SemaDecl.cpp revision 3f09327b26033d0a9676d52d80cf92c48f581aff
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Basic/PartialDiagnostic.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/Basic/TargetInfo.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/BitVector.h" 33#include "llvm/ADT/STLExtras.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37#include <queue> 38using namespace clang; 39 40/// getDeclName - Return a pretty name for the specified decl if possible, or 41/// an empty string if not. This is used for pretty crash reporting. 42std::string Sema::getDeclName(DeclPtrTy d) { 43 Decl *D = d.getAs<Decl>(); 44 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 45 return DN->getQualifiedNameAsString(); 46 return ""; 47} 48 49Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 50 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 51} 52 53/// \brief If the identifier refers to a type name within this scope, 54/// return the declaration of that type. 55/// 56/// This routine performs ordinary name lookup of the identifier II 57/// within the given scope, with optional C++ scope specifier SS, to 58/// determine whether the name refers to a type. If so, returns an 59/// opaque pointer (actually a QualType) corresponding to that 60/// type. Otherwise, returns NULL. 61/// 62/// If name lookup results in an ambiguity, this routine will complain 63/// and then return NULL. 64Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 65 Scope *S, const CXXScopeSpec *SS, 66 bool isClassName) { 67 // C++ [temp.res]p3: 68 // A qualified-id that refers to a type and in which the 69 // nested-name-specifier depends on a template-parameter (14.6.2) 70 // shall be prefixed by the keyword typename to indicate that the 71 // qualified-id denotes a type, forming an 72 // elaborated-type-specifier (7.1.5.3). 73 // 74 // We therefore do not perform any name lookup if the result would 75 // refer to a member of an unknown specialization. 76 if (SS && isUnknownSpecialization(*SS)) { 77 if (!isClassName) 78 return 0; 79 80 // We know from the grammar that this name refers to a type, so build a 81 // TypenameType node to describe the type. 82 // FIXME: Record somewhere that this TypenameType node has no "typename" 83 // keyword associated with it. 84 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 85 II, SS->getRange()).getAsOpaquePtr(); 86 } 87 88 LookupResult Result; 89 LookupParsedName(Result, S, SS, &II, LookupOrdinaryName, false, false); 90 91 NamedDecl *IIDecl = 0; 92 switch (Result.getKind()) { 93 case LookupResult::NotFound: 94 case LookupResult::FoundOverloaded: 95 return 0; 96 97 case LookupResult::Ambiguous: { 98 // Recover from type-hiding ambiguities by hiding the type. We'll 99 // do the lookup again when looking for an object, and we can 100 // diagnose the error then. If we don't do this, then the error 101 // about hiding the type will be immediately followed by an error 102 // that only makes sense if the identifier was treated like a type. 103 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) 104 return 0; 105 106 // Look to see if we have a type anywhere in the list of results. 107 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 108 Res != ResEnd; ++Res) { 109 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 110 if (!IIDecl || 111 (*Res)->getLocation().getRawEncoding() < 112 IIDecl->getLocation().getRawEncoding()) 113 IIDecl = *Res; 114 } 115 } 116 117 if (!IIDecl) { 118 // None of the entities we found is a type, so there is no way 119 // to even assume that the result is a type. In this case, don't 120 // complain about the ambiguity. The parser will either try to 121 // perform this lookup again (e.g., as an object name), which 122 // will produce the ambiguity, or will complain that it expected 123 // a type name. 124 return 0; 125 } 126 127 // We found a type within the ambiguous lookup; diagnose the 128 // ambiguity and then return that type. This might be the right 129 // answer, or it might not be, but it suppresses any attempt to 130 // perform the name lookup again. 131 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 132 break; 133 } 134 135 case LookupResult::Found: 136 IIDecl = Result.getFoundDecl(); 137 break; 138 } 139 140 if (IIDecl) { 141 QualType T; 142 143 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 144 // Check whether we can use this type 145 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 146 147 if (getLangOptions().CPlusPlus) { 148 // C++ [temp.local]p2: 149 // Within the scope of a class template specialization or 150 // partial specialization, when the injected-class-name is 151 // not followed by a <, it is equivalent to the 152 // injected-class-name followed by the template-argument s 153 // of the class template specialization or partial 154 // specialization enclosed in <>. 155 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 156 if (RD->isInjectedClassName()) 157 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 158 T = Template->getInjectedClassNameType(Context); 159 } 160 161 if (T.isNull()) 162 T = Context.getTypeDeclType(TD); 163 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 164 // Check whether we can use this interface. 165 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 166 167 T = Context.getObjCInterfaceType(IDecl); 168 } else 169 return 0; 170 171 if (SS) 172 T = getQualifiedNameType(*SS, T); 173 174 return T.getAsOpaquePtr(); 175 } 176 177 return 0; 178} 179 180/// isTagName() - This method is called *for error recovery purposes only* 181/// to determine if the specified name is a valid tag name ("struct foo"). If 182/// so, this returns the TST for the tag corresponding to it (TST_enum, 183/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 184/// where the user forgot to specify the tag. 185DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 186 // Do a tag name lookup in this scope. 187 LookupResult R; 188 LookupName(R, S, &II, LookupTagName, false, false); 189 if (R.getKind() == LookupResult::Found) 190 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 191 switch (TD->getTagKind()) { 192 case TagDecl::TK_struct: return DeclSpec::TST_struct; 193 case TagDecl::TK_union: return DeclSpec::TST_union; 194 case TagDecl::TK_class: return DeclSpec::TST_class; 195 case TagDecl::TK_enum: return DeclSpec::TST_enum; 196 } 197 } 198 199 return DeclSpec::TST_unspecified; 200} 201 202 203// Determines the context to return to after temporarily entering a 204// context. This depends in an unnecessarily complicated way on the 205// exact ordering of callbacks from the parser. 206DeclContext *Sema::getContainingDC(DeclContext *DC) { 207 208 // Functions defined inline within classes aren't parsed until we've 209 // finished parsing the top-level class, so the top-level class is 210 // the context we'll need to return to. 211 if (isa<FunctionDecl>(DC)) { 212 DC = DC->getLexicalParent(); 213 214 // A function not defined within a class will always return to its 215 // lexical context. 216 if (!isa<CXXRecordDecl>(DC)) 217 return DC; 218 219 // A C++ inline method/friend is parsed *after* the topmost class 220 // it was declared in is fully parsed ("complete"); the topmost 221 // class is the context we need to return to. 222 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 223 DC = RD; 224 225 // Return the declaration context of the topmost class the inline method is 226 // declared in. 227 return DC; 228 } 229 230 if (isa<ObjCMethodDecl>(DC)) 231 return Context.getTranslationUnitDecl(); 232 233 return DC->getLexicalParent(); 234} 235 236void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 237 assert(getContainingDC(DC) == CurContext && 238 "The next DeclContext should be lexically contained in the current one."); 239 CurContext = DC; 240 S->setEntity(DC); 241} 242 243void Sema::PopDeclContext() { 244 assert(CurContext && "DeclContext imbalance!"); 245 246 CurContext = getContainingDC(CurContext); 247} 248 249/// EnterDeclaratorContext - Used when we must lookup names in the context 250/// of a declarator's nested name specifier. 251void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 252 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 253 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 254 CurContext = DC; 255 assert(CurContext && "No context?"); 256 S->setEntity(CurContext); 257} 258 259void Sema::ExitDeclaratorContext(Scope *S) { 260 S->setEntity(PreDeclaratorDC); 261 PreDeclaratorDC = 0; 262 263 // Reset CurContext to the nearest enclosing context. 264 while (!S->getEntity() && S->getParent()) 265 S = S->getParent(); 266 CurContext = static_cast<DeclContext*>(S->getEntity()); 267 assert(CurContext && "No context?"); 268} 269 270/// \brief Determine whether we allow overloading of the function 271/// PrevDecl with another declaration. 272/// 273/// This routine determines whether overloading is possible, not 274/// whether some new function is actually an overload. It will return 275/// true in C++ (where we can always provide overloads) or, as an 276/// extension, in C when the previous function is already an 277/// overloaded function declaration or has the "overloadable" 278/// attribute. 279static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 280 if (Context.getLangOptions().CPlusPlus) 281 return true; 282 283 if (isa<OverloadedFunctionDecl>(PrevDecl)) 284 return true; 285 286 return PrevDecl->getAttr<OverloadableAttr>() != 0; 287} 288 289/// Add this decl to the scope shadowed decl chains. 290void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 291 // Move up the scope chain until we find the nearest enclosing 292 // non-transparent context. The declaration will be introduced into this 293 // scope. 294 while (S->getEntity() && 295 ((DeclContext *)S->getEntity())->isTransparentContext()) 296 S = S->getParent(); 297 298 // Add scoped declarations into their context, so that they can be 299 // found later. Declarations without a context won't be inserted 300 // into any context. 301 if (AddToContext) 302 CurContext->addDecl(D); 303 304 // Out-of-line function and variable definitions should not be pushed into 305 // scope. 306 if ((isa<FunctionTemplateDecl>(D) && 307 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 308 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 309 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 310 return; 311 312 // If this replaces anything in the current scope, 313 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 314 IEnd = IdResolver.end(); 315 for (; I != IEnd; ++I) { 316 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 317 S->RemoveDecl(DeclPtrTy::make(*I)); 318 IdResolver.RemoveDecl(*I); 319 320 // Should only need to replace one decl. 321 break; 322 } 323 } 324 325 S->AddDecl(DeclPtrTy::make(D)); 326 IdResolver.AddDecl(D); 327} 328 329bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 330 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 331 // Look inside the overload set to determine if any of the declarations 332 // are in scope. (Possibly) build a new overload set containing only 333 // those declarations that are in scope. 334 OverloadedFunctionDecl *NewOvl = 0; 335 bool FoundInScope = false; 336 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 337 FEnd = Ovl->function_end(); 338 F != FEnd; ++F) { 339 NamedDecl *FD = F->get(); 340 if (!isDeclInScope(FD, Ctx, S)) { 341 if (!NewOvl && F != Ovl->function_begin()) { 342 NewOvl = OverloadedFunctionDecl::Create(Context, 343 F->get()->getDeclContext(), 344 F->get()->getDeclName()); 345 D = NewOvl; 346 for (OverloadedFunctionDecl::function_iterator 347 First = Ovl->function_begin(); 348 First != F; ++First) 349 NewOvl->addOverload(*First); 350 } 351 } else { 352 FoundInScope = true; 353 if (NewOvl) 354 NewOvl->addOverload(*F); 355 } 356 } 357 358 return FoundInScope; 359 } 360 361 return IdResolver.isDeclInScope(D, Ctx, Context, S); 362} 363 364void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 365 if (S->decl_empty()) return; 366 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 367 "Scope shouldn't contain decls!"); 368 369 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 370 I != E; ++I) { 371 Decl *TmpD = (*I).getAs<Decl>(); 372 assert(TmpD && "This decl didn't get pushed??"); 373 374 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 375 NamedDecl *D = cast<NamedDecl>(TmpD); 376 377 if (!D->getDeclName()) continue; 378 379 // Diagnose unused variables in this scope. 380 if (!D->isUsed() && !D->hasAttr<UnusedAttr>() && isa<VarDecl>(D) && 381 !isa<ParmVarDecl>(D) && !isa<ImplicitParamDecl>(D) && 382 D->getDeclContext()->isFunctionOrMethod()) 383 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 384 385 // Remove this name from our lexical scope. 386 IdResolver.RemoveDecl(D); 387 } 388} 389 390/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 391/// return 0 if one not found. 392ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 393 // The third "scope" argument is 0 since we aren't enabling lazy built-in 394 // creation from this context. 395 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 396 397 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 398} 399 400/// getNonFieldDeclScope - Retrieves the innermost scope, starting 401/// from S, where a non-field would be declared. This routine copes 402/// with the difference between C and C++ scoping rules in structs and 403/// unions. For example, the following code is well-formed in C but 404/// ill-formed in C++: 405/// @code 406/// struct S6 { 407/// enum { BAR } e; 408/// }; 409/// 410/// void test_S6() { 411/// struct S6 a; 412/// a.e = BAR; 413/// } 414/// @endcode 415/// For the declaration of BAR, this routine will return a different 416/// scope. The scope S will be the scope of the unnamed enumeration 417/// within S6. In C++, this routine will return the scope associated 418/// with S6, because the enumeration's scope is a transparent 419/// context but structures can contain non-field names. In C, this 420/// routine will return the translation unit scope, since the 421/// enumeration's scope is a transparent context and structures cannot 422/// contain non-field names. 423Scope *Sema::getNonFieldDeclScope(Scope *S) { 424 while (((S->getFlags() & Scope::DeclScope) == 0) || 425 (S->getEntity() && 426 ((DeclContext *)S->getEntity())->isTransparentContext()) || 427 (S->isClassScope() && !getLangOptions().CPlusPlus)) 428 S = S->getParent(); 429 return S; 430} 431 432void Sema::InitBuiltinVaListType() { 433 if (!Context.getBuiltinVaListType().isNull()) 434 return; 435 436 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 437 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 438 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 439 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 440} 441 442/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 443/// file scope. lazily create a decl for it. ForRedeclaration is true 444/// if we're creating this built-in in anticipation of redeclaring the 445/// built-in. 446NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 447 Scope *S, bool ForRedeclaration, 448 SourceLocation Loc) { 449 Builtin::ID BID = (Builtin::ID)bid; 450 451 if (Context.BuiltinInfo.hasVAListUse(BID)) 452 InitBuiltinVaListType(); 453 454 ASTContext::GetBuiltinTypeError Error; 455 QualType R = Context.GetBuiltinType(BID, Error); 456 switch (Error) { 457 case ASTContext::GE_None: 458 // Okay 459 break; 460 461 case ASTContext::GE_Missing_stdio: 462 if (ForRedeclaration) 463 Diag(Loc, diag::err_implicit_decl_requires_stdio) 464 << Context.BuiltinInfo.GetName(BID); 465 return 0; 466 467 case ASTContext::GE_Missing_setjmp: 468 if (ForRedeclaration) 469 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 470 << Context.BuiltinInfo.GetName(BID); 471 return 0; 472 } 473 474 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 475 Diag(Loc, diag::ext_implicit_lib_function_decl) 476 << Context.BuiltinInfo.GetName(BID) 477 << R; 478 if (Context.BuiltinInfo.getHeaderName(BID) && 479 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 480 != Diagnostic::Ignored) 481 Diag(Loc, diag::note_please_include_header) 482 << Context.BuiltinInfo.getHeaderName(BID) 483 << Context.BuiltinInfo.GetName(BID); 484 } 485 486 FunctionDecl *New = FunctionDecl::Create(Context, 487 Context.getTranslationUnitDecl(), 488 Loc, II, R, /*DInfo=*/0, 489 FunctionDecl::Extern, false, 490 /*hasPrototype=*/true); 491 New->setImplicit(); 492 493 // Create Decl objects for each parameter, adding them to the 494 // FunctionDecl. 495 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 496 llvm::SmallVector<ParmVarDecl*, 16> Params; 497 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 498 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 499 FT->getArgType(i), /*DInfo=*/0, 500 VarDecl::None, 0)); 501 New->setParams(Context, Params.data(), Params.size()); 502 } 503 504 AddKnownFunctionAttributes(New); 505 506 // TUScope is the translation-unit scope to insert this function into. 507 // FIXME: This is hideous. We need to teach PushOnScopeChains to 508 // relate Scopes to DeclContexts, and probably eliminate CurContext 509 // entirely, but we're not there yet. 510 DeclContext *SavedContext = CurContext; 511 CurContext = Context.getTranslationUnitDecl(); 512 PushOnScopeChains(New, TUScope); 513 CurContext = SavedContext; 514 return New; 515} 516 517/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 518/// same name and scope as a previous declaration 'Old'. Figure out 519/// how to resolve this situation, merging decls or emitting 520/// diagnostics as appropriate. If there was an error, set New to be invalid. 521/// 522void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 523 // If either decl is known invalid already, set the new one to be invalid and 524 // don't bother doing any merging checks. 525 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 526 return New->setInvalidDecl(); 527 528 // Allow multiple definitions for ObjC built-in typedefs. 529 // FIXME: Verify the underlying types are equivalent! 530 if (getLangOptions().ObjC1) { 531 const IdentifierInfo *TypeID = New->getIdentifier(); 532 switch (TypeID->getLength()) { 533 default: break; 534 case 2: 535 if (!TypeID->isStr("id")) 536 break; 537 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 538 // Install the built-in type for 'id', ignoring the current definition. 539 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 540 return; 541 case 5: 542 if (!TypeID->isStr("Class")) 543 break; 544 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 545 // Install the built-in type for 'Class', ignoring the current definition. 546 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 547 return; 548 case 3: 549 if (!TypeID->isStr("SEL")) 550 break; 551 Context.setObjCSelType(Context.getTypeDeclType(New)); 552 return; 553 case 8: 554 if (!TypeID->isStr("Protocol")) 555 break; 556 Context.setObjCProtoType(New->getUnderlyingType()); 557 return; 558 } 559 // Fall through - the typedef name was not a builtin type. 560 } 561 // Verify the old decl was also a type. 562 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 563 if (!Old) { 564 Diag(New->getLocation(), diag::err_redefinition_different_kind) 565 << New->getDeclName(); 566 if (OldD->getLocation().isValid()) 567 Diag(OldD->getLocation(), diag::note_previous_definition); 568 return New->setInvalidDecl(); 569 } 570 571 // Determine the "old" type we'll use for checking and diagnostics. 572 QualType OldType; 573 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 574 OldType = OldTypedef->getUnderlyingType(); 575 else 576 OldType = Context.getTypeDeclType(Old); 577 578 // If the typedef types are not identical, reject them in all languages and 579 // with any extensions enabled. 580 581 if (OldType != New->getUnderlyingType() && 582 Context.getCanonicalType(OldType) != 583 Context.getCanonicalType(New->getUnderlyingType())) { 584 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 585 << New->getUnderlyingType() << OldType; 586 if (Old->getLocation().isValid()) 587 Diag(Old->getLocation(), diag::note_previous_definition); 588 return New->setInvalidDecl(); 589 } 590 591 if (getLangOptions().Microsoft) 592 return; 593 594 // C++ [dcl.typedef]p2: 595 // In a given non-class scope, a typedef specifier can be used to 596 // redefine the name of any type declared in that scope to refer 597 // to the type to which it already refers. 598 if (getLangOptions().CPlusPlus) { 599 if (!isa<CXXRecordDecl>(CurContext)) 600 return; 601 Diag(New->getLocation(), diag::err_redefinition) 602 << New->getDeclName(); 603 Diag(Old->getLocation(), diag::note_previous_definition); 604 return New->setInvalidDecl(); 605 } 606 607 // If we have a redefinition of a typedef in C, emit a warning. This warning 608 // is normally mapped to an error, but can be controlled with 609 // -Wtypedef-redefinition. If either the original or the redefinition is 610 // in a system header, don't emit this for compatibility with GCC. 611 if (PP.getDiagnostics().getSuppressSystemWarnings() && 612 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 613 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 614 return; 615 616 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 617 << New->getDeclName(); 618 Diag(Old->getLocation(), diag::note_previous_definition); 619 return; 620} 621 622/// DeclhasAttr - returns true if decl Declaration already has the target 623/// attribute. 624static bool 625DeclHasAttr(const Decl *decl, const Attr *target) { 626 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 627 if (attr->getKind() == target->getKind()) 628 return true; 629 630 return false; 631} 632 633/// MergeAttributes - append attributes from the Old decl to the New one. 634static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 635 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 636 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 637 Attr *NewAttr = attr->clone(C); 638 NewAttr->setInherited(true); 639 New->addAttr(NewAttr); 640 } 641 } 642} 643 644/// Used in MergeFunctionDecl to keep track of function parameters in 645/// C. 646struct GNUCompatibleParamWarning { 647 ParmVarDecl *OldParm; 648 ParmVarDecl *NewParm; 649 QualType PromotedType; 650}; 651 652/// MergeFunctionDecl - We just parsed a function 'New' from 653/// declarator D which has the same name and scope as a previous 654/// declaration 'Old'. Figure out how to resolve this situation, 655/// merging decls or emitting diagnostics as appropriate. 656/// 657/// In C++, New and Old must be declarations that are not 658/// overloaded. Use IsOverload to determine whether New and Old are 659/// overloaded, and to select the Old declaration that New should be 660/// merged with. 661/// 662/// Returns true if there was an error, false otherwise. 663bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 664 assert(!isa<OverloadedFunctionDecl>(OldD) && 665 "Cannot merge with an overloaded function declaration"); 666 667 // Verify the old decl was also a function. 668 FunctionDecl *Old = 0; 669 if (FunctionTemplateDecl *OldFunctionTemplate 670 = dyn_cast<FunctionTemplateDecl>(OldD)) 671 Old = OldFunctionTemplate->getTemplatedDecl(); 672 else 673 Old = dyn_cast<FunctionDecl>(OldD); 674 if (!Old) { 675 Diag(New->getLocation(), diag::err_redefinition_different_kind) 676 << New->getDeclName(); 677 Diag(OldD->getLocation(), diag::note_previous_definition); 678 return true; 679 } 680 681 // Determine whether the previous declaration was a definition, 682 // implicit declaration, or a declaration. 683 diag::kind PrevDiag; 684 if (Old->isThisDeclarationADefinition()) 685 PrevDiag = diag::note_previous_definition; 686 else if (Old->isImplicit()) 687 PrevDiag = diag::note_previous_implicit_declaration; 688 else 689 PrevDiag = diag::note_previous_declaration; 690 691 QualType OldQType = Context.getCanonicalType(Old->getType()); 692 QualType NewQType = Context.getCanonicalType(New->getType()); 693 694 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 695 New->getStorageClass() == FunctionDecl::Static && 696 Old->getStorageClass() != FunctionDecl::Static) { 697 Diag(New->getLocation(), diag::err_static_non_static) 698 << New; 699 Diag(Old->getLocation(), PrevDiag); 700 return true; 701 } 702 703 if (getLangOptions().CPlusPlus) { 704 // (C++98 13.1p2): 705 // Certain function declarations cannot be overloaded: 706 // -- Function declarations that differ only in the return type 707 // cannot be overloaded. 708 QualType OldReturnType 709 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 710 QualType NewReturnType 711 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 712 if (OldReturnType != NewReturnType) { 713 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 714 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 715 return true; 716 } 717 718 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 719 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 720 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 721 NewMethod->getLexicalDeclContext()->isRecord()) { 722 // -- Member function declarations with the same name and the 723 // same parameter types cannot be overloaded if any of them 724 // is a static member function declaration. 725 if (OldMethod->isStatic() || NewMethod->isStatic()) { 726 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 727 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 728 return true; 729 } 730 731 // C++ [class.mem]p1: 732 // [...] A member shall not be declared twice in the 733 // member-specification, except that a nested class or member 734 // class template can be declared and then later defined. 735 unsigned NewDiag; 736 if (isa<CXXConstructorDecl>(OldMethod)) 737 NewDiag = diag::err_constructor_redeclared; 738 else if (isa<CXXDestructorDecl>(NewMethod)) 739 NewDiag = diag::err_destructor_redeclared; 740 else if (isa<CXXConversionDecl>(NewMethod)) 741 NewDiag = diag::err_conv_function_redeclared; 742 else 743 NewDiag = diag::err_member_redeclared; 744 745 Diag(New->getLocation(), NewDiag); 746 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 747 } 748 749 // (C++98 8.3.5p3): 750 // All declarations for a function shall agree exactly in both the 751 // return type and the parameter-type-list. 752 if (OldQType == NewQType) 753 return MergeCompatibleFunctionDecls(New, Old); 754 755 // Fall through for conflicting redeclarations and redefinitions. 756 } 757 758 // C: Function types need to be compatible, not identical. This handles 759 // duplicate function decls like "void f(int); void f(enum X);" properly. 760 if (!getLangOptions().CPlusPlus && 761 Context.typesAreCompatible(OldQType, NewQType)) { 762 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 763 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 764 const FunctionProtoType *OldProto = 0; 765 if (isa<FunctionNoProtoType>(NewFuncType) && 766 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 767 // The old declaration provided a function prototype, but the 768 // new declaration does not. Merge in the prototype. 769 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 770 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 771 OldProto->arg_type_end()); 772 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 773 ParamTypes.data(), ParamTypes.size(), 774 OldProto->isVariadic(), 775 OldProto->getTypeQuals()); 776 New->setType(NewQType); 777 New->setHasInheritedPrototype(); 778 779 // Synthesize a parameter for each argument type. 780 llvm::SmallVector<ParmVarDecl*, 16> Params; 781 for (FunctionProtoType::arg_type_iterator 782 ParamType = OldProto->arg_type_begin(), 783 ParamEnd = OldProto->arg_type_end(); 784 ParamType != ParamEnd; ++ParamType) { 785 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 786 SourceLocation(), 0, 787 *ParamType, /*DInfo=*/0, 788 VarDecl::None, 0); 789 Param->setImplicit(); 790 Params.push_back(Param); 791 } 792 793 New->setParams(Context, Params.data(), Params.size()); 794 } 795 796 return MergeCompatibleFunctionDecls(New, Old); 797 } 798 799 // GNU C permits a K&R definition to follow a prototype declaration 800 // if the declared types of the parameters in the K&R definition 801 // match the types in the prototype declaration, even when the 802 // promoted types of the parameters from the K&R definition differ 803 // from the types in the prototype. GCC then keeps the types from 804 // the prototype. 805 // 806 // If a variadic prototype is followed by a non-variadic K&R definition, 807 // the K&R definition becomes variadic. This is sort of an edge case, but 808 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 809 // C99 6.9.1p8. 810 if (!getLangOptions().CPlusPlus && 811 Old->hasPrototype() && !New->hasPrototype() && 812 New->getType()->getAs<FunctionProtoType>() && 813 Old->getNumParams() == New->getNumParams()) { 814 llvm::SmallVector<QualType, 16> ArgTypes; 815 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 816 const FunctionProtoType *OldProto 817 = Old->getType()->getAs<FunctionProtoType>(); 818 const FunctionProtoType *NewProto 819 = New->getType()->getAs<FunctionProtoType>(); 820 821 // Determine whether this is the GNU C extension. 822 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 823 NewProto->getResultType()); 824 bool LooseCompatible = !MergedReturn.isNull(); 825 for (unsigned Idx = 0, End = Old->getNumParams(); 826 LooseCompatible && Idx != End; ++Idx) { 827 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 828 ParmVarDecl *NewParm = New->getParamDecl(Idx); 829 if (Context.typesAreCompatible(OldParm->getType(), 830 NewProto->getArgType(Idx))) { 831 ArgTypes.push_back(NewParm->getType()); 832 } else if (Context.typesAreCompatible(OldParm->getType(), 833 NewParm->getType())) { 834 GNUCompatibleParamWarning Warn 835 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 836 Warnings.push_back(Warn); 837 ArgTypes.push_back(NewParm->getType()); 838 } else 839 LooseCompatible = false; 840 } 841 842 if (LooseCompatible) { 843 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 844 Diag(Warnings[Warn].NewParm->getLocation(), 845 diag::ext_param_promoted_not_compatible_with_prototype) 846 << Warnings[Warn].PromotedType 847 << Warnings[Warn].OldParm->getType(); 848 Diag(Warnings[Warn].OldParm->getLocation(), 849 diag::note_previous_declaration); 850 } 851 852 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 853 ArgTypes.size(), 854 OldProto->isVariadic(), 0)); 855 return MergeCompatibleFunctionDecls(New, Old); 856 } 857 858 // Fall through to diagnose conflicting types. 859 } 860 861 // A function that has already been declared has been redeclared or defined 862 // with a different type- show appropriate diagnostic 863 if (unsigned BuiltinID = Old->getBuiltinID()) { 864 // The user has declared a builtin function with an incompatible 865 // signature. 866 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 867 // The function the user is redeclaring is a library-defined 868 // function like 'malloc' or 'printf'. Warn about the 869 // redeclaration, then pretend that we don't know about this 870 // library built-in. 871 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 872 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 873 << Old << Old->getType(); 874 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 875 Old->setInvalidDecl(); 876 return false; 877 } 878 879 PrevDiag = diag::note_previous_builtin_declaration; 880 } 881 882 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 883 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 884 return true; 885} 886 887/// \brief Completes the merge of two function declarations that are 888/// known to be compatible. 889/// 890/// This routine handles the merging of attributes and other 891/// properties of function declarations form the old declaration to 892/// the new declaration, once we know that New is in fact a 893/// redeclaration of Old. 894/// 895/// \returns false 896bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 897 // Merge the attributes 898 MergeAttributes(New, Old, Context); 899 900 // Merge the storage class. 901 if (Old->getStorageClass() != FunctionDecl::Extern && 902 Old->getStorageClass() != FunctionDecl::None) 903 New->setStorageClass(Old->getStorageClass()); 904 905 // Merge "pure" flag. 906 if (Old->isPure()) 907 New->setPure(); 908 909 // Merge the "deleted" flag. 910 if (Old->isDeleted()) 911 New->setDeleted(); 912 913 if (getLangOptions().CPlusPlus) 914 return MergeCXXFunctionDecl(New, Old); 915 916 return false; 917} 918 919/// MergeVarDecl - We just parsed a variable 'New' which has the same name 920/// and scope as a previous declaration 'Old'. Figure out how to resolve this 921/// situation, merging decls or emitting diagnostics as appropriate. 922/// 923/// Tentative definition rules (C99 6.9.2p2) are checked by 924/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 925/// definitions here, since the initializer hasn't been attached. 926/// 927void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 928 // If either decl is invalid, make sure the new one is marked invalid and 929 // don't do any other checking. 930 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 931 return New->setInvalidDecl(); 932 933 // Verify the old decl was also a variable. 934 VarDecl *Old = dyn_cast<VarDecl>(OldD); 935 if (!Old) { 936 Diag(New->getLocation(), diag::err_redefinition_different_kind) 937 << New->getDeclName(); 938 Diag(OldD->getLocation(), diag::note_previous_definition); 939 return New->setInvalidDecl(); 940 } 941 942 MergeAttributes(New, Old, Context); 943 944 // Merge the types 945 QualType MergedT; 946 if (getLangOptions().CPlusPlus) { 947 if (Context.hasSameType(New->getType(), Old->getType())) 948 MergedT = New->getType(); 949 // C++ [basic.types]p7: 950 // [...] The declared type of an array object might be an array of 951 // unknown size and therefore be incomplete at one point in a 952 // translation unit and complete later on; [...] 953 else if (Old->getType()->isIncompleteArrayType() && 954 New->getType()->isArrayType()) { 955 CanQual<ArrayType> OldArray 956 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 957 CanQual<ArrayType> NewArray 958 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 959 if (OldArray->getElementType() == NewArray->getElementType()) 960 MergedT = New->getType(); 961 } 962 } else { 963 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 964 } 965 if (MergedT.isNull()) { 966 Diag(New->getLocation(), diag::err_redefinition_different_type) 967 << New->getDeclName(); 968 Diag(Old->getLocation(), diag::note_previous_definition); 969 return New->setInvalidDecl(); 970 } 971 New->setType(MergedT); 972 973 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 974 if (New->getStorageClass() == VarDecl::Static && 975 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 976 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 977 Diag(Old->getLocation(), diag::note_previous_definition); 978 return New->setInvalidDecl(); 979 } 980 // C99 6.2.2p4: 981 // For an identifier declared with the storage-class specifier 982 // extern in a scope in which a prior declaration of that 983 // identifier is visible,23) if the prior declaration specifies 984 // internal or external linkage, the linkage of the identifier at 985 // the later declaration is the same as the linkage specified at 986 // the prior declaration. If no prior declaration is visible, or 987 // if the prior declaration specifies no linkage, then the 988 // identifier has external linkage. 989 if (New->hasExternalStorage() && Old->hasLinkage()) 990 /* Okay */; 991 else if (New->getStorageClass() != VarDecl::Static && 992 Old->getStorageClass() == VarDecl::Static) { 993 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 994 Diag(Old->getLocation(), diag::note_previous_definition); 995 return New->setInvalidDecl(); 996 } 997 998 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 999 1000 // FIXME: The test for external storage here seems wrong? We still 1001 // need to check for mismatches. 1002 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1003 // Don't complain about out-of-line definitions of static members. 1004 !(Old->getLexicalDeclContext()->isRecord() && 1005 !New->getLexicalDeclContext()->isRecord())) { 1006 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1007 Diag(Old->getLocation(), diag::note_previous_definition); 1008 return New->setInvalidDecl(); 1009 } 1010 1011 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1012 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1013 Diag(Old->getLocation(), diag::note_previous_definition); 1014 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1015 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1016 Diag(Old->getLocation(), diag::note_previous_definition); 1017 } 1018 1019 // Keep a chain of previous declarations. 1020 New->setPreviousDeclaration(Old); 1021} 1022 1023/// CheckFallThrough - Check that we don't fall off the end of a 1024/// Statement that should return a value. 1025/// 1026/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1027/// MaybeFallThrough iff we might or might not fall off the end and 1028/// NeverFallThrough iff we never fall off the end of the statement. We assume 1029/// that functions not marked noreturn will return. 1030Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1031 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1032 1033 // FIXME: They should never return 0, fix that, delete this code. 1034 if (cfg == 0) 1035 return NeverFallThrough; 1036 // The CFG leaves in dead things, and we don't want to dead code paths to 1037 // confuse us, so we mark all live things first. 1038 std::queue<CFGBlock*> workq; 1039 llvm::BitVector live(cfg->getNumBlockIDs()); 1040 // Prep work queue 1041 workq.push(&cfg->getEntry()); 1042 // Solve 1043 while (!workq.empty()) { 1044 CFGBlock *item = workq.front(); 1045 workq.pop(); 1046 live.set(item->getBlockID()); 1047 for (CFGBlock::succ_iterator I=item->succ_begin(), 1048 E=item->succ_end(); 1049 I != E; 1050 ++I) { 1051 if ((*I) && !live[(*I)->getBlockID()]) { 1052 live.set((*I)->getBlockID()); 1053 workq.push(*I); 1054 } 1055 } 1056 } 1057 1058 // Now we know what is live, we check the live precessors of the exit block 1059 // and look for fall through paths, being careful to ignore normal returns, 1060 // and exceptional paths. 1061 bool HasLiveReturn = false; 1062 bool HasFakeEdge = false; 1063 bool HasPlainEdge = false; 1064 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1065 E = cfg->getExit().pred_end(); 1066 I != E; 1067 ++I) { 1068 CFGBlock& B = **I; 1069 if (!live[B.getBlockID()]) 1070 continue; 1071 if (B.size() == 0) { 1072 // A labeled empty statement, or the entry block... 1073 HasPlainEdge = true; 1074 continue; 1075 } 1076 Stmt *S = B[B.size()-1]; 1077 if (isa<ReturnStmt>(S)) { 1078 HasLiveReturn = true; 1079 continue; 1080 } 1081 if (isa<ObjCAtThrowStmt>(S)) { 1082 HasFakeEdge = true; 1083 continue; 1084 } 1085 if (isa<CXXThrowExpr>(S)) { 1086 HasFakeEdge = true; 1087 continue; 1088 } 1089 bool NoReturnEdge = false; 1090 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1091 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1092 if (CEE->getType().getNoReturnAttr()) { 1093 NoReturnEdge = true; 1094 HasFakeEdge = true; 1095 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1096 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1097 if (FD->hasAttr<NoReturnAttr>()) { 1098 NoReturnEdge = true; 1099 HasFakeEdge = true; 1100 } 1101 } 1102 } 1103 } 1104 // FIXME: Add noreturn message sends. 1105 if (NoReturnEdge == false) 1106 HasPlainEdge = true; 1107 } 1108 if (!HasPlainEdge) 1109 return NeverFallThrough; 1110 if (HasFakeEdge || HasLiveReturn) 1111 return MaybeFallThrough; 1112 // This says AlwaysFallThrough for calls to functions that are not marked 1113 // noreturn, that don't return. If people would like this warning to be more 1114 // accurate, such functions should be marked as noreturn. 1115 return AlwaysFallThrough; 1116} 1117 1118/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1119/// function that should return a value. Check that we don't fall off the end 1120/// of a noreturn function. We assume that functions and blocks not marked 1121/// noreturn will return. 1122void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1123 // FIXME: Would be nice if we had a better way to control cascading errors, 1124 // but for now, avoid them. The problem is that when Parse sees: 1125 // int foo() { return a; } 1126 // The return is eaten and the Sema code sees just: 1127 // int foo() { } 1128 // which this code would then warn about. 1129 if (getDiagnostics().hasErrorOccurred()) 1130 return; 1131 bool ReturnsVoid = false; 1132 bool HasNoReturn = false; 1133 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1134 // If the result type of the function is a dependent type, we don't know 1135 // whether it will be void or not, so don't 1136 if (FD->getResultType()->isDependentType()) 1137 return; 1138 if (FD->getResultType()->isVoidType()) 1139 ReturnsVoid = true; 1140 if (FD->hasAttr<NoReturnAttr>()) 1141 HasNoReturn = true; 1142 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1143 if (MD->getResultType()->isVoidType()) 1144 ReturnsVoid = true; 1145 if (MD->hasAttr<NoReturnAttr>()) 1146 HasNoReturn = true; 1147 } 1148 1149 // Short circuit for compilation speed. 1150 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1151 == Diagnostic::Ignored || ReturnsVoid) 1152 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1153 == Diagnostic::Ignored || !HasNoReturn) 1154 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1155 == Diagnostic::Ignored || !ReturnsVoid)) 1156 return; 1157 // FIXME: Function try block 1158 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1159 switch (CheckFallThrough(Body)) { 1160 case MaybeFallThrough: 1161 if (HasNoReturn) 1162 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1163 else if (!ReturnsVoid) 1164 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1165 break; 1166 case AlwaysFallThrough: 1167 if (HasNoReturn) 1168 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1169 else if (!ReturnsVoid) 1170 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1171 break; 1172 case NeverFallThrough: 1173 if (ReturnsVoid) 1174 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1175 break; 1176 } 1177 } 1178} 1179 1180/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1181/// that should return a value. Check that we don't fall off the end of a 1182/// noreturn block. We assume that functions and blocks not marked noreturn 1183/// will return. 1184void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1185 // FIXME: Would be nice if we had a better way to control cascading errors, 1186 // but for now, avoid them. The problem is that when Parse sees: 1187 // int foo() { return a; } 1188 // The return is eaten and the Sema code sees just: 1189 // int foo() { } 1190 // which this code would then warn about. 1191 if (getDiagnostics().hasErrorOccurred()) 1192 return; 1193 bool ReturnsVoid = false; 1194 bool HasNoReturn = false; 1195 if (const FunctionType *FT = BlockTy->getPointeeType()->getAs<FunctionType>()) { 1196 if (FT->getResultType()->isVoidType()) 1197 ReturnsVoid = true; 1198 if (FT->getNoReturnAttr()) 1199 HasNoReturn = true; 1200 } 1201 1202 // Short circuit for compilation speed. 1203 if (ReturnsVoid 1204 && !HasNoReturn 1205 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1206 == Diagnostic::Ignored || !ReturnsVoid)) 1207 return; 1208 // FIXME: Funtion try block 1209 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1210 switch (CheckFallThrough(Body)) { 1211 case MaybeFallThrough: 1212 if (HasNoReturn) 1213 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1214 else if (!ReturnsVoid) 1215 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1216 break; 1217 case AlwaysFallThrough: 1218 if (HasNoReturn) 1219 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1220 else if (!ReturnsVoid) 1221 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1222 break; 1223 case NeverFallThrough: 1224 if (ReturnsVoid) 1225 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1226 break; 1227 } 1228 } 1229} 1230 1231/// CheckParmsForFunctionDef - Check that the parameters of the given 1232/// function are appropriate for the definition of a function. This 1233/// takes care of any checks that cannot be performed on the 1234/// declaration itself, e.g., that the types of each of the function 1235/// parameters are complete. 1236bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1237 bool HasInvalidParm = false; 1238 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1239 ParmVarDecl *Param = FD->getParamDecl(p); 1240 1241 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1242 // function declarator that is part of a function definition of 1243 // that function shall not have incomplete type. 1244 // 1245 // This is also C++ [dcl.fct]p6. 1246 if (!Param->isInvalidDecl() && 1247 RequireCompleteType(Param->getLocation(), Param->getType(), 1248 diag::err_typecheck_decl_incomplete_type)) { 1249 Param->setInvalidDecl(); 1250 HasInvalidParm = true; 1251 } 1252 1253 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1254 // declaration of each parameter shall include an identifier. 1255 if (Param->getIdentifier() == 0 && 1256 !Param->isImplicit() && 1257 !getLangOptions().CPlusPlus) 1258 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1259 } 1260 1261 return HasInvalidParm; 1262} 1263 1264/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1265/// no declarator (e.g. "struct foo;") is parsed. 1266Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1267 // FIXME: Error on auto/register at file scope 1268 // FIXME: Error on inline/virtual/explicit 1269 // FIXME: Error on invalid restrict 1270 // FIXME: Warn on useless __thread 1271 // FIXME: Warn on useless const/volatile 1272 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1273 // FIXME: Warn on useless attributes 1274 Decl *TagD = 0; 1275 TagDecl *Tag = 0; 1276 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1277 DS.getTypeSpecType() == DeclSpec::TST_struct || 1278 DS.getTypeSpecType() == DeclSpec::TST_union || 1279 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1280 TagD = static_cast<Decl *>(DS.getTypeRep()); 1281 1282 if (!TagD) // We probably had an error 1283 return DeclPtrTy(); 1284 1285 // Note that the above type specs guarantee that the 1286 // type rep is a Decl, whereas in many of the others 1287 // it's a Type. 1288 Tag = dyn_cast<TagDecl>(TagD); 1289 } 1290 1291 if (DS.isFriendSpecified()) { 1292 // If we're dealing with a class template decl, assume that the 1293 // template routines are handling it. 1294 if (TagD && isa<ClassTemplateDecl>(TagD)) 1295 return DeclPtrTy(); 1296 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1297 } 1298 1299 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1300 if (!Record->getDeclName() && Record->isDefinition() && 1301 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1302 if (getLangOptions().CPlusPlus || 1303 Record->getDeclContext()->isRecord()) 1304 return BuildAnonymousStructOrUnion(S, DS, Record); 1305 1306 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1307 << DS.getSourceRange(); 1308 } 1309 1310 // Microsoft allows unnamed struct/union fields. Don't complain 1311 // about them. 1312 // FIXME: Should we support Microsoft's extensions in this area? 1313 if (Record->getDeclName() && getLangOptions().Microsoft) 1314 return DeclPtrTy::make(Tag); 1315 } 1316 1317 if (!DS.isMissingDeclaratorOk() && 1318 DS.getTypeSpecType() != DeclSpec::TST_error) { 1319 // Warn about typedefs of enums without names, since this is an 1320 // extension in both Microsoft an GNU. 1321 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1322 Tag && isa<EnumDecl>(Tag)) { 1323 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1324 << DS.getSourceRange(); 1325 return DeclPtrTy::make(Tag); 1326 } 1327 1328 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1329 << DS.getSourceRange(); 1330 return DeclPtrTy(); 1331 } 1332 1333 return DeclPtrTy::make(Tag); 1334} 1335 1336/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1337/// anonymous struct or union AnonRecord into the owning context Owner 1338/// and scope S. This routine will be invoked just after we realize 1339/// that an unnamed union or struct is actually an anonymous union or 1340/// struct, e.g., 1341/// 1342/// @code 1343/// union { 1344/// int i; 1345/// float f; 1346/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1347/// // f into the surrounding scope.x 1348/// @endcode 1349/// 1350/// This routine is recursive, injecting the names of nested anonymous 1351/// structs/unions into the owning context and scope as well. 1352bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1353 RecordDecl *AnonRecord) { 1354 bool Invalid = false; 1355 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1356 FEnd = AnonRecord->field_end(); 1357 F != FEnd; ++F) { 1358 if ((*F)->getDeclName()) { 1359 LookupResult R; 1360 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1361 LookupOrdinaryName, true); 1362 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1363 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1364 // C++ [class.union]p2: 1365 // The names of the members of an anonymous union shall be 1366 // distinct from the names of any other entity in the 1367 // scope in which the anonymous union is declared. 1368 unsigned diagKind 1369 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1370 : diag::err_anonymous_struct_member_redecl; 1371 Diag((*F)->getLocation(), diagKind) 1372 << (*F)->getDeclName(); 1373 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1374 Invalid = true; 1375 } else { 1376 // C++ [class.union]p2: 1377 // For the purpose of name lookup, after the anonymous union 1378 // definition, the members of the anonymous union are 1379 // considered to have been defined in the scope in which the 1380 // anonymous union is declared. 1381 Owner->makeDeclVisibleInContext(*F); 1382 S->AddDecl(DeclPtrTy::make(*F)); 1383 IdResolver.AddDecl(*F); 1384 } 1385 } else if (const RecordType *InnerRecordType 1386 = (*F)->getType()->getAs<RecordType>()) { 1387 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1388 if (InnerRecord->isAnonymousStructOrUnion()) 1389 Invalid = Invalid || 1390 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1391 } 1392 } 1393 1394 return Invalid; 1395} 1396 1397/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1398/// anonymous structure or union. Anonymous unions are a C++ feature 1399/// (C++ [class.union]) and a GNU C extension; anonymous structures 1400/// are a GNU C and GNU C++ extension. 1401Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1402 RecordDecl *Record) { 1403 DeclContext *Owner = Record->getDeclContext(); 1404 1405 // Diagnose whether this anonymous struct/union is an extension. 1406 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1407 Diag(Record->getLocation(), diag::ext_anonymous_union); 1408 else if (!Record->isUnion()) 1409 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1410 1411 // C and C++ require different kinds of checks for anonymous 1412 // structs/unions. 1413 bool Invalid = false; 1414 if (getLangOptions().CPlusPlus) { 1415 const char* PrevSpec = 0; 1416 unsigned DiagID; 1417 // C++ [class.union]p3: 1418 // Anonymous unions declared in a named namespace or in the 1419 // global namespace shall be declared static. 1420 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1421 (isa<TranslationUnitDecl>(Owner) || 1422 (isa<NamespaceDecl>(Owner) && 1423 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1424 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1425 Invalid = true; 1426 1427 // Recover by adding 'static'. 1428 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1429 PrevSpec, DiagID); 1430 } 1431 // C++ [class.union]p3: 1432 // A storage class is not allowed in a declaration of an 1433 // anonymous union in a class scope. 1434 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1435 isa<RecordDecl>(Owner)) { 1436 Diag(DS.getStorageClassSpecLoc(), 1437 diag::err_anonymous_union_with_storage_spec); 1438 Invalid = true; 1439 1440 // Recover by removing the storage specifier. 1441 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1442 PrevSpec, DiagID); 1443 } 1444 1445 // C++ [class.union]p2: 1446 // The member-specification of an anonymous union shall only 1447 // define non-static data members. [Note: nested types and 1448 // functions cannot be declared within an anonymous union. ] 1449 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1450 MemEnd = Record->decls_end(); 1451 Mem != MemEnd; ++Mem) { 1452 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1453 // C++ [class.union]p3: 1454 // An anonymous union shall not have private or protected 1455 // members (clause 11). 1456 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1457 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1458 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1459 Invalid = true; 1460 } 1461 } else if ((*Mem)->isImplicit()) { 1462 // Any implicit members are fine. 1463 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1464 // This is a type that showed up in an 1465 // elaborated-type-specifier inside the anonymous struct or 1466 // union, but which actually declares a type outside of the 1467 // anonymous struct or union. It's okay. 1468 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1469 if (!MemRecord->isAnonymousStructOrUnion() && 1470 MemRecord->getDeclName()) { 1471 // This is a nested type declaration. 1472 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1473 << (int)Record->isUnion(); 1474 Invalid = true; 1475 } 1476 } else { 1477 // We have something that isn't a non-static data 1478 // member. Complain about it. 1479 unsigned DK = diag::err_anonymous_record_bad_member; 1480 if (isa<TypeDecl>(*Mem)) 1481 DK = diag::err_anonymous_record_with_type; 1482 else if (isa<FunctionDecl>(*Mem)) 1483 DK = diag::err_anonymous_record_with_function; 1484 else if (isa<VarDecl>(*Mem)) 1485 DK = diag::err_anonymous_record_with_static; 1486 Diag((*Mem)->getLocation(), DK) 1487 << (int)Record->isUnion(); 1488 Invalid = true; 1489 } 1490 } 1491 } 1492 1493 if (!Record->isUnion() && !Owner->isRecord()) { 1494 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1495 << (int)getLangOptions().CPlusPlus; 1496 Invalid = true; 1497 } 1498 1499 // Create a declaration for this anonymous struct/union. 1500 NamedDecl *Anon = 0; 1501 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1502 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1503 /*IdentifierInfo=*/0, 1504 Context.getTypeDeclType(Record), 1505 // FIXME: Type source info. 1506 /*DInfo=*/0, 1507 /*BitWidth=*/0, /*Mutable=*/false); 1508 Anon->setAccess(AS_public); 1509 if (getLangOptions().CPlusPlus) 1510 FieldCollector->Add(cast<FieldDecl>(Anon)); 1511 } else { 1512 VarDecl::StorageClass SC; 1513 switch (DS.getStorageClassSpec()) { 1514 default: assert(0 && "Unknown storage class!"); 1515 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1516 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1517 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1518 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1519 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1520 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1521 case DeclSpec::SCS_mutable: 1522 // mutable can only appear on non-static class members, so it's always 1523 // an error here 1524 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1525 Invalid = true; 1526 SC = VarDecl::None; 1527 break; 1528 } 1529 1530 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1531 /*IdentifierInfo=*/0, 1532 Context.getTypeDeclType(Record), 1533 // FIXME: Type source info. 1534 /*DInfo=*/0, 1535 SC); 1536 } 1537 Anon->setImplicit(); 1538 1539 // Add the anonymous struct/union object to the current 1540 // context. We'll be referencing this object when we refer to one of 1541 // its members. 1542 Owner->addDecl(Anon); 1543 1544 // Inject the members of the anonymous struct/union into the owning 1545 // context and into the identifier resolver chain for name lookup 1546 // purposes. 1547 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1548 Invalid = true; 1549 1550 // Mark this as an anonymous struct/union type. Note that we do not 1551 // do this until after we have already checked and injected the 1552 // members of this anonymous struct/union type, because otherwise 1553 // the members could be injected twice: once by DeclContext when it 1554 // builds its lookup table, and once by 1555 // InjectAnonymousStructOrUnionMembers. 1556 Record->setAnonymousStructOrUnion(true); 1557 1558 if (Invalid) 1559 Anon->setInvalidDecl(); 1560 1561 return DeclPtrTy::make(Anon); 1562} 1563 1564 1565/// GetNameForDeclarator - Determine the full declaration name for the 1566/// given Declarator. 1567DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1568 switch (D.getKind()) { 1569 case Declarator::DK_Abstract: 1570 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1571 return DeclarationName(); 1572 1573 case Declarator::DK_Normal: 1574 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1575 return DeclarationName(D.getIdentifier()); 1576 1577 case Declarator::DK_Constructor: { 1578 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1579 return Context.DeclarationNames.getCXXConstructorName( 1580 Context.getCanonicalType(Ty)); 1581 } 1582 1583 case Declarator::DK_Destructor: { 1584 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1585 return Context.DeclarationNames.getCXXDestructorName( 1586 Context.getCanonicalType(Ty)); 1587 } 1588 1589 case Declarator::DK_Conversion: { 1590 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1591 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1592 return Context.DeclarationNames.getCXXConversionFunctionName( 1593 Context.getCanonicalType(Ty)); 1594 } 1595 1596 case Declarator::DK_Operator: 1597 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1598 return Context.DeclarationNames.getCXXOperatorName( 1599 D.getOverloadedOperator()); 1600 1601 case Declarator::DK_TemplateId: { 1602 TemplateName Name 1603 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1604 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1605 return Template->getDeclName(); 1606 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1607 return Ovl->getDeclName(); 1608 1609 return DeclarationName(); 1610 } 1611 } 1612 1613 assert(false && "Unknown name kind"); 1614 return DeclarationName(); 1615} 1616 1617/// isNearlyMatchingFunction - Determine whether the C++ functions 1618/// Declaration and Definition are "nearly" matching. This heuristic 1619/// is used to improve diagnostics in the case where an out-of-line 1620/// function definition doesn't match any declaration within 1621/// the class or namespace. 1622static bool isNearlyMatchingFunction(ASTContext &Context, 1623 FunctionDecl *Declaration, 1624 FunctionDecl *Definition) { 1625 if (Declaration->param_size() != Definition->param_size()) 1626 return false; 1627 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1628 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1629 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1630 1631 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1632 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1633 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1634 return false; 1635 } 1636 1637 return true; 1638} 1639 1640Sema::DeclPtrTy 1641Sema::HandleDeclarator(Scope *S, Declarator &D, 1642 MultiTemplateParamsArg TemplateParamLists, 1643 bool IsFunctionDefinition) { 1644 DeclarationName Name = GetNameForDeclarator(D); 1645 1646 // All of these full declarators require an identifier. If it doesn't have 1647 // one, the ParsedFreeStandingDeclSpec action should be used. 1648 if (!Name) { 1649 if (!D.isInvalidType()) // Reject this if we think it is valid. 1650 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1651 diag::err_declarator_need_ident) 1652 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1653 return DeclPtrTy(); 1654 } 1655 1656 // The scope passed in may not be a decl scope. Zip up the scope tree until 1657 // we find one that is. 1658 while ((S->getFlags() & Scope::DeclScope) == 0 || 1659 (S->getFlags() & Scope::TemplateParamScope) != 0) 1660 S = S->getParent(); 1661 1662 // If this is an out-of-line definition of a member of a class template 1663 // or class template partial specialization, we may need to rebuild the 1664 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1665 // for more information. 1666 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1667 // handle expressions properly. 1668 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1669 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1670 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1671 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1672 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1673 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1674 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1675 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1676 // FIXME: Preserve type source info. 1677 QualType T = GetTypeFromParser(DS.getTypeRep()); 1678 EnterDeclaratorContext(S, DC); 1679 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1680 ExitDeclaratorContext(S); 1681 if (T.isNull()) 1682 return DeclPtrTy(); 1683 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1684 } 1685 } 1686 1687 DeclContext *DC; 1688 NamedDecl *PrevDecl; 1689 NamedDecl *New; 1690 1691 DeclaratorInfo *DInfo = 0; 1692 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1693 1694 // See if this is a redefinition of a variable in the same scope. 1695 if (D.getCXXScopeSpec().isInvalid()) { 1696 DC = CurContext; 1697 PrevDecl = 0; 1698 D.setInvalidType(); 1699 } else if (!D.getCXXScopeSpec().isSet()) { 1700 LookupNameKind NameKind = LookupOrdinaryName; 1701 1702 // If the declaration we're planning to build will be a function 1703 // or object with linkage, then look for another declaration with 1704 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1705 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1706 /* Do nothing*/; 1707 else if (R->isFunctionType()) { 1708 if (CurContext->isFunctionOrMethod() || 1709 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1710 NameKind = LookupRedeclarationWithLinkage; 1711 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1712 NameKind = LookupRedeclarationWithLinkage; 1713 else if (CurContext->getLookupContext()->isTranslationUnit() && 1714 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1715 NameKind = LookupRedeclarationWithLinkage; 1716 1717 DC = CurContext; 1718 LookupResult R; 1719 LookupName(R, S, Name, NameKind, true, 1720 NameKind == LookupRedeclarationWithLinkage, 1721 D.getIdentifierLoc()); 1722 PrevDecl = R.getAsSingleDecl(Context); 1723 } else { // Something like "int foo::x;" 1724 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1725 1726 if (!DC) { 1727 // If we could not compute the declaration context, it's because the 1728 // declaration context is dependent but does not refer to a class, 1729 // class template, or class template partial specialization. Complain 1730 // and return early, to avoid the coming semantic disaster. 1731 Diag(D.getIdentifierLoc(), 1732 diag::err_template_qualified_declarator_no_match) 1733 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1734 << D.getCXXScopeSpec().getRange(); 1735 return DeclPtrTy(); 1736 } 1737 1738 if (!DC->isDependentContext() && 1739 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1740 return DeclPtrTy(); 1741 1742 LookupResult Res; 1743 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1744 PrevDecl = Res.getAsSingleDecl(Context); 1745 1746 // C++ 7.3.1.2p2: 1747 // Members (including explicit specializations of templates) of a named 1748 // namespace can also be defined outside that namespace by explicit 1749 // qualification of the name being defined, provided that the entity being 1750 // defined was already declared in the namespace and the definition appears 1751 // after the point of declaration in a namespace that encloses the 1752 // declarations namespace. 1753 // 1754 // Note that we only check the context at this point. We don't yet 1755 // have enough information to make sure that PrevDecl is actually 1756 // the declaration we want to match. For example, given: 1757 // 1758 // class X { 1759 // void f(); 1760 // void f(float); 1761 // }; 1762 // 1763 // void X::f(int) { } // ill-formed 1764 // 1765 // In this case, PrevDecl will point to the overload set 1766 // containing the two f's declared in X, but neither of them 1767 // matches. 1768 1769 // First check whether we named the global scope. 1770 if (isa<TranslationUnitDecl>(DC)) { 1771 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1772 << Name << D.getCXXScopeSpec().getRange(); 1773 } else if (!CurContext->Encloses(DC)) { 1774 // The qualifying scope doesn't enclose the original declaration. 1775 // Emit diagnostic based on current scope. 1776 SourceLocation L = D.getIdentifierLoc(); 1777 SourceRange R = D.getCXXScopeSpec().getRange(); 1778 if (isa<FunctionDecl>(CurContext)) 1779 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1780 else 1781 Diag(L, diag::err_invalid_declarator_scope) 1782 << Name << cast<NamedDecl>(DC) << R; 1783 D.setInvalidType(); 1784 } 1785 } 1786 1787 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1788 // Maybe we will complain about the shadowed template parameter. 1789 if (!D.isInvalidType()) 1790 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1791 D.setInvalidType(); 1792 1793 // Just pretend that we didn't see the previous declaration. 1794 PrevDecl = 0; 1795 } 1796 1797 // In C++, the previous declaration we find might be a tag type 1798 // (class or enum). In this case, the new declaration will hide the 1799 // tag type. Note that this does does not apply if we're declaring a 1800 // typedef (C++ [dcl.typedef]p4). 1801 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1802 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1803 PrevDecl = 0; 1804 1805 bool Redeclaration = false; 1806 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1807 if (TemplateParamLists.size()) { 1808 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1809 return DeclPtrTy(); 1810 } 1811 1812 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1813 } else if (R->isFunctionType()) { 1814 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1815 move(TemplateParamLists), 1816 IsFunctionDefinition, Redeclaration); 1817 } else { 1818 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1819 move(TemplateParamLists), 1820 Redeclaration); 1821 } 1822 1823 if (New == 0) 1824 return DeclPtrTy(); 1825 1826 // If this has an identifier and is not an invalid redeclaration or 1827 // function template specialization, add it to the scope stack. 1828 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1829 !(isa<FunctionDecl>(New) && 1830 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1831 PushOnScopeChains(New, S); 1832 1833 return DeclPtrTy::make(New); 1834} 1835 1836/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1837/// types into constant array types in certain situations which would otherwise 1838/// be errors (for GCC compatibility). 1839static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1840 ASTContext &Context, 1841 bool &SizeIsNegative) { 1842 // This method tries to turn a variable array into a constant 1843 // array even when the size isn't an ICE. This is necessary 1844 // for compatibility with code that depends on gcc's buggy 1845 // constant expression folding, like struct {char x[(int)(char*)2];} 1846 SizeIsNegative = false; 1847 1848 QualifierCollector Qs; 1849 const Type *Ty = Qs.strip(T); 1850 1851 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1852 QualType Pointee = PTy->getPointeeType(); 1853 QualType FixedType = 1854 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1855 if (FixedType.isNull()) return FixedType; 1856 FixedType = Context.getPointerType(FixedType); 1857 return Qs.apply(FixedType); 1858 } 1859 1860 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1861 if (!VLATy) 1862 return QualType(); 1863 // FIXME: We should probably handle this case 1864 if (VLATy->getElementType()->isVariablyModifiedType()) 1865 return QualType(); 1866 1867 Expr::EvalResult EvalResult; 1868 if (!VLATy->getSizeExpr() || 1869 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1870 !EvalResult.Val.isInt()) 1871 return QualType(); 1872 1873 llvm::APSInt &Res = EvalResult.Val.getInt(); 1874 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1875 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1876 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1877 // so as to transfer ownership to the ConstantArrayWithExpr. 1878 // Alternatively, we could "clone" it (how?). 1879 // Since we don't know how to do things above, we just use the 1880 // very same Expr*. 1881 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1882 Res, ArySizeExpr, 1883 ArrayType::Normal, 0, 1884 VLATy->getBracketsRange()); 1885 } 1886 1887 SizeIsNegative = true; 1888 return QualType(); 1889} 1890 1891/// \brief Register the given locally-scoped external C declaration so 1892/// that it can be found later for redeclarations 1893void 1894Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1895 Scope *S) { 1896 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1897 "Decl is not a locally-scoped decl!"); 1898 // Note that we have a locally-scoped external with this name. 1899 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1900 1901 if (!PrevDecl) 1902 return; 1903 1904 // If there was a previous declaration of this variable, it may be 1905 // in our identifier chain. Update the identifier chain with the new 1906 // declaration. 1907 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1908 // The previous declaration was found on the identifer resolver 1909 // chain, so remove it from its scope. 1910 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1911 S = S->getParent(); 1912 1913 if (S) 1914 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1915 } 1916} 1917 1918/// \brief Diagnose function specifiers on a declaration of an identifier that 1919/// does not identify a function. 1920void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1921 // FIXME: We should probably indicate the identifier in question to avoid 1922 // confusion for constructs like "inline int a(), b;" 1923 if (D.getDeclSpec().isInlineSpecified()) 1924 Diag(D.getDeclSpec().getInlineSpecLoc(), 1925 diag::err_inline_non_function); 1926 1927 if (D.getDeclSpec().isVirtualSpecified()) 1928 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1929 diag::err_virtual_non_function); 1930 1931 if (D.getDeclSpec().isExplicitSpecified()) 1932 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1933 diag::err_explicit_non_function); 1934} 1935 1936NamedDecl* 1937Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1938 QualType R, DeclaratorInfo *DInfo, 1939 NamedDecl* PrevDecl, bool &Redeclaration) { 1940 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1941 if (D.getCXXScopeSpec().isSet()) { 1942 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1943 << D.getCXXScopeSpec().getRange(); 1944 D.setInvalidType(); 1945 // Pretend we didn't see the scope specifier. 1946 DC = 0; 1947 } 1948 1949 if (getLangOptions().CPlusPlus) { 1950 // Check that there are no default arguments (C++ only). 1951 CheckExtraCXXDefaultArguments(D); 1952 } 1953 1954 DiagnoseFunctionSpecifiers(D); 1955 1956 if (D.getDeclSpec().isThreadSpecified()) 1957 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1958 1959 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1960 if (!NewTD) return 0; 1961 1962 if (D.isInvalidType()) 1963 NewTD->setInvalidDecl(); 1964 1965 // Handle attributes prior to checking for duplicates in MergeVarDecl 1966 ProcessDeclAttributes(S, NewTD, D); 1967 // Merge the decl with the existing one if appropriate. If the decl is 1968 // in an outer scope, it isn't the same thing. 1969 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1970 Redeclaration = true; 1971 MergeTypeDefDecl(NewTD, PrevDecl); 1972 } 1973 1974 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1975 // then it shall have block scope. 1976 QualType T = NewTD->getUnderlyingType(); 1977 if (T->isVariablyModifiedType()) { 1978 CurFunctionNeedsScopeChecking = true; 1979 1980 if (S->getFnParent() == 0) { 1981 bool SizeIsNegative; 1982 QualType FixedTy = 1983 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1984 if (!FixedTy.isNull()) { 1985 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1986 NewTD->setUnderlyingType(FixedTy); 1987 } else { 1988 if (SizeIsNegative) 1989 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1990 else if (T->isVariableArrayType()) 1991 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1992 else 1993 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1994 NewTD->setInvalidDecl(); 1995 } 1996 } 1997 } 1998 1999 // If this is the C FILE type, notify the AST context. 2000 if (IdentifierInfo *II = NewTD->getIdentifier()) 2001 if (!NewTD->isInvalidDecl() && 2002 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2003 if (II->isStr("FILE")) 2004 Context.setFILEDecl(NewTD); 2005 else if (II->isStr("jmp_buf")) 2006 Context.setjmp_bufDecl(NewTD); 2007 else if (II->isStr("sigjmp_buf")) 2008 Context.setsigjmp_bufDecl(NewTD); 2009 } 2010 2011 return NewTD; 2012} 2013 2014/// \brief Determines whether the given declaration is an out-of-scope 2015/// previous declaration. 2016/// 2017/// This routine should be invoked when name lookup has found a 2018/// previous declaration (PrevDecl) that is not in the scope where a 2019/// new declaration by the same name is being introduced. If the new 2020/// declaration occurs in a local scope, previous declarations with 2021/// linkage may still be considered previous declarations (C99 2022/// 6.2.2p4-5, C++ [basic.link]p6). 2023/// 2024/// \param PrevDecl the previous declaration found by name 2025/// lookup 2026/// 2027/// \param DC the context in which the new declaration is being 2028/// declared. 2029/// 2030/// \returns true if PrevDecl is an out-of-scope previous declaration 2031/// for a new delcaration with the same name. 2032static bool 2033isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2034 ASTContext &Context) { 2035 if (!PrevDecl) 2036 return 0; 2037 2038 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2039 // case we need to check each of the overloaded functions. 2040 if (!PrevDecl->hasLinkage()) 2041 return false; 2042 2043 if (Context.getLangOptions().CPlusPlus) { 2044 // C++ [basic.link]p6: 2045 // If there is a visible declaration of an entity with linkage 2046 // having the same name and type, ignoring entities declared 2047 // outside the innermost enclosing namespace scope, the block 2048 // scope declaration declares that same entity and receives the 2049 // linkage of the previous declaration. 2050 DeclContext *OuterContext = DC->getLookupContext(); 2051 if (!OuterContext->isFunctionOrMethod()) 2052 // This rule only applies to block-scope declarations. 2053 return false; 2054 else { 2055 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2056 if (PrevOuterContext->isRecord()) 2057 // We found a member function: ignore it. 2058 return false; 2059 else { 2060 // Find the innermost enclosing namespace for the new and 2061 // previous declarations. 2062 while (!OuterContext->isFileContext()) 2063 OuterContext = OuterContext->getParent(); 2064 while (!PrevOuterContext->isFileContext()) 2065 PrevOuterContext = PrevOuterContext->getParent(); 2066 2067 // The previous declaration is in a different namespace, so it 2068 // isn't the same function. 2069 if (OuterContext->getPrimaryContext() != 2070 PrevOuterContext->getPrimaryContext()) 2071 return false; 2072 } 2073 } 2074 } 2075 2076 return true; 2077} 2078 2079NamedDecl* 2080Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2081 QualType R, DeclaratorInfo *DInfo, 2082 NamedDecl* PrevDecl, 2083 MultiTemplateParamsArg TemplateParamLists, 2084 bool &Redeclaration) { 2085 DeclarationName Name = GetNameForDeclarator(D); 2086 2087 // Check that there are no default arguments (C++ only). 2088 if (getLangOptions().CPlusPlus) 2089 CheckExtraCXXDefaultArguments(D); 2090 2091 VarDecl *NewVD; 2092 VarDecl::StorageClass SC; 2093 switch (D.getDeclSpec().getStorageClassSpec()) { 2094 default: assert(0 && "Unknown storage class!"); 2095 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2096 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2097 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2098 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2099 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2100 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2101 case DeclSpec::SCS_mutable: 2102 // mutable can only appear on non-static class members, so it's always 2103 // an error here 2104 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2105 D.setInvalidType(); 2106 SC = VarDecl::None; 2107 break; 2108 } 2109 2110 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2111 if (!II) { 2112 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2113 << Name.getAsString(); 2114 return 0; 2115 } 2116 2117 DiagnoseFunctionSpecifiers(D); 2118 2119 if (!DC->isRecord() && S->getFnParent() == 0) { 2120 // C99 6.9p2: The storage-class specifiers auto and register shall not 2121 // appear in the declaration specifiers in an external declaration. 2122 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2123 2124 // If this is a register variable with an asm label specified, then this 2125 // is a GNU extension. 2126 if (SC == VarDecl::Register && D.getAsmLabel()) 2127 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2128 else 2129 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2130 D.setInvalidType(); 2131 } 2132 } 2133 if (DC->isRecord() && !CurContext->isRecord()) { 2134 // This is an out-of-line definition of a static data member. 2135 if (SC == VarDecl::Static) { 2136 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2137 diag::err_static_out_of_line) 2138 << CodeModificationHint::CreateRemoval( 2139 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2140 } else if (SC == VarDecl::None) 2141 SC = VarDecl::Static; 2142 } 2143 if (SC == VarDecl::Static) { 2144 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2145 if (RD->isLocalClass()) 2146 Diag(D.getIdentifierLoc(), 2147 diag::err_static_data_member_not_allowed_in_local_class) 2148 << Name << RD->getDeclName(); 2149 } 2150 } 2151 2152 // Match up the template parameter lists with the scope specifier, then 2153 // determine whether we have a template or a template specialization. 2154 bool isExplicitSpecialization = false; 2155 if (TemplateParameterList *TemplateParams 2156 = MatchTemplateParametersToScopeSpecifier( 2157 D.getDeclSpec().getSourceRange().getBegin(), 2158 D.getCXXScopeSpec(), 2159 (TemplateParameterList**)TemplateParamLists.get(), 2160 TemplateParamLists.size(), 2161 isExplicitSpecialization)) { 2162 if (TemplateParams->size() > 0) { 2163 // There is no such thing as a variable template. 2164 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2165 << II 2166 << SourceRange(TemplateParams->getTemplateLoc(), 2167 TemplateParams->getRAngleLoc()); 2168 return 0; 2169 } else { 2170 // There is an extraneous 'template<>' for this variable. Complain 2171 // about it, but allow the declaration of the variable. 2172 Diag(TemplateParams->getTemplateLoc(), 2173 diag::err_template_variable_noparams) 2174 << II 2175 << SourceRange(TemplateParams->getTemplateLoc(), 2176 TemplateParams->getRAngleLoc()); 2177 2178 isExplicitSpecialization = true; 2179 } 2180 } 2181 2182 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2183 II, R, DInfo, SC); 2184 2185 if (D.isInvalidType()) 2186 NewVD->setInvalidDecl(); 2187 2188 if (D.getDeclSpec().isThreadSpecified()) { 2189 if (NewVD->hasLocalStorage()) 2190 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2191 else if (!Context.Target.isTLSSupported()) 2192 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2193 else 2194 NewVD->setThreadSpecified(true); 2195 } 2196 2197 // Set the lexical context. If the declarator has a C++ scope specifier, the 2198 // lexical context will be different from the semantic context. 2199 NewVD->setLexicalDeclContext(CurContext); 2200 2201 // Handle attributes prior to checking for duplicates in MergeVarDecl 2202 ProcessDeclAttributes(S, NewVD, D); 2203 2204 // Handle GNU asm-label extension (encoded as an attribute). 2205 if (Expr *E = (Expr*) D.getAsmLabel()) { 2206 // The parser guarantees this is a string. 2207 StringLiteral *SE = cast<StringLiteral>(E); 2208 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2209 SE->getByteLength()))); 2210 } 2211 2212 // If name lookup finds a previous declaration that is not in the 2213 // same scope as the new declaration, this may still be an 2214 // acceptable redeclaration. 2215 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2216 !(NewVD->hasLinkage() && 2217 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2218 PrevDecl = 0; 2219 2220 // Merge the decl with the existing one if appropriate. 2221 if (PrevDecl) { 2222 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2223 // The user tried to define a non-static data member 2224 // out-of-line (C++ [dcl.meaning]p1). 2225 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2226 << D.getCXXScopeSpec().getRange(); 2227 PrevDecl = 0; 2228 NewVD->setInvalidDecl(); 2229 } 2230 } else if (D.getCXXScopeSpec().isSet()) { 2231 // No previous declaration in the qualifying scope. 2232 Diag(D.getIdentifierLoc(), diag::err_no_member) 2233 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2234 << D.getCXXScopeSpec().getRange(); 2235 NewVD->setInvalidDecl(); 2236 } 2237 2238 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2239 2240 // This is an explicit specialization of a static data member. Check it. 2241 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2242 CheckMemberSpecialization(NewVD, PrevDecl)) 2243 NewVD->setInvalidDecl(); 2244 2245 // attributes declared post-definition are currently ignored 2246 if (PrevDecl) { 2247 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2248 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2249 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2250 Diag(Def->getLocation(), diag::note_previous_definition); 2251 } 2252 } 2253 2254 // If this is a locally-scoped extern C variable, update the map of 2255 // such variables. 2256 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2257 !NewVD->isInvalidDecl()) 2258 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2259 2260 return NewVD; 2261} 2262 2263/// \brief Perform semantic checking on a newly-created variable 2264/// declaration. 2265/// 2266/// This routine performs all of the type-checking required for a 2267/// variable declaration once it has been built. It is used both to 2268/// check variables after they have been parsed and their declarators 2269/// have been translated into a declaration, and to check variables 2270/// that have been instantiated from a template. 2271/// 2272/// Sets NewVD->isInvalidDecl() if an error was encountered. 2273void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2274 bool &Redeclaration) { 2275 // If the decl is already known invalid, don't check it. 2276 if (NewVD->isInvalidDecl()) 2277 return; 2278 2279 QualType T = NewVD->getType(); 2280 2281 if (T->isObjCInterfaceType()) { 2282 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2283 return NewVD->setInvalidDecl(); 2284 } 2285 2286 // The variable can not have an abstract class type. 2287 if (RequireNonAbstractType(NewVD->getLocation(), T, 2288 diag::err_abstract_type_in_decl, 2289 AbstractVariableType)) 2290 return NewVD->setInvalidDecl(); 2291 2292 // Emit an error if an address space was applied to decl with local storage. 2293 // This includes arrays of objects with address space qualifiers, but not 2294 // automatic variables that point to other address spaces. 2295 // ISO/IEC TR 18037 S5.1.2 2296 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2297 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2298 return NewVD->setInvalidDecl(); 2299 } 2300 2301 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2302 && !NewVD->hasAttr<BlocksAttr>()) 2303 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2304 2305 bool isVM = T->isVariablyModifiedType(); 2306 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2307 NewVD->hasAttr<BlocksAttr>()) 2308 CurFunctionNeedsScopeChecking = true; 2309 2310 if ((isVM && NewVD->hasLinkage()) || 2311 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2312 bool SizeIsNegative; 2313 QualType FixedTy = 2314 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2315 2316 if (FixedTy.isNull() && T->isVariableArrayType()) { 2317 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2318 // FIXME: This won't give the correct result for 2319 // int a[10][n]; 2320 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2321 2322 if (NewVD->isFileVarDecl()) 2323 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2324 << SizeRange; 2325 else if (NewVD->getStorageClass() == VarDecl::Static) 2326 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2327 << SizeRange; 2328 else 2329 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2330 << SizeRange; 2331 return NewVD->setInvalidDecl(); 2332 } 2333 2334 if (FixedTy.isNull()) { 2335 if (NewVD->isFileVarDecl()) 2336 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2337 else 2338 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2339 return NewVD->setInvalidDecl(); 2340 } 2341 2342 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2343 NewVD->setType(FixedTy); 2344 } 2345 2346 if (!PrevDecl && NewVD->isExternC()) { 2347 // Since we did not find anything by this name and we're declaring 2348 // an extern "C" variable, look for a non-visible extern "C" 2349 // declaration with the same name. 2350 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2351 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2352 if (Pos != LocallyScopedExternalDecls.end()) 2353 PrevDecl = Pos->second; 2354 } 2355 2356 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2357 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2358 << T; 2359 return NewVD->setInvalidDecl(); 2360 } 2361 2362 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2363 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2364 return NewVD->setInvalidDecl(); 2365 } 2366 2367 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2368 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2369 return NewVD->setInvalidDecl(); 2370 } 2371 2372 if (PrevDecl) { 2373 Redeclaration = true; 2374 MergeVarDecl(NewVD, PrevDecl); 2375 } 2376} 2377 2378static bool isUsingDecl(Decl *D) { 2379 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2380} 2381 2382/// \brief Data used with FindOverriddenMethod 2383struct FindOverriddenMethodData { 2384 Sema *S; 2385 CXXMethodDecl *Method; 2386}; 2387 2388/// \brief Member lookup function that determines whether a given C++ 2389/// method overrides a method in a base class, to be used with 2390/// CXXRecordDecl::lookupInBases(). 2391static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2392 CXXBasePath &Path, 2393 void *UserData) { 2394 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2395 2396 FindOverriddenMethodData *Data 2397 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2398 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2399 Path.Decls.first != Path.Decls.second; 2400 ++Path.Decls.first) { 2401 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2402 OverloadedFunctionDecl::function_iterator MatchedDecl; 2403 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2404 return true; 2405 } 2406 } 2407 2408 return false; 2409} 2410 2411NamedDecl* 2412Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2413 QualType R, DeclaratorInfo *DInfo, 2414 NamedDecl* PrevDecl, 2415 MultiTemplateParamsArg TemplateParamLists, 2416 bool IsFunctionDefinition, bool &Redeclaration) { 2417 assert(R.getTypePtr()->isFunctionType()); 2418 2419 DeclarationName Name = GetNameForDeclarator(D); 2420 FunctionDecl::StorageClass SC = FunctionDecl::None; 2421 switch (D.getDeclSpec().getStorageClassSpec()) { 2422 default: assert(0 && "Unknown storage class!"); 2423 case DeclSpec::SCS_auto: 2424 case DeclSpec::SCS_register: 2425 case DeclSpec::SCS_mutable: 2426 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2427 diag::err_typecheck_sclass_func); 2428 D.setInvalidType(); 2429 break; 2430 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2431 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2432 case DeclSpec::SCS_static: { 2433 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2434 // C99 6.7.1p5: 2435 // The declaration of an identifier for a function that has 2436 // block scope shall have no explicit storage-class specifier 2437 // other than extern 2438 // See also (C++ [dcl.stc]p4). 2439 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2440 diag::err_static_block_func); 2441 SC = FunctionDecl::None; 2442 } else 2443 SC = FunctionDecl::Static; 2444 break; 2445 } 2446 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2447 } 2448 2449 if (D.getDeclSpec().isThreadSpecified()) 2450 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2451 2452 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2453 bool isInline = D.getDeclSpec().isInlineSpecified(); 2454 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2455 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2456 2457 // Check that the return type is not an abstract class type. 2458 // For record types, this is done by the AbstractClassUsageDiagnoser once 2459 // the class has been completely parsed. 2460 if (!DC->isRecord() && 2461 RequireNonAbstractType(D.getIdentifierLoc(), 2462 R->getAs<FunctionType>()->getResultType(), 2463 diag::err_abstract_type_in_decl, 2464 AbstractReturnType)) 2465 D.setInvalidType(); 2466 2467 // Do not allow returning a objc interface by-value. 2468 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2469 Diag(D.getIdentifierLoc(), 2470 diag::err_object_cannot_be_passed_returned_by_value) << 0 2471 << R->getAs<FunctionType>()->getResultType(); 2472 D.setInvalidType(); 2473 } 2474 2475 bool isVirtualOkay = false; 2476 FunctionDecl *NewFD; 2477 2478 if (isFriend) { 2479 // DC is the namespace in which the function is being declared. 2480 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2481 "friend function being created in a non-namespace context"); 2482 2483 // C++ [class.friend]p5 2484 // A function can be defined in a friend declaration of a 2485 // class . . . . Such a function is implicitly inline. 2486 isInline |= IsFunctionDefinition; 2487 } 2488 2489 if (D.getKind() == Declarator::DK_Constructor) { 2490 // This is a C++ constructor declaration. 2491 assert(DC->isRecord() && 2492 "Constructors can only be declared in a member context"); 2493 2494 R = CheckConstructorDeclarator(D, R, SC); 2495 2496 // Create the new declaration 2497 NewFD = CXXConstructorDecl::Create(Context, 2498 cast<CXXRecordDecl>(DC), 2499 D.getIdentifierLoc(), Name, R, DInfo, 2500 isExplicit, isInline, 2501 /*isImplicitlyDeclared=*/false); 2502 } else if (D.getKind() == Declarator::DK_Destructor) { 2503 // This is a C++ destructor declaration. 2504 if (DC->isRecord()) { 2505 R = CheckDestructorDeclarator(D, SC); 2506 2507 NewFD = CXXDestructorDecl::Create(Context, 2508 cast<CXXRecordDecl>(DC), 2509 D.getIdentifierLoc(), Name, R, 2510 isInline, 2511 /*isImplicitlyDeclared=*/false); 2512 2513 isVirtualOkay = true; 2514 } else { 2515 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2516 2517 // Create a FunctionDecl to satisfy the function definition parsing 2518 // code path. 2519 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2520 Name, R, DInfo, SC, isInline, 2521 /*hasPrototype=*/true); 2522 D.setInvalidType(); 2523 } 2524 } else if (D.getKind() == Declarator::DK_Conversion) { 2525 if (!DC->isRecord()) { 2526 Diag(D.getIdentifierLoc(), 2527 diag::err_conv_function_not_member); 2528 return 0; 2529 } 2530 2531 CheckConversionDeclarator(D, R, SC); 2532 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2533 D.getIdentifierLoc(), Name, R, DInfo, 2534 isInline, isExplicit); 2535 2536 isVirtualOkay = true; 2537 } else if (DC->isRecord()) { 2538 // If the of the function is the same as the name of the record, then this 2539 // must be an invalid constructor that has a return type. 2540 // (The parser checks for a return type and makes the declarator a 2541 // constructor if it has no return type). 2542 // must have an invalid constructor that has a return type 2543 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2544 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2545 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2546 << SourceRange(D.getIdentifierLoc()); 2547 return 0; 2548 } 2549 2550 // This is a C++ method declaration. 2551 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2552 D.getIdentifierLoc(), Name, R, DInfo, 2553 (SC == FunctionDecl::Static), isInline); 2554 2555 isVirtualOkay = (SC != FunctionDecl::Static); 2556 } else { 2557 // Determine whether the function was written with a 2558 // prototype. This true when: 2559 // - we're in C++ (where every function has a prototype), 2560 // - there is a prototype in the declarator, or 2561 // - the type R of the function is some kind of typedef or other reference 2562 // to a type name (which eventually refers to a function type). 2563 bool HasPrototype = 2564 getLangOptions().CPlusPlus || 2565 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2566 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2567 2568 NewFD = FunctionDecl::Create(Context, DC, 2569 D.getIdentifierLoc(), 2570 Name, R, DInfo, SC, isInline, HasPrototype); 2571 } 2572 2573 if (D.isInvalidType()) 2574 NewFD->setInvalidDecl(); 2575 2576 // Set the lexical context. If the declarator has a C++ 2577 // scope specifier, or is the object of a friend declaration, the 2578 // lexical context will be different from the semantic context. 2579 NewFD->setLexicalDeclContext(CurContext); 2580 2581 // Match up the template parameter lists with the scope specifier, then 2582 // determine whether we have a template or a template specialization. 2583 FunctionTemplateDecl *FunctionTemplate = 0; 2584 bool isExplicitSpecialization = false; 2585 bool isFunctionTemplateSpecialization = false; 2586 if (TemplateParameterList *TemplateParams 2587 = MatchTemplateParametersToScopeSpecifier( 2588 D.getDeclSpec().getSourceRange().getBegin(), 2589 D.getCXXScopeSpec(), 2590 (TemplateParameterList**)TemplateParamLists.get(), 2591 TemplateParamLists.size(), 2592 isExplicitSpecialization)) { 2593 if (TemplateParams->size() > 0) { 2594 // This is a function template 2595 2596 // Check that we can declare a template here. 2597 if (CheckTemplateDeclScope(S, TemplateParams)) 2598 return 0; 2599 2600 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2601 NewFD->getLocation(), 2602 Name, TemplateParams, 2603 NewFD); 2604 FunctionTemplate->setLexicalDeclContext(CurContext); 2605 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2606 } else { 2607 // This is a function template specialization. 2608 isFunctionTemplateSpecialization = true; 2609 } 2610 2611 // FIXME: Free this memory properly. 2612 TemplateParamLists.release(); 2613 } 2614 2615 // C++ [dcl.fct.spec]p5: 2616 // The virtual specifier shall only be used in declarations of 2617 // nonstatic class member functions that appear within a 2618 // member-specification of a class declaration; see 10.3. 2619 // 2620 if (isVirtual && !NewFD->isInvalidDecl()) { 2621 if (!isVirtualOkay) { 2622 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2623 diag::err_virtual_non_function); 2624 } else if (!CurContext->isRecord()) { 2625 // 'virtual' was specified outside of the class. 2626 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2627 << CodeModificationHint::CreateRemoval( 2628 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2629 } else { 2630 // Okay: Add virtual to the method. 2631 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2632 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2633 CurClass->setAggregate(false); 2634 CurClass->setPOD(false); 2635 CurClass->setEmpty(false); 2636 CurClass->setPolymorphic(true); 2637 CurClass->setHasTrivialConstructor(false); 2638 CurClass->setHasTrivialCopyConstructor(false); 2639 CurClass->setHasTrivialCopyAssignment(false); 2640 } 2641 } 2642 2643 if (isFriend) { 2644 if (FunctionTemplate) { 2645 FunctionTemplate->setObjectOfFriendDecl( 2646 /* PreviouslyDeclared= */ PrevDecl != NULL); 2647 FunctionTemplate->setAccess(AS_public); 2648 } 2649 else 2650 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2651 2652 NewFD->setAccess(AS_public); 2653 } 2654 2655 2656 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2657 // Look for virtual methods in base classes that this method might override. 2658 CXXBasePaths Paths; 2659 FindOverriddenMethodData Data; 2660 Data.Method = NewMD; 2661 Data.S = this; 2662 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2663 Paths)) { 2664 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2665 E = Paths.found_decls_end(); I != E; ++I) { 2666 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2667 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2668 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2669 NewMD->addOverriddenMethod(OldMD); 2670 } 2671 } 2672 } 2673 } 2674 2675 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2676 !CurContext->isRecord()) { 2677 // C++ [class.static]p1: 2678 // A data or function member of a class may be declared static 2679 // in a class definition, in which case it is a static member of 2680 // the class. 2681 2682 // Complain about the 'static' specifier if it's on an out-of-line 2683 // member function definition. 2684 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2685 diag::err_static_out_of_line) 2686 << CodeModificationHint::CreateRemoval( 2687 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2688 } 2689 2690 // Handle GNU asm-label extension (encoded as an attribute). 2691 if (Expr *E = (Expr*) D.getAsmLabel()) { 2692 // The parser guarantees this is a string. 2693 StringLiteral *SE = cast<StringLiteral>(E); 2694 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2695 SE->getByteLength()))); 2696 } 2697 2698 // Copy the parameter declarations from the declarator D to the function 2699 // declaration NewFD, if they are available. First scavenge them into Params. 2700 llvm::SmallVector<ParmVarDecl*, 16> Params; 2701 if (D.getNumTypeObjects() > 0) { 2702 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2703 2704 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2705 // function that takes no arguments, not a function that takes a 2706 // single void argument. 2707 // We let through "const void" here because Sema::GetTypeForDeclarator 2708 // already checks for that case. 2709 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2710 FTI.ArgInfo[0].Param && 2711 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2712 // Empty arg list, don't push any params. 2713 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2714 2715 // In C++, the empty parameter-type-list must be spelled "void"; a 2716 // typedef of void is not permitted. 2717 if (getLangOptions().CPlusPlus && 2718 Param->getType().getUnqualifiedType() != Context.VoidTy) 2719 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2720 // FIXME: Leaks decl? 2721 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2722 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2723 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2724 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2725 Param->setDeclContext(NewFD); 2726 Params.push_back(Param); 2727 } 2728 } 2729 2730 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2731 // When we're declaring a function with a typedef, typeof, etc as in the 2732 // following example, we'll need to synthesize (unnamed) 2733 // parameters for use in the declaration. 2734 // 2735 // @code 2736 // typedef void fn(int); 2737 // fn f; 2738 // @endcode 2739 2740 // Synthesize a parameter for each argument type. 2741 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2742 AE = FT->arg_type_end(); AI != AE; ++AI) { 2743 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2744 SourceLocation(), 0, 2745 *AI, /*DInfo=*/0, 2746 VarDecl::None, 0); 2747 Param->setImplicit(); 2748 Params.push_back(Param); 2749 } 2750 } else { 2751 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2752 "Should not need args for typedef of non-prototype fn"); 2753 } 2754 // Finally, we know we have the right number of parameters, install them. 2755 NewFD->setParams(Context, Params.data(), Params.size()); 2756 2757 // If name lookup finds a previous declaration that is not in the 2758 // same scope as the new declaration, this may still be an 2759 // acceptable redeclaration. 2760 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2761 !(NewFD->hasLinkage() && 2762 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2763 PrevDecl = 0; 2764 2765 // If the declarator is a template-id, translate the parser's template 2766 // argument list into our AST format. 2767 bool HasExplicitTemplateArgs = false; 2768 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2769 SourceLocation LAngleLoc, RAngleLoc; 2770 if (D.getKind() == Declarator::DK_TemplateId) { 2771 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2772 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2773 TemplateId->getTemplateArgs(), 2774 TemplateId->getTemplateArgIsType(), 2775 TemplateId->NumArgs); 2776 translateTemplateArguments(TemplateArgsPtr, 2777 TemplateId->getTemplateArgLocations(), 2778 TemplateArgs); 2779 TemplateArgsPtr.release(); 2780 2781 HasExplicitTemplateArgs = true; 2782 LAngleLoc = TemplateId->LAngleLoc; 2783 RAngleLoc = TemplateId->RAngleLoc; 2784 2785 if (FunctionTemplate) { 2786 // FIXME: Diagnose function template with explicit template 2787 // arguments. 2788 HasExplicitTemplateArgs = false; 2789 } else if (!isFunctionTemplateSpecialization && 2790 !D.getDeclSpec().isFriendSpecified()) { 2791 // We have encountered something that the user meant to be a 2792 // specialization (because it has explicitly-specified template 2793 // arguments) but that was not introduced with a "template<>" (or had 2794 // too few of them). 2795 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2796 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2797 << CodeModificationHint::CreateInsertion( 2798 D.getDeclSpec().getSourceRange().getBegin(), 2799 "template<> "); 2800 isFunctionTemplateSpecialization = true; 2801 } 2802 } 2803 2804 if (isFunctionTemplateSpecialization) { 2805 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2806 LAngleLoc, TemplateArgs.data(), 2807 TemplateArgs.size(), RAngleLoc, 2808 PrevDecl)) 2809 NewFD->setInvalidDecl(); 2810 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2811 CheckMemberSpecialization(NewFD, PrevDecl)) 2812 NewFD->setInvalidDecl(); 2813 2814 // Perform semantic checking on the function declaration. 2815 bool OverloadableAttrRequired = false; // FIXME: HACK! 2816 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2817 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2818 2819 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2820 // An out-of-line member function declaration must also be a 2821 // definition (C++ [dcl.meaning]p1). 2822 // Note that this is not the case for explicit specializations of 2823 // function templates or member functions of class templates, per 2824 // C++ [temp.expl.spec]p2. 2825 if (!IsFunctionDefinition && !isFriend && 2826 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2827 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2828 << D.getCXXScopeSpec().getRange(); 2829 NewFD->setInvalidDecl(); 2830 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2831 // The user tried to provide an out-of-line definition for a 2832 // function that is a member of a class or namespace, but there 2833 // was no such member function declared (C++ [class.mfct]p2, 2834 // C++ [namespace.memdef]p2). For example: 2835 // 2836 // class X { 2837 // void f() const; 2838 // }; 2839 // 2840 // void X::f() { } // ill-formed 2841 // 2842 // Complain about this problem, and attempt to suggest close 2843 // matches (e.g., those that differ only in cv-qualifiers and 2844 // whether the parameter types are references). 2845 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2846 << Name << DC << D.getCXXScopeSpec().getRange(); 2847 NewFD->setInvalidDecl(); 2848 2849 LookupResult Prev; 2850 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2851 assert(!Prev.isAmbiguous() && 2852 "Cannot have an ambiguity in previous-declaration lookup"); 2853 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2854 Func != FuncEnd; ++Func) { 2855 if (isa<FunctionDecl>(*Func) && 2856 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2857 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2858 } 2859 2860 PrevDecl = 0; 2861 } 2862 } 2863 2864 // Handle attributes. We need to have merged decls when handling attributes 2865 // (for example to check for conflicts, etc). 2866 // FIXME: This needs to happen before we merge declarations. Then, 2867 // let attribute merging cope with attribute conflicts. 2868 ProcessDeclAttributes(S, NewFD, D); 2869 2870 // attributes declared post-definition are currently ignored 2871 if (Redeclaration && PrevDecl) { 2872 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2873 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2874 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2875 Diag(Def->getLocation(), diag::note_previous_definition); 2876 } 2877 } 2878 2879 AddKnownFunctionAttributes(NewFD); 2880 2881 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2882 // If a function name is overloadable in C, then every function 2883 // with that name must be marked "overloadable". 2884 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2885 << Redeclaration << NewFD; 2886 if (PrevDecl) 2887 Diag(PrevDecl->getLocation(), 2888 diag::note_attribute_overloadable_prev_overload); 2889 NewFD->addAttr(::new (Context) OverloadableAttr()); 2890 } 2891 2892 // If this is a locally-scoped extern C function, update the 2893 // map of such names. 2894 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2895 && !NewFD->isInvalidDecl()) 2896 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2897 2898 // Set this FunctionDecl's range up to the right paren. 2899 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2900 2901 if (FunctionTemplate && NewFD->isInvalidDecl()) 2902 FunctionTemplate->setInvalidDecl(); 2903 2904 if (FunctionTemplate) 2905 return FunctionTemplate; 2906 2907 return NewFD; 2908} 2909 2910/// \brief Perform semantic checking of a new function declaration. 2911/// 2912/// Performs semantic analysis of the new function declaration 2913/// NewFD. This routine performs all semantic checking that does not 2914/// require the actual declarator involved in the declaration, and is 2915/// used both for the declaration of functions as they are parsed 2916/// (called via ActOnDeclarator) and for the declaration of functions 2917/// that have been instantiated via C++ template instantiation (called 2918/// via InstantiateDecl). 2919/// 2920/// \param IsExplicitSpecialiation whether this new function declaration is 2921/// an explicit specialization of the previous declaration. 2922/// 2923/// This sets NewFD->isInvalidDecl() to true if there was an error. 2924void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2925 bool IsExplicitSpecialization, 2926 bool &Redeclaration, 2927 bool &OverloadableAttrRequired) { 2928 // If NewFD is already known erroneous, don't do any of this checking. 2929 if (NewFD->isInvalidDecl()) 2930 return; 2931 2932 if (NewFD->getResultType()->isVariablyModifiedType()) { 2933 // Functions returning a variably modified type violate C99 6.7.5.2p2 2934 // because all functions have linkage. 2935 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2936 return NewFD->setInvalidDecl(); 2937 } 2938 2939 if (NewFD->isMain()) 2940 CheckMain(NewFD); 2941 2942 // Check for a previous declaration of this name. 2943 if (!PrevDecl && NewFD->isExternC()) { 2944 // Since we did not find anything by this name and we're declaring 2945 // an extern "C" function, look for a non-visible extern "C" 2946 // declaration with the same name. 2947 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2948 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2949 if (Pos != LocallyScopedExternalDecls.end()) 2950 PrevDecl = Pos->second; 2951 } 2952 2953 // Merge or overload the declaration with an existing declaration of 2954 // the same name, if appropriate. 2955 if (PrevDecl) { 2956 // Determine whether NewFD is an overload of PrevDecl or 2957 // a declaration that requires merging. If it's an overload, 2958 // there's no more work to do here; we'll just add the new 2959 // function to the scope. 2960 OverloadedFunctionDecl::function_iterator MatchedDecl; 2961 2962 if (!getLangOptions().CPlusPlus && 2963 AllowOverloadingOfFunction(PrevDecl, Context)) { 2964 OverloadableAttrRequired = true; 2965 2966 // Functions marked "overloadable" must have a prototype (that 2967 // we can't get through declaration merging). 2968 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2969 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2970 << NewFD; 2971 Redeclaration = true; 2972 2973 // Turn this into a variadic function with no parameters. 2974 QualType R = Context.getFunctionType( 2975 NewFD->getType()->getAs<FunctionType>()->getResultType(), 2976 0, 0, true, 0); 2977 NewFD->setType(R); 2978 return NewFD->setInvalidDecl(); 2979 } 2980 } 2981 2982 if (PrevDecl && 2983 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2984 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2985 Redeclaration = true; 2986 Decl *OldDecl = PrevDecl; 2987 2988 // If PrevDecl was an overloaded function, extract the 2989 // FunctionDecl that matched. 2990 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2991 OldDecl = *MatchedDecl; 2992 2993 // NewFD and OldDecl represent declarations that need to be 2994 // merged. 2995 if (MergeFunctionDecl(NewFD, OldDecl)) 2996 return NewFD->setInvalidDecl(); 2997 2998 if (FunctionTemplateDecl *OldTemplateDecl 2999 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3000 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3001 FunctionTemplateDecl *NewTemplateDecl 3002 = NewFD->getDescribedFunctionTemplate(); 3003 assert(NewTemplateDecl && "Template/non-template mismatch"); 3004 if (CXXMethodDecl *Method 3005 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3006 Method->setAccess(OldTemplateDecl->getAccess()); 3007 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3008 } 3009 3010 // If this is an explicit specialization of a member that is a function 3011 // template, mark it as a member specialization. 3012 if (IsExplicitSpecialization && 3013 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3014 NewTemplateDecl->setMemberSpecialization(); 3015 assert(OldTemplateDecl->isMemberSpecialization()); 3016 } 3017 } else { 3018 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3019 NewFD->setAccess(OldDecl->getAccess()); 3020 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3021 } 3022 } 3023 } 3024 3025 // Semantic checking for this function declaration (in isolation). 3026 if (getLangOptions().CPlusPlus) { 3027 // C++-specific checks. 3028 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3029 CheckConstructor(Constructor); 3030 } else if (isa<CXXDestructorDecl>(NewFD)) { 3031 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3032 QualType ClassType = Context.getTypeDeclType(Record); 3033 if (!ClassType->isDependentType()) { 3034 DeclarationName Name 3035 = Context.DeclarationNames.getCXXDestructorName( 3036 Context.getCanonicalType(ClassType)); 3037 if (NewFD->getDeclName() != Name) { 3038 Diag(NewFD->getLocation(), diag::err_destructor_name); 3039 return NewFD->setInvalidDecl(); 3040 } 3041 } 3042 Record->setUserDeclaredDestructor(true); 3043 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3044 // user-defined destructor. 3045 Record->setPOD(false); 3046 3047 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3048 // declared destructor. 3049 // FIXME: C++0x: don't do this for "= default" destructors 3050 Record->setHasTrivialDestructor(false); 3051 } else if (CXXConversionDecl *Conversion 3052 = dyn_cast<CXXConversionDecl>(NewFD)) 3053 ActOnConversionDeclarator(Conversion); 3054 3055 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3056 if (NewFD->isOverloadedOperator() && 3057 CheckOverloadedOperatorDeclaration(NewFD)) 3058 return NewFD->setInvalidDecl(); 3059 3060 // In C++, check default arguments now that we have merged decls. Unless 3061 // the lexical context is the class, because in this case this is done 3062 // during delayed parsing anyway. 3063 if (!CurContext->isRecord()) 3064 CheckCXXDefaultArguments(NewFD); 3065 } 3066} 3067 3068void Sema::CheckMain(FunctionDecl* FD) { 3069 // C++ [basic.start.main]p3: A program that declares main to be inline 3070 // or static is ill-formed. 3071 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3072 // shall not appear in a declaration of main. 3073 // static main is not an error under C99, but we should warn about it. 3074 bool isInline = FD->isInline(); 3075 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3076 if (isInline || isStatic) { 3077 unsigned diagID = diag::warn_unusual_main_decl; 3078 if (isInline || getLangOptions().CPlusPlus) 3079 diagID = diag::err_unusual_main_decl; 3080 3081 int which = isStatic + (isInline << 1) - 1; 3082 Diag(FD->getLocation(), diagID) << which; 3083 } 3084 3085 QualType T = FD->getType(); 3086 assert(T->isFunctionType() && "function decl is not of function type"); 3087 const FunctionType* FT = T->getAs<FunctionType>(); 3088 3089 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3090 // TODO: add a replacement fixit to turn the return type into 'int'. 3091 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3092 FD->setInvalidDecl(true); 3093 } 3094 3095 // Treat protoless main() as nullary. 3096 if (isa<FunctionNoProtoType>(FT)) return; 3097 3098 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3099 unsigned nparams = FTP->getNumArgs(); 3100 assert(FD->getNumParams() == nparams); 3101 3102 if (nparams > 3) { 3103 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3104 FD->setInvalidDecl(true); 3105 nparams = 3; 3106 } 3107 3108 // FIXME: a lot of the following diagnostics would be improved 3109 // if we had some location information about types. 3110 3111 QualType CharPP = 3112 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3113 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3114 3115 for (unsigned i = 0; i < nparams; ++i) { 3116 QualType AT = FTP->getArgType(i); 3117 3118 bool mismatch = true; 3119 3120 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3121 mismatch = false; 3122 else if (Expected[i] == CharPP) { 3123 // As an extension, the following forms are okay: 3124 // char const ** 3125 // char const * const * 3126 // char * const * 3127 3128 QualifierCollector qs; 3129 const PointerType* PT; 3130 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3131 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3132 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3133 qs.removeConst(); 3134 mismatch = !qs.empty(); 3135 } 3136 } 3137 3138 if (mismatch) { 3139 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3140 // TODO: suggest replacing given type with expected type 3141 FD->setInvalidDecl(true); 3142 } 3143 } 3144 3145 if (nparams == 1 && !FD->isInvalidDecl()) { 3146 Diag(FD->getLocation(), diag::warn_main_one_arg); 3147 } 3148} 3149 3150bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3151 // FIXME: Need strict checking. In C89, we need to check for 3152 // any assignment, increment, decrement, function-calls, or 3153 // commas outside of a sizeof. In C99, it's the same list, 3154 // except that the aforementioned are allowed in unevaluated 3155 // expressions. Everything else falls under the 3156 // "may accept other forms of constant expressions" exception. 3157 // (We never end up here for C++, so the constant expression 3158 // rules there don't matter.) 3159 if (Init->isConstantInitializer(Context)) 3160 return false; 3161 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3162 << Init->getSourceRange(); 3163 return true; 3164} 3165 3166void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3167 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3168} 3169 3170/// AddInitializerToDecl - Adds the initializer Init to the 3171/// declaration dcl. If DirectInit is true, this is C++ direct 3172/// initialization rather than copy initialization. 3173void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3174 Decl *RealDecl = dcl.getAs<Decl>(); 3175 // If there is no declaration, there was an error parsing it. Just ignore 3176 // the initializer. 3177 if (RealDecl == 0) 3178 return; 3179 3180 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3181 // With declarators parsed the way they are, the parser cannot 3182 // distinguish between a normal initializer and a pure-specifier. 3183 // Thus this grotesque test. 3184 IntegerLiteral *IL; 3185 Expr *Init = static_cast<Expr *>(init.get()); 3186 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3187 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3188 if (Method->isVirtualAsWritten()) { 3189 Method->setPure(); 3190 3191 // A class is abstract if at least one function is pure virtual. 3192 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3193 } else if (!Method->isInvalidDecl()) { 3194 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3195 << Method->getDeclName() << Init->getSourceRange(); 3196 Method->setInvalidDecl(); 3197 } 3198 } else { 3199 Diag(Method->getLocation(), diag::err_member_function_initialization) 3200 << Method->getDeclName() << Init->getSourceRange(); 3201 Method->setInvalidDecl(); 3202 } 3203 return; 3204 } 3205 3206 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3207 if (!VDecl) { 3208 if (getLangOptions().CPlusPlus && 3209 RealDecl->getLexicalDeclContext()->isRecord() && 3210 isa<NamedDecl>(RealDecl)) 3211 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3212 << cast<NamedDecl>(RealDecl)->getDeclName(); 3213 else 3214 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3215 RealDecl->setInvalidDecl(); 3216 return; 3217 } 3218 3219 if (!VDecl->getType()->isArrayType() && 3220 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3221 diag::err_typecheck_decl_incomplete_type)) { 3222 RealDecl->setInvalidDecl(); 3223 return; 3224 } 3225 3226 const VarDecl *Def = 0; 3227 if (VDecl->getDefinition(Def)) { 3228 Diag(VDecl->getLocation(), diag::err_redefinition) 3229 << VDecl->getDeclName(); 3230 Diag(Def->getLocation(), diag::note_previous_definition); 3231 VDecl->setInvalidDecl(); 3232 return; 3233 } 3234 3235 // Take ownership of the expression, now that we're sure we have somewhere 3236 // to put it. 3237 Expr *Init = init.takeAs<Expr>(); 3238 assert(Init && "missing initializer"); 3239 3240 // Get the decls type and save a reference for later, since 3241 // CheckInitializerTypes may change it. 3242 QualType DclT = VDecl->getType(), SavT = DclT; 3243 if (VDecl->isBlockVarDecl()) { 3244 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3245 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3246 VDecl->setInvalidDecl(); 3247 } else if (!VDecl->isInvalidDecl()) { 3248 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3249 VDecl->getDeclName(), DirectInit)) 3250 VDecl->setInvalidDecl(); 3251 3252 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3253 // Don't check invalid declarations to avoid emitting useless diagnostics. 3254 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3255 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3256 CheckForConstantInitializer(Init, DclT); 3257 } 3258 } 3259 } else if (VDecl->isStaticDataMember() && 3260 VDecl->getLexicalDeclContext()->isRecord()) { 3261 // This is an in-class initialization for a static data member, e.g., 3262 // 3263 // struct S { 3264 // static const int value = 17; 3265 // }; 3266 3267 // Attach the initializer 3268 VDecl->setInit(Context, Init); 3269 3270 // C++ [class.mem]p4: 3271 // A member-declarator can contain a constant-initializer only 3272 // if it declares a static member (9.4) of const integral or 3273 // const enumeration type, see 9.4.2. 3274 QualType T = VDecl->getType(); 3275 if (!T->isDependentType() && 3276 (!Context.getCanonicalType(T).isConstQualified() || 3277 !T->isIntegralType())) { 3278 Diag(VDecl->getLocation(), diag::err_member_initialization) 3279 << VDecl->getDeclName() << Init->getSourceRange(); 3280 VDecl->setInvalidDecl(); 3281 } else { 3282 // C++ [class.static.data]p4: 3283 // If a static data member is of const integral or const 3284 // enumeration type, its declaration in the class definition 3285 // can specify a constant-initializer which shall be an 3286 // integral constant expression (5.19). 3287 if (!Init->isTypeDependent() && 3288 !Init->getType()->isIntegralType()) { 3289 // We have a non-dependent, non-integral or enumeration type. 3290 Diag(Init->getSourceRange().getBegin(), 3291 diag::err_in_class_initializer_non_integral_type) 3292 << Init->getType() << Init->getSourceRange(); 3293 VDecl->setInvalidDecl(); 3294 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3295 // Check whether the expression is a constant expression. 3296 llvm::APSInt Value; 3297 SourceLocation Loc; 3298 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3299 Diag(Loc, diag::err_in_class_initializer_non_constant) 3300 << Init->getSourceRange(); 3301 VDecl->setInvalidDecl(); 3302 } else if (!VDecl->getType()->isDependentType()) 3303 ImpCastExprToType(Init, VDecl->getType()); 3304 } 3305 } 3306 } else if (VDecl->isFileVarDecl()) { 3307 if (VDecl->getStorageClass() == VarDecl::Extern) 3308 Diag(VDecl->getLocation(), diag::warn_extern_init); 3309 if (!VDecl->isInvalidDecl()) 3310 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3311 VDecl->getDeclName(), DirectInit)) 3312 VDecl->setInvalidDecl(); 3313 3314 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3315 // Don't check invalid declarations to avoid emitting useless diagnostics. 3316 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3317 // C99 6.7.8p4. All file scoped initializers need to be constant. 3318 CheckForConstantInitializer(Init, DclT); 3319 } 3320 } 3321 // If the type changed, it means we had an incomplete type that was 3322 // completed by the initializer. For example: 3323 // int ary[] = { 1, 3, 5 }; 3324 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3325 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3326 VDecl->setType(DclT); 3327 Init->setType(DclT); 3328 } 3329 3330 Init = MaybeCreateCXXExprWithTemporaries(Init, 3331 /*ShouldDestroyTemporaries=*/true); 3332 // Attach the initializer to the decl. 3333 VDecl->setInit(Context, Init); 3334 3335 // If the previous declaration of VDecl was a tentative definition, 3336 // remove it from the set of tentative definitions. 3337 if (VDecl->getPreviousDeclaration() && 3338 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3339 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3340 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3341 } 3342 3343 return; 3344} 3345 3346void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3347 bool TypeContainsUndeducedAuto) { 3348 Decl *RealDecl = dcl.getAs<Decl>(); 3349 3350 // If there is no declaration, there was an error parsing it. Just ignore it. 3351 if (RealDecl == 0) 3352 return; 3353 3354 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3355 QualType Type = Var->getType(); 3356 3357 // Record tentative definitions. 3358 if (Var->isTentativeDefinition(Context)) { 3359 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3360 InsertPair = 3361 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3362 3363 // Keep the latest definition in the map. If we see 'int i; int i;' we 3364 // want the second one in the map. 3365 InsertPair.first->second = Var; 3366 3367 // However, for the list, we don't care about the order, just make sure 3368 // that there are no dupes for a given declaration name. 3369 if (InsertPair.second) 3370 TentativeDefinitionList.push_back(Var->getDeclName()); 3371 } 3372 3373 // C++ [dcl.init.ref]p3: 3374 // The initializer can be omitted for a reference only in a 3375 // parameter declaration (8.3.5), in the declaration of a 3376 // function return type, in the declaration of a class member 3377 // within its class declaration (9.2), and where the extern 3378 // specifier is explicitly used. 3379 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3380 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3381 << Var->getDeclName() 3382 << SourceRange(Var->getLocation(), Var->getLocation()); 3383 Var->setInvalidDecl(); 3384 return; 3385 } 3386 3387 // C++0x [dcl.spec.auto]p3 3388 if (TypeContainsUndeducedAuto) { 3389 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3390 << Var->getDeclName() << Type; 3391 Var->setInvalidDecl(); 3392 return; 3393 } 3394 3395 // C++ [temp.expl.spec]p15: 3396 // An explicit specialization of a static data member of a template is a 3397 // definition if the declaration includes an initializer; otherwise, it 3398 // is a declaration. 3399 if (Var->isStaticDataMember() && 3400 Var->getInstantiatedFromStaticDataMember() && 3401 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3402 return; 3403 3404 // C++ [dcl.init]p9: 3405 // If no initializer is specified for an object, and the object 3406 // is of (possibly cv-qualified) non-POD class type (or array 3407 // thereof), the object shall be default-initialized; if the 3408 // object is of const-qualified type, the underlying class type 3409 // shall have a user-declared default constructor. 3410 // 3411 // FIXME: Diagnose the "user-declared default constructor" bit. 3412 if (getLangOptions().CPlusPlus) { 3413 QualType InitType = Type; 3414 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3415 InitType = Array->getElementType(); 3416 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3417 InitType->isRecordType() && !InitType->isDependentType()) { 3418 if (!RequireCompleteType(Var->getLocation(), InitType, 3419 diag::err_invalid_incomplete_type_use)) { 3420 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3421 3422 CXXConstructorDecl *Constructor 3423 = PerformInitializationByConstructor(InitType, 3424 MultiExprArg(*this, 0, 0), 3425 Var->getLocation(), 3426 SourceRange(Var->getLocation(), 3427 Var->getLocation()), 3428 Var->getDeclName(), 3429 IK_Default, 3430 ConstructorArgs); 3431 3432 // FIXME: Location info for the variable initialization? 3433 if (!Constructor) 3434 Var->setInvalidDecl(); 3435 else { 3436 // FIXME: Cope with initialization of arrays 3437 if (!Constructor->isTrivial() && 3438 InitializeVarWithConstructor(Var, Constructor, InitType, 3439 move_arg(ConstructorArgs))) 3440 Var->setInvalidDecl(); 3441 3442 FinalizeVarWithDestructor(Var, InitType); 3443 } 3444 } else { 3445 Var->setInvalidDecl(); 3446 } 3447 } 3448 } 3449 3450#if 0 3451 // FIXME: Temporarily disabled because we are not properly parsing 3452 // linkage specifications on declarations, e.g., 3453 // 3454 // extern "C" const CGPoint CGPointerZero; 3455 // 3456 // C++ [dcl.init]p9: 3457 // 3458 // If no initializer is specified for an object, and the 3459 // object is of (possibly cv-qualified) non-POD class type (or 3460 // array thereof), the object shall be default-initialized; if 3461 // the object is of const-qualified type, the underlying class 3462 // type shall have a user-declared default 3463 // constructor. Otherwise, if no initializer is specified for 3464 // an object, the object and its subobjects, if any, have an 3465 // indeterminate initial value; if the object or any of its 3466 // subobjects are of const-qualified type, the program is 3467 // ill-formed. 3468 // 3469 // This isn't technically an error in C, so we don't diagnose it. 3470 // 3471 // FIXME: Actually perform the POD/user-defined default 3472 // constructor check. 3473 if (getLangOptions().CPlusPlus && 3474 Context.getCanonicalType(Type).isConstQualified() && 3475 !Var->hasExternalStorage()) 3476 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3477 << Var->getName() 3478 << SourceRange(Var->getLocation(), Var->getLocation()); 3479#endif 3480 } 3481} 3482 3483Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3484 DeclPtrTy *Group, 3485 unsigned NumDecls) { 3486 llvm::SmallVector<Decl*, 8> Decls; 3487 3488 if (DS.isTypeSpecOwned()) 3489 Decls.push_back((Decl*)DS.getTypeRep()); 3490 3491 for (unsigned i = 0; i != NumDecls; ++i) 3492 if (Decl *D = Group[i].getAs<Decl>()) 3493 Decls.push_back(D); 3494 3495 // Perform semantic analysis that depends on having fully processed both 3496 // the declarator and initializer. 3497 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3498 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3499 if (!IDecl) 3500 continue; 3501 QualType T = IDecl->getType(); 3502 3503 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3504 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3505 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3506 if (!IDecl->isInvalidDecl() && 3507 RequireCompleteType(IDecl->getLocation(), T, 3508 diag::err_typecheck_decl_incomplete_type)) 3509 IDecl->setInvalidDecl(); 3510 } 3511 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3512 // object that has file scope without an initializer, and without a 3513 // storage-class specifier or with the storage-class specifier "static", 3514 // constitutes a tentative definition. Note: A tentative definition with 3515 // external linkage is valid (C99 6.2.2p5). 3516 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3517 if (const IncompleteArrayType *ArrayT 3518 = Context.getAsIncompleteArrayType(T)) { 3519 if (RequireCompleteType(IDecl->getLocation(), 3520 ArrayT->getElementType(), 3521 diag::err_illegal_decl_array_incomplete_type)) 3522 IDecl->setInvalidDecl(); 3523 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3524 // C99 6.9.2p3: If the declaration of an identifier for an object is 3525 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3526 // declared type shall not be an incomplete type. 3527 // NOTE: code such as the following 3528 // static struct s; 3529 // struct s { int a; }; 3530 // is accepted by gcc. Hence here we issue a warning instead of 3531 // an error and we do not invalidate the static declaration. 3532 // NOTE: to avoid multiple warnings, only check the first declaration. 3533 if (IDecl->getPreviousDeclaration() == 0) 3534 RequireCompleteType(IDecl->getLocation(), T, 3535 diag::ext_typecheck_decl_incomplete_type); 3536 } 3537 } 3538 } 3539 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3540 Decls.data(), Decls.size())); 3541} 3542 3543 3544/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3545/// to introduce parameters into function prototype scope. 3546Sema::DeclPtrTy 3547Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3548 const DeclSpec &DS = D.getDeclSpec(); 3549 3550 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3551 VarDecl::StorageClass StorageClass = VarDecl::None; 3552 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3553 StorageClass = VarDecl::Register; 3554 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3555 Diag(DS.getStorageClassSpecLoc(), 3556 diag::err_invalid_storage_class_in_func_decl); 3557 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3558 } 3559 3560 if (D.getDeclSpec().isThreadSpecified()) 3561 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3562 3563 DiagnoseFunctionSpecifiers(D); 3564 3565 // Check that there are no default arguments inside the type of this 3566 // parameter (C++ only). 3567 if (getLangOptions().CPlusPlus) 3568 CheckExtraCXXDefaultArguments(D); 3569 3570 DeclaratorInfo *DInfo = 0; 3571 TagDecl *OwnedDecl = 0; 3572 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3573 &OwnedDecl); 3574 3575 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3576 // C++ [dcl.fct]p6: 3577 // Types shall not be defined in return or parameter types. 3578 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3579 << Context.getTypeDeclType(OwnedDecl); 3580 } 3581 3582 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3583 // Can this happen for params? We already checked that they don't conflict 3584 // among each other. Here they can only shadow globals, which is ok. 3585 IdentifierInfo *II = D.getIdentifier(); 3586 if (II) { 3587 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3588 if (PrevDecl->isTemplateParameter()) { 3589 // Maybe we will complain about the shadowed template parameter. 3590 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3591 // Just pretend that we didn't see the previous declaration. 3592 PrevDecl = 0; 3593 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3594 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3595 3596 // Recover by removing the name 3597 II = 0; 3598 D.SetIdentifier(0, D.getIdentifierLoc()); 3599 } 3600 } 3601 } 3602 3603 // Parameters can not be abstract class types. 3604 // For record types, this is done by the AbstractClassUsageDiagnoser once 3605 // the class has been completely parsed. 3606 if (!CurContext->isRecord() && 3607 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3608 diag::err_abstract_type_in_decl, 3609 AbstractParamType)) 3610 D.setInvalidType(true); 3611 3612 QualType T = adjustParameterType(parmDeclType); 3613 3614 ParmVarDecl *New; 3615 if (T == parmDeclType) // parameter type did not need adjustment 3616 New = ParmVarDecl::Create(Context, CurContext, 3617 D.getIdentifierLoc(), II, 3618 parmDeclType, DInfo, StorageClass, 3619 0); 3620 else // keep track of both the adjusted and unadjusted types 3621 New = OriginalParmVarDecl::Create(Context, CurContext, 3622 D.getIdentifierLoc(), II, T, DInfo, 3623 parmDeclType, StorageClass, 0); 3624 3625 if (D.isInvalidType()) 3626 New->setInvalidDecl(); 3627 3628 // Parameter declarators cannot be interface types. All ObjC objects are 3629 // passed by reference. 3630 if (T->isObjCInterfaceType()) { 3631 Diag(D.getIdentifierLoc(), 3632 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3633 New->setInvalidDecl(); 3634 } 3635 3636 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3637 if (D.getCXXScopeSpec().isSet()) { 3638 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3639 << D.getCXXScopeSpec().getRange(); 3640 New->setInvalidDecl(); 3641 } 3642 3643 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3644 // duration shall not be qualified by an address-space qualifier." 3645 // Since all parameters have automatic store duration, they can not have 3646 // an address space. 3647 if (T.getAddressSpace() != 0) { 3648 Diag(D.getIdentifierLoc(), 3649 diag::err_arg_with_address_space); 3650 New->setInvalidDecl(); 3651 } 3652 3653 3654 // Add the parameter declaration into this scope. 3655 S->AddDecl(DeclPtrTy::make(New)); 3656 if (II) 3657 IdResolver.AddDecl(New); 3658 3659 ProcessDeclAttributes(S, New, D); 3660 3661 if (New->hasAttr<BlocksAttr>()) { 3662 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3663 } 3664 return DeclPtrTy::make(New); 3665} 3666 3667void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3668 SourceLocation LocAfterDecls) { 3669 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3670 "Not a function declarator!"); 3671 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3672 3673 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3674 // for a K&R function. 3675 if (!FTI.hasPrototype) { 3676 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3677 --i; 3678 if (FTI.ArgInfo[i].Param == 0) { 3679 std::string Code = " int "; 3680 Code += FTI.ArgInfo[i].Ident->getName(); 3681 Code += ";\n"; 3682 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3683 << FTI.ArgInfo[i].Ident 3684 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3685 3686 // Implicitly declare the argument as type 'int' for lack of a better 3687 // type. 3688 DeclSpec DS; 3689 const char* PrevSpec; // unused 3690 unsigned DiagID; // unused 3691 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3692 PrevSpec, DiagID); 3693 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3694 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3695 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3696 } 3697 } 3698 } 3699} 3700 3701Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3702 Declarator &D) { 3703 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3704 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3705 "Not a function declarator!"); 3706 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3707 3708 if (FTI.hasPrototype) { 3709 // FIXME: Diagnose arguments without names in C. 3710 } 3711 3712 Scope *ParentScope = FnBodyScope->getParent(); 3713 3714 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3715 MultiTemplateParamsArg(*this), 3716 /*IsFunctionDefinition=*/true); 3717 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3718} 3719 3720Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3721 if (!D) 3722 return D; 3723 FunctionDecl *FD = 0; 3724 3725 if (FunctionTemplateDecl *FunTmpl 3726 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3727 FD = FunTmpl->getTemplatedDecl(); 3728 else 3729 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3730 3731 CurFunctionNeedsScopeChecking = false; 3732 3733 // See if this is a redefinition. 3734 const FunctionDecl *Definition; 3735 if (FD->getBody(Definition)) { 3736 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3737 Diag(Definition->getLocation(), diag::note_previous_definition); 3738 } 3739 3740 // Builtin functions cannot be defined. 3741 if (unsigned BuiltinID = FD->getBuiltinID()) { 3742 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3743 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3744 FD->setInvalidDecl(); 3745 } 3746 } 3747 3748 // The return type of a function definition must be complete 3749 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3750 QualType ResultType = FD->getResultType(); 3751 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3752 !FD->isInvalidDecl() && 3753 RequireCompleteType(FD->getLocation(), ResultType, 3754 diag::err_func_def_incomplete_result)) 3755 FD->setInvalidDecl(); 3756 3757 // GNU warning -Wmissing-prototypes: 3758 // Warn if a global function is defined without a previous 3759 // prototype declaration. This warning is issued even if the 3760 // definition itself provides a prototype. The aim is to detect 3761 // global functions that fail to be declared in header files. 3762 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3763 !FD->isMain()) { 3764 bool MissingPrototype = true; 3765 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3766 Prev; Prev = Prev->getPreviousDeclaration()) { 3767 // Ignore any declarations that occur in function or method 3768 // scope, because they aren't visible from the header. 3769 if (Prev->getDeclContext()->isFunctionOrMethod()) 3770 continue; 3771 3772 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3773 break; 3774 } 3775 3776 if (MissingPrototype) 3777 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3778 } 3779 3780 if (FnBodyScope) 3781 PushDeclContext(FnBodyScope, FD); 3782 3783 // Check the validity of our function parameters 3784 CheckParmsForFunctionDef(FD); 3785 3786 // Introduce our parameters into the function scope 3787 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3788 ParmVarDecl *Param = FD->getParamDecl(p); 3789 Param->setOwningFunction(FD); 3790 3791 // If this has an identifier, add it to the scope stack. 3792 if (Param->getIdentifier() && FnBodyScope) 3793 PushOnScopeChains(Param, FnBodyScope); 3794 } 3795 3796 // Checking attributes of current function definition 3797 // dllimport attribute. 3798 if (FD->getAttr<DLLImportAttr>() && 3799 (!FD->getAttr<DLLExportAttr>())) { 3800 // dllimport attribute cannot be applied to definition. 3801 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3802 Diag(FD->getLocation(), 3803 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3804 << "dllimport"; 3805 FD->setInvalidDecl(); 3806 return DeclPtrTy::make(FD); 3807 } else { 3808 // If a symbol previously declared dllimport is later defined, the 3809 // attribute is ignored in subsequent references, and a warning is 3810 // emitted. 3811 Diag(FD->getLocation(), 3812 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3813 << FD->getNameAsCString() << "dllimport"; 3814 } 3815 } 3816 return DeclPtrTy::make(FD); 3817} 3818 3819Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3820 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3821} 3822 3823Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3824 bool IsInstantiation) { 3825 Decl *dcl = D.getAs<Decl>(); 3826 Stmt *Body = BodyArg.takeAs<Stmt>(); 3827 3828 FunctionDecl *FD = 0; 3829 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3830 if (FunTmpl) 3831 FD = FunTmpl->getTemplatedDecl(); 3832 else 3833 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3834 3835 if (FD) { 3836 FD->setBody(Body); 3837 if (FD->isMain()) 3838 // C and C++ allow for main to automagically return 0. 3839 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3840 FD->setHasImplicitReturnZero(true); 3841 else 3842 CheckFallThroughForFunctionDef(FD, Body); 3843 3844 if (!FD->isInvalidDecl()) 3845 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3846 3847 // C++ [basic.def.odr]p2: 3848 // [...] A virtual member function is used if it is not pure. [...] 3849 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3850 if (Method->isVirtual() && !Method->isPure()) 3851 MarkDeclarationReferenced(Method->getLocation(), Method); 3852 3853 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3854 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3855 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3856 MD->setBody(Body); 3857 CheckFallThroughForFunctionDef(MD, Body); 3858 MD->setEndLoc(Body->getLocEnd()); 3859 3860 if (!MD->isInvalidDecl()) 3861 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3862 } else { 3863 Body->Destroy(Context); 3864 return DeclPtrTy(); 3865 } 3866 if (!IsInstantiation) 3867 PopDeclContext(); 3868 3869 // Verify and clean out per-function state. 3870 3871 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3872 3873 // Check goto/label use. 3874 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3875 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3876 LabelStmt *L = I->second; 3877 3878 // Verify that we have no forward references left. If so, there was a goto 3879 // or address of a label taken, but no definition of it. Label fwd 3880 // definitions are indicated with a null substmt. 3881 if (L->getSubStmt() != 0) 3882 continue; 3883 3884 // Emit error. 3885 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3886 3887 // At this point, we have gotos that use the bogus label. Stitch it into 3888 // the function body so that they aren't leaked and that the AST is well 3889 // formed. 3890 if (Body == 0) { 3891 // The whole function wasn't parsed correctly, just delete this. 3892 L->Destroy(Context); 3893 continue; 3894 } 3895 3896 // Otherwise, the body is valid: we want to stitch the label decl into the 3897 // function somewhere so that it is properly owned and so that the goto 3898 // has a valid target. Do this by creating a new compound stmt with the 3899 // label in it. 3900 3901 // Give the label a sub-statement. 3902 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3903 3904 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3905 cast<CXXTryStmt>(Body)->getTryBlock() : 3906 cast<CompoundStmt>(Body); 3907 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3908 Elements.push_back(L); 3909 Compound->setStmts(Context, &Elements[0], Elements.size()); 3910 } 3911 FunctionLabelMap.clear(); 3912 3913 if (!Body) return D; 3914 3915 // Verify that that gotos and switch cases don't jump into scopes illegally. 3916 if (CurFunctionNeedsScopeChecking) 3917 DiagnoseInvalidJumps(Body); 3918 3919 // C++ constructors that have function-try-blocks can't have return 3920 // statements in the handlers of that block. (C++ [except.handle]p14) 3921 // Verify this. 3922 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3923 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3924 3925 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3926 computeBaseOrMembersToDestroy(Destructor); 3927 return D; 3928} 3929 3930/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3931/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3932NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3933 IdentifierInfo &II, Scope *S) { 3934 // Before we produce a declaration for an implicitly defined 3935 // function, see whether there was a locally-scoped declaration of 3936 // this name as a function or variable. If so, use that 3937 // (non-visible) declaration, and complain about it. 3938 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3939 = LocallyScopedExternalDecls.find(&II); 3940 if (Pos != LocallyScopedExternalDecls.end()) { 3941 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3942 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3943 return Pos->second; 3944 } 3945 3946 // Extension in C99. Legal in C90, but warn about it. 3947 static const unsigned int BuiltinLen = strlen("__builtin_"); 3948 if (II.getLength() > BuiltinLen && 3949 std::equal(II.getName(), II.getName() + BuiltinLen, "__builtin_")) 3950 Diag(Loc, diag::warn_builtin_unknown) << &II; 3951 else if (getLangOptions().C99) 3952 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3953 else 3954 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3955 3956 // Set a Declarator for the implicit definition: int foo(); 3957 const char *Dummy; 3958 DeclSpec DS; 3959 unsigned DiagID; 3960 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3961 Error = Error; // Silence warning. 3962 assert(!Error && "Error setting up implicit decl!"); 3963 Declarator D(DS, Declarator::BlockContext); 3964 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3965 0, 0, false, SourceLocation(), 3966 false, 0,0,0, Loc, Loc, D), 3967 SourceLocation()); 3968 D.SetIdentifier(&II, Loc); 3969 3970 // Insert this function into translation-unit scope. 3971 3972 DeclContext *PrevDC = CurContext; 3973 CurContext = Context.getTranslationUnitDecl(); 3974 3975 FunctionDecl *FD = 3976 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3977 FD->setImplicit(); 3978 3979 CurContext = PrevDC; 3980 3981 AddKnownFunctionAttributes(FD); 3982 3983 return FD; 3984} 3985 3986/// \brief Adds any function attributes that we know a priori based on 3987/// the declaration of this function. 3988/// 3989/// These attributes can apply both to implicitly-declared builtins 3990/// (like __builtin___printf_chk) or to library-declared functions 3991/// like NSLog or printf. 3992void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3993 if (FD->isInvalidDecl()) 3994 return; 3995 3996 // If this is a built-in function, map its builtin attributes to 3997 // actual attributes. 3998 if (unsigned BuiltinID = FD->getBuiltinID()) { 3999 // Handle printf-formatting attributes. 4000 unsigned FormatIdx; 4001 bool HasVAListArg; 4002 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4003 if (!FD->getAttr<FormatAttr>()) 4004 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4005 HasVAListArg ? 0 : FormatIdx + 2)); 4006 } 4007 4008 // Mark const if we don't care about errno and that is the only 4009 // thing preventing the function from being const. This allows 4010 // IRgen to use LLVM intrinsics for such functions. 4011 if (!getLangOptions().MathErrno && 4012 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4013 if (!FD->getAttr<ConstAttr>()) 4014 FD->addAttr(::new (Context) ConstAttr()); 4015 } 4016 4017 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4018 FD->addAttr(::new (Context) NoReturnAttr()); 4019 } 4020 4021 IdentifierInfo *Name = FD->getIdentifier(); 4022 if (!Name) 4023 return; 4024 if ((!getLangOptions().CPlusPlus && 4025 FD->getDeclContext()->isTranslationUnit()) || 4026 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4027 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4028 LinkageSpecDecl::lang_c)) { 4029 // Okay: this could be a libc/libm/Objective-C function we know 4030 // about. 4031 } else 4032 return; 4033 4034 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4035 // FIXME: NSLog and NSLogv should be target specific 4036 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4037 // FIXME: We known better than our headers. 4038 const_cast<FormatAttr *>(Format)->setType("printf"); 4039 } else 4040 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4041 Name->isStr("NSLogv") ? 0 : 2)); 4042 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4043 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4044 // target-specific builtins, perhaps? 4045 if (!FD->getAttr<FormatAttr>()) 4046 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4047 Name->isStr("vasprintf") ? 0 : 3)); 4048 } 4049} 4050 4051TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 4052 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4053 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4054 4055 // Scope manipulation handled by caller. 4056 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4057 D.getIdentifierLoc(), 4058 D.getIdentifier(), 4059 T); 4060 4061 if (const TagType *TT = T->getAs<TagType>()) { 4062 TagDecl *TD = TT->getDecl(); 4063 4064 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4065 // keep track of the TypedefDecl. 4066 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4067 TD->setTypedefForAnonDecl(NewTD); 4068 } 4069 4070 if (D.isInvalidType()) 4071 NewTD->setInvalidDecl(); 4072 return NewTD; 4073} 4074 4075 4076/// \brief Determine whether a tag with a given kind is acceptable 4077/// as a redeclaration of the given tag declaration. 4078/// 4079/// \returns true if the new tag kind is acceptable, false otherwise. 4080bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4081 TagDecl::TagKind NewTag, 4082 SourceLocation NewTagLoc, 4083 const IdentifierInfo &Name) { 4084 // C++ [dcl.type.elab]p3: 4085 // The class-key or enum keyword present in the 4086 // elaborated-type-specifier shall agree in kind with the 4087 // declaration to which the name in theelaborated-type-specifier 4088 // refers. This rule also applies to the form of 4089 // elaborated-type-specifier that declares a class-name or 4090 // friend class since it can be construed as referring to the 4091 // definition of the class. Thus, in any 4092 // elaborated-type-specifier, the enum keyword shall be used to 4093 // refer to an enumeration (7.2), the union class-keyshall be 4094 // used to refer to a union (clause 9), and either the class or 4095 // struct class-key shall be used to refer to a class (clause 9) 4096 // declared using the class or struct class-key. 4097 TagDecl::TagKind OldTag = Previous->getTagKind(); 4098 if (OldTag == NewTag) 4099 return true; 4100 4101 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4102 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4103 // Warn about the struct/class tag mismatch. 4104 bool isTemplate = false; 4105 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4106 isTemplate = Record->getDescribedClassTemplate(); 4107 4108 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4109 << (NewTag == TagDecl::TK_class) 4110 << isTemplate << &Name 4111 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4112 OldTag == TagDecl::TK_class? "class" : "struct"); 4113 Diag(Previous->getLocation(), diag::note_previous_use); 4114 return true; 4115 } 4116 return false; 4117} 4118 4119/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4120/// former case, Name will be non-null. In the later case, Name will be null. 4121/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4122/// reference/declaration/definition of a tag. 4123Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4124 SourceLocation KWLoc, const CXXScopeSpec &SS, 4125 IdentifierInfo *Name, SourceLocation NameLoc, 4126 AttributeList *Attr, AccessSpecifier AS, 4127 MultiTemplateParamsArg TemplateParameterLists, 4128 bool &OwnedDecl, bool &IsDependent) { 4129 // If this is not a definition, it must have a name. 4130 assert((Name != 0 || TUK == TUK_Definition) && 4131 "Nameless record must be a definition!"); 4132 4133 OwnedDecl = false; 4134 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4135 4136 // FIXME: Check explicit specializations more carefully. 4137 bool isExplicitSpecialization = false; 4138 if (TUK != TUK_Reference) { 4139 if (TemplateParameterList *TemplateParams 4140 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4141 (TemplateParameterList**)TemplateParameterLists.get(), 4142 TemplateParameterLists.size(), 4143 isExplicitSpecialization)) { 4144 if (TemplateParams->size() > 0) { 4145 // This is a declaration or definition of a class template (which may 4146 // be a member of another template). 4147 OwnedDecl = false; 4148 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4149 SS, Name, NameLoc, Attr, 4150 TemplateParams, 4151 AS); 4152 TemplateParameterLists.release(); 4153 return Result.get(); 4154 } else { 4155 // The "template<>" header is extraneous. 4156 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4157 << ElaboratedType::getNameForTagKind(Kind) << Name; 4158 isExplicitSpecialization = true; 4159 } 4160 } 4161 4162 TemplateParameterLists.release(); 4163 } 4164 4165 DeclContext *SearchDC = CurContext; 4166 DeclContext *DC = CurContext; 4167 NamedDecl *PrevDecl = 0; 4168 bool isStdBadAlloc = false; 4169 bool Invalid = false; 4170 4171 bool RedeclarationOnly = (TUK != TUK_Reference); 4172 4173 if (Name && SS.isNotEmpty()) { 4174 // We have a nested-name tag ('struct foo::bar'). 4175 4176 // Check for invalid 'foo::'. 4177 if (SS.isInvalid()) { 4178 Name = 0; 4179 goto CreateNewDecl; 4180 } 4181 4182 // If this is a friend or a reference to a class in a dependent 4183 // context, don't try to make a decl for it. 4184 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4185 DC = computeDeclContext(SS, false); 4186 if (!DC) { 4187 IsDependent = true; 4188 return DeclPtrTy(); 4189 } 4190 } 4191 4192 if (RequireCompleteDeclContext(SS)) 4193 return DeclPtrTy::make((Decl *)0); 4194 4195 DC = computeDeclContext(SS, true); 4196 SearchDC = DC; 4197 // Look-up name inside 'foo::'. 4198 LookupResult R; 4199 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4200 4201 if (R.isAmbiguous()) { 4202 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4203 return DeclPtrTy(); 4204 } 4205 4206 if (R.getKind() == LookupResult::Found) 4207 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4208 4209 // A tag 'foo::bar' must already exist. 4210 if (!PrevDecl) { 4211 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4212 Name = 0; 4213 Invalid = true; 4214 goto CreateNewDecl; 4215 } 4216 } else if (Name) { 4217 // If this is a named struct, check to see if there was a previous forward 4218 // declaration or definition. 4219 // FIXME: We're looking into outer scopes here, even when we 4220 // shouldn't be. Doing so can result in ambiguities that we 4221 // shouldn't be diagnosing. 4222 LookupResult R; 4223 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4224 if (R.isAmbiguous()) { 4225 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4226 // FIXME: This is not best way to recover from case like: 4227 // 4228 // struct S s; 4229 // 4230 // causes needless "incomplete type" error later. 4231 Name = 0; 4232 PrevDecl = 0; 4233 Invalid = true; 4234 } else 4235 PrevDecl = R.getAsSingleDecl(Context); 4236 4237 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4238 // FIXME: This makes sure that we ignore the contexts associated 4239 // with C structs, unions, and enums when looking for a matching 4240 // tag declaration or definition. See the similar lookup tweak 4241 // in Sema::LookupName; is there a better way to deal with this? 4242 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4243 SearchDC = SearchDC->getParent(); 4244 } 4245 } 4246 4247 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4248 // Maybe we will complain about the shadowed template parameter. 4249 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4250 // Just pretend that we didn't see the previous declaration. 4251 PrevDecl = 0; 4252 } 4253 4254 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4255 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4256 // This is a declaration of or a reference to "std::bad_alloc". 4257 isStdBadAlloc = true; 4258 4259 if (!PrevDecl && StdBadAlloc) { 4260 // std::bad_alloc has been implicitly declared (but made invisible to 4261 // name lookup). Fill in this implicit declaration as the previous 4262 // declaration, so that the declarations get chained appropriately. 4263 PrevDecl = StdBadAlloc; 4264 } 4265 } 4266 4267 if (PrevDecl) { 4268 // Check whether the previous declaration is usable. 4269 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4270 4271 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4272 // If this is a use of a previous tag, or if the tag is already declared 4273 // in the same scope (so that the definition/declaration completes or 4274 // rementions the tag), reuse the decl. 4275 if (TUK == TUK_Reference || TUK == TUK_Friend || 4276 isDeclInScope(PrevDecl, SearchDC, S)) { 4277 // Make sure that this wasn't declared as an enum and now used as a 4278 // struct or something similar. 4279 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4280 bool SafeToContinue 4281 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4282 Kind != TagDecl::TK_enum); 4283 if (SafeToContinue) 4284 Diag(KWLoc, diag::err_use_with_wrong_tag) 4285 << Name 4286 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4287 PrevTagDecl->getKindName()); 4288 else 4289 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4290 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4291 4292 if (SafeToContinue) 4293 Kind = PrevTagDecl->getTagKind(); 4294 else { 4295 // Recover by making this an anonymous redefinition. 4296 Name = 0; 4297 PrevDecl = 0; 4298 Invalid = true; 4299 } 4300 } 4301 4302 if (!Invalid) { 4303 // If this is a use, just return the declaration we found. 4304 4305 // FIXME: In the future, return a variant or some other clue 4306 // for the consumer of this Decl to know it doesn't own it. 4307 // For our current ASTs this shouldn't be a problem, but will 4308 // need to be changed with DeclGroups. 4309 if (TUK == TUK_Reference || TUK == TUK_Friend) 4310 return DeclPtrTy::make(PrevDecl); 4311 4312 // Diagnose attempts to redefine a tag. 4313 if (TUK == TUK_Definition) { 4314 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4315 // If we're defining a specialization and the previous definition 4316 // is from an implicit instantiation, don't emit an error 4317 // here; we'll catch this in the general case below. 4318 if (!isExplicitSpecialization || 4319 !isa<CXXRecordDecl>(Def) || 4320 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4321 == TSK_ExplicitSpecialization) { 4322 Diag(NameLoc, diag::err_redefinition) << Name; 4323 Diag(Def->getLocation(), diag::note_previous_definition); 4324 // If this is a redefinition, recover by making this 4325 // struct be anonymous, which will make any later 4326 // references get the previous definition. 4327 Name = 0; 4328 PrevDecl = 0; 4329 Invalid = true; 4330 } 4331 } else { 4332 // If the type is currently being defined, complain 4333 // about a nested redefinition. 4334 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4335 if (Tag->isBeingDefined()) { 4336 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4337 Diag(PrevTagDecl->getLocation(), 4338 diag::note_previous_definition); 4339 Name = 0; 4340 PrevDecl = 0; 4341 Invalid = true; 4342 } 4343 } 4344 4345 // Okay, this is definition of a previously declared or referenced 4346 // tag PrevDecl. We're going to create a new Decl for it. 4347 } 4348 } 4349 // If we get here we have (another) forward declaration or we 4350 // have a definition. Just create a new decl. 4351 4352 } else { 4353 // If we get here, this is a definition of a new tag type in a nested 4354 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4355 // new decl/type. We set PrevDecl to NULL so that the entities 4356 // have distinct types. 4357 PrevDecl = 0; 4358 } 4359 // If we get here, we're going to create a new Decl. If PrevDecl 4360 // is non-NULL, it's a definition of the tag declared by 4361 // PrevDecl. If it's NULL, we have a new definition. 4362 } else { 4363 // PrevDecl is a namespace, template, or anything else 4364 // that lives in the IDNS_Tag identifier namespace. 4365 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4366 // The tag name clashes with a namespace name, issue an error and 4367 // recover by making this tag be anonymous. 4368 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4369 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4370 Name = 0; 4371 PrevDecl = 0; 4372 Invalid = true; 4373 } else { 4374 // The existing declaration isn't relevant to us; we're in a 4375 // new scope, so clear out the previous declaration. 4376 PrevDecl = 0; 4377 } 4378 } 4379 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4380 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4381 // C++ [basic.scope.pdecl]p5: 4382 // -- for an elaborated-type-specifier of the form 4383 // 4384 // class-key identifier 4385 // 4386 // if the elaborated-type-specifier is used in the 4387 // decl-specifier-seq or parameter-declaration-clause of a 4388 // function defined in namespace scope, the identifier is 4389 // declared as a class-name in the namespace that contains 4390 // the declaration; otherwise, except as a friend 4391 // declaration, the identifier is declared in the smallest 4392 // non-class, non-function-prototype scope that contains the 4393 // declaration. 4394 // 4395 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4396 // C structs and unions. 4397 // 4398 // GNU C also supports this behavior as part of its incomplete 4399 // enum types extension, while GNU C++ does not. 4400 // 4401 // Find the context where we'll be declaring the tag. 4402 // FIXME: We would like to maintain the current DeclContext as the 4403 // lexical context, 4404 while (SearchDC->isRecord()) 4405 SearchDC = SearchDC->getParent(); 4406 4407 // Find the scope where we'll be declaring the tag. 4408 while (S->isClassScope() || 4409 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4410 ((S->getFlags() & Scope::DeclScope) == 0) || 4411 (S->getEntity() && 4412 ((DeclContext *)S->getEntity())->isTransparentContext())) 4413 S = S->getParent(); 4414 4415 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4416 // C++ [namespace.memdef]p3: 4417 // If a friend declaration in a non-local class first declares a 4418 // class or function, the friend class or function is a member of 4419 // the innermost enclosing namespace. 4420 while (!SearchDC->isFileContext()) 4421 SearchDC = SearchDC->getParent(); 4422 4423 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4424 while (S->getEntity() != SearchDC) 4425 S = S->getParent(); 4426 } 4427 4428CreateNewDecl: 4429 4430 // If there is an identifier, use the location of the identifier as the 4431 // location of the decl, otherwise use the location of the struct/union 4432 // keyword. 4433 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4434 4435 // Otherwise, create a new declaration. If there is a previous 4436 // declaration of the same entity, the two will be linked via 4437 // PrevDecl. 4438 TagDecl *New; 4439 4440 if (Kind == TagDecl::TK_enum) { 4441 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4442 // enum X { A, B, C } D; D should chain to X. 4443 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4444 cast_or_null<EnumDecl>(PrevDecl)); 4445 // If this is an undefined enum, warn. 4446 if (TUK != TUK_Definition && !Invalid) { 4447 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4448 : diag::ext_forward_ref_enum; 4449 Diag(Loc, DK); 4450 } 4451 } else { 4452 // struct/union/class 4453 4454 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4455 // struct X { int A; } D; D should chain to X. 4456 if (getLangOptions().CPlusPlus) { 4457 // FIXME: Look for a way to use RecordDecl for simple structs. 4458 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4459 cast_or_null<CXXRecordDecl>(PrevDecl)); 4460 4461 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4462 StdBadAlloc = cast<CXXRecordDecl>(New); 4463 } else 4464 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4465 cast_or_null<RecordDecl>(PrevDecl)); 4466 } 4467 4468 if (Kind != TagDecl::TK_enum) { 4469 // Handle #pragma pack: if the #pragma pack stack has non-default 4470 // alignment, make up a packed attribute for this decl. These 4471 // attributes are checked when the ASTContext lays out the 4472 // structure. 4473 // 4474 // It is important for implementing the correct semantics that this 4475 // happen here (in act on tag decl). The #pragma pack stack is 4476 // maintained as a result of parser callbacks which can occur at 4477 // many points during the parsing of a struct declaration (because 4478 // the #pragma tokens are effectively skipped over during the 4479 // parsing of the struct). 4480 if (unsigned Alignment = getPragmaPackAlignment()) 4481 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4482 } 4483 4484 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4485 // C++ [dcl.typedef]p3: 4486 // [...] Similarly, in a given scope, a class or enumeration 4487 // shall not be declared with the same name as a typedef-name 4488 // that is declared in that scope and refers to a type other 4489 // than the class or enumeration itself. 4490 LookupResult Lookup; 4491 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4492 TypedefDecl *PrevTypedef = 0; 4493 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4494 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4495 4496 NamedDecl *PrevTypedefNamed = PrevTypedef; 4497 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4498 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4499 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4500 Diag(Loc, diag::err_tag_definition_of_typedef) 4501 << Context.getTypeDeclType(New) 4502 << PrevTypedef->getUnderlyingType(); 4503 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4504 Invalid = true; 4505 } 4506 } 4507 4508 // If this is a specialization of a member class (of a class template), 4509 // check the specialization. 4510 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4511 Invalid = true; 4512 4513 if (Invalid) 4514 New->setInvalidDecl(); 4515 4516 if (Attr) 4517 ProcessDeclAttributeList(S, New, Attr); 4518 4519 // If we're declaring or defining a tag in function prototype scope 4520 // in C, note that this type can only be used within the function. 4521 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4522 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4523 4524 // Set the lexical context. If the tag has a C++ scope specifier, the 4525 // lexical context will be different from the semantic context. 4526 New->setLexicalDeclContext(CurContext); 4527 4528 // Mark this as a friend decl if applicable. 4529 if (TUK == TUK_Friend) 4530 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4531 4532 // Set the access specifier. 4533 if (!Invalid && TUK != TUK_Friend) 4534 SetMemberAccessSpecifier(New, PrevDecl, AS); 4535 4536 if (TUK == TUK_Definition) 4537 New->startDefinition(); 4538 4539 // If this has an identifier, add it to the scope stack. 4540 if (TUK == TUK_Friend) { 4541 // We might be replacing an existing declaration in the lookup tables; 4542 // if so, borrow its access specifier. 4543 if (PrevDecl) 4544 New->setAccess(PrevDecl->getAccess()); 4545 4546 // Friend tag decls are visible in fairly strange ways. 4547 if (!CurContext->isDependentContext()) { 4548 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4549 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4550 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4551 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4552 } 4553 } else if (Name) { 4554 S = getNonFieldDeclScope(S); 4555 PushOnScopeChains(New, S); 4556 } else { 4557 CurContext->addDecl(New); 4558 } 4559 4560 // If this is the C FILE type, notify the AST context. 4561 if (IdentifierInfo *II = New->getIdentifier()) 4562 if (!New->isInvalidDecl() && 4563 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4564 II->isStr("FILE")) 4565 Context.setFILEDecl(New); 4566 4567 OwnedDecl = true; 4568 return DeclPtrTy::make(New); 4569} 4570 4571void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4572 AdjustDeclIfTemplate(TagD); 4573 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4574 4575 // Enter the tag context. 4576 PushDeclContext(S, Tag); 4577 4578 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4579 FieldCollector->StartClass(); 4580 4581 if (Record->getIdentifier()) { 4582 // C++ [class]p2: 4583 // [...] The class-name is also inserted into the scope of the 4584 // class itself; this is known as the injected-class-name. For 4585 // purposes of access checking, the injected-class-name is treated 4586 // as if it were a public member name. 4587 CXXRecordDecl *InjectedClassName 4588 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4589 CurContext, Record->getLocation(), 4590 Record->getIdentifier(), 4591 Record->getTagKeywordLoc(), 4592 Record); 4593 InjectedClassName->setImplicit(); 4594 InjectedClassName->setAccess(AS_public); 4595 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4596 InjectedClassName->setDescribedClassTemplate(Template); 4597 PushOnScopeChains(InjectedClassName, S); 4598 assert(InjectedClassName->isInjectedClassName() && 4599 "Broken injected-class-name"); 4600 } 4601 } 4602} 4603 4604void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4605 SourceLocation RBraceLoc) { 4606 AdjustDeclIfTemplate(TagD); 4607 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4608 Tag->setRBraceLoc(RBraceLoc); 4609 4610 if (isa<CXXRecordDecl>(Tag)) 4611 FieldCollector->FinishClass(); 4612 4613 // Exit this scope of this tag's definition. 4614 PopDeclContext(); 4615 4616 // Notify the consumer that we've defined a tag. 4617 Consumer.HandleTagDeclDefinition(Tag); 4618} 4619 4620// Note that FieldName may be null for anonymous bitfields. 4621bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4622 QualType FieldTy, const Expr *BitWidth, 4623 bool *ZeroWidth) { 4624 // Default to true; that shouldn't confuse checks for emptiness 4625 if (ZeroWidth) 4626 *ZeroWidth = true; 4627 4628 // C99 6.7.2.1p4 - verify the field type. 4629 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4630 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4631 // Handle incomplete types with specific error. 4632 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4633 return true; 4634 if (FieldName) 4635 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4636 << FieldName << FieldTy << BitWidth->getSourceRange(); 4637 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4638 << FieldTy << BitWidth->getSourceRange(); 4639 } 4640 4641 // If the bit-width is type- or value-dependent, don't try to check 4642 // it now. 4643 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4644 return false; 4645 4646 llvm::APSInt Value; 4647 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4648 return true; 4649 4650 if (Value != 0 && ZeroWidth) 4651 *ZeroWidth = false; 4652 4653 // Zero-width bitfield is ok for anonymous field. 4654 if (Value == 0 && FieldName) 4655 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4656 4657 if (Value.isSigned() && Value.isNegative()) { 4658 if (FieldName) 4659 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4660 << FieldName << Value.toString(10); 4661 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4662 << Value.toString(10); 4663 } 4664 4665 if (!FieldTy->isDependentType()) { 4666 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4667 if (Value.getZExtValue() > TypeSize) { 4668 if (FieldName) 4669 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4670 << FieldName << (unsigned)TypeSize; 4671 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4672 << (unsigned)TypeSize; 4673 } 4674 } 4675 4676 return false; 4677} 4678 4679/// ActOnField - Each field of a struct/union/class is passed into this in order 4680/// to create a FieldDecl object for it. 4681Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4682 SourceLocation DeclStart, 4683 Declarator &D, ExprTy *BitfieldWidth) { 4684 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4685 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4686 AS_public); 4687 return DeclPtrTy::make(Res); 4688} 4689 4690/// HandleField - Analyze a field of a C struct or a C++ data member. 4691/// 4692FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4693 SourceLocation DeclStart, 4694 Declarator &D, Expr *BitWidth, 4695 AccessSpecifier AS) { 4696 IdentifierInfo *II = D.getIdentifier(); 4697 SourceLocation Loc = DeclStart; 4698 if (II) Loc = D.getIdentifierLoc(); 4699 4700 DeclaratorInfo *DInfo = 0; 4701 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4702 if (getLangOptions().CPlusPlus) 4703 CheckExtraCXXDefaultArguments(D); 4704 4705 DiagnoseFunctionSpecifiers(D); 4706 4707 if (D.getDeclSpec().isThreadSpecified()) 4708 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4709 4710 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4711 4712 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4713 // Maybe we will complain about the shadowed template parameter. 4714 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4715 // Just pretend that we didn't see the previous declaration. 4716 PrevDecl = 0; 4717 } 4718 4719 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4720 PrevDecl = 0; 4721 4722 bool Mutable 4723 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4724 SourceLocation TSSL = D.getSourceRange().getBegin(); 4725 FieldDecl *NewFD 4726 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4727 AS, PrevDecl, &D); 4728 if (NewFD->isInvalidDecl() && PrevDecl) { 4729 // Don't introduce NewFD into scope; there's already something 4730 // with the same name in the same scope. 4731 } else if (II) { 4732 PushOnScopeChains(NewFD, S); 4733 } else 4734 Record->addDecl(NewFD); 4735 4736 return NewFD; 4737} 4738 4739/// \brief Build a new FieldDecl and check its well-formedness. 4740/// 4741/// This routine builds a new FieldDecl given the fields name, type, 4742/// record, etc. \p PrevDecl should refer to any previous declaration 4743/// with the same name and in the same scope as the field to be 4744/// created. 4745/// 4746/// \returns a new FieldDecl. 4747/// 4748/// \todo The Declarator argument is a hack. It will be removed once 4749FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4750 DeclaratorInfo *DInfo, 4751 RecordDecl *Record, SourceLocation Loc, 4752 bool Mutable, Expr *BitWidth, 4753 SourceLocation TSSL, 4754 AccessSpecifier AS, NamedDecl *PrevDecl, 4755 Declarator *D) { 4756 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4757 bool InvalidDecl = false; 4758 if (D) InvalidDecl = D->isInvalidType(); 4759 4760 // If we receive a broken type, recover by assuming 'int' and 4761 // marking this declaration as invalid. 4762 if (T.isNull()) { 4763 InvalidDecl = true; 4764 T = Context.IntTy; 4765 } 4766 4767 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4768 // than a variably modified type. 4769 if (T->isVariablyModifiedType()) { 4770 bool SizeIsNegative; 4771 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4772 SizeIsNegative); 4773 if (!FixedTy.isNull()) { 4774 Diag(Loc, diag::warn_illegal_constant_array_size); 4775 T = FixedTy; 4776 } else { 4777 if (SizeIsNegative) 4778 Diag(Loc, diag::err_typecheck_negative_array_size); 4779 else 4780 Diag(Loc, diag::err_typecheck_field_variable_size); 4781 InvalidDecl = true; 4782 } 4783 } 4784 4785 // Fields can not have abstract class types 4786 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4787 AbstractFieldType)) 4788 InvalidDecl = true; 4789 4790 bool ZeroWidth = false; 4791 // If this is declared as a bit-field, check the bit-field. 4792 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4793 InvalidDecl = true; 4794 DeleteExpr(BitWidth); 4795 BitWidth = 0; 4796 ZeroWidth = false; 4797 } 4798 4799 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4800 BitWidth, Mutable); 4801 if (InvalidDecl) 4802 NewFD->setInvalidDecl(); 4803 4804 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4805 Diag(Loc, diag::err_duplicate_member) << II; 4806 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4807 NewFD->setInvalidDecl(); 4808 } 4809 4810 if (getLangOptions().CPlusPlus) { 4811 QualType EltTy = Context.getBaseElementType(T); 4812 4813 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4814 4815 if (!T->isPODType()) 4816 CXXRecord->setPOD(false); 4817 if (!ZeroWidth) 4818 CXXRecord->setEmpty(false); 4819 4820 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4821 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4822 4823 if (!RDecl->hasTrivialConstructor()) 4824 CXXRecord->setHasTrivialConstructor(false); 4825 if (!RDecl->hasTrivialCopyConstructor()) 4826 CXXRecord->setHasTrivialCopyConstructor(false); 4827 if (!RDecl->hasTrivialCopyAssignment()) 4828 CXXRecord->setHasTrivialCopyAssignment(false); 4829 if (!RDecl->hasTrivialDestructor()) 4830 CXXRecord->setHasTrivialDestructor(false); 4831 4832 // C++ 9.5p1: An object of a class with a non-trivial 4833 // constructor, a non-trivial copy constructor, a non-trivial 4834 // destructor, or a non-trivial copy assignment operator 4835 // cannot be a member of a union, nor can an array of such 4836 // objects. 4837 // TODO: C++0x alters this restriction significantly. 4838 if (Record->isUnion()) { 4839 // We check for copy constructors before constructors 4840 // because otherwise we'll never get complaints about 4841 // copy constructors. 4842 4843 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4844 4845 CXXSpecialMember member; 4846 if (!RDecl->hasTrivialCopyConstructor()) 4847 member = CXXCopyConstructor; 4848 else if (!RDecl->hasTrivialConstructor()) 4849 member = CXXDefaultConstructor; 4850 else if (!RDecl->hasTrivialCopyAssignment()) 4851 member = CXXCopyAssignment; 4852 else if (!RDecl->hasTrivialDestructor()) 4853 member = CXXDestructor; 4854 else 4855 member = invalid; 4856 4857 if (member != invalid) { 4858 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4859 DiagnoseNontrivial(RT, member); 4860 NewFD->setInvalidDecl(); 4861 } 4862 } 4863 } 4864 } 4865 4866 // FIXME: We need to pass in the attributes given an AST 4867 // representation, not a parser representation. 4868 if (D) 4869 // FIXME: What to pass instead of TUScope? 4870 ProcessDeclAttributes(TUScope, NewFD, *D); 4871 4872 if (T.isObjCGCWeak()) 4873 Diag(Loc, diag::warn_attribute_weak_on_field); 4874 4875 NewFD->setAccess(AS); 4876 4877 // C++ [dcl.init.aggr]p1: 4878 // An aggregate is an array or a class (clause 9) with [...] no 4879 // private or protected non-static data members (clause 11). 4880 // A POD must be an aggregate. 4881 if (getLangOptions().CPlusPlus && 4882 (AS == AS_private || AS == AS_protected)) { 4883 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4884 CXXRecord->setAggregate(false); 4885 CXXRecord->setPOD(false); 4886 } 4887 4888 return NewFD; 4889} 4890 4891/// DiagnoseNontrivial - Given that a class has a non-trivial 4892/// special member, figure out why. 4893void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4894 QualType QT(T, 0U); 4895 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4896 4897 // Check whether the member was user-declared. 4898 switch (member) { 4899 case CXXDefaultConstructor: 4900 if (RD->hasUserDeclaredConstructor()) { 4901 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4902 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4903 if (!ci->isImplicitlyDefined(Context)) { 4904 SourceLocation CtorLoc = ci->getLocation(); 4905 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4906 return; 4907 } 4908 4909 assert(0 && "found no user-declared constructors"); 4910 return; 4911 } 4912 break; 4913 4914 case CXXCopyConstructor: 4915 if (RD->hasUserDeclaredCopyConstructor()) { 4916 SourceLocation CtorLoc = 4917 RD->getCopyConstructor(Context, 0)->getLocation(); 4918 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4919 return; 4920 } 4921 break; 4922 4923 case CXXCopyAssignment: 4924 if (RD->hasUserDeclaredCopyAssignment()) { 4925 // FIXME: this should use the location of the copy 4926 // assignment, not the type. 4927 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4928 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4929 return; 4930 } 4931 break; 4932 4933 case CXXDestructor: 4934 if (RD->hasUserDeclaredDestructor()) { 4935 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4936 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4937 return; 4938 } 4939 break; 4940 } 4941 4942 typedef CXXRecordDecl::base_class_iterator base_iter; 4943 4944 // Virtual bases and members inhibit trivial copying/construction, 4945 // but not trivial destruction. 4946 if (member != CXXDestructor) { 4947 // Check for virtual bases. vbases includes indirect virtual bases, 4948 // so we just iterate through the direct bases. 4949 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4950 if (bi->isVirtual()) { 4951 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4952 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4953 return; 4954 } 4955 4956 // Check for virtual methods. 4957 typedef CXXRecordDecl::method_iterator meth_iter; 4958 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4959 ++mi) { 4960 if (mi->isVirtual()) { 4961 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4962 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4963 return; 4964 } 4965 } 4966 } 4967 4968 bool (CXXRecordDecl::*hasTrivial)() const; 4969 switch (member) { 4970 case CXXDefaultConstructor: 4971 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4972 case CXXCopyConstructor: 4973 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4974 case CXXCopyAssignment: 4975 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4976 case CXXDestructor: 4977 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4978 default: 4979 assert(0 && "unexpected special member"); return; 4980 } 4981 4982 // Check for nontrivial bases (and recurse). 4983 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4984 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4985 assert(BaseRT); 4986 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4987 if (!(BaseRecTy->*hasTrivial)()) { 4988 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4989 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4990 DiagnoseNontrivial(BaseRT, member); 4991 return; 4992 } 4993 } 4994 4995 // Check for nontrivial members (and recurse). 4996 typedef RecordDecl::field_iterator field_iter; 4997 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4998 ++fi) { 4999 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5000 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5001 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5002 5003 if (!(EltRD->*hasTrivial)()) { 5004 SourceLocation FLoc = (*fi)->getLocation(); 5005 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5006 DiagnoseNontrivial(EltRT, member); 5007 return; 5008 } 5009 } 5010 } 5011 5012 assert(0 && "found no explanation for non-trivial member"); 5013} 5014 5015/// TranslateIvarVisibility - Translate visibility from a token ID to an 5016/// AST enum value. 5017static ObjCIvarDecl::AccessControl 5018TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5019 switch (ivarVisibility) { 5020 default: assert(0 && "Unknown visitibility kind"); 5021 case tok::objc_private: return ObjCIvarDecl::Private; 5022 case tok::objc_public: return ObjCIvarDecl::Public; 5023 case tok::objc_protected: return ObjCIvarDecl::Protected; 5024 case tok::objc_package: return ObjCIvarDecl::Package; 5025 } 5026} 5027 5028/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5029/// in order to create an IvarDecl object for it. 5030Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5031 SourceLocation DeclStart, 5032 DeclPtrTy IntfDecl, 5033 Declarator &D, ExprTy *BitfieldWidth, 5034 tok::ObjCKeywordKind Visibility) { 5035 5036 IdentifierInfo *II = D.getIdentifier(); 5037 Expr *BitWidth = (Expr*)BitfieldWidth; 5038 SourceLocation Loc = DeclStart; 5039 if (II) Loc = D.getIdentifierLoc(); 5040 5041 // FIXME: Unnamed fields can be handled in various different ways, for 5042 // example, unnamed unions inject all members into the struct namespace! 5043 5044 DeclaratorInfo *DInfo = 0; 5045 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5046 5047 if (BitWidth) { 5048 // 6.7.2.1p3, 6.7.2.1p4 5049 if (VerifyBitField(Loc, II, T, BitWidth)) { 5050 D.setInvalidType(); 5051 DeleteExpr(BitWidth); 5052 BitWidth = 0; 5053 } 5054 } else { 5055 // Not a bitfield. 5056 5057 // validate II. 5058 5059 } 5060 5061 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5062 // than a variably modified type. 5063 if (T->isVariablyModifiedType()) { 5064 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5065 D.setInvalidType(); 5066 } 5067 5068 // Get the visibility (access control) for this ivar. 5069 ObjCIvarDecl::AccessControl ac = 5070 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5071 : ObjCIvarDecl::None; 5072 // Must set ivar's DeclContext to its enclosing interface. 5073 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5074 DeclContext *EnclosingContext; 5075 if (ObjCImplementationDecl *IMPDecl = 5076 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5077 // Case of ivar declared in an implementation. Context is that of its class. 5078 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5079 assert(IDecl && "No class- ActOnIvar"); 5080 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5081 } else 5082 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5083 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5084 5085 // Construct the decl. 5086 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5087 EnclosingContext, Loc, II, T, 5088 DInfo, ac, (Expr *)BitfieldWidth); 5089 5090 if (II) { 5091 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5092 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5093 && !isa<TagDecl>(PrevDecl)) { 5094 Diag(Loc, diag::err_duplicate_member) << II; 5095 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5096 NewID->setInvalidDecl(); 5097 } 5098 } 5099 5100 // Process attributes attached to the ivar. 5101 ProcessDeclAttributes(S, NewID, D); 5102 5103 if (D.isInvalidType()) 5104 NewID->setInvalidDecl(); 5105 5106 if (II) { 5107 // FIXME: When interfaces are DeclContexts, we'll need to add 5108 // these to the interface. 5109 S->AddDecl(DeclPtrTy::make(NewID)); 5110 IdResolver.AddDecl(NewID); 5111 } 5112 5113 return DeclPtrTy::make(NewID); 5114} 5115 5116void Sema::ActOnFields(Scope* S, 5117 SourceLocation RecLoc, DeclPtrTy RecDecl, 5118 DeclPtrTy *Fields, unsigned NumFields, 5119 SourceLocation LBrac, SourceLocation RBrac, 5120 AttributeList *Attr) { 5121 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5122 assert(EnclosingDecl && "missing record or interface decl"); 5123 5124 // If the decl this is being inserted into is invalid, then it may be a 5125 // redeclaration or some other bogus case. Don't try to add fields to it. 5126 if (EnclosingDecl->isInvalidDecl()) { 5127 // FIXME: Deallocate fields? 5128 return; 5129 } 5130 5131 5132 // Verify that all the fields are okay. 5133 unsigned NumNamedMembers = 0; 5134 llvm::SmallVector<FieldDecl*, 32> RecFields; 5135 5136 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5137 for (unsigned i = 0; i != NumFields; ++i) { 5138 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5139 5140 // Get the type for the field. 5141 Type *FDTy = FD->getType().getTypePtr(); 5142 5143 if (!FD->isAnonymousStructOrUnion()) { 5144 // Remember all fields written by the user. 5145 RecFields.push_back(FD); 5146 } 5147 5148 // If the field is already invalid for some reason, don't emit more 5149 // diagnostics about it. 5150 if (FD->isInvalidDecl()) 5151 continue; 5152 5153 // C99 6.7.2.1p2: 5154 // A structure or union shall not contain a member with 5155 // incomplete or function type (hence, a structure shall not 5156 // contain an instance of itself, but may contain a pointer to 5157 // an instance of itself), except that the last member of a 5158 // structure with more than one named member may have incomplete 5159 // array type; such a structure (and any union containing, 5160 // possibly recursively, a member that is such a structure) 5161 // shall not be a member of a structure or an element of an 5162 // array. 5163 if (FDTy->isFunctionType()) { 5164 // Field declared as a function. 5165 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5166 << FD->getDeclName(); 5167 FD->setInvalidDecl(); 5168 EnclosingDecl->setInvalidDecl(); 5169 continue; 5170 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5171 Record && Record->isStruct()) { 5172 // Flexible array member. 5173 if (NumNamedMembers < 1) { 5174 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5175 << FD->getDeclName(); 5176 FD->setInvalidDecl(); 5177 EnclosingDecl->setInvalidDecl(); 5178 continue; 5179 } 5180 // Okay, we have a legal flexible array member at the end of the struct. 5181 if (Record) 5182 Record->setHasFlexibleArrayMember(true); 5183 } else if (!FDTy->isDependentType() && 5184 RequireCompleteType(FD->getLocation(), FD->getType(), 5185 diag::err_field_incomplete)) { 5186 // Incomplete type 5187 FD->setInvalidDecl(); 5188 EnclosingDecl->setInvalidDecl(); 5189 continue; 5190 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5191 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5192 // If this is a member of a union, then entire union becomes "flexible". 5193 if (Record && Record->isUnion()) { 5194 Record->setHasFlexibleArrayMember(true); 5195 } else { 5196 // If this is a struct/class and this is not the last element, reject 5197 // it. Note that GCC supports variable sized arrays in the middle of 5198 // structures. 5199 if (i != NumFields-1) 5200 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5201 << FD->getDeclName() << FD->getType(); 5202 else { 5203 // We support flexible arrays at the end of structs in 5204 // other structs as an extension. 5205 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5206 << FD->getDeclName(); 5207 if (Record) 5208 Record->setHasFlexibleArrayMember(true); 5209 } 5210 } 5211 } 5212 if (Record && FDTTy->getDecl()->hasObjectMember()) 5213 Record->setHasObjectMember(true); 5214 } else if (FDTy->isObjCInterfaceType()) { 5215 /// A field cannot be an Objective-c object 5216 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5217 FD->setInvalidDecl(); 5218 EnclosingDecl->setInvalidDecl(); 5219 continue; 5220 } else if (getLangOptions().ObjC1 && 5221 getLangOptions().getGCMode() != LangOptions::NonGC && 5222 Record && 5223 (FD->getType()->isObjCObjectPointerType() || 5224 FD->getType().isObjCGCStrong())) 5225 Record->setHasObjectMember(true); 5226 // Keep track of the number of named members. 5227 if (FD->getIdentifier()) 5228 ++NumNamedMembers; 5229 } 5230 5231 // Okay, we successfully defined 'Record'. 5232 if (Record) { 5233 Record->completeDefinition(Context); 5234 } else { 5235 ObjCIvarDecl **ClsFields = 5236 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5237 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5238 ID->setIVarList(ClsFields, RecFields.size(), Context); 5239 ID->setLocEnd(RBrac); 5240 // Add ivar's to class's DeclContext. 5241 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5242 ClsFields[i]->setLexicalDeclContext(ID); 5243 ID->addDecl(ClsFields[i]); 5244 } 5245 // Must enforce the rule that ivars in the base classes may not be 5246 // duplicates. 5247 if (ID->getSuperClass()) { 5248 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5249 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5250 ObjCIvarDecl* Ivar = (*IVI); 5251 5252 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5253 ObjCIvarDecl* prevIvar = 5254 ID->getSuperClass()->lookupInstanceVariable(II); 5255 if (prevIvar) { 5256 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5257 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5258 } 5259 } 5260 } 5261 } 5262 } else if (ObjCImplementationDecl *IMPDecl = 5263 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5264 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5265 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5266 // Ivar declared in @implementation never belongs to the implementation. 5267 // Only it is in implementation's lexical context. 5268 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5269 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5270 } 5271 } 5272 5273 if (Attr) 5274 ProcessDeclAttributeList(S, Record, Attr); 5275} 5276 5277EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5278 EnumConstantDecl *LastEnumConst, 5279 SourceLocation IdLoc, 5280 IdentifierInfo *Id, 5281 ExprArg val) { 5282 Expr *Val = (Expr *)val.get(); 5283 5284 llvm::APSInt EnumVal(32); 5285 QualType EltTy; 5286 if (Val && !Val->isTypeDependent()) { 5287 // Make sure to promote the operand type to int. 5288 UsualUnaryConversions(Val); 5289 if (Val != val.get()) { 5290 val.release(); 5291 val = Val; 5292 } 5293 5294 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5295 SourceLocation ExpLoc; 5296 if (!Val->isValueDependent() && 5297 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5298 Val = 0; 5299 } else { 5300 EltTy = Val->getType(); 5301 } 5302 } 5303 5304 if (!Val) { 5305 if (LastEnumConst) { 5306 // Assign the last value + 1. 5307 EnumVal = LastEnumConst->getInitVal(); 5308 ++EnumVal; 5309 5310 // Check for overflow on increment. 5311 if (EnumVal < LastEnumConst->getInitVal()) 5312 Diag(IdLoc, diag::warn_enum_value_overflow); 5313 5314 EltTy = LastEnumConst->getType(); 5315 } else { 5316 // First value, set to zero. 5317 EltTy = Context.IntTy; 5318 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5319 } 5320 } 5321 5322 val.release(); 5323 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5324 Val, EnumVal); 5325} 5326 5327 5328Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5329 DeclPtrTy lastEnumConst, 5330 SourceLocation IdLoc, 5331 IdentifierInfo *Id, 5332 SourceLocation EqualLoc, ExprTy *val) { 5333 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5334 EnumConstantDecl *LastEnumConst = 5335 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5336 Expr *Val = static_cast<Expr*>(val); 5337 5338 // The scope passed in may not be a decl scope. Zip up the scope tree until 5339 // we find one that is. 5340 S = getNonFieldDeclScope(S); 5341 5342 // Verify that there isn't already something declared with this name in this 5343 // scope. 5344 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5345 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5346 // Maybe we will complain about the shadowed template parameter. 5347 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5348 // Just pretend that we didn't see the previous declaration. 5349 PrevDecl = 0; 5350 } 5351 5352 if (PrevDecl) { 5353 // When in C++, we may get a TagDecl with the same name; in this case the 5354 // enum constant will 'hide' the tag. 5355 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5356 "Received TagDecl when not in C++!"); 5357 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5358 if (isa<EnumConstantDecl>(PrevDecl)) 5359 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5360 else 5361 Diag(IdLoc, diag::err_redefinition) << Id; 5362 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5363 if (Val) Val->Destroy(Context); 5364 return DeclPtrTy(); 5365 } 5366 } 5367 5368 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5369 IdLoc, Id, Owned(Val)); 5370 5371 // Register this decl in the current scope stack. 5372 if (New) 5373 PushOnScopeChains(New, S); 5374 5375 return DeclPtrTy::make(New); 5376} 5377 5378void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5379 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5380 DeclPtrTy *Elements, unsigned NumElements, 5381 Scope *S, AttributeList *Attr) { 5382 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5383 QualType EnumType = Context.getTypeDeclType(Enum); 5384 5385 if (Attr) 5386 ProcessDeclAttributeList(S, Enum, Attr); 5387 5388 // TODO: If the result value doesn't fit in an int, it must be a long or long 5389 // long value. ISO C does not support this, but GCC does as an extension, 5390 // emit a warning. 5391 unsigned IntWidth = Context.Target.getIntWidth(); 5392 unsigned CharWidth = Context.Target.getCharWidth(); 5393 unsigned ShortWidth = Context.Target.getShortWidth(); 5394 5395 // Verify that all the values are okay, compute the size of the values, and 5396 // reverse the list. 5397 unsigned NumNegativeBits = 0; 5398 unsigned NumPositiveBits = 0; 5399 5400 // Keep track of whether all elements have type int. 5401 bool AllElementsInt = true; 5402 5403 for (unsigned i = 0; i != NumElements; ++i) { 5404 EnumConstantDecl *ECD = 5405 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5406 if (!ECD) continue; // Already issued a diagnostic. 5407 5408 // If the enum value doesn't fit in an int, emit an extension warning. 5409 const llvm::APSInt &InitVal = ECD->getInitVal(); 5410 assert(InitVal.getBitWidth() >= IntWidth && 5411 "Should have promoted value to int"); 5412 if (InitVal.getBitWidth() > IntWidth) { 5413 llvm::APSInt V(InitVal); 5414 V.trunc(IntWidth); 5415 V.extend(InitVal.getBitWidth()); 5416 if (V != InitVal) 5417 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5418 << InitVal.toString(10); 5419 } 5420 5421 // Keep track of the size of positive and negative values. 5422 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5423 NumPositiveBits = std::max(NumPositiveBits, 5424 (unsigned)InitVal.getActiveBits()); 5425 else 5426 NumNegativeBits = std::max(NumNegativeBits, 5427 (unsigned)InitVal.getMinSignedBits()); 5428 5429 // Keep track of whether every enum element has type int (very commmon). 5430 if (AllElementsInt) 5431 AllElementsInt = ECD->getType() == Context.IntTy; 5432 } 5433 5434 // Figure out the type that should be used for this enum. 5435 // FIXME: Support -fshort-enums. 5436 QualType BestType; 5437 unsigned BestWidth; 5438 5439 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5440 5441 if (NumNegativeBits) { 5442 // If there is a negative value, figure out the smallest integer type (of 5443 // int/long/longlong) that fits. 5444 // If it's packed, check also if it fits a char or a short. 5445 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5446 BestType = Context.SignedCharTy; 5447 BestWidth = CharWidth; 5448 } else if (Packed && NumNegativeBits <= ShortWidth && 5449 NumPositiveBits < ShortWidth) { 5450 BestType = Context.ShortTy; 5451 BestWidth = ShortWidth; 5452 } 5453 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5454 BestType = Context.IntTy; 5455 BestWidth = IntWidth; 5456 } else { 5457 BestWidth = Context.Target.getLongWidth(); 5458 5459 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5460 BestType = Context.LongTy; 5461 else { 5462 BestWidth = Context.Target.getLongLongWidth(); 5463 5464 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5465 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5466 BestType = Context.LongLongTy; 5467 } 5468 } 5469 } else { 5470 // If there is no negative value, figure out which of uint, ulong, ulonglong 5471 // fits. 5472 // If it's packed, check also if it fits a char or a short. 5473 if (Packed && NumPositiveBits <= CharWidth) { 5474 BestType = Context.UnsignedCharTy; 5475 BestWidth = CharWidth; 5476 } else if (Packed && NumPositiveBits <= ShortWidth) { 5477 BestType = Context.UnsignedShortTy; 5478 BestWidth = ShortWidth; 5479 } 5480 else if (NumPositiveBits <= IntWidth) { 5481 BestType = Context.UnsignedIntTy; 5482 BestWidth = IntWidth; 5483 } else if (NumPositiveBits <= 5484 (BestWidth = Context.Target.getLongWidth())) { 5485 BestType = Context.UnsignedLongTy; 5486 } else { 5487 BestWidth = Context.Target.getLongLongWidth(); 5488 assert(NumPositiveBits <= BestWidth && 5489 "How could an initializer get larger than ULL?"); 5490 BestType = Context.UnsignedLongLongTy; 5491 } 5492 } 5493 5494 // Loop over all of the enumerator constants, changing their types to match 5495 // the type of the enum if needed. 5496 for (unsigned i = 0; i != NumElements; ++i) { 5497 EnumConstantDecl *ECD = 5498 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5499 if (!ECD) continue; // Already issued a diagnostic. 5500 5501 // Standard C says the enumerators have int type, but we allow, as an 5502 // extension, the enumerators to be larger than int size. If each 5503 // enumerator value fits in an int, type it as an int, otherwise type it the 5504 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5505 // that X has type 'int', not 'unsigned'. 5506 if (ECD->getType() == Context.IntTy) { 5507 // Make sure the init value is signed. 5508 llvm::APSInt IV = ECD->getInitVal(); 5509 IV.setIsSigned(true); 5510 ECD->setInitVal(IV); 5511 5512 if (getLangOptions().CPlusPlus) 5513 // C++ [dcl.enum]p4: Following the closing brace of an 5514 // enum-specifier, each enumerator has the type of its 5515 // enumeration. 5516 ECD->setType(EnumType); 5517 continue; // Already int type. 5518 } 5519 5520 // Determine whether the value fits into an int. 5521 llvm::APSInt InitVal = ECD->getInitVal(); 5522 bool FitsInInt; 5523 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5524 FitsInInt = InitVal.getActiveBits() < IntWidth; 5525 else 5526 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5527 5528 // If it fits into an integer type, force it. Otherwise force it to match 5529 // the enum decl type. 5530 QualType NewTy; 5531 unsigned NewWidth; 5532 bool NewSign; 5533 if (FitsInInt) { 5534 NewTy = Context.IntTy; 5535 NewWidth = IntWidth; 5536 NewSign = true; 5537 } else if (ECD->getType() == BestType) { 5538 // Already the right type! 5539 if (getLangOptions().CPlusPlus) 5540 // C++ [dcl.enum]p4: Following the closing brace of an 5541 // enum-specifier, each enumerator has the type of its 5542 // enumeration. 5543 ECD->setType(EnumType); 5544 continue; 5545 } else { 5546 NewTy = BestType; 5547 NewWidth = BestWidth; 5548 NewSign = BestType->isSignedIntegerType(); 5549 } 5550 5551 // Adjust the APSInt value. 5552 InitVal.extOrTrunc(NewWidth); 5553 InitVal.setIsSigned(NewSign); 5554 ECD->setInitVal(InitVal); 5555 5556 // Adjust the Expr initializer and type. 5557 if (ECD->getInitExpr()) 5558 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5559 CastExpr::CK_Unknown, 5560 ECD->getInitExpr(), 5561 /*isLvalue=*/false)); 5562 if (getLangOptions().CPlusPlus) 5563 // C++ [dcl.enum]p4: Following the closing brace of an 5564 // enum-specifier, each enumerator has the type of its 5565 // enumeration. 5566 ECD->setType(EnumType); 5567 else 5568 ECD->setType(NewTy); 5569 } 5570 5571 Enum->completeDefinition(Context, BestType); 5572} 5573 5574Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5575 ExprArg expr) { 5576 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5577 5578 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5579 Loc, AsmString); 5580 CurContext->addDecl(New); 5581 return DeclPtrTy::make(New); 5582} 5583 5584void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5585 SourceLocation PragmaLoc, 5586 SourceLocation NameLoc) { 5587 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5588 5589 if (PrevDecl) { 5590 PrevDecl->addAttr(::new (Context) WeakAttr()); 5591 } else { 5592 (void)WeakUndeclaredIdentifiers.insert( 5593 std::pair<IdentifierInfo*,WeakInfo> 5594 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5595 } 5596} 5597 5598void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5599 IdentifierInfo* AliasName, 5600 SourceLocation PragmaLoc, 5601 SourceLocation NameLoc, 5602 SourceLocation AliasNameLoc) { 5603 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5604 WeakInfo W = WeakInfo(Name, NameLoc); 5605 5606 if (PrevDecl) { 5607 if (!PrevDecl->hasAttr<AliasAttr>()) 5608 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5609 DeclApplyPragmaWeak(TUScope, ND, W); 5610 } else { 5611 (void)WeakUndeclaredIdentifiers.insert( 5612 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5613 } 5614} 5615