid)) 1403 return; 1404 // FIXME: Funtion try block 1405 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1406 switch (CheckFallThrough(Body)) { 1407 case MaybeFallThrough: 1408 if (HasNoReturn) 1409 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1410 else if (!ReturnsVoid) 1411 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1412 break; 1413 case AlwaysFallThrough: 1414 if (HasNoReturn) 1415 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1416 else if (!ReturnsVoid) 1417 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1418 break; 1419 case NeverFallThroughOrReturn: 1420 if (ReturnsVoid) 1421 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1422 break; 1423 case NeverFallThrough: 1424 break; 1425 } 1426 } 1427} 1428 1429/// CheckParmsForFunctionDef - Check that the parameters of the given 1430/// function are appropriate for the definition of a function. This 1431/// takes care of any checks that cannot be performed on the 1432/// declaration itself, e.g., that the types of each of the function 1433/// parameters are complete. 1434bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1435 bool HasInvalidParm = false; 1436 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1437 ParmVarDecl *Param = FD->getParamDecl(p); 1438 1439 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1440 // function declarator that is part of a function definition of 1441 // that function shall not have incomplete type. 1442 // 1443 // This is also C++ [dcl.fct]p6. 1444 if (!Param->isInvalidDecl() && 1445 RequireCompleteType(Param->getLocation(), Param->getType(), 1446 diag::err_typecheck_decl_incomplete_type)) { 1447 Param->setInvalidDecl(); 1448 HasInvalidParm = true; 1449 } 1450 1451 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1452 // declaration of each parameter shall include an identifier. 1453 if (Param->getIdentifier() == 0 && 1454 !Param->isImplicit() && 1455 !getLangOptions().CPlusPlus) 1456 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1457 } 1458 1459 return HasInvalidParm; 1460} 1461 1462/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1463/// no declarator (e.g. "struct foo;") is parsed. 1464Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1465 // FIXME: Error on auto/register at file scope 1466 // FIXME: Error on inline/virtual/explicit 1467 // FIXME: Warn on useless __thread 1468 // FIXME: Warn on useless const/volatile 1469 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1470 // FIXME: Warn on useless attributes 1471 Decl *TagD = 0; 1472 TagDecl *Tag = 0; 1473 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1474 DS.getTypeSpecType() == DeclSpec::TST_struct || 1475 DS.getTypeSpecType() == DeclSpec::TST_union || 1476 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1477 TagD = static_cast<Decl *>(DS.getTypeRep()); 1478 1479 if (!TagD) // We probably had an error 1480 return DeclPtrTy(); 1481 1482 // Note that the above type specs guarantee that the 1483 // type rep is a Decl, whereas in many of the others 1484 // it's a Type. 1485 Tag = dyn_cast<TagDecl>(TagD); 1486 } 1487 1488 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1489 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1490 // or incomplete types shall not be restrict-qualified." 1491 if (TypeQuals & DeclSpec::TQ_restrict) 1492 Diag(DS.getRestrictSpecLoc(), 1493 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1494 << DS.getSourceRange(); 1495 } 1496 1497 if (DS.isFriendSpecified()) { 1498 // If we're dealing with a class template decl, assume that the 1499 // template routines are handling it. 1500 if (TagD && isa<ClassTemplateDecl>(TagD)) 1501 return DeclPtrTy(); 1502 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1503 } 1504 1505 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1506 // If there are attributes in the DeclSpec, apply them to the record. 1507 if (const AttributeList *AL = DS.getAttributes()) 1508 ProcessDeclAttributeList(S, Record, AL); 1509 1510 if (!Record->getDeclName() && Record->isDefinition() && 1511 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1512 if (getLangOptions().CPlusPlus || 1513 Record->getDeclContext()->isRecord()) 1514 return BuildAnonymousStructOrUnion(S, DS, Record); 1515 1516 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1517 << DS.getSourceRange(); 1518 } 1519 1520 // Microsoft allows unnamed struct/union fields. Don't complain 1521 // about them. 1522 // FIXME: Should we support Microsoft's extensions in this area? 1523 if (Record->getDeclName() && getLangOptions().Microsoft) 1524 return DeclPtrTy::make(Tag); 1525 } 1526 1527 if (!DS.isMissingDeclaratorOk() && 1528 DS.getTypeSpecType() != DeclSpec::TST_error) { 1529 // Warn about typedefs of enums without names, since this is an 1530 // extension in both Microsoft an GNU. 1531 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1532 Tag && isa<EnumDecl>(Tag)) { 1533 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1534 << DS.getSourceRange(); 1535 return DeclPtrTy::make(Tag); 1536 } 1537 1538 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1539 << DS.getSourceRange(); 1540 return DeclPtrTy(); 1541 } 1542 1543 return DeclPtrTy::make(Tag); 1544} 1545 1546/// We are trying to inject an anonymous member into the given scope; 1547/// check if there's an existing declaration that can't be overloaded. 1548/// 1549/// \return true if this is a forbidden redeclaration 1550static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1551 Scope *S, 1552 DeclarationName Name, 1553 SourceLocation NameLoc, 1554 unsigned diagnostic) { 1555 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1556 Sema::ForRedeclaration); 1557 if (!SemaRef.LookupName(R, S)) return false; 1558 1559 if (R.getAsSingle<TagDecl>()) 1560 return false; 1561 1562 // Pick a representative declaration. 1563 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1564 1565 SemaRef.Diag(NameLoc, diagnostic) << Name; 1566 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1567 1568 return true; 1569} 1570 1571/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1572/// anonymous struct or union AnonRecord into the owning context Owner 1573/// and scope S. This routine will be invoked just after we realize 1574/// that an unnamed union or struct is actually an anonymous union or 1575/// struct, e.g., 1576/// 1577/// @code 1578/// union { 1579/// int i; 1580/// float f; 1581/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1582/// // f into the surrounding scope.x 1583/// @endcode 1584/// 1585/// This routine is recursive, injecting the names of nested anonymous 1586/// structs/unions into the owning context and scope as well. 1587bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1588 RecordDecl *AnonRecord) { 1589 unsigned diagKind 1590 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1591 : diag::err_anonymous_struct_member_redecl; 1592 1593 bool Invalid = false; 1594 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1595 FEnd = AnonRecord->field_end(); 1596 F != FEnd; ++F) { 1597 if ((*F)->getDeclName()) { 1598 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1599 (*F)->getLocation(), diagKind)) { 1600 // C++ [class.union]p2: 1601 // The names of the members of an anonymous union shall be 1602 // distinct from the names of any other entity in the 1603 // scope in which the anonymous union is declared. 1604 Invalid = true; 1605 } else { 1606 // C++ [class.union]p2: 1607 // For the purpose of name lookup, after the anonymous union 1608 // definition, the members of the anonymous union are 1609 // considered to have been defined in the scope in which the 1610 // anonymous union is declared. 1611 Owner->makeDeclVisibleInContext(*F); 1612 S->AddDecl(DeclPtrTy::make(*F)); 1613 IdResolver.AddDecl(*F); 1614 } 1615 } else if (const RecordType *InnerRecordType 1616 = (*F)->getType()->getAs<RecordType>()) { 1617 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1618 if (InnerRecord->isAnonymousStructOrUnion()) 1619 Invalid = Invalid || 1620 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1621 } 1622 } 1623 1624 return Invalid; 1625} 1626 1627/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1628/// anonymous structure or union. Anonymous unions are a C++ feature 1629/// (C++ [class.union]) and a GNU C extension; anonymous structures 1630/// are a GNU C and GNU C++ extension. 1631Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1632 RecordDecl *Record) { 1633 DeclContext *Owner = Record->getDeclContext(); 1634 1635 // Diagnose whether this anonymous struct/union is an extension. 1636 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1637 Diag(Record->getLocation(), diag::ext_anonymous_union); 1638 else if (!Record->isUnion()) 1639 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1640 1641 // C and C++ require different kinds of checks for anonymous 1642 // structs/unions. 1643 bool Invalid = false; 1644 if (getLangOptions().CPlusPlus) { 1645 const char* PrevSpec = 0; 1646 unsigned DiagID; 1647 // C++ [class.union]p3: 1648 // Anonymous unions declared in a named namespace or in the 1649 // global namespace shall be declared static. 1650 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1651 (isa<TranslationUnitDecl>(Owner) || 1652 (isa<NamespaceDecl>(Owner) && 1653 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1654 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1655 Invalid = true; 1656 1657 // Recover by adding 'static'. 1658 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1659 PrevSpec, DiagID); 1660 } 1661 // C++ [class.union]p3: 1662 // A storage class is not allowed in a declaration of an 1663 // anonymous union in a class scope. 1664 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1665 isa<RecordDecl>(Owner)) { 1666 Diag(DS.getStorageClassSpecLoc(), 1667 diag::err_anonymous_union_with_storage_spec); 1668 Invalid = true; 1669 1670 // Recover by removing the storage specifier. 1671 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1672 PrevSpec, DiagID); 1673 } 1674 1675 // C++ [class.union]p2: 1676 // The member-specification of an anonymous union shall only 1677 // define non-static data members. [Note: nested types and 1678 // functions cannot be declared within an anonymous union. ] 1679 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1680 MemEnd = Record->decls_end(); 1681 Mem != MemEnd; ++Mem) { 1682 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1683 // C++ [class.union]p3: 1684 // An anonymous union shall not have private or protected 1685 // members (clause 11). 1686 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1687 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1688 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1689 Invalid = true; 1690 } 1691 } else if ((*Mem)->isImplicit()) { 1692 // Any implicit members are fine. 1693 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1694 // This is a type that showed up in an 1695 // elaborated-type-specifier inside the anonymous struct or 1696 // union, but which actually declares a type outside of the 1697 // anonymous struct or union. It's okay. 1698 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1699 if (!MemRecord->isAnonymousStructOrUnion() && 1700 MemRecord->getDeclName()) { 1701 // This is a nested type declaration. 1702 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1703 << (int)Record->isUnion(); 1704 Invalid = true; 1705 } 1706 } else { 1707 // We have something that isn't a non-static data 1708 // member. Complain about it. 1709 unsigned DK = diag::err_anonymous_record_bad_member; 1710 if (isa<TypeDecl>(*Mem)) 1711 DK = diag::err_anonymous_record_with_type; 1712 else if (isa<FunctionDecl>(*Mem)) 1713 DK = diag::err_anonymous_record_with_function; 1714 else if (isa<VarDecl>(*Mem)) 1715 DK = diag::err_anonymous_record_with_static; 1716 Diag((*Mem)->getLocation(), DK) 1717 << (int)Record->isUnion(); 1718 Invalid = true; 1719 } 1720 } 1721 } 1722 1723 if (!Record->isUnion() && !Owner->isRecord()) { 1724 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1725 << (int)getLangOptions().CPlusPlus; 1726 Invalid = true; 1727 } 1728 1729 // Mock up a declarator. 1730 Declarator Dc(DS, Declarator::TypeNameContext); 1731 TypeSourceInfo *TInfo = 0; 1732 GetTypeForDeclarator(Dc, S, &TInfo); 1733 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1734 1735 // Create a declaration for this anonymous struct/union. 1736 NamedDecl *Anon = 0; 1737 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1738 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1739 /*IdentifierInfo=*/0, 1740 Context.getTypeDeclType(Record), 1741 TInfo, 1742 /*BitWidth=*/0, /*Mutable=*/false); 1743 Anon->setAccess(AS_public); 1744 if (getLangOptions().CPlusPlus) 1745 FieldCollector->Add(cast<FieldDecl>(Anon)); 1746 } else { 1747 VarDecl::StorageClass SC; 1748 switch (DS.getStorageClassSpec()) { 1749 default: assert(0 && "Unknown storage class!"); 1750 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1751 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1752 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1753 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1754 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1755 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1756 case DeclSpec::SCS_mutable: 1757 // mutable can only appear on non-static class members, so it's always 1758 // an error here 1759 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1760 Invalid = true; 1761 SC = VarDecl::None; 1762 break; 1763 } 1764 1765 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1766 /*IdentifierInfo=*/0, 1767 Context.getTypeDeclType(Record), 1768 TInfo, 1769 SC); 1770 } 1771 Anon->setImplicit(); 1772 1773 // Add the anonymous struct/union object to the current 1774 // context. We'll be referencing this object when we refer to one of 1775 // its members. 1776 Owner->addDecl(Anon); 1777 1778 // Inject the members of the anonymous struct/union into the owning 1779 // context and into the identifier resolver chain for name lookup 1780 // purposes. 1781 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1782 Invalid = true; 1783 1784 // Mark this as an anonymous struct/union type. Note that we do not 1785 // do this until after we have already checked and injected the 1786 // members of this anonymous struct/union type, because otherwise 1787 // the members could be injected twice: once by DeclContext when it 1788 // builds its lookup table, and once by 1789 // InjectAnonymousStructOrUnionMembers. 1790 Record->setAnonymousStructOrUnion(true); 1791 1792 if (Invalid) 1793 Anon->setInvalidDecl(); 1794 1795 return DeclPtrTy::make(Anon); 1796} 1797 1798 1799/// GetNameForDeclarator - Determine the full declaration name for the 1800/// given Declarator. 1801DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1802 return GetNameFromUnqualifiedId(D.getName()); 1803} 1804 1805/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1806DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1807 switch (Name.getKind()) { 1808 case UnqualifiedId::IK_Identifier: 1809 return DeclarationName(Name.Identifier); 1810 1811 case UnqualifiedId::IK_OperatorFunctionId: 1812 return Context.DeclarationNames.getCXXOperatorName( 1813 Name.OperatorFunctionId.Operator); 1814 1815 case UnqualifiedId::IK_LiteralOperatorId: 1816 return Context.DeclarationNames.getCXXLiteralOperatorName( 1817 Name.Identifier); 1818 1819 case UnqualifiedId::IK_ConversionFunctionId: { 1820 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1821 if (Ty.isNull()) 1822 return DeclarationName(); 1823 1824 return Context.DeclarationNames.getCXXConversionFunctionName( 1825 Context.getCanonicalType(Ty)); 1826 } 1827 1828 case UnqualifiedId::IK_ConstructorName: { 1829 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1830 if (Ty.isNull()) 1831 return DeclarationName(); 1832 1833 return Context.DeclarationNames.getCXXConstructorName( 1834 Context.getCanonicalType(Ty)); 1835 } 1836 1837 case UnqualifiedId::IK_DestructorName: { 1838 QualType Ty = GetTypeFromParser(Name.DestructorName); 1839 if (Ty.isNull()) 1840 return DeclarationName(); 1841 1842 return Context.DeclarationNames.getCXXDestructorName( 1843 Context.getCanonicalType(Ty)); 1844 } 1845 1846 case UnqualifiedId::IK_TemplateId: { 1847 TemplateName TName 1848 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1849 return Context.getNameForTemplate(TName); 1850 } 1851 } 1852 1853 assert(false && "Unknown name kind"); 1854 return DeclarationName(); 1855} 1856 1857/// isNearlyMatchingFunction - Determine whether the C++ functions 1858/// Declaration and Definition are "nearly" matching. This heuristic 1859/// is used to improve diagnostics in the case where an out-of-line 1860/// function definition doesn't match any declaration within 1861/// the class or namespace. 1862static bool isNearlyMatchingFunction(ASTContext &Context, 1863 FunctionDecl *Declaration, 1864 FunctionDecl *Definition) { 1865 if (Declaration->param_size() != Definition->param_size()) 1866 return false; 1867 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1868 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1869 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1870 1871 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1872 DefParamTy.getNonReferenceType())) 1873 return false; 1874 } 1875 1876 return true; 1877} 1878 1879Sema::DeclPtrTy 1880Sema::HandleDeclarator(Scope *S, Declarator &D, 1881 MultiTemplateParamsArg TemplateParamLists, 1882 bool IsFunctionDefinition) { 1883 DeclarationName Name = GetNameForDeclarator(D); 1884 1885 // All of these full declarators require an identifier. If it doesn't have 1886 // one, the ParsedFreeStandingDeclSpec action should be used. 1887 if (!Name) { 1888 if (!D.isInvalidType()) // Reject this if we think it is valid. 1889 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1890 diag::err_declarator_need_ident) 1891 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1892 return DeclPtrTy(); 1893 } 1894 1895 // The scope passed in may not be a decl scope. Zip up the scope tree until 1896 // we find one that is. 1897 while ((S->getFlags() & Scope::DeclScope) == 0 || 1898 (S->getFlags() & Scope::TemplateParamScope) != 0) 1899 S = S->getParent(); 1900 1901 // If this is an out-of-line definition of a member of a class template 1902 // or class template partial specialization, we may need to rebuild the 1903 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1904 // for more information. 1905 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1906 // handle expressions properly. 1907 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1908 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1909 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1910 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1911 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1912 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1913 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1914 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1915 // FIXME: Preserve type source info. 1916 QualType T = GetTypeFromParser(DS.getTypeRep()); 1917 1918 DeclContext *SavedContext = CurContext; 1919 CurContext = DC; 1920 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1921 CurContext = SavedContext; 1922 1923 if (T.isNull()) 1924 return DeclPtrTy(); 1925 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1926 } 1927 } 1928 1929 DeclContext *DC; 1930 NamedDecl *New; 1931 1932 TypeSourceInfo *TInfo = 0; 1933 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1934 1935 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1936 ForRedeclaration); 1937 1938 // See if this is a redefinition of a variable in the same scope. 1939 if (D.getCXXScopeSpec().isInvalid()) { 1940 DC = CurContext; 1941 D.setInvalidType(); 1942 } else if (!D.getCXXScopeSpec().isSet()) { 1943 bool IsLinkageLookup = false; 1944 1945 // If the declaration we're planning to build will be a function 1946 // or object with linkage, then look for another declaration with 1947 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1948 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1949 /* Do nothing*/; 1950 else if (R->isFunctionType()) { 1951 if (CurContext->isFunctionOrMethod() || 1952 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1953 IsLinkageLookup = true; 1954 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1955 IsLinkageLookup = true; 1956 else if (CurContext->getLookupContext()->isTranslationUnit() && 1957 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1958 IsLinkageLookup = true; 1959 1960 if (IsLinkageLookup) 1961 Previous.clear(LookupRedeclarationWithLinkage); 1962 1963 DC = CurContext; 1964 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1965 } else { // Something like "int foo::x;" 1966 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1967 1968 if (!DC) { 1969 // If we could not compute the declaration context, it's because the 1970 // declaration context is dependent but does not refer to a class, 1971 // class template, or class template partial specialization. Complain 1972 // and return early, to avoid the coming semantic disaster. 1973 Diag(D.getIdentifierLoc(), 1974 diag::err_template_qualified_declarator_no_match) 1975 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1976 << D.getCXXScopeSpec().getRange(); 1977 return DeclPtrTy(); 1978 } 1979 1980 if (!DC->isDependentContext() && 1981 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1982 return DeclPtrTy(); 1983 1984 LookupQualifiedName(Previous, DC); 1985 1986 // Don't consider using declarations as previous declarations for 1987 // out-of-line members. 1988 RemoveUsingDecls(Previous); 1989 1990 // C++ 7.3.1.2p2: 1991 // Members (including explicit specializations of templates) of a named 1992 // namespace can also be defined outside that namespace by explicit 1993 // qualification of the name being defined, provided that the entity being 1994 // defined was already declared in the namespace and the definition appears 1995 // after the point of declaration in a namespace that encloses the 1996 // declarations namespace. 1997 // 1998 // Note that we only check the context at this point. We don't yet 1999 // have enough information to make sure that PrevDecl is actually 2000 // the declaration we want to match. For example, given: 2001 // 2002 // class X { 2003 // void f(); 2004 // void f(float); 2005 // }; 2006 // 2007 // void X::f(int) { } // ill-formed 2008 // 2009 // In this case, PrevDecl will point to the overload set 2010 // containing the two f's declared in X, but neither of them 2011 // matches. 2012 2013 // First check whether we named the global scope. 2014 if (isa<TranslationUnitDecl>(DC)) { 2015 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2016 << Name << D.getCXXScopeSpec().getRange(); 2017 } else { 2018 DeclContext *Cur = CurContext; 2019 while (isa<LinkageSpecDecl>(Cur)) 2020 Cur = Cur->getParent(); 2021 if (!Cur->Encloses(DC)) { 2022 // The qualifying scope doesn't enclose the original declaration. 2023 // Emit diagnostic based on current scope. 2024 SourceLocation L = D.getIdentifierLoc(); 2025 SourceRange R = D.getCXXScopeSpec().getRange(); 2026 if (isa<FunctionDecl>(Cur)) 2027 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2028 else 2029 Diag(L, diag::err_invalid_declarator_scope) 2030 << Name << cast<NamedDecl>(DC) << R; 2031 D.setInvalidType(); 2032 } 2033 } 2034 } 2035 2036 if (Previous.isSingleResult() && 2037 Previous.getFoundDecl()->isTemplateParameter()) { 2038 // Maybe we will complain about the shadowed template parameter. 2039 if (!D.isInvalidType()) 2040 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2041 Previous.getFoundDecl())) 2042 D.setInvalidType(); 2043 2044 // Just pretend that we didn't see the previous declaration. 2045 Previous.clear(); 2046 } 2047 2048 // In C++, the previous declaration we find might be a tag type 2049 // (class or enum). In this case, the new declaration will hide the 2050 // tag type. Note that this does does not apply if we're declaring a 2051 // typedef (C++ [dcl.typedef]p4). 2052 if (Previous.isSingleTagDecl() && 2053 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2054 Previous.clear(); 2055 2056 bool Redeclaration = false; 2057 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2058 if (TemplateParamLists.size()) { 2059 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2060 return DeclPtrTy(); 2061 } 2062 2063 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2064 } else if (R->isFunctionType()) { 2065 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2066 move(TemplateParamLists), 2067 IsFunctionDefinition, Redeclaration); 2068 } else { 2069 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2070 move(TemplateParamLists), 2071 Redeclaration); 2072 } 2073 2074 if (New == 0) 2075 return DeclPtrTy(); 2076 2077 // If this has an identifier and is not an invalid redeclaration or 2078 // function template specialization, add it to the scope stack. 2079 if (Name && !(Redeclaration && New->isInvalidDecl())) 2080 PushOnScopeChains(New, S); 2081 2082 return DeclPtrTy::make(New); 2083} 2084 2085/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2086/// types into constant array types in certain situations which would otherwise 2087/// be errors (for GCC compatibility). 2088static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2089 ASTContext &Context, 2090 bool &SizeIsNegative) { 2091 // This method tries to turn a variable array into a constant 2092 // array even when the size isn't an ICE. This is necessary 2093 // for compatibility with code that depends on gcc's buggy 2094 // constant expression folding, like struct {char x[(int)(char*)2];} 2095 SizeIsNegative = false; 2096 2097 QualifierCollector Qs; 2098 const Type *Ty = Qs.strip(T); 2099 2100 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2101 QualType Pointee = PTy->getPointeeType(); 2102 QualType FixedType = 2103 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2104 if (FixedType.isNull()) return FixedType; 2105 FixedType = Context.getPointerType(FixedType); 2106 return Qs.apply(FixedType); 2107 } 2108 2109 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2110 if (!VLATy) 2111 return QualType(); 2112 // FIXME: We should probably handle this case 2113 if (VLATy->getElementType()->isVariablyModifiedType()) 2114 return QualType(); 2115 2116 Expr::EvalResult EvalResult; 2117 if (!VLATy->getSizeExpr() || 2118 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2119 !EvalResult.Val.isInt()) 2120 return QualType(); 2121 2122 llvm::APSInt &Res = EvalResult.Val.getInt(); 2123 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2124 // TODO: preserve the size expression in declarator info 2125 return Context.getConstantArrayType(VLATy->getElementType(), 2126 Res, ArrayType::Normal, 0); 2127 } 2128 2129 SizeIsNegative = true; 2130 return QualType(); 2131} 2132 2133/// \brief Register the given locally-scoped external C declaration so 2134/// that it can be found later for redeclarations 2135void 2136Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2137 const LookupResult &Previous, 2138 Scope *S) { 2139 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2140 "Decl is not a locally-scoped decl!"); 2141 // Note that we have a locally-scoped external with this name. 2142 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2143 2144 if (!Previous.isSingleResult()) 2145 return; 2146 2147 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2148 2149 // If there was a previous declaration of this variable, it may be 2150 // in our identifier chain. Update the identifier chain with the new 2151 // declaration. 2152 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2153 // The previous declaration was found on the identifer resolver 2154 // chain, so remove it from its scope. 2155 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2156 S = S->getParent(); 2157 2158 if (S) 2159 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2160 } 2161} 2162 2163/// \brief Diagnose function specifiers on a declaration of an identifier that 2164/// does not identify a function. 2165void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2166 // FIXME: We should probably indicate the identifier in question to avoid 2167 // confusion for constructs like "inline int a(), b;" 2168 if (D.getDeclSpec().isInlineSpecified()) 2169 Diag(D.getDeclSpec().getInlineSpecLoc(), 2170 diag::err_inline_non_function); 2171 2172 if (D.getDeclSpec().isVirtualSpecified()) 2173 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2174 diag::err_virtual_non_function); 2175 2176 if (D.getDeclSpec().isExplicitSpecified()) 2177 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2178 diag::err_explicit_non_function); 2179} 2180 2181NamedDecl* 2182Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2183 QualType R, TypeSourceInfo *TInfo, 2184 LookupResult &Previous, bool &Redeclaration) { 2185 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2186 if (D.getCXXScopeSpec().isSet()) { 2187 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2188 << D.getCXXScopeSpec().getRange(); 2189 D.setInvalidType(); 2190 // Pretend we didn't see the scope specifier. 2191 DC = 0; 2192 } 2193 2194 if (getLangOptions().CPlusPlus) { 2195 // Check that there are no default arguments (C++ only). 2196 CheckExtraCXXDefaultArguments(D); 2197 } 2198 2199 DiagnoseFunctionSpecifiers(D); 2200 2201 if (D.getDeclSpec().isThreadSpecified()) 2202 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2203 2204 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2205 if (!NewTD) return 0; 2206 2207 // Handle attributes prior to checking for duplicates in MergeVarDecl 2208 ProcessDeclAttributes(S, NewTD, D); 2209 2210 // Merge the decl with the existing one if appropriate. If the decl is 2211 // in an outer scope, it isn't the same thing. 2212 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2213 if (!Previous.empty()) { 2214 Redeclaration = true; 2215 MergeTypeDefDecl(NewTD, Previous); 2216 } 2217 2218 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2219 // then it shall have block scope. 2220 QualType T = NewTD->getUnderlyingType(); 2221 if (T->isVariablyModifiedType()) { 2222 CurFunctionNeedsScopeChecking = true; 2223 2224 if (S->getFnParent() == 0) { 2225 bool SizeIsNegative; 2226 QualType FixedTy = 2227 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2228 if (!FixedTy.isNull()) { 2229 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2230 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2231 } else { 2232 if (SizeIsNegative) 2233 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2234 else if (T->isVariableArrayType()) 2235 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2236 else 2237 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2238 NewTD->setInvalidDecl(); 2239 } 2240 } 2241 } 2242 2243 // If this is the C FILE type, notify the AST context. 2244 if (IdentifierInfo *II = NewTD->getIdentifier()) 2245 if (!NewTD->isInvalidDecl() && 2246 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2247 if (II->isStr("FILE")) 2248 Context.setFILEDecl(NewTD); 2249 else if (II->isStr("jmp_buf")) 2250 Context.setjmp_bufDecl(NewTD); 2251 else if (II->isStr("sigjmp_buf")) 2252 Context.setsigjmp_bufDecl(NewTD); 2253 } 2254 2255 return NewTD; 2256} 2257 2258/// \brief Determines whether the given declaration is an out-of-scope 2259/// previous declaration. 2260/// 2261/// This routine should be invoked when name lookup has found a 2262/// previous declaration (PrevDecl) that is not in the scope where a 2263/// new declaration by the same name is being introduced. If the new 2264/// declaration occurs in a local scope, previous declarations with 2265/// linkage may still be considered previous declarations (C99 2266/// 6.2.2p4-5, C++ [basic.link]p6). 2267/// 2268/// \param PrevDecl the previous declaration found by name 2269/// lookup 2270/// 2271/// \param DC the context in which the new declaration is being 2272/// declared. 2273/// 2274/// \returns true if PrevDecl is an out-of-scope previous declaration 2275/// for a new delcaration with the same name. 2276static bool 2277isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2278 ASTContext &Context) { 2279 if (!PrevDecl) 2280 return 0; 2281 2282 if (!PrevDecl->hasLinkage()) 2283 return false; 2284 2285 if (Context.getLangOptions().CPlusPlus) { 2286 // C++ [basic.link]p6: 2287 // If there is a visible declaration of an entity with linkage 2288 // having the same name and type, ignoring entities declared 2289 // outside the innermost enclosing namespace scope, the block 2290 // scope declaration declares that same entity and receives the 2291 // linkage of the previous declaration. 2292 DeclContext *OuterContext = DC->getLookupContext(); 2293 if (!OuterContext->isFunctionOrMethod()) 2294 // This rule only applies to block-scope declarations. 2295 return false; 2296 else { 2297 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2298 if (PrevOuterContext->isRecord()) 2299 // We found a member function: ignore it. 2300 return false; 2301 else { 2302 // Find the innermost enclosing namespace for the new and 2303 // previous declarations. 2304 while (!OuterContext->isFileContext()) 2305 OuterContext = OuterContext->getParent(); 2306 while (!PrevOuterContext->isFileContext()) 2307 PrevOuterContext = PrevOuterContext->getParent(); 2308 2309 // The previous declaration is in a different namespace, so it 2310 // isn't the same function. 2311 if (OuterContext->getPrimaryContext() != 2312 PrevOuterContext->getPrimaryContext()) 2313 return false; 2314 } 2315 } 2316 } 2317 2318 return true; 2319} 2320 2321NamedDecl* 2322Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2323 QualType R, TypeSourceInfo *TInfo, 2324 LookupResult &Previous, 2325 MultiTemplateParamsArg TemplateParamLists, 2326 bool &Redeclaration) { 2327 DeclarationName Name = GetNameForDeclarator(D); 2328 2329 // Check that there are no default arguments (C++ only). 2330 if (getLangOptions().CPlusPlus) 2331 CheckExtraCXXDefaultArguments(D); 2332 2333 VarDecl *NewVD; 2334 VarDecl::StorageClass SC; 2335 switch (D.getDeclSpec().getStorageClassSpec()) { 2336 default: assert(0 && "Unknown storage class!"); 2337 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2338 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2339 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2340 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2341 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2342 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2343 case DeclSpec::SCS_mutable: 2344 // mutable can only appear on non-static class members, so it's always 2345 // an error here 2346 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2347 D.setInvalidType(); 2348 SC = VarDecl::None; 2349 break; 2350 } 2351 2352 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2353 if (!II) { 2354 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2355 << Name.getAsString(); 2356 return 0; 2357 } 2358 2359 DiagnoseFunctionSpecifiers(D); 2360 2361 if (!DC->isRecord() && S->getFnParent() == 0) { 2362 // C99 6.9p2: The storage-class specifiers auto and register shall not 2363 // appear in the declaration specifiers in an external declaration. 2364 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2365 2366 // If this is a register variable with an asm label specified, then this 2367 // is a GNU extension. 2368 if (SC == VarDecl::Register && D.getAsmLabel()) 2369 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2370 else 2371 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2372 D.setInvalidType(); 2373 } 2374 } 2375 if (DC->isRecord() && !CurContext->isRecord()) { 2376 // This is an out-of-line definition of a static data member. 2377 if (SC == VarDecl::Static) { 2378 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2379 diag::err_static_out_of_line) 2380 << CodeModificationHint::CreateRemoval( 2381 D.getDeclSpec().getStorageClassSpecLoc()); 2382 } else if (SC == VarDecl::None) 2383 SC = VarDecl::Static; 2384 } 2385 if (SC == VarDecl::Static) { 2386 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2387 if (RD->isLocalClass()) 2388 Diag(D.getIdentifierLoc(), 2389 diag::err_static_data_member_not_allowed_in_local_class) 2390 << Name << RD->getDeclName(); 2391 } 2392 } 2393 2394 // Match up the template parameter lists with the scope specifier, then 2395 // determine whether we have a template or a template specialization. 2396 bool isExplicitSpecialization = false; 2397 if (TemplateParameterList *TemplateParams 2398 = MatchTemplateParametersToScopeSpecifier( 2399 D.getDeclSpec().getSourceRange().getBegin(), 2400 D.getCXXScopeSpec(), 2401 (TemplateParameterList**)TemplateParamLists.get(), 2402 TemplateParamLists.size(), 2403 isExplicitSpecialization)) { 2404 if (TemplateParams->size() > 0) { 2405 // There is no such thing as a variable template. 2406 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2407 << II 2408 << SourceRange(TemplateParams->getTemplateLoc(), 2409 TemplateParams->getRAngleLoc()); 2410 return 0; 2411 } else { 2412 // There is an extraneous 'template<>' for this variable. Complain 2413 // about it, but allow the declaration of the variable. 2414 Diag(TemplateParams->getTemplateLoc(), 2415 diag::err_template_variable_noparams) 2416 << II 2417 << SourceRange(TemplateParams->getTemplateLoc(), 2418 TemplateParams->getRAngleLoc()); 2419 2420 isExplicitSpecialization = true; 2421 } 2422 } 2423 2424 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2425 II, R, TInfo, SC); 2426 2427 if (D.isInvalidType()) 2428 NewVD->setInvalidDecl(); 2429 2430 if (D.getDeclSpec().isThreadSpecified()) { 2431 if (NewVD->hasLocalStorage()) 2432 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2433 else if (!Context.Target.isTLSSupported()) 2434 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2435 else 2436 NewVD->setThreadSpecified(true); 2437 } 2438 2439 // Set the lexical context. If the declarator has a C++ scope specifier, the 2440 // lexical context will be different from the semantic context. 2441 NewVD->setLexicalDeclContext(CurContext); 2442 2443 // Handle attributes prior to checking for duplicates in MergeVarDecl 2444 ProcessDeclAttributes(S, NewVD, D); 2445 2446 // Handle GNU asm-label extension (encoded as an attribute). 2447 if (Expr *E = (Expr*) D.getAsmLabel()) { 2448 // The parser guarantees this is a string. 2449 StringLiteral *SE = cast<StringLiteral>(E); 2450 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2451 } 2452 2453 // Don't consider existing declarations that are in a different 2454 // scope and are out-of-semantic-context declarations (if the new 2455 // declaration has linkage). 2456 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2457 2458 // Merge the decl with the existing one if appropriate. 2459 if (!Previous.empty()) { 2460 if (Previous.isSingleResult() && 2461 isa<FieldDecl>(Previous.getFoundDecl()) && 2462 D.getCXXScopeSpec().isSet()) { 2463 // The user tried to define a non-static data member 2464 // out-of-line (C++ [dcl.meaning]p1). 2465 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2466 << D.getCXXScopeSpec().getRange(); 2467 Previous.clear(); 2468 NewVD->setInvalidDecl(); 2469 } 2470 } else if (D.getCXXScopeSpec().isSet()) { 2471 // No previous declaration in the qualifying scope. 2472 Diag(D.getIdentifierLoc(), diag::err_no_member) 2473 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2474 << D.getCXXScopeSpec().getRange(); 2475 NewVD->setInvalidDecl(); 2476 } 2477 2478 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2479 2480 // This is an explicit specialization of a static data member. Check it. 2481 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2482 CheckMemberSpecialization(NewVD, Previous)) 2483 NewVD->setInvalidDecl(); 2484 2485 // attributes declared post-definition are currently ignored 2486 if (Previous.isSingleResult()) { 2487 const VarDecl *Def = 0; 2488 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2489 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2490 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2491 Diag(Def->getLocation(), diag::note_previous_definition); 2492 } 2493 } 2494 2495 // If this is a locally-scoped extern C variable, update the map of 2496 // such variables. 2497 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2498 !NewVD->isInvalidDecl()) 2499 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2500 2501 return NewVD; 2502} 2503 2504/// \brief Perform semantic checking on a newly-created variable 2505/// declaration. 2506/// 2507/// This routine performs all of the type-checking required for a 2508/// variable declaration once it has been built. It is used both to 2509/// check variables after they have been parsed and their declarators 2510/// have been translated into a declaration, and to check variables 2511/// that have been instantiated from a template. 2512/// 2513/// Sets NewVD->isInvalidDecl() if an error was encountered. 2514void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2515 LookupResult &Previous, 2516 bool &Redeclaration) { 2517 // If the decl is already known invalid, don't check it. 2518 if (NewVD->isInvalidDecl()) 2519 return; 2520 2521 QualType T = NewVD->getType(); 2522 2523 if (T->isObjCInterfaceType()) { 2524 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2525 return NewVD->setInvalidDecl(); 2526 } 2527 2528 // Emit an error if an address space was applied to decl with local storage. 2529 // This includes arrays of objects with address space qualifiers, but not 2530 // automatic variables that point to other address spaces. 2531 // ISO/IEC TR 18037 S5.1.2 2532 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2533 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2534 return NewVD->setInvalidDecl(); 2535 } 2536 2537 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2538 && !NewVD->hasAttr<BlocksAttr>()) 2539 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2540 2541 bool isVM = T->isVariablyModifiedType(); 2542 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2543 NewVD->hasAttr<BlocksAttr>()) 2544 CurFunctionNeedsScopeChecking = true; 2545 2546 if ((isVM && NewVD->hasLinkage()) || 2547 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2548 bool SizeIsNegative; 2549 QualType FixedTy = 2550 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2551 2552 if (FixedTy.isNull() && T->isVariableArrayType()) { 2553 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2554 // FIXME: This won't give the correct result for 2555 // int a[10][n]; 2556 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2557 2558 if (NewVD->isFileVarDecl()) 2559 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2560 << SizeRange; 2561 else if (NewVD->getStorageClass() == VarDecl::Static) 2562 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2563 << SizeRange; 2564 else 2565 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2566 << SizeRange; 2567 return NewVD->setInvalidDecl(); 2568 } 2569 2570 if (FixedTy.isNull()) { 2571 if (NewVD->isFileVarDecl()) 2572 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2573 else 2574 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2575 return NewVD->setInvalidDecl(); 2576 } 2577 2578 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2579 NewVD->setType(FixedTy); 2580 } 2581 2582 if (Previous.empty() && NewVD->isExternC()) { 2583 // Since we did not find anything by this name and we're declaring 2584 // an extern "C" variable, look for a non-visible extern "C" 2585 // declaration with the same name. 2586 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2587 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2588 if (Pos != LocallyScopedExternalDecls.end()) 2589 Previous.addDecl(Pos->second); 2590 } 2591 2592 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2593 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2594 << T; 2595 return NewVD->setInvalidDecl(); 2596 } 2597 2598 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2599 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2600 return NewVD->setInvalidDecl(); 2601 } 2602 2603 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2604 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2605 return NewVD->setInvalidDecl(); 2606 } 2607 2608 if (!Previous.empty()) { 2609 Redeclaration = true; 2610 MergeVarDecl(NewVD, Previous); 2611 } 2612} 2613 2614/// \brief Data used with FindOverriddenMethod 2615struct FindOverriddenMethodData { 2616 Sema *S; 2617 CXXMethodDecl *Method; 2618}; 2619 2620/// \brief Member lookup function that determines whether a given C++ 2621/// method overrides a method in a base class, to be used with 2622/// CXXRecordDecl::lookupInBases(). 2623static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2624 CXXBasePath &Path, 2625 void *UserData) { 2626 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2627 2628 FindOverriddenMethodData *Data 2629 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2630 2631 DeclarationName Name = Data->Method->getDeclName(); 2632 2633 // FIXME: Do we care about other names here too? 2634 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2635 // We really want to find the base class constructor here. 2636 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2637 CanQualType CT = Data->S->Context.getCanonicalType(T); 2638 2639 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2640 } 2641 2642 for (Path.Decls = BaseRecord->lookup(Name); 2643 Path.Decls.first != Path.Decls.second; 2644 ++Path.Decls.first) { 2645 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2646 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2647 return true; 2648 } 2649 } 2650 2651 return false; 2652} 2653 2654/// AddOverriddenMethods - See if a method overrides any in the base classes, 2655/// and if so, check that it's a valid override and remember it. 2656void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2657 // Look for virtual methods in base classes that this method might override. 2658 CXXBasePaths Paths; 2659 FindOverriddenMethodData Data; 2660 Data.Method = MD; 2661 Data.S = this; 2662 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2663 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2664 E = Paths.found_decls_end(); I != E; ++I) { 2665 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2666 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2667 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2668 !CheckOverridingFunctionAttributes(MD, OldMD)) 2669 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2670 } 2671 } 2672 } 2673} 2674 2675NamedDecl* 2676Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2677 QualType R, TypeSourceInfo *TInfo, 2678 LookupResult &Previous, 2679 MultiTemplateParamsArg TemplateParamLists, 2680 bool IsFunctionDefinition, bool &Redeclaration) { 2681 assert(R.getTypePtr()->isFunctionType()); 2682 2683 DeclarationName Name = GetNameForDeclarator(D); 2684 FunctionDecl::StorageClass SC = FunctionDecl::None; 2685 switch (D.getDeclSpec().getStorageClassSpec()) { 2686 default: assert(0 && "Unknown storage class!"); 2687 case DeclSpec::SCS_auto: 2688 case DeclSpec::SCS_register: 2689 case DeclSpec::SCS_mutable: 2690 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2691 diag::err_typecheck_sclass_func); 2692 D.setInvalidType(); 2693 break; 2694 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2695 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2696 case DeclSpec::SCS_static: { 2697 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2698 // C99 6.7.1p5: 2699 // The declaration of an identifier for a function that has 2700 // block scope shall have no explicit storage-class specifier 2701 // other than extern 2702 // See also (C++ [dcl.stc]p4). 2703 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2704 diag::err_static_block_func); 2705 SC = FunctionDecl::None; 2706 } else 2707 SC = FunctionDecl::Static; 2708 break; 2709 } 2710 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2711 } 2712 2713 if (D.getDeclSpec().isThreadSpecified()) 2714 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2715 2716 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2717 bool isInline = D.getDeclSpec().isInlineSpecified(); 2718 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2719 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2720 2721 // Check that the return type is not an abstract class type. 2722 // For record types, this is done by the AbstractClassUsageDiagnoser once 2723 // the class has been completely parsed. 2724 if (!DC->isRecord() && 2725 RequireNonAbstractType(D.getIdentifierLoc(), 2726 R->getAs<FunctionType>()->getResultType(), 2727 diag::err_abstract_type_in_decl, 2728 AbstractReturnType)) 2729 D.setInvalidType(); 2730 2731 // Do not allow returning a objc interface by-value. 2732 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2733 Diag(D.getIdentifierLoc(), 2734 diag::err_object_cannot_be_passed_returned_by_value) << 0 2735 << R->getAs<FunctionType>()->getResultType(); 2736 D.setInvalidType(); 2737 } 2738 2739 bool isVirtualOkay = false; 2740 FunctionDecl *NewFD; 2741 2742 if (isFriend) { 2743 // C++ [class.friend]p5 2744 // A function can be defined in a friend declaration of a 2745 // class . . . . Such a function is implicitly inline. 2746 isInline |= IsFunctionDefinition; 2747 } 2748 2749 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2750 // This is a C++ constructor declaration. 2751 assert(DC->isRecord() && 2752 "Constructors can only be declared in a member context"); 2753 2754 R = CheckConstructorDeclarator(D, R, SC); 2755 2756 // Create the new declaration 2757 NewFD = CXXConstructorDecl::Create(Context, 2758 cast<CXXRecordDecl>(DC), 2759 D.getIdentifierLoc(), Name, R, TInfo, 2760 isExplicit, isInline, 2761 /*isImplicitlyDeclared=*/false); 2762 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2763 // This is a C++ destructor declaration. 2764 if (DC->isRecord()) { 2765 R = CheckDestructorDeclarator(D, SC); 2766 2767 NewFD = CXXDestructorDecl::Create(Context, 2768 cast<CXXRecordDecl>(DC), 2769 D.getIdentifierLoc(), Name, R, 2770 isInline, 2771 /*isImplicitlyDeclared=*/false); 2772 2773 isVirtualOkay = true; 2774 } else { 2775 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2776 2777 // Create a FunctionDecl to satisfy the function definition parsing 2778 // code path. 2779 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2780 Name, R, TInfo, SC, isInline, 2781 /*hasPrototype=*/true); 2782 D.setInvalidType(); 2783 } 2784 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2785 if (!DC->isRecord()) { 2786 Diag(D.getIdentifierLoc(), 2787 diag::err_conv_function_not_member); 2788 return 0; 2789 } 2790 2791 CheckConversionDeclarator(D, R, SC); 2792 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2793 D.getIdentifierLoc(), Name, R, TInfo, 2794 isInline, isExplicit); 2795 2796 isVirtualOkay = true; 2797 } else if (DC->isRecord()) { 2798 // If the of the function is the same as the name of the record, then this 2799 // must be an invalid constructor that has a return type. 2800 // (The parser checks for a return type and makes the declarator a 2801 // constructor if it has no return type). 2802 // must have an invalid constructor that has a return type 2803 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2804 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2805 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2806 << SourceRange(D.getIdentifierLoc()); 2807 return 0; 2808 } 2809 2810 bool isStatic = SC == FunctionDecl::Static; 2811 2812 // [class.free]p1: 2813 // Any allocation function for a class T is a static member 2814 // (even if not explicitly declared static). 2815 if (Name.getCXXOverloadedOperator() == OO_New || 2816 Name.getCXXOverloadedOperator() == OO_Array_New) 2817 isStatic = true; 2818 2819 // [class.free]p6 Any deallocation function for a class X is a static member 2820 // (even if not explicitly declared static). 2821 if (Name.getCXXOverloadedOperator() == OO_Delete || 2822 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2823 isStatic = true; 2824 2825 // This is a C++ method declaration. 2826 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2827 D.getIdentifierLoc(), Name, R, TInfo, 2828 isStatic, isInline); 2829 2830 isVirtualOkay = !isStatic; 2831 } else { 2832 // Determine whether the function was written with a 2833 // prototype. This true when: 2834 // - we're in C++ (where every function has a prototype), 2835 // - there is a prototype in the declarator, or 2836 // - the type R of the function is some kind of typedef or other reference 2837 // to a type name (which eventually refers to a function type). 2838 bool HasPrototype = 2839 getLangOptions().CPlusPlus || 2840 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2841 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2842 2843 NewFD = FunctionDecl::Create(Context, DC, 2844 D.getIdentifierLoc(), 2845 Name, R, TInfo, SC, isInline, HasPrototype); 2846 } 2847 2848 if (D.isInvalidType()) 2849 NewFD->setInvalidDecl(); 2850 2851 // Set the lexical context. If the declarator has a C++ 2852 // scope specifier, or is the object of a friend declaration, the 2853 // lexical context will be different from the semantic context. 2854 NewFD->setLexicalDeclContext(CurContext); 2855 2856 // Match up the template parameter lists with the scope specifier, then 2857 // determine whether we have a template or a template specialization. 2858 FunctionTemplateDecl *FunctionTemplate = 0; 2859 bool isExplicitSpecialization = false; 2860 bool isFunctionTemplateSpecialization = false; 2861 if (TemplateParameterList *TemplateParams 2862 = MatchTemplateParametersToScopeSpecifier( 2863 D.getDeclSpec().getSourceRange().getBegin(), 2864 D.getCXXScopeSpec(), 2865 (TemplateParameterList**)TemplateParamLists.get(), 2866 TemplateParamLists.size(), 2867 isExplicitSpecialization)) { 2868 if (TemplateParams->size() > 0) { 2869 // This is a function template 2870 2871 // Check that we can declare a template here. 2872 if (CheckTemplateDeclScope(S, TemplateParams)) 2873 return 0; 2874 2875 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2876 NewFD->getLocation(), 2877 Name, TemplateParams, 2878 NewFD); 2879 FunctionTemplate->setLexicalDeclContext(CurContext); 2880 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2881 } else { 2882 // This is a function template specialization. 2883 isFunctionTemplateSpecialization = true; 2884 } 2885 2886 // FIXME: Free this memory properly. 2887 TemplateParamLists.release(); 2888 } 2889 2890 // C++ [dcl.fct.spec]p5: 2891 // The virtual specifier shall only be used in declarations of 2892 // nonstatic class member functions that appear within a 2893 // member-specification of a class declaration; see 10.3. 2894 // 2895 if (isVirtual && !NewFD->isInvalidDecl()) { 2896 if (!isVirtualOkay) { 2897 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2898 diag::err_virtual_non_function); 2899 } else if (!CurContext->isRecord()) { 2900 // 'virtual' was specified outside of the class. 2901 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2902 << CodeModificationHint::CreateRemoval( 2903 D.getDeclSpec().getVirtualSpecLoc()); 2904 } else { 2905 // Okay: Add virtual to the method. 2906 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2907 CurClass->setMethodAsVirtual(NewFD); 2908 } 2909 } 2910 2911 // Filter out previous declarations that don't match the scope. 2912 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2913 2914 if (isFriend) { 2915 // DC is the namespace in which the function is being declared. 2916 assert((DC->isFileContext() || !Previous.empty()) && 2917 "previously-undeclared friend function being created " 2918 "in a non-namespace context"); 2919 2920 if (FunctionTemplate) { 2921 FunctionTemplate->setObjectOfFriendDecl( 2922 /* PreviouslyDeclared= */ !Previous.empty()); 2923 FunctionTemplate->setAccess(AS_public); 2924 } 2925 else 2926 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2927 2928 NewFD->setAccess(AS_public); 2929 } 2930 2931 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2932 !CurContext->isRecord()) { 2933 // C++ [class.static]p1: 2934 // A data or function member of a class may be declared static 2935 // in a class definition, in which case it is a static member of 2936 // the class. 2937 2938 // Complain about the 'static' specifier if it's on an out-of-line 2939 // member function definition. 2940 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2941 diag::err_static_out_of_line) 2942 << CodeModificationHint::CreateRemoval( 2943 D.getDeclSpec().getStorageClassSpecLoc()); 2944 } 2945 2946 // Handle GNU asm-label extension (encoded as an attribute). 2947 if (Expr *E = (Expr*) D.getAsmLabel()) { 2948 // The parser guarantees this is a string. 2949 StringLiteral *SE = cast<StringLiteral>(E); 2950 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2951 } 2952 2953 // Copy the parameter declarations from the declarator D to the function 2954 // declaration NewFD, if they are available. First scavenge them into Params. 2955 llvm::SmallVector<ParmVarDecl*, 16> Params; 2956 if (D.getNumTypeObjects() > 0) { 2957 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2958 2959 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2960 // function that takes no arguments, not a function that takes a 2961 // single void argument. 2962 // We let through "const void" here because Sema::GetTypeForDeclarator 2963 // already checks for that case. 2964 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2965 FTI.ArgInfo[0].Param && 2966 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2967 // Empty arg list, don't push any params. 2968 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2969 2970 // In C++, the empty parameter-type-list must be spelled "void"; a 2971 // typedef of void is not permitted. 2972 if (getLangOptions().CPlusPlus && 2973 Param->getType().getUnqualifiedType() != Context.VoidTy) 2974 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2975 // FIXME: Leaks decl? 2976 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2977 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2978 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2979 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2980 Param->setDeclContext(NewFD); 2981 Params.push_back(Param); 2982 } 2983 } 2984 2985 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2986 // When we're declaring a function with a typedef, typeof, etc as in the 2987 // following example, we'll need to synthesize (unnamed) 2988 // parameters for use in the declaration. 2989 // 2990 // @code 2991 // typedef void fn(int); 2992 // fn f; 2993 // @endcode 2994 2995 // Synthesize a parameter for each argument type. 2996 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2997 AE = FT->arg_type_end(); AI != AE; ++AI) { 2998 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2999 SourceLocation(), 0, 3000 *AI, /*TInfo=*/0, 3001 VarDecl::None, 0); 3002 Param->setImplicit(); 3003 Params.push_back(Param); 3004 } 3005 } else { 3006 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3007 "Should not need args for typedef of non-prototype fn"); 3008 } 3009 // Finally, we know we have the right number of parameters, install them. 3010 NewFD->setParams(Context, Params.data(), Params.size()); 3011 3012 // If the declarator is a template-id, translate the parser's template 3013 // argument list into our AST format. 3014 bool HasExplicitTemplateArgs = false; 3015 TemplateArgumentListInfo TemplateArgs; 3016 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3017 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3018 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3019 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3020 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3021 TemplateId->getTemplateArgs(), 3022 TemplateId->NumArgs); 3023 translateTemplateArguments(TemplateArgsPtr, 3024 TemplateArgs); 3025 TemplateArgsPtr.release(); 3026 3027 HasExplicitTemplateArgs = true; 3028 3029 if (FunctionTemplate) { 3030 // FIXME: Diagnose function template with explicit template 3031 // arguments. 3032 HasExplicitTemplateArgs = false; 3033 } else if (!isFunctionTemplateSpecialization && 3034 !D.getDeclSpec().isFriendSpecified()) { 3035 // We have encountered something that the user meant to be a 3036 // specialization (because it has explicitly-specified template 3037 // arguments) but that was not introduced with a "template<>" (or had 3038 // too few of them). 3039 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3040 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3041 << CodeModificationHint::CreateInsertion( 3042 D.getDeclSpec().getSourceRange().getBegin(), 3043 "template<> "); 3044 isFunctionTemplateSpecialization = true; 3045 } 3046 } 3047 3048 if (isFunctionTemplateSpecialization) { 3049 if (CheckFunctionTemplateSpecialization(NewFD, 3050 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3051 Previous)) 3052 NewFD->setInvalidDecl(); 3053 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3054 CheckMemberSpecialization(NewFD, Previous)) 3055 NewFD->setInvalidDecl(); 3056 3057 // Perform semantic checking on the function declaration. 3058 bool OverloadableAttrRequired = false; // FIXME: HACK! 3059 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3060 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3061 3062 assert((NewFD->isInvalidDecl() || !Redeclaration || 3063 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3064 "previous declaration set still overloaded"); 3065 3066 // If we have a function template, check the template parameter 3067 // list. This will check and merge default template arguments. 3068 if (FunctionTemplate) { 3069 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3070 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3071 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3072 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3073 : TPC_FunctionTemplate); 3074 } 3075 3076 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3077 // An out-of-line member function declaration must also be a 3078 // definition (C++ [dcl.meaning]p1). 3079 // Note that this is not the case for explicit specializations of 3080 // function templates or member functions of class templates, per 3081 // C++ [temp.expl.spec]p2. 3082 if (!IsFunctionDefinition && !isFriend && 3083 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3084 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3085 << D.getCXXScopeSpec().getRange(); 3086 NewFD->setInvalidDecl(); 3087 } else if (!Redeclaration) { 3088 // The user tried to provide an out-of-line definition for a 3089 // function that is a member of a class or namespace, but there 3090 // was no such member function declared (C++ [class.mfct]p2, 3091 // C++ [namespace.memdef]p2). For example: 3092 // 3093 // class X { 3094 // void f() const; 3095 // }; 3096 // 3097 // void X::f() { } // ill-formed 3098 // 3099 // Complain about this problem, and attempt to suggest close 3100 // matches (e.g., those that differ only in cv-qualifiers and 3101 // whether the parameter types are references). 3102 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3103 << Name << DC << D.getCXXScopeSpec().getRange(); 3104 NewFD->setInvalidDecl(); 3105 3106 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3107 ForRedeclaration); 3108 LookupQualifiedName(Prev, DC); 3109 assert(!Prev.isAmbiguous() && 3110 "Cannot have an ambiguity in previous-declaration lookup"); 3111 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3112 Func != FuncEnd; ++Func) { 3113 if (isa<FunctionDecl>(*Func) && 3114 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3115 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3116 } 3117 } 3118 } 3119 3120 // Handle attributes. We need to have merged decls when handling attributes 3121 // (for example to check for conflicts, etc). 3122 // FIXME: This needs to happen before we merge declarations. Then, 3123 // let attribute merging cope with attribute conflicts. 3124 ProcessDeclAttributes(S, NewFD, D); 3125 3126 // attributes declared post-definition are currently ignored 3127 if (Redeclaration && Previous.isSingleResult()) { 3128 const FunctionDecl *Def; 3129 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3130 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3131 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3132 Diag(Def->getLocation(), diag::note_previous_definition); 3133 } 3134 } 3135 3136 AddKnownFunctionAttributes(NewFD); 3137 3138 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3139 // If a function name is overloadable in C, then every function 3140 // with that name must be marked "overloadable". 3141 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3142 << Redeclaration << NewFD; 3143 if (!Previous.empty()) 3144 Diag(Previous.getRepresentativeDecl()->getLocation(), 3145 diag::note_attribute_overloadable_prev_overload); 3146 NewFD->addAttr(::new (Context) OverloadableAttr()); 3147 } 3148 3149 // If this is a locally-scoped extern C function, update the 3150 // map of such names. 3151 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3152 && !NewFD->isInvalidDecl()) 3153 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3154 3155 // Set this FunctionDecl's range up to the right paren. 3156 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3157 3158 if (FunctionTemplate && NewFD->isInvalidDecl()) 3159 FunctionTemplate->setInvalidDecl(); 3160 3161 if (FunctionTemplate) 3162 return FunctionTemplate; 3163 3164 return NewFD; 3165} 3166 3167/// \brief Perform semantic checking of a new function declaration. 3168/// 3169/// Performs semantic analysis of the new function declaration 3170/// NewFD. This routine performs all semantic checking that does not 3171/// require the actual declarator involved in the declaration, and is 3172/// used both for the declaration of functions as they are parsed 3173/// (called via ActOnDeclarator) and for the declaration of functions 3174/// that have been instantiated via C++ template instantiation (called 3175/// via InstantiateDecl). 3176/// 3177/// \param IsExplicitSpecialiation whether this new function declaration is 3178/// an explicit specialization of the previous declaration. 3179/// 3180/// This sets NewFD->isInvalidDecl() to true if there was an error. 3181void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3182 LookupResult &Previous, 3183 bool IsExplicitSpecialization, 3184 bool &Redeclaration, 3185 bool &OverloadableAttrRequired) { 3186 // If NewFD is already known erroneous, don't do any of this checking. 3187 if (NewFD->isInvalidDecl()) 3188 return; 3189 3190 if (NewFD->getResultType()->isVariablyModifiedType()) { 3191 // Functions returning a variably modified type violate C99 6.7.5.2p2 3192 // because all functions have linkage. 3193 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3194 return NewFD->setInvalidDecl(); 3195 } 3196 3197 if (NewFD->isMain()) 3198 CheckMain(NewFD); 3199 3200 // Check for a previous declaration of this name. 3201 if (Previous.empty() && NewFD->isExternC()) { 3202 // Since we did not find anything by this name and we're declaring 3203 // an extern "C" function, look for a non-visible extern "C" 3204 // declaration with the same name. 3205 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3206 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3207 if (Pos != LocallyScopedExternalDecls.end()) 3208 Previous.addDecl(Pos->second); 3209 } 3210 3211 // Merge or overload the declaration with an existing declaration of 3212 // the same name, if appropriate. 3213 if (!Previous.empty()) { 3214 // Determine whether NewFD is an overload of PrevDecl or 3215 // a declaration that requires merging. If it's an overload, 3216 // there's no more work to do here; we'll just add the new 3217 // function to the scope. 3218 3219 NamedDecl *OldDecl = 0; 3220 if (!AllowOverloadingOfFunction(Previous, Context)) { 3221 Redeclaration = true; 3222 OldDecl = Previous.getFoundDecl(); 3223 } else { 3224 if (!getLangOptions().CPlusPlus) { 3225 OverloadableAttrRequired = true; 3226 3227 // Functions marked "overloadable" must have a prototype (that 3228 // we can't get through declaration merging). 3229 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3230 Diag(NewFD->getLocation(), 3231 diag::err_attribute_overloadable_no_prototype) 3232 << NewFD; 3233 Redeclaration = true; 3234 3235 // Turn this into a variadic function with no parameters. 3236 QualType R = Context.getFunctionType( 3237 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3238 0, 0, true, 0); 3239 NewFD->setType(R); 3240 return NewFD->setInvalidDecl(); 3241 } 3242 } 3243 3244 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3245 case Ovl_Match: 3246 Redeclaration = true; 3247 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3248 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3249 Redeclaration = false; 3250 } 3251 break; 3252 3253 case Ovl_NonFunction: 3254 Redeclaration = true; 3255 break; 3256 3257 case Ovl_Overload: 3258 Redeclaration = false; 3259 break; 3260 } 3261 } 3262 3263 if (Redeclaration) { 3264 // NewFD and OldDecl represent declarations that need to be 3265 // merged. 3266 if (MergeFunctionDecl(NewFD, OldDecl)) 3267 return NewFD->setInvalidDecl(); 3268 3269 Previous.clear(); 3270 Previous.addDecl(OldDecl); 3271 3272 if (FunctionTemplateDecl *OldTemplateDecl 3273 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3274 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3275 FunctionTemplateDecl *NewTemplateDecl 3276 = NewFD->getDescribedFunctionTemplate(); 3277 assert(NewTemplateDecl && "Template/non-template mismatch"); 3278 if (CXXMethodDecl *Method 3279 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3280 Method->setAccess(OldTemplateDecl->getAccess()); 3281 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3282 } 3283 3284 // If this is an explicit specialization of a member that is a function 3285 // template, mark it as a member specialization. 3286 if (IsExplicitSpecialization && 3287 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3288 NewTemplateDecl->setMemberSpecialization(); 3289 assert(OldTemplateDecl->isMemberSpecialization()); 3290 } 3291 } else { 3292 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3293 NewFD->setAccess(OldDecl->getAccess()); 3294 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3295 } 3296 } 3297 } 3298 3299 // Semantic checking for this function declaration (in isolation). 3300 if (getLangOptions().CPlusPlus) { 3301 // C++-specific checks. 3302 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3303 CheckConstructor(Constructor); 3304 } else if (CXXDestructorDecl *Destructor = 3305 dyn_cast<CXXDestructorDecl>(NewFD)) { 3306 CXXRecordDecl *Record = Destructor->getParent(); 3307 QualType ClassType = Context.getTypeDeclType(Record); 3308 3309 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3310 // type is dependent? Both gcc and edg can handle that. 3311 if (!ClassType->isDependentType()) { 3312 DeclarationName Name 3313 = Context.DeclarationNames.getCXXDestructorName( 3314 Context.getCanonicalType(ClassType)); 3315 if (NewFD->getDeclName() != Name) { 3316 Diag(NewFD->getLocation(), diag::err_destructor_name); 3317 return NewFD->setInvalidDecl(); 3318 } 3319 } 3320 3321 Record->setUserDeclaredDestructor(true); 3322 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3323 // user-defined destructor. 3324 Record->setPOD(false); 3325 3326 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3327 // declared destructor. 3328 // FIXME: C++0x: don't do this for "= default" destructors 3329 Record->setHasTrivialDestructor(false); 3330 } else if (CXXConversionDecl *Conversion 3331 = dyn_cast<CXXConversionDecl>(NewFD)) { 3332 ActOnConversionDeclarator(Conversion); 3333 } 3334 3335 // Find any virtual functions that this function overrides. 3336 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3337 if (!Method->isFunctionTemplateSpecialization() && 3338 !Method->getDescribedFunctionTemplate()) 3339 AddOverriddenMethods(Method->getParent(), Method); 3340 } 3341 3342 // Additional checks for the destructor; make sure we do this after we 3343 // figure out whether the destructor is virtual. 3344 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3345 if (!Destructor->getParent()->isDependentType()) 3346 CheckDestructor(Destructor); 3347 3348 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3349 if (NewFD->isOverloadedOperator() && 3350 CheckOverloadedOperatorDeclaration(NewFD)) 3351 return NewFD->setInvalidDecl(); 3352 3353 // In C++, check default arguments now that we have merged decls. Unless 3354 // the lexical context is the class, because in this case this is done 3355 // during delayed parsing anyway. 3356 if (!CurContext->isRecord()) 3357 CheckCXXDefaultArguments(NewFD); 3358 } 3359} 3360 3361void Sema::CheckMain(FunctionDecl* FD) { 3362 // C++ [basic.start.main]p3: A program that declares main to be inline 3363 // or static is ill-formed. 3364 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3365 // shall not appear in a declaration of main. 3366 // static main is not an error under C99, but we should warn about it. 3367 bool isInline = FD->isInlineSpecified(); 3368 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3369 if (isInline || isStatic) { 3370 unsigned diagID = diag::warn_unusual_main_decl; 3371 if (isInline || getLangOptions().CPlusPlus) 3372 diagID = diag::err_unusual_main_decl; 3373 3374 int which = isStatic + (isInline << 1) - 1; 3375 Diag(FD->getLocation(), diagID) << which; 3376 } 3377 3378 QualType T = FD->getType(); 3379 assert(T->isFunctionType() && "function decl is not of function type"); 3380 const FunctionType* FT = T->getAs<FunctionType>(); 3381 3382 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3383 // TODO: add a replacement fixit to turn the return type into 'int'. 3384 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3385 FD->setInvalidDecl(true); 3386 } 3387 3388 // Treat protoless main() as nullary. 3389 if (isa<FunctionNoProtoType>(FT)) return; 3390 3391 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3392 unsigned nparams = FTP->getNumArgs(); 3393 assert(FD->getNumParams() == nparams); 3394 3395 if (nparams > 3) { 3396 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3397 FD->setInvalidDecl(true); 3398 nparams = 3; 3399 } 3400 3401 // FIXME: a lot of the following diagnostics would be improved 3402 // if we had some location information about types. 3403 3404 QualType CharPP = 3405 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3406 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3407 3408 for (unsigned i = 0; i < nparams; ++i) { 3409 QualType AT = FTP->getArgType(i); 3410 3411 bool mismatch = true; 3412 3413 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3414 mismatch = false; 3415 else if (Expected[i] == CharPP) { 3416 // As an extension, the following forms are okay: 3417 // char const ** 3418 // char const * const * 3419 // char * const * 3420 3421 QualifierCollector qs; 3422 const PointerType* PT; 3423 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3424 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3425 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3426 qs.removeConst(); 3427 mismatch = !qs.empty(); 3428 } 3429 } 3430 3431 if (mismatch) { 3432 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3433 // TODO: suggest replacing given type with expected type 3434 FD->setInvalidDecl(true); 3435 } 3436 } 3437 3438 if (nparams == 1 && !FD->isInvalidDecl()) { 3439 Diag(FD->getLocation(), diag::warn_main_one_arg); 3440 } 3441} 3442 3443bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3444 // FIXME: Need strict checking. In C89, we need to check for 3445 // any assignment, increment, decrement, function-calls, or 3446 // commas outside of a sizeof. In C99, it's the same list, 3447 // except that the aforementioned are allowed in unevaluated 3448 // expressions. Everything else falls under the 3449 // "may accept other forms of constant expressions" exception. 3450 // (We never end up here for C++, so the constant expression 3451 // rules there don't matter.) 3452 if (Init->isConstantInitializer(Context)) 3453 return false; 3454 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3455 << Init->getSourceRange(); 3456 return true; 3457} 3458 3459void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3460 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3461} 3462 3463/// AddInitializerToDecl - Adds the initializer Init to the 3464/// declaration dcl. If DirectInit is true, this is C++ direct 3465/// initialization rather than copy initialization. 3466void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3467 Decl *RealDecl = dcl.getAs<Decl>(); 3468 // If there is no declaration, there was an error parsing it. Just ignore 3469 // the initializer. 3470 if (RealDecl == 0) 3471 return; 3472 3473 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3474 // With declarators parsed the way they are, the parser cannot 3475 // distinguish between a normal initializer and a pure-specifier. 3476 // Thus this grotesque test. 3477 IntegerLiteral *IL; 3478 Expr *Init = static_cast<Expr *>(init.get()); 3479 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3480 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3481 CheckPureMethod(Method, Init->getSourceRange()); 3482 else { 3483 Diag(Method->getLocation(), diag::err_member_function_initialization) 3484 << Method->getDeclName() << Init->getSourceRange(); 3485 Method->setInvalidDecl(); 3486 } 3487 return; 3488 } 3489 3490 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3491 if (!VDecl) { 3492 if (getLangOptions().CPlusPlus && 3493 RealDecl->getLexicalDeclContext()->isRecord() && 3494 isa<NamedDecl>(RealDecl)) 3495 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3496 << cast<NamedDecl>(RealDecl)->getDeclName(); 3497 else 3498 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3499 RealDecl->setInvalidDecl(); 3500 return; 3501 } 3502 3503 // A definition must end up with a complete type, which means it must be 3504 // complete with the restriction that an array type might be completed by the 3505 // initializer; note that later code assumes this restriction. 3506 QualType BaseDeclType = VDecl->getType(); 3507 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3508 BaseDeclType = Array->getElementType(); 3509 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3510 diag::err_typecheck_decl_incomplete_type)) { 3511 RealDecl->setInvalidDecl(); 3512 return; 3513 } 3514 3515 // The variable can not have an abstract class type. 3516 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3517 diag::err_abstract_type_in_decl, 3518 AbstractVariableType)) 3519 VDecl->setInvalidDecl(); 3520 3521 const VarDecl *Def = 0; 3522 if (VDecl->getDefinition(Def)) { 3523 Diag(VDecl->getLocation(), diag::err_redefinition) 3524 << VDecl->getDeclName(); 3525 Diag(Def->getLocation(), diag::note_previous_definition); 3526 VDecl->setInvalidDecl(); 3527 return; 3528 } 3529 3530 // Take ownership of the expression, now that we're sure we have somewhere 3531 // to put it. 3532 Expr *Init = init.takeAs<Expr>(); 3533 assert(Init && "missing initializer"); 3534 3535 // Capture the variable that is being initialized and the style of 3536 // initialization. 3537 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3538 3539 // FIXME: Poor source location information. 3540 InitializationKind Kind 3541 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3542 Init->getLocStart(), 3543 Init->getLocEnd()) 3544 : InitializationKind::CreateCopy(VDecl->getLocation(), 3545 Init->getLocStart()); 3546 3547 // Get the decls type and save a reference for later, since 3548 // CheckInitializerTypes may change it. 3549 QualType DclT = VDecl->getType(), SavT = DclT; 3550 if (VDecl->isBlockVarDecl()) { 3551 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3552 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3553 VDecl->setInvalidDecl(); 3554 } else if (!VDecl->isInvalidDecl()) { 3555 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3556 if (InitSeq) { 3557 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3558 MultiExprArg(*this, (void**)&Init, 1), 3559 &DclT); 3560 if (Result.isInvalid()) { 3561 VDecl->setInvalidDecl(); 3562 return; 3563 } 3564 3565 Init = Result.takeAs<Expr>(); 3566 } else { 3567 InitSeq.Diagnose(*this, Entity, Kind, &Init, 1); 3568 VDecl->setInvalidDecl(); 3569 return; 3570 } 3571 3572 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3573 // Don't check invalid declarations to avoid emitting useless diagnostics. 3574 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3575 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3576 CheckForConstantInitializer(Init, DclT); 3577 } 3578 } 3579 } else if (VDecl->isStaticDataMember() && 3580 VDecl->getLexicalDeclContext()->isRecord()) { 3581 // This is an in-class initialization for a static data member, e.g., 3582 // 3583 // struct S { 3584 // static const int value = 17; 3585 // }; 3586 3587 // Attach the initializer 3588 VDecl->setInit(Context, Init); 3589 3590 // C++ [class.mem]p4: 3591 // A member-declarator can contain a constant-initializer only 3592 // if it declares a static member (9.4) of const integral or 3593 // const enumeration type, see 9.4.2. 3594 QualType T = VDecl->getType(); 3595 if (!T->isDependentType() && 3596 (!Context.getCanonicalType(T).isConstQualified() || 3597 !T->isIntegralType())) { 3598 Diag(VDecl->getLocation(), diag::err_member_initialization) 3599 << VDecl->getDeclName() << Init->getSourceRange(); 3600 VDecl->setInvalidDecl(); 3601 } else { 3602 // C++ [class.static.data]p4: 3603 // If a static data member is of const integral or const 3604 // enumeration type, its declaration in the class definition 3605 // can specify a constant-initializer which shall be an 3606 // integral constant expression (5.19). 3607 if (!Init->isTypeDependent() && 3608 !Init->getType()->isIntegralType()) { 3609 // We have a non-dependent, non-integral or enumeration type. 3610 Diag(Init->getSourceRange().getBegin(), 3611 diag::err_in_class_initializer_non_integral_type) 3612 << Init->getType() << Init->getSourceRange(); 3613 VDecl->setInvalidDecl(); 3614 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3615 // Check whether the expression is a constant expression. 3616 llvm::APSInt Value; 3617 SourceLocation Loc; 3618 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3619 Diag(Loc, diag::err_in_class_initializer_non_constant) 3620 << Init->getSourceRange(); 3621 VDecl->setInvalidDecl(); 3622 } else if (!VDecl->getType()->isDependentType()) 3623 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3624 } 3625 } 3626 } else if (VDecl->isFileVarDecl()) { 3627 if (VDecl->getStorageClass() == VarDecl::Extern) 3628 Diag(VDecl->getLocation(), diag::warn_extern_init); 3629 if (!VDecl->isInvalidDecl()) 3630 if (CheckInitializerTypes(Init, DclT, Entity, Kind)) 3631 VDecl->setInvalidDecl(); 3632 3633 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3634 // Don't check invalid declarations to avoid emitting useless diagnostics. 3635 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3636 // C99 6.7.8p4. All file scoped initializers need to be constant. 3637 CheckForConstantInitializer(Init, DclT); 3638 } 3639 } 3640 // If the type changed, it means we had an incomplete type that was 3641 // completed by the initializer. For example: 3642 // int ary[] = { 1, 3, 5 }; 3643 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3644 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3645 VDecl->setType(DclT); 3646 Init->setType(DclT); 3647 } 3648 3649 Init = MaybeCreateCXXExprWithTemporaries(Init); 3650 // Attach the initializer to the decl. 3651 VDecl->setInit(Context, Init); 3652 3653 // If the previous declaration of VDecl was a tentative definition, 3654 // remove it from the set of tentative definitions. 3655 if (VDecl->getPreviousDeclaration() && 3656 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3657 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3658 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3659 } 3660 3661 return; 3662} 3663 3664void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3665 bool TypeContainsUndeducedAuto) { 3666 Decl *RealDecl = dcl.getAs<Decl>(); 3667 3668 // If there is no declaration, there was an error parsing it. Just ignore it. 3669 if (RealDecl == 0) 3670 return; 3671 3672 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3673 QualType Type = Var->getType(); 3674 3675 // Record tentative definitions. 3676 if (Var->isTentativeDefinition(Context)) { 3677 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3678 InsertPair = 3679 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3680 3681 // Keep the latest definition in the map. If we see 'int i; int i;' we 3682 // want the second one in the map. 3683 InsertPair.first->second = Var; 3684 3685 // However, for the list, we don't care about the order, just make sure 3686 // that there are no dupes for a given declaration name. 3687 if (InsertPair.second) 3688 TentativeDefinitionList.push_back(Var->getDeclName()); 3689 } 3690 3691 // C++ [dcl.init.ref]p3: 3692 // The initializer can be omitted for a reference only in a 3693 // parameter declaration (8.3.5), in the declaration of a 3694 // function return type, in the declaration of a class member 3695 // within its class declaration (9.2), and where the extern 3696 // specifier is explicitly used. 3697 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3698 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3699 << Var->getDeclName() 3700 << SourceRange(Var->getLocation(), Var->getLocation()); 3701 Var->setInvalidDecl(); 3702 return; 3703 } 3704 3705 // C++0x [dcl.spec.auto]p3 3706 if (TypeContainsUndeducedAuto) { 3707 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3708 << Var->getDeclName() << Type; 3709 Var->setInvalidDecl(); 3710 return; 3711 } 3712 3713 // An array without size is an incomplete type, and there are no special 3714 // rules in C++ to make such a definition acceptable. 3715 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3716 !Var->hasExternalStorage()) { 3717 Diag(Var->getLocation(), 3718 diag::err_typecheck_incomplete_array_needs_initializer); 3719 Var->setInvalidDecl(); 3720 return; 3721 } 3722 3723 // C++ [temp.expl.spec]p15: 3724 // An explicit specialization of a static data member of a template is a 3725 // definition if the declaration includes an initializer; otherwise, it 3726 // is a declaration. 3727 if (Var->isStaticDataMember() && 3728 Var->getInstantiatedFromStaticDataMember() && 3729 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3730 return; 3731 3732 // C++ [dcl.init]p9: 3733 // If no initializer is specified for an object, and the object 3734 // is of (possibly cv-qualified) non-POD class type (or array 3735 // thereof), the object shall be default-initialized; if the 3736 // object is of const-qualified type, the underlying class type 3737 // shall have a user-declared default constructor. 3738 // 3739 // FIXME: Diagnose the "user-declared default constructor" bit. 3740 if (getLangOptions().CPlusPlus) { 3741 QualType InitType = Type; 3742 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3743 InitType = Context.getBaseElementType(Array); 3744 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3745 InitType->isRecordType() && !InitType->isDependentType()) { 3746 if (!RequireCompleteType(Var->getLocation(), InitType, 3747 diag::err_invalid_incomplete_type_use)) { 3748 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3749 3750 CXXConstructorDecl *Constructor 3751 = PerformInitializationByConstructor(InitType, 3752 MultiExprArg(*this, 0, 0), 3753 Var->getLocation(), 3754 SourceRange(Var->getLocation(), 3755 Var->getLocation()), 3756 Var->getDeclName(), 3757 InitializationKind::CreateDefault(Var->getLocation()), 3758 ConstructorArgs); 3759 3760 // FIXME: Location info for the variable initialization? 3761 if (!Constructor) 3762 Var->setInvalidDecl(); 3763 else { 3764 // FIXME: Cope with initialization of arrays 3765 if (!Constructor->isTrivial() && 3766 InitializeVarWithConstructor(Var, Constructor, 3767 move_arg(ConstructorArgs))) 3768 Var->setInvalidDecl(); 3769 3770 FinalizeVarWithDestructor(Var, InitType); 3771 } 3772 } else { 3773 Var->setInvalidDecl(); 3774 } 3775 } 3776 3777 // The variable can not have an abstract class type. 3778 if (RequireNonAbstractType(Var->getLocation(), Type, 3779 diag::err_abstract_type_in_decl, 3780 AbstractVariableType)) 3781 Var->setInvalidDecl(); 3782 } 3783 3784#if 0 3785 // FIXME: Temporarily disabled because we are not properly parsing 3786 // linkage specifications on declarations, e.g., 3787 // 3788 // extern "C" const CGPoint CGPointerZero; 3789 // 3790 // C++ [dcl.init]p9: 3791 // 3792 // If no initializer is specified for an object, and the 3793 // object is of (possibly cv-qualified) non-POD class type (or 3794 // array thereof), the object shall be default-initialized; if 3795 // the object is of const-qualified type, the underlying class 3796 // type shall have a user-declared default 3797 // constructor. Otherwise, if no initializer is specified for 3798 // an object, the object and its subobjects, if any, have an 3799 // indeterminate initial value; if the object or any of its 3800 // subobjects are of const-qualified type, the program is 3801 // ill-formed. 3802 // 3803 // This isn't technically an error in C, so we don't diagnose it. 3804 // 3805 // FIXME: Actually perform the POD/user-defined default 3806 // constructor check. 3807 if (getLangOptions().CPlusPlus && 3808 Context.getCanonicalType(Type).isConstQualified() && 3809 !Var->hasExternalStorage()) 3810 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3811 << Var->getName() 3812 << SourceRange(Var->getLocation(), Var->getLocation()); 3813#endif 3814 } 3815} 3816 3817Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3818 DeclPtrTy *Group, 3819 unsigned NumDecls) { 3820 llvm::SmallVector<Decl*, 8> Decls; 3821 3822 if (DS.isTypeSpecOwned()) 3823 Decls.push_back((Decl*)DS.getTypeRep()); 3824 3825 for (unsigned i = 0; i != NumDecls; ++i) 3826 if (Decl *D = Group[i].getAs<Decl>()) 3827 Decls.push_back(D); 3828 3829 // Perform semantic analysis that depends on having fully processed both 3830 // the declarator and initializer. 3831 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3832 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3833 if (!IDecl) 3834 continue; 3835 QualType T = IDecl->getType(); 3836 3837 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3838 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3839 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3840 if (T->isDependentType()) { 3841 // If T is dependent, we should not require a complete type. 3842 // (RequireCompleteType shouldn't be called with dependent types.) 3843 // But we still can at least check if we've got an array of unspecified 3844 // size without an initializer. 3845 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3846 !IDecl->getInit()) { 3847 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3848 << T; 3849 IDecl->setInvalidDecl(); 3850 } 3851 } else if (!IDecl->isInvalidDecl()) { 3852 // If T is an incomplete array type with an initializer list that is 3853 // dependent on something, its size has not been fixed. We could attempt 3854 // to fix the size for such arrays, but we would still have to check 3855 // here for initializers containing a C++0x vararg expansion, e.g. 3856 // template <typename... Args> void f(Args... args) { 3857 // int vals[] = { args }; 3858 // } 3859 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3860 Expr *Init = IDecl->getInit(); 3861 if (IAT && Init && 3862 (Init->isTypeDependent() || Init->isValueDependent())) { 3863 // Check that the member type of the array is complete, at least. 3864 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3865 diag::err_typecheck_decl_incomplete_type)) 3866 IDecl->setInvalidDecl(); 3867 } else if (RequireCompleteType(IDecl->getLocation(), T, 3868 diag::err_typecheck_decl_incomplete_type)) 3869 IDecl->setInvalidDecl(); 3870 } 3871 } 3872 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3873 // object that has file scope without an initializer, and without a 3874 // storage-class specifier or with the storage-class specifier "static", 3875 // constitutes a tentative definition. Note: A tentative definition with 3876 // external linkage is valid (C99 6.2.2p5). 3877 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3878 if (const IncompleteArrayType *ArrayT 3879 = Context.getAsIncompleteArrayType(T)) { 3880 if (RequireCompleteType(IDecl->getLocation(), 3881 ArrayT->getElementType(), 3882 diag::err_illegal_decl_array_incomplete_type)) 3883 IDecl->setInvalidDecl(); 3884 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3885 // C99 6.9.2p3: If the declaration of an identifier for an object is 3886 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3887 // declared type shall not be an incomplete type. 3888 // NOTE: code such as the following 3889 // static struct s; 3890 // struct s { int a; }; 3891 // is accepted by gcc. Hence here we issue a warning instead of 3892 // an error and we do not invalidate the static declaration. 3893 // NOTE: to avoid multiple warnings, only check the first declaration. 3894 if (IDecl->getPreviousDeclaration() == 0) 3895 RequireCompleteType(IDecl->getLocation(), T, 3896 diag::ext_typecheck_decl_incomplete_type); 3897 } 3898 } 3899 } 3900 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3901 Decls.data(), Decls.size())); 3902} 3903 3904 3905/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3906/// to introduce parameters into function prototype scope. 3907Sema::DeclPtrTy 3908Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3909 const DeclSpec &DS = D.getDeclSpec(); 3910 3911 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3912 VarDecl::StorageClass StorageClass = VarDecl::None; 3913 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3914 StorageClass = VarDecl::Register; 3915 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3916 Diag(DS.getStorageClassSpecLoc(), 3917 diag::err_invalid_storage_class_in_func_decl); 3918 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3919 } 3920 3921 if (D.getDeclSpec().isThreadSpecified()) 3922 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3923 3924 DiagnoseFunctionSpecifiers(D); 3925 3926 // Check that there are no default arguments inside the type of this 3927 // parameter (C++ only). 3928 if (getLangOptions().CPlusPlus) 3929 CheckExtraCXXDefaultArguments(D); 3930 3931 TypeSourceInfo *TInfo = 0; 3932 TagDecl *OwnedDecl = 0; 3933 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3934 3935 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3936 // C++ [dcl.fct]p6: 3937 // Types shall not be defined in return or parameter types. 3938 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3939 << Context.getTypeDeclType(OwnedDecl); 3940 } 3941 3942 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3943 // Can this happen for params? We already checked that they don't conflict 3944 // among each other. Here they can only shadow globals, which is ok. 3945 IdentifierInfo *II = D.getIdentifier(); 3946 if (II) { 3947 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3948 if (PrevDecl->isTemplateParameter()) { 3949 // Maybe we will complain about the shadowed template parameter. 3950 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3951 // Just pretend that we didn't see the previous declaration. 3952 PrevDecl = 0; 3953 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3954 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3955 3956 // Recover by removing the name 3957 II = 0; 3958 D.SetIdentifier(0, D.getIdentifierLoc()); 3959 } 3960 } 3961 } 3962 3963 // Parameters can not be abstract class types. 3964 // For record types, this is done by the AbstractClassUsageDiagnoser once 3965 // the class has been completely parsed. 3966 if (!CurContext->isRecord() && 3967 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3968 diag::err_abstract_type_in_decl, 3969 AbstractParamType)) 3970 D.setInvalidType(true); 3971 3972 QualType T = adjustParameterType(parmDeclType); 3973 3974 ParmVarDecl *New 3975 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3976 T, TInfo, StorageClass, 0); 3977 3978 if (D.isInvalidType()) 3979 New->setInvalidDecl(); 3980 3981 // Parameter declarators cannot be interface types. All ObjC objects are 3982 // passed by reference. 3983 if (T->isObjCInterfaceType()) { 3984 Diag(D.getIdentifierLoc(), 3985 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3986 New->setInvalidDecl(); 3987 } 3988 3989 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3990 if (D.getCXXScopeSpec().isSet()) { 3991 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3992 << D.getCXXScopeSpec().getRange(); 3993 New->setInvalidDecl(); 3994 } 3995 3996 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3997 // duration shall not be qualified by an address-space qualifier." 3998 // Since all parameters have automatic store duration, they can not have 3999 // an address space. 4000 if (T.getAddressSpace() != 0) { 4001 Diag(D.getIdentifierLoc(), 4002 diag::err_arg_with_address_space); 4003 New->setInvalidDecl(); 4004 } 4005 4006 4007 // Add the parameter declaration into this scope. 4008 S->AddDecl(DeclPtrTy::make(New)); 4009 if (II) 4010 IdResolver.AddDecl(New); 4011 4012 ProcessDeclAttributes(S, New, D); 4013 4014 if (New->hasAttr<BlocksAttr>()) { 4015 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4016 } 4017 return DeclPtrTy::make(New); 4018} 4019 4020void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4021 SourceLocation LocAfterDecls) { 4022 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4023 "Not a function declarator!"); 4024 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4025 4026 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4027 // for a K&R function. 4028 if (!FTI.hasPrototype) { 4029 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4030 --i; 4031 if (FTI.ArgInfo[i].Param == 0) { 4032 llvm::SmallString<256> Code; 4033 llvm::raw_svector_ostream(Code) << " int " 4034 << FTI.ArgInfo[i].Ident->getName() 4035 << ";\n"; 4036 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4037 << FTI.ArgInfo[i].Ident 4038 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4039 4040 // Implicitly declare the argument as type 'int' for lack of a better 4041 // type. 4042 DeclSpec DS; 4043 const char* PrevSpec; // unused 4044 unsigned DiagID; // unused 4045 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4046 PrevSpec, DiagID); 4047 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4048 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4049 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4050 } 4051 } 4052 } 4053} 4054 4055Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4056 Declarator &D) { 4057 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4058 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4059 "Not a function declarator!"); 4060 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4061 4062 if (FTI.hasPrototype) { 4063 // FIXME: Diagnose arguments without names in C. 4064 } 4065 4066 Scope *ParentScope = FnBodyScope->getParent(); 4067 4068 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4069 MultiTemplateParamsArg(*this), 4070 /*IsFunctionDefinition=*/true); 4071 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4072} 4073 4074static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4075 // Don't warn about invalid declarations. 4076 if (FD->isInvalidDecl()) 4077 return false; 4078 4079 // Or declarations that aren't global. 4080 if (!FD->isGlobal()) 4081 return false; 4082 4083 // Don't warn about C++ member functions. 4084 if (isa<CXXMethodDecl>(FD)) 4085 return false; 4086 4087 // Don't warn about 'main'. 4088 if (FD->isMain()) 4089 return false; 4090 4091 // Don't warn about inline functions. 4092 if (FD->isInlineSpecified()) 4093 return false; 4094 4095 // Don't warn about function templates. 4096 if (FD->getDescribedFunctionTemplate()) 4097 return false; 4098 4099 // Don't warn about function template specializations. 4100 if (FD->isFunctionTemplateSpecialization()) 4101 return false; 4102 4103 bool MissingPrototype = true; 4104 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4105 Prev; Prev = Prev->getPreviousDeclaration()) { 4106 // Ignore any declarations that occur in function or method 4107 // scope, because they aren't visible from the header. 4108 if (Prev->getDeclContext()->isFunctionOrMethod()) 4109 continue; 4110 4111 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4112 break; 4113 } 4114 4115 return MissingPrototype; 4116} 4117 4118Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4119 // Clear the last template instantiation error context. 4120 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4121 4122 if (!D) 4123 return D; 4124 FunctionDecl *FD = 0; 4125 4126 if (FunctionTemplateDecl *FunTmpl 4127 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4128 FD = FunTmpl->getTemplatedDecl(); 4129 else 4130 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4131 4132 CurFunctionNeedsScopeChecking = false; 4133 4134 // See if this is a redefinition. 4135 const FunctionDecl *Definition; 4136 if (FD->getBody(Definition)) { 4137 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4138 Diag(Definition->getLocation(), diag::note_previous_definition); 4139 } 4140 4141 // Builtin functions cannot be defined. 4142 if (unsigned BuiltinID = FD->getBuiltinID()) { 4143 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4144 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4145 FD->setInvalidDecl(); 4146 } 4147 } 4148 4149 // The return type of a function definition must be complete 4150 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4151 QualType ResultType = FD->getResultType(); 4152 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4153 !FD->isInvalidDecl() && 4154 RequireCompleteType(FD->getLocation(), ResultType, 4155 diag::err_func_def_incomplete_result)) 4156 FD->setInvalidDecl(); 4157 4158 // GNU warning -Wmissing-prototypes: 4159 // Warn if a global function is defined without a previous 4160 // prototype declaration. This warning is issued even if the 4161 // definition itself provides a prototype. The aim is to detect 4162 // global functions that fail to be declared in header files. 4163 if (ShouldWarnAboutMissingPrototype(FD)) 4164 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4165 4166 if (FnBodyScope) 4167 PushDeclContext(FnBodyScope, FD); 4168 4169 // Check the validity of our function parameters 4170 CheckParmsForFunctionDef(FD); 4171 4172 // Introduce our parameters into the function scope 4173 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4174 ParmVarDecl *Param = FD->getParamDecl(p); 4175 Param->setOwningFunction(FD); 4176 4177 // If this has an identifier, add it to the scope stack. 4178 if (Param->getIdentifier() && FnBodyScope) 4179 PushOnScopeChains(Param, FnBodyScope); 4180 } 4181 4182 // Checking attributes of current function definition 4183 // dllimport attribute. 4184 if (FD->getAttr<DLLImportAttr>() && 4185 (!FD->getAttr<DLLExportAttr>())) { 4186 // dllimport attribute cannot be applied to definition. 4187 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4188 Diag(FD->getLocation(), 4189 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4190 << "dllimport"; 4191 FD->setInvalidDecl(); 4192 return DeclPtrTy::make(FD); 4193 } else { 4194 // If a symbol previously declared dllimport is later defined, the 4195 // attribute is ignored in subsequent references, and a warning is 4196 // emitted. 4197 Diag(FD->getLocation(), 4198 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4199 << FD->getNameAsCString() << "dllimport"; 4200 } 4201 } 4202 return DeclPtrTy::make(FD); 4203} 4204 4205Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4206 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4207} 4208 4209Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4210 bool IsInstantiation) { 4211 Decl *dcl = D.getAs<Decl>(); 4212 Stmt *Body = BodyArg.takeAs<Stmt>(); 4213 4214 FunctionDecl *FD = 0; 4215 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4216 if (FunTmpl) 4217 FD = FunTmpl->getTemplatedDecl(); 4218 else 4219 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4220 4221 if (FD) { 4222 FD->setBody(Body); 4223 if (FD->isMain()) 4224 // C and C++ allow for main to automagically return 0. 4225 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4226 FD->setHasImplicitReturnZero(true); 4227 else 4228 CheckFallThroughForFunctionDef(FD, Body); 4229 4230 if (!FD->isInvalidDecl()) 4231 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4232 4233 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4234 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4235 4236 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4237 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4238 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4239 MD->setBody(Body); 4240 CheckFallThroughForFunctionDef(MD, Body); 4241 MD->setEndLoc(Body->getLocEnd()); 4242 4243 if (!MD->isInvalidDecl()) 4244 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4245 } else { 4246 Body->Destroy(Context); 4247 return DeclPtrTy(); 4248 } 4249 if (!IsInstantiation) 4250 PopDeclContext(); 4251 4252 // Verify and clean out per-function state. 4253 4254 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4255 4256 // Check goto/label use. 4257 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4258 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4259 LabelStmt *L = I->second; 4260 4261 // Verify that we have no forward references left. If so, there was a goto 4262 // or address of a label taken, but no definition of it. Label fwd 4263 // definitions are indicated with a null substmt. 4264 if (L->getSubStmt() != 0) 4265 continue; 4266 4267 // Emit error. 4268 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4269 4270 // At this point, we have gotos that use the bogus label. Stitch it into 4271 // the function body so that they aren't leaked and that the AST is well 4272 // formed. 4273 if (Body == 0) { 4274 // The whole function wasn't parsed correctly, just delete this. 4275 L->Destroy(Context); 4276 continue; 4277 } 4278 4279 // Otherwise, the body is valid: we want to stitch the label decl into the 4280 // function somewhere so that it is properly owned and so that the goto 4281 // has a valid target. Do this by creating a new compound stmt with the 4282 // label in it. 4283 4284 // Give the label a sub-statement. 4285 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4286 4287 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4288 cast<CXXTryStmt>(Body)->getTryBlock() : 4289 cast<CompoundStmt>(Body); 4290 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4291 Elements.push_back(L); 4292 Compound->setStmts(Context, &Elements[0], Elements.size()); 4293 } 4294 FunctionLabelMap.clear(); 4295 4296 if (!Body) return D; 4297 4298 // Verify that that gotos and switch cases don't jump into scopes illegally. 4299 if (CurFunctionNeedsScopeChecking) 4300 DiagnoseInvalidJumps(Body); 4301 4302 // C++ constructors that have function-try-blocks can't have return 4303 // statements in the handlers of that block. (C++ [except.handle]p14) 4304 // Verify this. 4305 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4306 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4307 4308 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4309 MarkBaseAndMemberDestructorsReferenced(Destructor); 4310 4311 // If any errors have occurred, clear out any temporaries that may have 4312 // been leftover. This ensures that these temporaries won't be picked up for 4313 // deletion in some later function. 4314 if (PP.getDiagnostics().hasErrorOccurred()) 4315 ExprTemporaries.clear(); 4316 4317 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4318 return D; 4319} 4320 4321/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4322/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4323NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4324 IdentifierInfo &II, Scope *S) { 4325 // Before we produce a declaration for an implicitly defined 4326 // function, see whether there was a locally-scoped declaration of 4327 // this name as a function or variable. If so, use that 4328 // (non-visible) declaration, and complain about it. 4329 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4330 = LocallyScopedExternalDecls.find(&II); 4331 if (Pos != LocallyScopedExternalDecls.end()) { 4332 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4333 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4334 return Pos->second; 4335 } 4336 4337 // Extension in C99. Legal in C90, but warn about it. 4338 if (II.getName().startswith("__builtin_")) 4339 Diag(Loc, diag::warn_builtin_unknown) << &II; 4340 else if (getLangOptions().C99) 4341 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4342 else 4343 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4344 4345 // Set a Declarator for the implicit definition: int foo(); 4346 const char *Dummy; 4347 DeclSpec DS; 4348 unsigned DiagID; 4349 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4350 Error = Error; // Silence warning. 4351 assert(!Error && "Error setting up implicit decl!"); 4352 Declarator D(DS, Declarator::BlockContext); 4353 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4354 0, 0, false, SourceLocation(), 4355 false, 0,0,0, Loc, Loc, D), 4356 SourceLocation()); 4357 D.SetIdentifier(&II, Loc); 4358 4359 // Insert this function into translation-unit scope. 4360 4361 DeclContext *PrevDC = CurContext; 4362 CurContext = Context.getTranslationUnitDecl(); 4363 4364 FunctionDecl *FD = 4365 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4366 FD->setImplicit(); 4367 4368 CurContext = PrevDC; 4369 4370 AddKnownFunctionAttributes(FD); 4371 4372 return FD; 4373} 4374 4375/// \brief Adds any function attributes that we know a priori based on 4376/// the declaration of this function. 4377/// 4378/// These attributes can apply both to implicitly-declared builtins 4379/// (like __builtin___printf_chk) or to library-declared functions 4380/// like NSLog or printf. 4381void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4382 if (FD->isInvalidDecl()) 4383 return; 4384 4385 // If this is a built-in function, map its builtin attributes to 4386 // actual attributes. 4387 if (unsigned BuiltinID = FD->getBuiltinID()) { 4388 // Handle printf-formatting attributes. 4389 unsigned FormatIdx; 4390 bool HasVAListArg; 4391 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4392 if (!FD->getAttr<FormatAttr>()) 4393 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4394 HasVAListArg ? 0 : FormatIdx + 2)); 4395 } 4396 4397 // Mark const if we don't care about errno and that is the only 4398 // thing preventing the function from being const. This allows 4399 // IRgen to use LLVM intrinsics for such functions. 4400 if (!getLangOptions().MathErrno && 4401 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4402 if (!FD->getAttr<ConstAttr>()) 4403 FD->addAttr(::new (Context) ConstAttr()); 4404 } 4405 4406 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4407 FD->addAttr(::new (Context) NoReturnAttr()); 4408 } 4409 4410 IdentifierInfo *Name = FD->getIdentifier(); 4411 if (!Name) 4412 return; 4413 if ((!getLangOptions().CPlusPlus && 4414 FD->getDeclContext()->isTranslationUnit()) || 4415 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4416 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4417 LinkageSpecDecl::lang_c)) { 4418 // Okay: this could be a libc/libm/Objective-C function we know 4419 // about. 4420 } else 4421 return; 4422 4423 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4424 // FIXME: NSLog and NSLogv should be target specific 4425 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4426 // FIXME: We known better than our headers. 4427 const_cast<FormatAttr *>(Format)->setType("printf"); 4428 } else 4429 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4430 Name->isStr("NSLogv") ? 0 : 2)); 4431 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4432 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4433 // target-specific builtins, perhaps? 4434 if (!FD->getAttr<FormatAttr>()) 4435 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4436 Name->isStr("vasprintf") ? 0 : 3)); 4437 } 4438} 4439 4440TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4441 TypeSourceInfo *TInfo) { 4442 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4443 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4444 4445 if (!TInfo) { 4446 assert(D.isInvalidType() && "no declarator info for valid type"); 4447 TInfo = Context.getTrivialTypeSourceInfo(T); 4448 } 4449 4450 // Scope manipulation handled by caller. 4451 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4452 D.getIdentifierLoc(), 4453 D.getIdentifier(), 4454 TInfo); 4455 4456 if (const TagType *TT = T->getAs<TagType>()) { 4457 TagDecl *TD = TT->getDecl(); 4458 4459 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4460 // keep track of the TypedefDecl. 4461 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4462 TD->setTypedefForAnonDecl(NewTD); 4463 } 4464 4465 if (D.isInvalidType()) 4466 NewTD->setInvalidDecl(); 4467 return NewTD; 4468} 4469 4470 4471/// \brief Determine whether a tag with a given kind is acceptable 4472/// as a redeclaration of the given tag declaration. 4473/// 4474/// \returns true if the new tag kind is acceptable, false otherwise. 4475bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4476 TagDecl::TagKind NewTag, 4477 SourceLocation NewTagLoc, 4478 const IdentifierInfo &Name) { 4479 // C++ [dcl.type.elab]p3: 4480 // The class-key or enum keyword present in the 4481 // elaborated-type-specifier shall agree in kind with the 4482 // declaration to which the name in theelaborated-type-specifier 4483 // refers. This rule also applies to the form of 4484 // elaborated-type-specifier that declares a class-name or 4485 // friend class since it can be construed as referring to the 4486 // definition of the class. Thus, in any 4487 // elaborated-type-specifier, the enum keyword shall be used to 4488 // refer to an enumeration (7.2), the union class-keyshall be 4489 // used to refer to a union (clause 9), and either the class or 4490 // struct class-key shall be used to refer to a class (clause 9) 4491 // declared using the class or struct class-key. 4492 TagDecl::TagKind OldTag = Previous->getTagKind(); 4493 if (OldTag == NewTag) 4494 return true; 4495 4496 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4497 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4498 // Warn about the struct/class tag mismatch. 4499 bool isTemplate = false; 4500 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4501 isTemplate = Record->getDescribedClassTemplate(); 4502 4503 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4504 << (NewTag == TagDecl::TK_class) 4505 << isTemplate << &Name 4506 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4507 OldTag == TagDecl::TK_class? "class" : "struct"); 4508 Diag(Previous->getLocation(), diag::note_previous_use); 4509 return true; 4510 } 4511 return false; 4512} 4513 4514/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4515/// former case, Name will be non-null. In the later case, Name will be null. 4516/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4517/// reference/declaration/definition of a tag. 4518Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4519 SourceLocation KWLoc, const CXXScopeSpec &SS, 4520 IdentifierInfo *Name, SourceLocation NameLoc, 4521 AttributeList *Attr, AccessSpecifier AS, 4522 MultiTemplateParamsArg TemplateParameterLists, 4523 bool &OwnedDecl, bool &IsDependent) { 4524 // If this is not a definition, it must have a name. 4525 assert((Name != 0 || TUK == TUK_Definition) && 4526 "Nameless record must be a definition!"); 4527 4528 OwnedDecl = false; 4529 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4530 4531 // FIXME: Check explicit specializations more carefully. 4532 bool isExplicitSpecialization = false; 4533 if (TUK != TUK_Reference) { 4534 if (TemplateParameterList *TemplateParams 4535 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4536 (TemplateParameterList**)TemplateParameterLists.get(), 4537 TemplateParameterLists.size(), 4538 isExplicitSpecialization)) { 4539 if (TemplateParams->size() > 0) { 4540 // This is a declaration or definition of a class template (which may 4541 // be a member of another template). 4542 OwnedDecl = false; 4543 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4544 SS, Name, NameLoc, Attr, 4545 TemplateParams, 4546 AS); 4547 TemplateParameterLists.release(); 4548 return Result.get(); 4549 } else { 4550 // The "template<>" header is extraneous. 4551 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4552 << ElaboratedType::getNameForTagKind(Kind) << Name; 4553 isExplicitSpecialization = true; 4554 } 4555 } 4556 4557 TemplateParameterLists.release(); 4558 } 4559 4560 DeclContext *SearchDC = CurContext; 4561 DeclContext *DC = CurContext; 4562 bool isStdBadAlloc = false; 4563 bool Invalid = false; 4564 4565 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4566 : NotForRedeclaration); 4567 4568 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4569 4570 if (Name && SS.isNotEmpty()) { 4571 // We have a nested-name tag ('struct foo::bar'). 4572 4573 // Check for invalid 'foo::'. 4574 if (SS.isInvalid()) { 4575 Name = 0; 4576 goto CreateNewDecl; 4577 } 4578 4579 // If this is a friend or a reference to a class in a dependent 4580 // context, don't try to make a decl for it. 4581 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4582 DC = computeDeclContext(SS, false); 4583 if (!DC) { 4584 IsDependent = true; 4585 return DeclPtrTy(); 4586 } 4587 } 4588 4589 if (RequireCompleteDeclContext(SS)) 4590 return DeclPtrTy::make((Decl *)0); 4591 4592 DC = computeDeclContext(SS, true); 4593 SearchDC = DC; 4594 // Look-up name inside 'foo::'. 4595 LookupQualifiedName(Previous, DC); 4596 4597 if (Previous.isAmbiguous()) 4598 return DeclPtrTy(); 4599 4600 // A tag 'foo::bar' must already exist. 4601 if (Previous.empty()) { 4602 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4603 Name = 0; 4604 Invalid = true; 4605 goto CreateNewDecl; 4606 } 4607 } else if (Name) { 4608 // If this is a named struct, check to see if there was a previous forward 4609 // declaration or definition. 4610 // FIXME: We're looking into outer scopes here, even when we 4611 // shouldn't be. Doing so can result in ambiguities that we 4612 // shouldn't be diagnosing. 4613 LookupName(Previous, S); 4614 4615 // Note: there used to be some attempt at recovery here. 4616 if (Previous.isAmbiguous()) 4617 return DeclPtrTy(); 4618 4619 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4620 // FIXME: This makes sure that we ignore the contexts associated 4621 // with C structs, unions, and enums when looking for a matching 4622 // tag declaration or definition. See the similar lookup tweak 4623 // in Sema::LookupName; is there a better way to deal with this? 4624 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4625 SearchDC = SearchDC->getParent(); 4626 } 4627 } 4628 4629 if (Previous.isSingleResult() && 4630 Previous.getFoundDecl()->isTemplateParameter()) { 4631 // Maybe we will complain about the shadowed template parameter. 4632 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4633 // Just pretend that we didn't see the previous declaration. 4634 Previous.clear(); 4635 } 4636 4637 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4638 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4639 // This is a declaration of or a reference to "std::bad_alloc". 4640 isStdBadAlloc = true; 4641 4642 if (Previous.empty() && StdBadAlloc) { 4643 // std::bad_alloc has been implicitly declared (but made invisible to 4644 // name lookup). Fill in this implicit declaration as the previous 4645 // declaration, so that the declarations get chained appropriately. 4646 Previous.addDecl(StdBadAlloc); 4647 } 4648 } 4649 4650 if (!Previous.empty()) { 4651 assert(Previous.isSingleResult()); 4652 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4653 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4654 // If this is a use of a previous tag, or if the tag is already declared 4655 // in the same scope (so that the definition/declaration completes or 4656 // rementions the tag), reuse the decl. 4657 if (TUK == TUK_Reference || TUK == TUK_Friend || 4658 isDeclInScope(PrevDecl, SearchDC, S)) { 4659 // Make sure that this wasn't declared as an enum and now used as a 4660 // struct or something similar. 4661 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4662 bool SafeToContinue 4663 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4664 Kind != TagDecl::TK_enum); 4665 if (SafeToContinue) 4666 Diag(KWLoc, diag::err_use_with_wrong_tag) 4667 << Name 4668 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4669 PrevTagDecl->getKindName()); 4670 else 4671 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4672 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4673 4674 if (SafeToContinue) 4675 Kind = PrevTagDecl->getTagKind(); 4676 else { 4677 // Recover by making this an anonymous redefinition. 4678 Name = 0; 4679 Previous.clear(); 4680 Invalid = true; 4681 } 4682 } 4683 4684 if (!Invalid) { 4685 // If this is a use, just return the declaration we found. 4686 4687 // FIXME: In the future, return a variant or some other clue 4688 // for the consumer of this Decl to know it doesn't own it. 4689 // For our current ASTs this shouldn't be a problem, but will 4690 // need to be changed with DeclGroups. 4691 if (TUK == TUK_Reference || TUK == TUK_Friend) 4692 return DeclPtrTy::make(PrevTagDecl); 4693 4694 // Diagnose attempts to redefine a tag. 4695 if (TUK == TUK_Definition) { 4696 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4697 // If we're defining a specialization and the previous definition 4698 // is from an implicit instantiation, don't emit an error 4699 // here; we'll catch this in the general case below. 4700 if (!isExplicitSpecialization || 4701 !isa<CXXRecordDecl>(Def) || 4702 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4703 == TSK_ExplicitSpecialization) { 4704 Diag(NameLoc, diag::err_redefinition) << Name; 4705 Diag(Def->getLocation(), diag::note_previous_definition); 4706 // If this is a redefinition, recover by making this 4707 // struct be anonymous, which will make any later 4708 // references get the previous definition. 4709 Name = 0; 4710 Previous.clear(); 4711 Invalid = true; 4712 } 4713 } else { 4714 // If the type is currently being defined, complain 4715 // about a nested redefinition. 4716 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4717 if (Tag->isBeingDefined()) { 4718 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4719 Diag(PrevTagDecl->getLocation(), 4720 diag::note_previous_definition); 4721 Name = 0; 4722 Previous.clear(); 4723 Invalid = true; 4724 } 4725 } 4726 4727 // Okay, this is definition of a previously declared or referenced 4728 // tag PrevDecl. We're going to create a new Decl for it. 4729 } 4730 } 4731 // If we get here we have (another) forward declaration or we 4732 // have a definition. Just create a new decl. 4733 4734 } else { 4735 // If we get here, this is a definition of a new tag type in a nested 4736 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4737 // new decl/type. We set PrevDecl to NULL so that the entities 4738 // have distinct types. 4739 Previous.clear(); 4740 } 4741 // If we get here, we're going to create a new Decl. If PrevDecl 4742 // is non-NULL, it's a definition of the tag declared by 4743 // PrevDecl. If it's NULL, we have a new definition. 4744 } else { 4745 // PrevDecl is a namespace, template, or anything else 4746 // that lives in the IDNS_Tag identifier namespace. 4747 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4748 // The tag name clashes with a namespace name, issue an error and 4749 // recover by making this tag be anonymous. 4750 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4751 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4752 Name = 0; 4753 Previous.clear(); 4754 Invalid = true; 4755 } else { 4756 // The existing declaration isn't relevant to us; we're in a 4757 // new scope, so clear out the previous declaration. 4758 Previous.clear(); 4759 } 4760 } 4761 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4762 // C++ [basic.scope.pdecl]p5: 4763 // -- for an elaborated-type-specifier of the form 4764 // 4765 // class-key identifier 4766 // 4767 // if the elaborated-type-specifier is used in the 4768 // decl-specifier-seq or parameter-declaration-clause of a 4769 // function defined in namespace scope, the identifier is 4770 // declared as a class-name in the namespace that contains 4771 // the declaration; otherwise, except as a friend 4772 // declaration, the identifier is declared in the smallest 4773 // non-class, non-function-prototype scope that contains the 4774 // declaration. 4775 // 4776 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4777 // C structs and unions. 4778 // 4779 // It is an error in C++ to declare (rather than define) an enum 4780 // type, including via an elaborated type specifier. We'll 4781 // diagnose that later; for now, declare the enum in the same 4782 // scope as we would have picked for any other tag type. 4783 // 4784 // GNU C also supports this behavior as part of its incomplete 4785 // enum types extension, while GNU C++ does not. 4786 // 4787 // Find the context where we'll be declaring the tag. 4788 // FIXME: We would like to maintain the current DeclContext as the 4789 // lexical context, 4790 while (SearchDC->isRecord()) 4791 SearchDC = SearchDC->getParent(); 4792 4793 // Find the scope where we'll be declaring the tag. 4794 while (S->isClassScope() || 4795 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4796 ((S->getFlags() & Scope::DeclScope) == 0) || 4797 (S->getEntity() && 4798 ((DeclContext *)S->getEntity())->isTransparentContext())) 4799 S = S->getParent(); 4800 4801 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4802 // C++ [namespace.memdef]p3: 4803 // If a friend declaration in a non-local class first declares a 4804 // class or function, the friend class or function is a member of 4805 // the innermost enclosing namespace. 4806 while (!SearchDC->isFileContext()) 4807 SearchDC = SearchDC->getParent(); 4808 4809 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4810 while (S->getEntity() != SearchDC) 4811 S = S->getParent(); 4812 } 4813 4814CreateNewDecl: 4815 4816 TagDecl *PrevDecl = 0; 4817 if (Previous.isSingleResult()) 4818 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4819 4820 // If there is an identifier, use the location of the identifier as the 4821 // location of the decl, otherwise use the location of the struct/union 4822 // keyword. 4823 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4824 4825 // Otherwise, create a new declaration. If there is a previous 4826 // declaration of the same entity, the two will be linked via 4827 // PrevDecl. 4828 TagDecl *New; 4829 4830 if (Kind == TagDecl::TK_enum) { 4831 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4832 // enum X { A, B, C } D; D should chain to X. 4833 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4834 cast_or_null<EnumDecl>(PrevDecl)); 4835 // If this is an undefined enum, warn. 4836 if (TUK != TUK_Definition && !Invalid) { 4837 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4838 : diag::ext_forward_ref_enum; 4839 Diag(Loc, DK); 4840 } 4841 } else { 4842 // struct/union/class 4843 4844 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4845 // struct X { int A; } D; D should chain to X. 4846 if (getLangOptions().CPlusPlus) { 4847 // FIXME: Look for a way to use RecordDecl for simple structs. 4848 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4849 cast_or_null<CXXRecordDecl>(PrevDecl)); 4850 4851 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4852 StdBadAlloc = cast<CXXRecordDecl>(New); 4853 } else 4854 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4855 cast_or_null<RecordDecl>(PrevDecl)); 4856 } 4857 4858 if (Kind != TagDecl::TK_enum) { 4859 // Handle #pragma pack: if the #pragma pack stack has non-default 4860 // alignment, make up a packed attribute for this decl. These 4861 // attributes are checked when the ASTContext lays out the 4862 // structure. 4863 // 4864 // It is important for implementing the correct semantics that this 4865 // happen here (in act on tag decl). The #pragma pack stack is 4866 // maintained as a result of parser callbacks which can occur at 4867 // many points during the parsing of a struct declaration (because 4868 // the #pragma tokens are effectively skipped over during the 4869 // parsing of the struct). 4870 if (unsigned Alignment = getPragmaPackAlignment()) 4871 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4872 } 4873 4874 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4875 // C++ [dcl.typedef]p3: 4876 // [...] Similarly, in a given scope, a class or enumeration 4877 // shall not be declared with the same name as a typedef-name 4878 // that is declared in that scope and refers to a type other 4879 // than the class or enumeration itself. 4880 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4881 ForRedeclaration); 4882 LookupName(Lookup, S); 4883 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4884 NamedDecl *PrevTypedefNamed = PrevTypedef; 4885 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4886 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4887 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4888 Diag(Loc, diag::err_tag_definition_of_typedef) 4889 << Context.getTypeDeclType(New) 4890 << PrevTypedef->getUnderlyingType(); 4891 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4892 Invalid = true; 4893 } 4894 } 4895 4896 // If this is a specialization of a member class (of a class template), 4897 // check the specialization. 4898 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4899 Invalid = true; 4900 4901 if (Invalid) 4902 New->setInvalidDecl(); 4903 4904 if (Attr) 4905 ProcessDeclAttributeList(S, New, Attr); 4906 4907 // If we're declaring or defining a tag in function prototype scope 4908 // in C, note that this type can only be used within the function. 4909 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4910 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4911 4912 // Set the lexical context. If the tag has a C++ scope specifier, the 4913 // lexical context will be different from the semantic context. 4914 New->setLexicalDeclContext(CurContext); 4915 4916 // Mark this as a friend decl if applicable. 4917 if (TUK == TUK_Friend) 4918 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4919 4920 // Set the access specifier. 4921 if (!Invalid && TUK != TUK_Friend) 4922 SetMemberAccessSpecifier(New, PrevDecl, AS); 4923 4924 if (TUK == TUK_Definition) 4925 New->startDefinition(); 4926 4927 // If this has an identifier, add it to the scope stack. 4928 if (TUK == TUK_Friend) { 4929 // We might be replacing an existing declaration in the lookup tables; 4930 // if so, borrow its access specifier. 4931 if (PrevDecl) 4932 New->setAccess(PrevDecl->getAccess()); 4933 4934 // Friend tag decls are visible in fairly strange ways. 4935 if (!CurContext->isDependentContext()) { 4936 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4937 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4938 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4939 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4940 } 4941 } else if (Name) { 4942 S = getNonFieldDeclScope(S); 4943 PushOnScopeChains(New, S); 4944 } else { 4945 CurContext->addDecl(New); 4946 } 4947 4948 // If this is the C FILE type, notify the AST context. 4949 if (IdentifierInfo *II = New->getIdentifier()) 4950 if (!New->isInvalidDecl() && 4951 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4952 II->isStr("FILE")) 4953 Context.setFILEDecl(New); 4954 4955 OwnedDecl = true; 4956 return DeclPtrTy::make(New); 4957} 4958 4959void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4960 AdjustDeclIfTemplate(TagD); 4961 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4962 4963 // Enter the tag context. 4964 PushDeclContext(S, Tag); 4965 4966 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4967 FieldCollector->StartClass(); 4968 4969 if (Record->getIdentifier()) { 4970 // C++ [class]p2: 4971 // [...] The class-name is also inserted into the scope of the 4972 // class itself; this is known as the injected-class-name. For 4973 // purposes of access checking, the injected-class-name is treated 4974 // as if it were a public member name. 4975 CXXRecordDecl *InjectedClassName 4976 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4977 CurContext, Record->getLocation(), 4978 Record->getIdentifier(), 4979 Record->getTagKeywordLoc(), 4980 Record); 4981 InjectedClassName->setImplicit(); 4982 InjectedClassName->setAccess(AS_public); 4983 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4984 InjectedClassName->setDescribedClassTemplate(Template); 4985 PushOnScopeChains(InjectedClassName, S); 4986 assert(InjectedClassName->isInjectedClassName() && 4987 "Broken injected-class-name"); 4988 } 4989 } 4990} 4991 4992void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4993 SourceLocation RBraceLoc) { 4994 AdjustDeclIfTemplate(TagD); 4995 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4996 Tag->setRBraceLoc(RBraceLoc); 4997 4998 if (isa<CXXRecordDecl>(Tag)) 4999 FieldCollector->FinishClass(); 5000 5001 // Exit this scope of this tag's definition. 5002 PopDeclContext(); 5003 5004 // Notify the consumer that we've defined a tag. 5005 Consumer.HandleTagDeclDefinition(Tag); 5006} 5007 5008// Note that FieldName may be null for anonymous bitfields. 5009bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5010 QualType FieldTy, const Expr *BitWidth, 5011 bool *ZeroWidth) { 5012 // Default to true; that shouldn't confuse checks for emptiness 5013 if (ZeroWidth) 5014 *ZeroWidth = true; 5015 5016 // C99 6.7.2.1p4 - verify the field type. 5017 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5018 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5019 // Handle incomplete types with specific error. 5020 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5021 return true; 5022 if (FieldName) 5023 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5024 << FieldName << FieldTy << BitWidth->getSourceRange(); 5025 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5026 << FieldTy << BitWidth->getSourceRange(); 5027 } 5028 5029 // If the bit-width is type- or value-dependent, don't try to check 5030 // it now. 5031 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5032 return false; 5033 5034 llvm::APSInt Value; 5035 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5036 return true; 5037 5038 if (Value != 0 && ZeroWidth) 5039 *ZeroWidth = false; 5040 5041 // Zero-width bitfield is ok for anonymous field. 5042 if (Value == 0 && FieldName) 5043 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5044 5045 if (Value.isSigned() && Value.isNegative()) { 5046 if (FieldName) 5047 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5048 << FieldName << Value.toString(10); 5049 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5050 << Value.toString(10); 5051 } 5052 5053 if (!FieldTy->isDependentType()) { 5054 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5055 if (Value.getZExtValue() > TypeSize) { 5056 if (FieldName) 5057 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5058 << FieldName << (unsigned)TypeSize; 5059 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5060 << (unsigned)TypeSize; 5061 } 5062 } 5063 5064 return false; 5065} 5066 5067/// ActOnField - Each field of a struct/union/class is passed into this in order 5068/// to create a FieldDecl object for it. 5069Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5070 SourceLocation DeclStart, 5071 Declarator &D, ExprTy *BitfieldWidth) { 5072 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5073 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5074 AS_public); 5075 return DeclPtrTy::make(Res); 5076} 5077 5078/// HandleField - Analyze a field of a C struct or a C++ data member. 5079/// 5080FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5081 SourceLocation DeclStart, 5082 Declarator &D, Expr *BitWidth, 5083 AccessSpecifier AS) { 5084 IdentifierInfo *II = D.getIdentifier(); 5085 SourceLocation Loc = DeclStart; 5086 if (II) Loc = D.getIdentifierLoc(); 5087 5088 TypeSourceInfo *TInfo = 0; 5089 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5090 if (getLangOptions().CPlusPlus) 5091 CheckExtraCXXDefaultArguments(D); 5092 5093 DiagnoseFunctionSpecifiers(D); 5094 5095 if (D.getDeclSpec().isThreadSpecified()) 5096 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5097 5098 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5099 ForRedeclaration); 5100 5101 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5102 // Maybe we will complain about the shadowed template parameter. 5103 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5104 // Just pretend that we didn't see the previous declaration. 5105 PrevDecl = 0; 5106 } 5107 5108 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5109 PrevDecl = 0; 5110 5111 bool Mutable 5112 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5113 SourceLocation TSSL = D.getSourceRange().getBegin(); 5114 FieldDecl *NewFD 5115 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5116 AS, PrevDecl, &D); 5117 if (NewFD->isInvalidDecl() && PrevDecl) { 5118 // Don't introduce NewFD into scope; there's already something 5119 // with the same name in the same scope. 5120 } else if (II) { 5121 PushOnScopeChains(NewFD, S); 5122 } else 5123 Record->addDecl(NewFD); 5124 5125 return NewFD; 5126} 5127 5128/// \brief Build a new FieldDecl and check its well-formedness. 5129/// 5130/// This routine builds a new FieldDecl given the fields name, type, 5131/// record, etc. \p PrevDecl should refer to any previous declaration 5132/// with the same name and in the same scope as the field to be 5133/// created. 5134/// 5135/// \returns a new FieldDecl. 5136/// 5137/// \todo The Declarator argument is a hack. It will be removed once 5138FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5139 TypeSourceInfo *TInfo, 5140 RecordDecl *Record, SourceLocation Loc, 5141 bool Mutable, Expr *BitWidth, 5142 SourceLocation TSSL, 5143 AccessSpecifier AS, NamedDecl *PrevDecl, 5144 Declarator *D) { 5145 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5146 bool InvalidDecl = false; 5147 if (D) InvalidDecl = D->isInvalidType(); 5148 5149 // If we receive a broken type, recover by assuming 'int' and 5150 // marking this declaration as invalid. 5151 if (T.isNull()) { 5152 InvalidDecl = true; 5153 T = Context.IntTy; 5154 } 5155 5156 QualType EltTy = Context.getBaseElementType(T); 5157 if (!EltTy->isDependentType() && 5158 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5159 InvalidDecl = true; 5160 5161 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5162 // than a variably modified type. 5163 if (!InvalidDecl && T->isVariablyModifiedType()) { 5164 bool SizeIsNegative; 5165 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5166 SizeIsNegative); 5167 if (!FixedTy.isNull()) { 5168 Diag(Loc, diag::warn_illegal_constant_array_size); 5169 T = FixedTy; 5170 } else { 5171 if (SizeIsNegative) 5172 Diag(Loc, diag::err_typecheck_negative_array_size); 5173 else 5174 Diag(Loc, diag::err_typecheck_field_variable_size); 5175 InvalidDecl = true; 5176 } 5177 } 5178 5179 // Fields can not have abstract class types 5180 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5181 diag::err_abstract_type_in_decl, 5182 AbstractFieldType)) 5183 InvalidDecl = true; 5184 5185 bool ZeroWidth = false; 5186 // If this is declared as a bit-field, check the bit-field. 5187 if (!InvalidDecl && BitWidth && 5188 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5189 InvalidDecl = true; 5190 DeleteExpr(BitWidth); 5191 BitWidth = 0; 5192 ZeroWidth = false; 5193 } 5194 5195 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5196 BitWidth, Mutable); 5197 if (InvalidDecl) 5198 NewFD->setInvalidDecl(); 5199 5200 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5201 Diag(Loc, diag::err_duplicate_member) << II; 5202 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5203 NewFD->setInvalidDecl(); 5204 } 5205 5206 if (getLangOptions().CPlusPlus) { 5207 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5208 5209 if (!T->isPODType()) 5210 CXXRecord->setPOD(false); 5211 if (!ZeroWidth) 5212 CXXRecord->setEmpty(false); 5213 5214 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5215 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5216 5217 if (!RDecl->hasTrivialConstructor()) 5218 CXXRecord->setHasTrivialConstructor(false); 5219 if (!RDecl->hasTrivialCopyConstructor()) 5220 CXXRecord->setHasTrivialCopyConstructor(false); 5221 if (!RDecl->hasTrivialCopyAssignment()) 5222 CXXRecord->setHasTrivialCopyAssignment(false); 5223 if (!RDecl->hasTrivialDestructor()) 5224 CXXRecord->setHasTrivialDestructor(false); 5225 5226 // C++ 9.5p1: An object of a class with a non-trivial 5227 // constructor, a non-trivial copy constructor, a non-trivial 5228 // destructor, or a non-trivial copy assignment operator 5229 // cannot be a member of a union, nor can an array of such 5230 // objects. 5231 // TODO: C++0x alters this restriction significantly. 5232 if (Record->isUnion()) { 5233 // We check for copy constructors before constructors 5234 // because otherwise we'll never get complaints about 5235 // copy constructors. 5236 5237 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5238 5239 CXXSpecialMember member; 5240 if (!RDecl->hasTrivialCopyConstructor()) 5241 member = CXXCopyConstructor; 5242 else if (!RDecl->hasTrivialConstructor()) 5243 member = CXXDefaultConstructor; 5244 else if (!RDecl->hasTrivialCopyAssignment()) 5245 member = CXXCopyAssignment; 5246 else if (!RDecl->hasTrivialDestructor()) 5247 member = CXXDestructor; 5248 else 5249 member = invalid; 5250 5251 if (member != invalid) { 5252 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5253 DiagnoseNontrivial(RT, member); 5254 NewFD->setInvalidDecl(); 5255 } 5256 } 5257 } 5258 } 5259 5260 // FIXME: We need to pass in the attributes given an AST 5261 // representation, not a parser representation. 5262 if (D) 5263 // FIXME: What to pass instead of TUScope? 5264 ProcessDeclAttributes(TUScope, NewFD, *D); 5265 5266 if (T.isObjCGCWeak()) 5267 Diag(Loc, diag::warn_attribute_weak_on_field); 5268 5269 NewFD->setAccess(AS); 5270 5271 // C++ [dcl.init.aggr]p1: 5272 // An aggregate is an array or a class (clause 9) with [...] no 5273 // private or protected non-static data members (clause 11). 5274 // A POD must be an aggregate. 5275 if (getLangOptions().CPlusPlus && 5276 (AS == AS_private || AS == AS_protected)) { 5277 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5278 CXXRecord->setAggregate(false); 5279 CXXRecord->setPOD(false); 5280 } 5281 5282 return NewFD; 5283} 5284 5285/// DiagnoseNontrivial - Given that a class has a non-trivial 5286/// special member, figure out why. 5287void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5288 QualType QT(T, 0U); 5289 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5290 5291 // Check whether the member was user-declared. 5292 switch (member) { 5293 case CXXDefaultConstructor: 5294 if (RD->hasUserDeclaredConstructor()) { 5295 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5296 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5297 const FunctionDecl *body = 0; 5298 ci->getBody(body); 5299 if (!body || 5300 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5301 SourceLocation CtorLoc = ci->getLocation(); 5302 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5303 return; 5304 } 5305 } 5306 5307 assert(0 && "found no user-declared constructors"); 5308 return; 5309 } 5310 break; 5311 5312 case CXXCopyConstructor: 5313 if (RD->hasUserDeclaredCopyConstructor()) { 5314 SourceLocation CtorLoc = 5315 RD->getCopyConstructor(Context, 0)->getLocation(); 5316 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5317 return; 5318 } 5319 break; 5320 5321 case CXXCopyAssignment: 5322 if (RD->hasUserDeclaredCopyAssignment()) { 5323 // FIXME: this should use the location of the copy 5324 // assignment, not the type. 5325 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5326 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5327 return; 5328 } 5329 break; 5330 5331 case CXXDestructor: 5332 if (RD->hasUserDeclaredDestructor()) { 5333 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5334 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5335 return; 5336 } 5337 break; 5338 } 5339 5340 typedef CXXRecordDecl::base_class_iterator base_iter; 5341 5342 // Virtual bases and members inhibit trivial copying/construction, 5343 // but not trivial destruction. 5344 if (member != CXXDestructor) { 5345 // Check for virtual bases. vbases includes indirect virtual bases, 5346 // so we just iterate through the direct bases. 5347 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5348 if (bi->isVirtual()) { 5349 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5350 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5351 return; 5352 } 5353 5354 // Check for virtual methods. 5355 typedef CXXRecordDecl::method_iterator meth_iter; 5356 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5357 ++mi) { 5358 if (mi->isVirtual()) { 5359 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5360 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5361 return; 5362 } 5363 } 5364 } 5365 5366 bool (CXXRecordDecl::*hasTrivial)() const; 5367 switch (member) { 5368 case CXXDefaultConstructor: 5369 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5370 case CXXCopyConstructor: 5371 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5372 case CXXCopyAssignment: 5373 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5374 case CXXDestructor: 5375 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5376 default: 5377 assert(0 && "unexpected special member"); return; 5378 } 5379 5380 // Check for nontrivial bases (and recurse). 5381 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5382 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5383 assert(BaseRT && "Don't know how to handle dependent bases"); 5384 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5385 if (!(BaseRecTy->*hasTrivial)()) { 5386 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5387 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5388 DiagnoseNontrivial(BaseRT, member); 5389 return; 5390 } 5391 } 5392 5393 // Check for nontrivial members (and recurse). 5394 typedef RecordDecl::field_iterator field_iter; 5395 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5396 ++fi) { 5397 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5398 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5399 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5400 5401 if (!(EltRD->*hasTrivial)()) { 5402 SourceLocation FLoc = (*fi)->getLocation(); 5403 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5404 DiagnoseNontrivial(EltRT, member); 5405 return; 5406 } 5407 } 5408 } 5409 5410 assert(0 && "found no explanation for non-trivial member"); 5411} 5412 5413/// TranslateIvarVisibility - Translate visibility from a token ID to an 5414/// AST enum value. 5415static ObjCIvarDecl::AccessControl 5416TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5417 switch (ivarVisibility) { 5418 default: assert(0 && "Unknown visitibility kind"); 5419 case tok::objc_private: return ObjCIvarDecl::Private; 5420 case tok::objc_public: return ObjCIvarDecl::Public; 5421 case tok::objc_protected: return ObjCIvarDecl::Protected; 5422 case tok::objc_package: return ObjCIvarDecl::Package; 5423 } 5424} 5425 5426/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5427/// in order to create an IvarDecl object for it. 5428Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5429 SourceLocation DeclStart, 5430 DeclPtrTy IntfDecl, 5431 Declarator &D, ExprTy *BitfieldWidth, 5432 tok::ObjCKeywordKind Visibility) { 5433 5434 IdentifierInfo *II = D.getIdentifier(); 5435 Expr *BitWidth = (Expr*)BitfieldWidth; 5436 SourceLocation Loc = DeclStart; 5437 if (II) Loc = D.getIdentifierLoc(); 5438 5439 // FIXME: Unnamed fields can be handled in various different ways, for 5440 // example, unnamed unions inject all members into the struct namespace! 5441 5442 TypeSourceInfo *TInfo = 0; 5443 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5444 5445 if (BitWidth) { 5446 // 6.7.2.1p3, 6.7.2.1p4 5447 if (VerifyBitField(Loc, II, T, BitWidth)) { 5448 D.setInvalidType(); 5449 DeleteExpr(BitWidth); 5450 BitWidth = 0; 5451 } 5452 } else { 5453 // Not a bitfield. 5454 5455 // validate II. 5456 5457 } 5458 5459 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5460 // than a variably modified type. 5461 if (T->isVariablyModifiedType()) { 5462 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5463 D.setInvalidType(); 5464 } 5465 5466 // Get the visibility (access control) for this ivar. 5467 ObjCIvarDecl::AccessControl ac = 5468 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5469 : ObjCIvarDecl::None; 5470 // Must set ivar's DeclContext to its enclosing interface. 5471 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5472 DeclContext *EnclosingContext; 5473 if (ObjCImplementationDecl *IMPDecl = 5474 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5475 // Case of ivar declared in an implementation. Context is that of its class. 5476 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5477 assert(IDecl && "No class- ActOnIvar"); 5478 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5479 } else 5480 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5481 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5482 5483 // Construct the decl. 5484 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5485 EnclosingContext, Loc, II, T, 5486 TInfo, ac, (Expr *)BitfieldWidth); 5487 5488 if (II) { 5489 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5490 ForRedeclaration); 5491 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5492 && !isa<TagDecl>(PrevDecl)) { 5493 Diag(Loc, diag::err_duplicate_member) << II; 5494 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5495 NewID->setInvalidDecl(); 5496 } 5497 } 5498 5499 // Process attributes attached to the ivar. 5500 ProcessDeclAttributes(S, NewID, D); 5501 5502 if (D.isInvalidType()) 5503 NewID->setInvalidDecl(); 5504 5505 if (II) { 5506 // FIXME: When interfaces are DeclContexts, we'll need to add 5507 // these to the interface. 5508 S->AddDecl(DeclPtrTy::make(NewID)); 5509 IdResolver.AddDecl(NewID); 5510 } 5511 5512 return DeclPtrTy::make(NewID); 5513} 5514 5515void Sema::ActOnFields(Scope* S, 5516 SourceLocation RecLoc, DeclPtrTy RecDecl, 5517 DeclPtrTy *Fields, unsigned NumFields, 5518 SourceLocation LBrac, SourceLocation RBrac, 5519 AttributeList *Attr) { 5520 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5521 assert(EnclosingDecl && "missing record or interface decl"); 5522 5523 // If the decl this is being inserted into is invalid, then it may be a 5524 // redeclaration or some other bogus case. Don't try to add fields to it. 5525 if (EnclosingDecl->isInvalidDecl()) { 5526 // FIXME: Deallocate fields? 5527 return; 5528 } 5529 5530 5531 // Verify that all the fields are okay. 5532 unsigned NumNamedMembers = 0; 5533 llvm::SmallVector<FieldDecl*, 32> RecFields; 5534 5535 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5536 for (unsigned i = 0; i != NumFields; ++i) { 5537 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5538 5539 // Get the type for the field. 5540 Type *FDTy = FD->getType().getTypePtr(); 5541 5542 if (!FD->isAnonymousStructOrUnion()) { 5543 // Remember all fields written by the user. 5544 RecFields.push_back(FD); 5545 } 5546 5547 // If the field is already invalid for some reason, don't emit more 5548 // diagnostics about it. 5549 if (FD->isInvalidDecl()) { 5550 EnclosingDecl->setInvalidDecl(); 5551 continue; 5552 } 5553 5554 // C99 6.7.2.1p2: 5555 // A structure or union shall not contain a member with 5556 // incomplete or function type (hence, a structure shall not 5557 // contain an instance of itself, but may contain a pointer to 5558 // an instance of itself), except that the last member of a 5559 // structure with more than one named member may have incomplete 5560 // array type; such a structure (and any union containing, 5561 // possibly recursively, a member that is such a structure) 5562 // shall not be a member of a structure or an element of an 5563 // array. 5564 if (FDTy->isFunctionType()) { 5565 // Field declared as a function. 5566 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5567 << FD->getDeclName(); 5568 FD->setInvalidDecl(); 5569 EnclosingDecl->setInvalidDecl(); 5570 continue; 5571 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5572 Record && Record->isStruct()) { 5573 // Flexible array member. 5574 if (NumNamedMembers < 1) { 5575 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5576 << FD->getDeclName(); 5577 FD->setInvalidDecl(); 5578 EnclosingDecl->setInvalidDecl(); 5579 continue; 5580 } 5581 // Okay, we have a legal flexible array member at the end of the struct. 5582 if (Record) 5583 Record->setHasFlexibleArrayMember(true); 5584 } else if (!FDTy->isDependentType() && 5585 RequireCompleteType(FD->getLocation(), FD->getType(), 5586 diag::err_field_incomplete)) { 5587 // Incomplete type 5588 FD->setInvalidDecl(); 5589 EnclosingDecl->setInvalidDecl(); 5590 continue; 5591 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5592 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5593 // If this is a member of a union, then entire union becomes "flexible". 5594 if (Record && Record->isUnion()) { 5595 Record->setHasFlexibleArrayMember(true); 5596 } else { 5597 // If this is a struct/class and this is not the last element, reject 5598 // it. Note that GCC supports variable sized arrays in the middle of 5599 // structures. 5600 if (i != NumFields-1) 5601 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5602 << FD->getDeclName() << FD->getType(); 5603 else { 5604 // We support flexible arrays at the end of structs in 5605 // other structs as an extension. 5606 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5607 << FD->getDeclName(); 5608 if (Record) 5609 Record->setHasFlexibleArrayMember(true); 5610 } 5611 } 5612 } 5613 if (Record && FDTTy->getDecl()->hasObjectMember()) 5614 Record->setHasObjectMember(true); 5615 } else if (FDTy->isObjCInterfaceType()) { 5616 /// A field cannot be an Objective-c object 5617 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5618 FD->setInvalidDecl(); 5619 EnclosingDecl->setInvalidDecl(); 5620 continue; 5621 } else if (getLangOptions().ObjC1 && 5622 getLangOptions().getGCMode() != LangOptions::NonGC && 5623 Record && 5624 (FD->getType()->isObjCObjectPointerType() || 5625 FD->getType().isObjCGCStrong())) 5626 Record->setHasObjectMember(true); 5627 // Keep track of the number of named members. 5628 if (FD->getIdentifier()) 5629 ++NumNamedMembers; 5630 } 5631 5632 // Okay, we successfully defined 'Record'. 5633 if (Record) { 5634 Record->completeDefinition(Context); 5635 } else { 5636 ObjCIvarDecl **ClsFields = 5637 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5638 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5639 ID->setIVarList(ClsFields, RecFields.size(), Context); 5640 ID->setLocEnd(RBrac); 5641 // Add ivar's to class's DeclContext. 5642 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5643 ClsFields[i]->setLexicalDeclContext(ID); 5644 ID->addDecl(ClsFields[i]); 5645 } 5646 // Must enforce the rule that ivars in the base classes may not be 5647 // duplicates. 5648 if (ID->getSuperClass()) { 5649 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5650 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5651 ObjCIvarDecl* Ivar = (*IVI); 5652 5653 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5654 ObjCIvarDecl* prevIvar = 5655 ID->getSuperClass()->lookupInstanceVariable(II); 5656 if (prevIvar) { 5657 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5658 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5659 } 5660 } 5661 } 5662 } 5663 } else if (ObjCImplementationDecl *IMPDecl = 5664 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5665 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5666 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5667 // Ivar declared in @implementation never belongs to the implementation. 5668 // Only it is in implementation's lexical context. 5669 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5670 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5671 } 5672 } 5673 5674 if (Attr) 5675 ProcessDeclAttributeList(S, Record, Attr); 5676} 5677 5678EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5679 EnumConstantDecl *LastEnumConst, 5680 SourceLocation IdLoc, 5681 IdentifierInfo *Id, 5682 ExprArg val) { 5683 Expr *Val = (Expr *)val.get(); 5684 5685 llvm::APSInt EnumVal(32); 5686 QualType EltTy; 5687 if (Val) { 5688 if (Enum->isDependentType()) 5689 EltTy = Context.DependentTy; 5690 else { 5691 // Make sure to promote the operand type to int. 5692 UsualUnaryConversions(Val); 5693 if (Val != val.get()) { 5694 val.release(); 5695 val = Val; 5696 } 5697 5698 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5699 SourceLocation ExpLoc; 5700 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 5701 Val = 0; 5702 } else { 5703 EltTy = Val->getType(); 5704 } 5705 } 5706 } 5707 5708 if (!Val) { 5709 if (Enum->isDependentType()) 5710 EltTy = Context.DependentTy; 5711 else if (LastEnumConst) { 5712 // Assign the last value + 1. 5713 EnumVal = LastEnumConst->getInitVal(); 5714 ++EnumVal; 5715 5716 // Check for overflow on increment. 5717 if (EnumVal < LastEnumConst->getInitVal()) 5718 Diag(IdLoc, diag::warn_enum_value_overflow); 5719 5720 EltTy = LastEnumConst->getType(); 5721 } else { 5722 // First value, set to zero. 5723 EltTy = Context.IntTy; 5724 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5725 EnumVal.setIsSigned(true); 5726 } 5727 } 5728 5729 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5730 5731 val.release(); 5732 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5733 Val, EnumVal); 5734} 5735 5736 5737Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5738 DeclPtrTy lastEnumConst, 5739 SourceLocation IdLoc, 5740 IdentifierInfo *Id, 5741 SourceLocation EqualLoc, ExprTy *val) { 5742 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5743 EnumConstantDecl *LastEnumConst = 5744 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5745 Expr *Val = static_cast<Expr*>(val); 5746 5747 // The scope passed in may not be a decl scope. Zip up the scope tree until 5748 // we find one that is. 5749 S = getNonFieldDeclScope(S); 5750 5751 // Verify that there isn't already something declared with this name in this 5752 // scope. 5753 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5754 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5755 // Maybe we will complain about the shadowed template parameter. 5756 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5757 // Just pretend that we didn't see the previous declaration. 5758 PrevDecl = 0; 5759 } 5760 5761 if (PrevDecl) { 5762 // When in C++, we may get a TagDecl with the same name; in this case the 5763 // enum constant will 'hide' the tag. 5764 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5765 "Received TagDecl when not in C++!"); 5766 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5767 if (isa<EnumConstantDecl>(PrevDecl)) 5768 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5769 else 5770 Diag(IdLoc, diag::err_redefinition) << Id; 5771 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5772 if (Val) Val->Destroy(Context); 5773 return DeclPtrTy(); 5774 } 5775 } 5776 5777 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5778 IdLoc, Id, Owned(Val)); 5779 5780 // Register this decl in the current scope stack. 5781 if (New) 5782 PushOnScopeChains(New, S); 5783 5784 return DeclPtrTy::make(New); 5785} 5786 5787void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5788 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5789 DeclPtrTy *Elements, unsigned NumElements, 5790 Scope *S, AttributeList *Attr) { 5791 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5792 QualType EnumType = Context.getTypeDeclType(Enum); 5793 5794 if (Attr) 5795 ProcessDeclAttributeList(S, Enum, Attr); 5796 5797 if (Enum->isDependentType()) { 5798 for (unsigned i = 0; i != NumElements; ++i) { 5799 EnumConstantDecl *ECD = 5800 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5801 if (!ECD) continue; 5802 5803 ECD->setType(EnumType); 5804 } 5805 5806 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 5807 return; 5808 } 5809 5810 // TODO: If the result value doesn't fit in an int, it must be a long or long 5811 // long value. ISO C does not support this, but GCC does as an extension, 5812 // emit a warning. 5813 unsigned IntWidth = Context.Target.getIntWidth(); 5814 unsigned CharWidth = Context.Target.getCharWidth(); 5815 unsigned ShortWidth = Context.Target.getShortWidth(); 5816 5817 // Verify that all the values are okay, compute the size of the values, and 5818 // reverse the list. 5819 unsigned NumNegativeBits = 0; 5820 unsigned NumPositiveBits = 0; 5821 5822 // Keep track of whether all elements have type int. 5823 bool AllElementsInt = true; 5824 5825 for (unsigned i = 0; i != NumElements; ++i) { 5826 EnumConstantDecl *ECD = 5827 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5828 if (!ECD) continue; // Already issued a diagnostic. 5829 5830 // If the enum value doesn't fit in an int, emit an extension warning. 5831 const llvm::APSInt &InitVal = ECD->getInitVal(); 5832 assert(InitVal.getBitWidth() >= IntWidth && 5833 "Should have promoted value to int"); 5834 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 5835 llvm::APSInt V(InitVal); 5836 V.trunc(IntWidth); 5837 V.extend(InitVal.getBitWidth()); 5838 if (V != InitVal) 5839 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5840 << InitVal.toString(10); 5841 } 5842 5843 // Keep track of the size of positive and negative values. 5844 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5845 NumPositiveBits = std::max(NumPositiveBits, 5846 (unsigned)InitVal.getActiveBits()); 5847 else 5848 NumNegativeBits = std::max(NumNegativeBits, 5849 (unsigned)InitVal.getMinSignedBits()); 5850 5851 // Keep track of whether every enum element has type int (very commmon). 5852 if (AllElementsInt) 5853 AllElementsInt = ECD->getType() == Context.IntTy; 5854 } 5855 5856 // Figure out the type that should be used for this enum. 5857 // FIXME: Support -fshort-enums. 5858 QualType BestType; 5859 unsigned BestWidth; 5860 5861 // C++0x N3000 [conv.prom]p3: 5862 // An rvalue of an unscoped enumeration type whose underlying 5863 // type is not fixed can be converted to an rvalue of the first 5864 // of the following types that can represent all the values of 5865 // the enumeration: int, unsigned int, long int, unsigned long 5866 // int, long long int, or unsigned long long int. 5867 // C99 6.4.4.3p2: 5868 // An identifier declared as an enumeration constant has type int. 5869 // The C99 rule is modified by a gcc extension 5870 QualType BestPromotionType; 5871 5872 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5873 5874 if (NumNegativeBits) { 5875 // If there is a negative value, figure out the smallest integer type (of 5876 // int/long/longlong) that fits. 5877 // If it's packed, check also if it fits a char or a short. 5878 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5879 BestType = Context.SignedCharTy; 5880 BestWidth = CharWidth; 5881 } else if (Packed && NumNegativeBits <= ShortWidth && 5882 NumPositiveBits < ShortWidth) { 5883 BestType = Context.ShortTy; 5884 BestWidth = ShortWidth; 5885 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5886 BestType = Context.IntTy; 5887 BestWidth = IntWidth; 5888 } else { 5889 BestWidth = Context.Target.getLongWidth(); 5890 5891 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5892 BestType = Context.LongTy; 5893 } else { 5894 BestWidth = Context.Target.getLongLongWidth(); 5895 5896 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5897 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5898 BestType = Context.LongLongTy; 5899 } 5900 } 5901 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5902 } else { 5903 // If there is no negative value, figure out which of uint, ulong, ulonglong 5904 // fits. 5905 // If it's packed, check also if it fits a char or a short. 5906 if (Packed && NumPositiveBits <= CharWidth) { 5907 BestType = Context.UnsignedCharTy; 5908 BestPromotionType = Context.IntTy; 5909 BestWidth = CharWidth; 5910 } else if (Packed && NumPositiveBits <= ShortWidth) { 5911 BestType = Context.UnsignedShortTy; 5912 BestPromotionType = Context.IntTy; 5913 BestWidth = ShortWidth; 5914 } else if (NumPositiveBits <= IntWidth) { 5915 BestType = Context.UnsignedIntTy; 5916 BestWidth = IntWidth; 5917 BestPromotionType = (NumPositiveBits == BestWidth 5918 ? Context.UnsignedIntTy : Context.IntTy); 5919 } else if (NumPositiveBits <= 5920 (BestWidth = Context.Target.getLongWidth())) { 5921 BestType = Context.UnsignedLongTy; 5922 BestPromotionType = (NumPositiveBits == BestWidth 5923 ? Context.UnsignedLongTy : Context.LongTy); 5924 } else { 5925 BestWidth = Context.Target.getLongLongWidth(); 5926 assert(NumPositiveBits <= BestWidth && 5927 "How could an initializer get larger than ULL?"); 5928 BestType = Context.UnsignedLongLongTy; 5929 BestPromotionType = (NumPositiveBits == BestWidth 5930 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5931 } 5932 } 5933 5934 // If we're in C and the promotion type is larger than an int, just 5935 // use the underlying type, which is generally the unsigned integer 5936 // type of the same rank as the promotion type. This is how the gcc 5937 // extension works. 5938 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5939 BestPromotionType = BestType; 5940 5941 // Loop over all of the enumerator constants, changing their types to match 5942 // the type of the enum if needed. 5943 for (unsigned i = 0; i != NumElements; ++i) { 5944 EnumConstantDecl *ECD = 5945 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5946 if (!ECD) continue; // Already issued a diagnostic. 5947 5948 // Standard C says the enumerators have int type, but we allow, as an 5949 // extension, the enumerators to be larger than int size. If each 5950 // enumerator value fits in an int, type it as an int, otherwise type it the 5951 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5952 // that X has type 'int', not 'unsigned'. 5953 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 5954 continue; 5955 5956 // Determine whether the value fits into an int. 5957 llvm::APSInt InitVal = ECD->getInitVal(); 5958 bool FitsInInt; 5959 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5960 FitsInInt = InitVal.getActiveBits() < IntWidth; 5961 else 5962 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5963 5964 // If it fits into an integer type, force it. Otherwise force it to match 5965 // the enum decl type. 5966 QualType NewTy; 5967 unsigned NewWidth; 5968 bool NewSign; 5969 if (FitsInInt && !getLangOptions().CPlusPlus) { 5970 NewTy = Context.IntTy; 5971 NewWidth = IntWidth; 5972 NewSign = true; 5973 } else if (ECD->getType() == BestType) { 5974 // Already the right type! 5975 if (getLangOptions().CPlusPlus) 5976 // C++ [dcl.enum]p4: Following the closing brace of an 5977 // enum-specifier, each enumerator has the type of its 5978 // enumeration. 5979 ECD->setType(EnumType); 5980 continue; 5981 } else { 5982 NewTy = BestType; 5983 NewWidth = BestWidth; 5984 NewSign = BestType->isSignedIntegerType(); 5985 } 5986 5987 // Adjust the APSInt value. 5988 InitVal.extOrTrunc(NewWidth); 5989 InitVal.setIsSigned(NewSign); 5990 ECD->setInitVal(InitVal); 5991 5992 // Adjust the Expr initializer and type. 5993 if (ECD->getInitExpr()) 5994 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5995 CastExpr::CK_IntegralCast, 5996 ECD->getInitExpr(), 5997 /*isLvalue=*/false)); 5998 if (getLangOptions().CPlusPlus) 5999 // C++ [dcl.enum]p4: Following the closing brace of an 6000 // enum-specifier, each enumerator has the type of its 6001 // enumeration. 6002 ECD->setType(EnumType); 6003 else 6004 ECD->setType(NewTy); 6005 } 6006 6007 Enum->completeDefinition(Context, BestType, BestPromotionType); 6008} 6009 6010Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6011 ExprArg expr) { 6012 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6013 6014 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6015 Loc, AsmString); 6016 CurContext->addDecl(New); 6017 return DeclPtrTy::make(New); 6018} 6019 6020void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6021 SourceLocation PragmaLoc, 6022 SourceLocation NameLoc) { 6023 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6024 6025 if (PrevDecl) { 6026 PrevDecl->addAttr(::new (Context) WeakAttr()); 6027 } else { 6028 (void)WeakUndeclaredIdentifiers.insert( 6029 std::pair<IdentifierInfo*,WeakInfo> 6030 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6031 } 6032} 6033 6034void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6035 IdentifierInfo* AliasName, 6036 SourceLocation PragmaLoc, 6037 SourceLocation NameLoc, 6038 SourceLocation AliasNameLoc) { 6039 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6040 WeakInfo W = WeakInfo(Name, NameLoc); 6041 6042 if (PrevDecl) { 6043 if (!PrevDecl->hasAttr<AliasAttr>()) 6044 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6045 DeclApplyPragmaWeak(TUScope, ND, W); 6046 } else { 6047 (void)WeakUndeclaredIdentifiers.insert( 6048 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6049 } 6050} 6051