SemaDecl.cpp revision 8211effbd3abc5948a5d6924c87e72323016a376
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/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/Parse/DeclSpec.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31using namespace clang; 32 33/// getDeclName - Return a pretty name for the specified decl if possible, or 34/// an empty string if not. This is used for pretty crash reporting. 35std::string Sema::getDeclName(DeclTy *d) { 36 Decl *D = static_cast<Decl *>(d); 37 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 38 return DN->getQualifiedNameAsString(); 39 return ""; 40} 41 42/// \brief If the identifier refers to a type name within this scope, 43/// return the declaration of that type. 44/// 45/// This routine performs ordinary name lookup of the identifier II 46/// within the given scope, with optional C++ scope specifier SS, to 47/// determine whether the name refers to a type. If so, returns an 48/// opaque pointer (actually a QualType) corresponding to that 49/// type. Otherwise, returns NULL. 50/// 51/// If name lookup results in an ambiguity, this routine will complain 52/// and then return NULL. 53Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 54 Scope *S, const CXXScopeSpec *SS) { 55 // C++ [temp.res]p3: 56 // A qualified-id that refers to a type and in which the 57 // nested-name-specifier depends on a template-parameter (14.6.2) 58 // shall be prefixed by the keyword typename to indicate that the 59 // qualified-id denotes a type, forming an 60 // elaborated-type-specifier (7.1.5.3). 61 // 62 // We therefore do not perform any name lookup up SS is a dependent 63 // scope name. FIXME: we will need to perform a special kind of 64 // lookup if the scope specifier names a member of the current 65 // instantiation. 66 if (SS && isDependentScopeSpecifier(*SS)) 67 return 0; 68 69 NamedDecl *IIDecl = 0; 70 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 71 false, false); 72 switch (Result.getKind()) { 73 case LookupResult::NotFound: 74 case LookupResult::FoundOverloaded: 75 return 0; 76 77 case LookupResult::AmbiguousBaseSubobjectTypes: 78 case LookupResult::AmbiguousBaseSubobjects: 79 case LookupResult::AmbiguousReference: 80 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 81 return 0; 82 83 case LookupResult::Found: 84 IIDecl = Result.getAsDecl(); 85 break; 86 } 87 88 if (IIDecl) { 89 QualType T; 90 91 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 92 // Check whether we can use this type 93 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 94 95 T = Context.getTypeDeclType(TD); 96 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 97 // Check whether we can use this interface. 98 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 99 100 T = Context.getObjCInterfaceType(IDecl); 101 } else 102 return 0; 103 104 if (SS) 105 T = getQualifiedNameType(*SS, T); 106 107 return T.getAsOpaquePtr(); 108 } 109 110 return 0; 111} 112 113DeclContext *Sema::getContainingDC(DeclContext *DC) { 114 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 115 // A C++ out-of-line method will return to the file declaration context. 116 if (MD->isOutOfLineDefinition()) 117 return MD->getLexicalDeclContext(); 118 119 // A C++ inline method is parsed *after* the topmost class it was declared 120 // in is fully parsed (it's "complete"). 121 // The parsing of a C++ inline method happens at the declaration context of 122 // the topmost (non-nested) class it is lexically declared in. 123 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 124 DC = MD->getParent(); 125 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 126 DC = RD; 127 128 // Return the declaration context of the topmost class the inline method is 129 // declared in. 130 return DC; 131 } 132 133 if (isa<ObjCMethodDecl>(DC)) 134 return Context.getTranslationUnitDecl(); 135 136 return DC->getLexicalParent(); 137} 138 139void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 140 assert(getContainingDC(DC) == CurContext && 141 "The next DeclContext should be lexically contained in the current one."); 142 CurContext = DC; 143 S->setEntity(DC); 144} 145 146void Sema::PopDeclContext() { 147 assert(CurContext && "DeclContext imbalance!"); 148 149 CurContext = getContainingDC(CurContext); 150} 151 152/// \brief Determine whether we allow overloading of the function 153/// PrevDecl with another declaration. 154/// 155/// This routine determines whether overloading is possible, not 156/// whether some new function is actually an overload. It will return 157/// true in C++ (where we can always provide overloads) or, as an 158/// extension, in C when the previous function is already an 159/// overloaded function declaration or has the "overloadable" 160/// attribute. 161static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 162 if (Context.getLangOptions().CPlusPlus) 163 return true; 164 165 if (isa<OverloadedFunctionDecl>(PrevDecl)) 166 return true; 167 168 return PrevDecl->getAttr<OverloadableAttr>() != 0; 169} 170 171/// Add this decl to the scope shadowed decl chains. 172void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 173 // Move up the scope chain until we find the nearest enclosing 174 // non-transparent context. The declaration will be introduced into this 175 // scope. 176 while (S->getEntity() && 177 ((DeclContext *)S->getEntity())->isTransparentContext()) 178 S = S->getParent(); 179 180 S->AddDecl(D); 181 182 // Add scoped declarations into their context, so that they can be 183 // found later. Declarations without a context won't be inserted 184 // into any context. 185 CurContext->addDecl(D); 186 187 // C++ [basic.scope]p4: 188 // -- exactly one declaration shall declare a class name or 189 // enumeration name that is not a typedef name and the other 190 // declarations shall all refer to the same object or 191 // enumerator, or all refer to functions and function templates; 192 // in this case the class name or enumeration name is hidden. 193 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 194 // We are pushing the name of a tag (enum or class). 195 if (CurContext->getLookupContext() 196 == TD->getDeclContext()->getLookupContext()) { 197 // We're pushing the tag into the current context, which might 198 // require some reshuffling in the identifier resolver. 199 IdentifierResolver::iterator 200 I = IdResolver.begin(TD->getDeclName()), 201 IEnd = IdResolver.end(); 202 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 203 NamedDecl *PrevDecl = *I; 204 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 205 PrevDecl = *I, ++I) { 206 if (TD->declarationReplaces(*I)) { 207 // This is a redeclaration. Remove it from the chain and 208 // break out, so that we'll add in the shadowed 209 // declaration. 210 S->RemoveDecl(*I); 211 if (PrevDecl == *I) { 212 IdResolver.RemoveDecl(*I); 213 IdResolver.AddDecl(TD); 214 return; 215 } else { 216 IdResolver.RemoveDecl(*I); 217 break; 218 } 219 } 220 } 221 222 // There is already a declaration with the same name in the same 223 // scope, which is not a tag declaration. It must be found 224 // before we find the new declaration, so insert the new 225 // declaration at the end of the chain. 226 IdResolver.AddShadowedDecl(TD, PrevDecl); 227 228 return; 229 } 230 } 231 } else if (isa<FunctionDecl>(D) && 232 AllowOverloadingOfFunction(D, Context)) { 233 // We are pushing the name of a function, which might be an 234 // overloaded name. 235 FunctionDecl *FD = cast<FunctionDecl>(D); 236 IdentifierResolver::iterator Redecl 237 = std::find_if(IdResolver.begin(FD->getDeclName()), 238 IdResolver.end(), 239 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 240 FD)); 241 if (Redecl != IdResolver.end() && S->isDeclScope(*Redecl)) { 242 // There is already a declaration of a function on our 243 // IdResolver chain. Replace it with this declaration. 244 S->RemoveDecl(*Redecl); 245 IdResolver.RemoveDecl(*Redecl); 246 } 247 } 248 249 IdResolver.AddDecl(D); 250} 251 252void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 253 if (S->decl_empty()) return; 254 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 255 "Scope shouldn't contain decls!"); 256 257 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 258 I != E; ++I) { 259 Decl *TmpD = static_cast<Decl*>(*I); 260 assert(TmpD && "This decl didn't get pushed??"); 261 262 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 263 NamedDecl *D = cast<NamedDecl>(TmpD); 264 265 if (!D->getDeclName()) continue; 266 267 // Remove this name from our lexical scope. 268 IdResolver.RemoveDecl(D); 269 } 270} 271 272/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 273/// return 0 if one not found. 274ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 275 // The third "scope" argument is 0 since we aren't enabling lazy built-in 276 // creation from this context. 277 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 278 279 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 280} 281 282/// getNonFieldDeclScope - Retrieves the innermost scope, starting 283/// from S, where a non-field would be declared. This routine copes 284/// with the difference between C and C++ scoping rules in structs and 285/// unions. For example, the following code is well-formed in C but 286/// ill-formed in C++: 287/// @code 288/// struct S6 { 289/// enum { BAR } e; 290/// }; 291/// 292/// void test_S6() { 293/// struct S6 a; 294/// a.e = BAR; 295/// } 296/// @endcode 297/// For the declaration of BAR, this routine will return a different 298/// scope. The scope S will be the scope of the unnamed enumeration 299/// within S6. In C++, this routine will return the scope associated 300/// with S6, because the enumeration's scope is a transparent 301/// context but structures can contain non-field names. In C, this 302/// routine will return the translation unit scope, since the 303/// enumeration's scope is a transparent context and structures cannot 304/// contain non-field names. 305Scope *Sema::getNonFieldDeclScope(Scope *S) { 306 while (((S->getFlags() & Scope::DeclScope) == 0) || 307 (S->getEntity() && 308 ((DeclContext *)S->getEntity())->isTransparentContext()) || 309 (S->isClassScope() && !getLangOptions().CPlusPlus)) 310 S = S->getParent(); 311 return S; 312} 313 314void Sema::InitBuiltinVaListType() { 315 if (!Context.getBuiltinVaListType().isNull()) 316 return; 317 318 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 319 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 320 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 321 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 322} 323 324/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 325/// file scope. lazily create a decl for it. ForRedeclaration is true 326/// if we're creating this built-in in anticipation of redeclaring the 327/// built-in. 328NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 329 Scope *S, bool ForRedeclaration, 330 SourceLocation Loc) { 331 Builtin::ID BID = (Builtin::ID)bid; 332 333 if (Context.BuiltinInfo.hasVAListUse(BID)) 334 InitBuiltinVaListType(); 335 336 Builtin::Context::GetBuiltinTypeError Error; 337 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 338 switch (Error) { 339 case Builtin::Context::GE_None: 340 // Okay 341 break; 342 343 case Builtin::Context::GE_Missing_FILE: 344 if (ForRedeclaration) 345 Diag(Loc, diag::err_implicit_decl_requires_stdio) 346 << Context.BuiltinInfo.GetName(BID); 347 return 0; 348 } 349 350 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 351 Diag(Loc, diag::ext_implicit_lib_function_decl) 352 << Context.BuiltinInfo.GetName(BID) 353 << R; 354 if (Context.BuiltinInfo.getHeaderName(BID) && 355 Diags.getDiagnosticMapping(diag::ext_implicit_lib_function_decl) 356 != diag::MAP_IGNORE) 357 Diag(Loc, diag::note_please_include_header) 358 << Context.BuiltinInfo.getHeaderName(BID) 359 << Context.BuiltinInfo.GetName(BID); 360 } 361 362 FunctionDecl *New = FunctionDecl::Create(Context, 363 Context.getTranslationUnitDecl(), 364 Loc, II, R, 365 FunctionDecl::Extern, false, 366 /*hasPrototype=*/true); 367 New->setImplicit(); 368 369 // Create Decl objects for each parameter, adding them to the 370 // FunctionDecl. 371 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 372 llvm::SmallVector<ParmVarDecl*, 16> Params; 373 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 374 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 375 FT->getArgType(i), VarDecl::None, 0)); 376 New->setParams(Context, &Params[0], Params.size()); 377 } 378 379 AddKnownFunctionAttributes(New); 380 381 // TUScope is the translation-unit scope to insert this function into. 382 // FIXME: This is hideous. We need to teach PushOnScopeChains to 383 // relate Scopes to DeclContexts, and probably eliminate CurContext 384 // entirely, but we're not there yet. 385 DeclContext *SavedContext = CurContext; 386 CurContext = Context.getTranslationUnitDecl(); 387 PushOnScopeChains(New, TUScope); 388 CurContext = SavedContext; 389 return New; 390} 391 392/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 393/// everything from the standard library is defined. 394NamespaceDecl *Sema::GetStdNamespace() { 395 if (!StdNamespace) { 396 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 397 DeclContext *Global = Context.getTranslationUnitDecl(); 398 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 399 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 400 } 401 return StdNamespace; 402} 403 404/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 405/// same name and scope as a previous declaration 'Old'. Figure out 406/// how to resolve this situation, merging decls or emitting 407/// diagnostics as appropriate. Returns true if there was an error, 408/// false otherwise. 409/// 410bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 411 bool objc_types = false; 412 // Allow multiple definitions for ObjC built-in typedefs. 413 // FIXME: Verify the underlying types are equivalent! 414 if (getLangOptions().ObjC1) { 415 const IdentifierInfo *TypeID = New->getIdentifier(); 416 switch (TypeID->getLength()) { 417 default: break; 418 case 2: 419 if (!TypeID->isStr("id")) 420 break; 421 Context.setObjCIdType(New); 422 objc_types = true; 423 break; 424 case 5: 425 if (!TypeID->isStr("Class")) 426 break; 427 Context.setObjCClassType(New); 428 objc_types = true; 429 return false; 430 case 3: 431 if (!TypeID->isStr("SEL")) 432 break; 433 Context.setObjCSelType(New); 434 objc_types = true; 435 return false; 436 case 8: 437 if (!TypeID->isStr("Protocol")) 438 break; 439 Context.setObjCProtoType(New->getUnderlyingType()); 440 objc_types = true; 441 return false; 442 } 443 // Fall through - the typedef name was not a builtin type. 444 } 445 // Verify the old decl was also a type. 446 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 447 if (!Old) { 448 Diag(New->getLocation(), diag::err_redefinition_different_kind) 449 << New->getDeclName(); 450 if (!objc_types) 451 Diag(OldD->getLocation(), diag::note_previous_definition); 452 return true; 453 } 454 455 // Determine the "old" type we'll use for checking and diagnostics. 456 QualType OldType; 457 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 458 OldType = OldTypedef->getUnderlyingType(); 459 else 460 OldType = Context.getTypeDeclType(Old); 461 462 // If the typedef types are not identical, reject them in all languages and 463 // with any extensions enabled. 464 465 if (OldType != New->getUnderlyingType() && 466 Context.getCanonicalType(OldType) != 467 Context.getCanonicalType(New->getUnderlyingType())) { 468 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 469 << New->getUnderlyingType() << OldType; 470 if (!objc_types) 471 Diag(Old->getLocation(), diag::note_previous_definition); 472 return true; 473 } 474 if (objc_types) return false; 475 if (getLangOptions().Microsoft) return false; 476 477 // C++ [dcl.typedef]p2: 478 // In a given non-class scope, a typedef specifier can be used to 479 // redefine the name of any type declared in that scope to refer 480 // to the type to which it already refers. 481 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 482 return false; 483 484 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 485 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 486 // *either* declaration is in a system header. The code below implements 487 // this adhoc compatibility rule. FIXME: The following code will not 488 // work properly when compiling ".i" files (containing preprocessed output). 489 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 490 SourceManager &SrcMgr = Context.getSourceManager(); 491 if (SrcMgr.isInSystemHeader(Old->getLocation())) 492 return false; 493 if (SrcMgr.isInSystemHeader(New->getLocation())) 494 return false; 495 } 496 497 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 498 Diag(Old->getLocation(), diag::note_previous_definition); 499 return true; 500} 501 502/// DeclhasAttr - returns true if decl Declaration already has the target 503/// attribute. 504static bool DeclHasAttr(const Decl *decl, const Attr *target) { 505 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 506 if (attr->getKind() == target->getKind()) 507 return true; 508 509 return false; 510} 511 512/// MergeAttributes - append attributes from the Old decl to the New one. 513static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 514 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 515 516 while (attr) { 517 Attr *tmp = attr; 518 attr = attr->getNext(); 519 520 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 521 tmp->setInherited(true); 522 New->addAttr(tmp); 523 } else { 524 tmp->setNext(0); 525 tmp->Destroy(C); 526 } 527 } 528 529 Old->invalidateAttrs(); 530} 531 532/// Used in MergeFunctionDecl to keep track of function parameters in 533/// C. 534struct GNUCompatibleParamWarning { 535 ParmVarDecl *OldParm; 536 ParmVarDecl *NewParm; 537 QualType PromotedType; 538}; 539 540/// MergeFunctionDecl - We just parsed a function 'New' from 541/// declarator D which has the same name and scope as a previous 542/// declaration 'Old'. Figure out how to resolve this situation, 543/// merging decls or emitting diagnostics as appropriate. 544/// 545/// In C++, New and Old must be declarations that are not 546/// overloaded. Use IsOverload to determine whether New and Old are 547/// overloaded, and to select the Old declaration that New should be 548/// merged with. 549/// 550/// Returns true if there was an error, false otherwise. 551bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 552 assert(!isa<OverloadedFunctionDecl>(OldD) && 553 "Cannot merge with an overloaded function declaration"); 554 555 // Verify the old decl was also a function. 556 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 557 if (!Old) { 558 Diag(New->getLocation(), diag::err_redefinition_different_kind) 559 << New->getDeclName(); 560 Diag(OldD->getLocation(), diag::note_previous_definition); 561 return true; 562 } 563 564 // Determine whether the previous declaration was a definition, 565 // implicit declaration, or a declaration. 566 diag::kind PrevDiag; 567 if (Old->isThisDeclarationADefinition()) 568 PrevDiag = diag::note_previous_definition; 569 else if (Old->isImplicit()) 570 PrevDiag = diag::note_previous_implicit_declaration; 571 else 572 PrevDiag = diag::note_previous_declaration; 573 574 QualType OldQType = Context.getCanonicalType(Old->getType()); 575 QualType NewQType = Context.getCanonicalType(New->getType()); 576 577 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 578 New->getStorageClass() == FunctionDecl::Static && 579 Old->getStorageClass() != FunctionDecl::Static) { 580 Diag(New->getLocation(), diag::err_static_non_static) 581 << New; 582 Diag(Old->getLocation(), PrevDiag); 583 return true; 584 } 585 586 if (getLangOptions().CPlusPlus) { 587 // (C++98 13.1p2): 588 // Certain function declarations cannot be overloaded: 589 // -- Function declarations that differ only in the return type 590 // cannot be overloaded. 591 QualType OldReturnType 592 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 593 QualType NewReturnType 594 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 595 if (OldReturnType != NewReturnType) { 596 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 597 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 598 return true; 599 } 600 601 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 602 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 603 if (OldMethod && NewMethod && 604 OldMethod->getLexicalDeclContext() == 605 NewMethod->getLexicalDeclContext()) { 606 // -- Member function declarations with the same name and the 607 // same parameter types cannot be overloaded if any of them 608 // is a static member function declaration. 609 if (OldMethod->isStatic() || NewMethod->isStatic()) { 610 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 611 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 612 return true; 613 } 614 615 // C++ [class.mem]p1: 616 // [...] A member shall not be declared twice in the 617 // member-specification, except that a nested class or member 618 // class template can be declared and then later defined. 619 unsigned NewDiag; 620 if (isa<CXXConstructorDecl>(OldMethod)) 621 NewDiag = diag::err_constructor_redeclared; 622 else if (isa<CXXDestructorDecl>(NewMethod)) 623 NewDiag = diag::err_destructor_redeclared; 624 else if (isa<CXXConversionDecl>(NewMethod)) 625 NewDiag = diag::err_conv_function_redeclared; 626 else 627 NewDiag = diag::err_member_redeclared; 628 629 Diag(New->getLocation(), NewDiag); 630 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 631 } 632 633 // (C++98 8.3.5p3): 634 // All declarations for a function shall agree exactly in both the 635 // return type and the parameter-type-list. 636 if (OldQType == NewQType) 637 return MergeCompatibleFunctionDecls(New, Old); 638 639 // Fall through for conflicting redeclarations and redefinitions. 640 } 641 642 // C: Function types need to be compatible, not identical. This handles 643 // duplicate function decls like "void f(int); void f(enum X);" properly. 644 if (!getLangOptions().CPlusPlus && 645 Context.typesAreCompatible(OldQType, NewQType)) { 646 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 647 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 648 const FunctionProtoType *OldProto = 0; 649 if (isa<FunctionNoProtoType>(NewFuncType) && 650 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 651 // The old declaration provided a function prototype, but the 652 // new declaration does not. Merge in the prototype. 653 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 654 OldProto->arg_type_end()); 655 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 656 &ParamTypes[0], ParamTypes.size(), 657 OldProto->isVariadic(), 658 OldProto->getTypeQuals()); 659 New->setType(NewQType); 660 New->setInheritedPrototype(); 661 662 // Synthesize a parameter for each argument type. 663 llvm::SmallVector<ParmVarDecl*, 16> Params; 664 for (FunctionProtoType::arg_type_iterator 665 ParamType = OldProto->arg_type_begin(), 666 ParamEnd = OldProto->arg_type_end(); 667 ParamType != ParamEnd; ++ParamType) { 668 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 669 SourceLocation(), 0, 670 *ParamType, VarDecl::None, 671 0); 672 Param->setImplicit(); 673 Params.push_back(Param); 674 } 675 676 New->setParams(Context, &Params[0], Params.size()); 677 } 678 679 return MergeCompatibleFunctionDecls(New, Old); 680 } 681 682 // GNU C permits a K&R definition to follow a prototype declaration 683 // if the declared types of the parameters in the K&R definition 684 // match the types in the prototype declaration, even when the 685 // promoted types of the parameters from the K&R definition differ 686 // from the types in the prototype. GCC then keeps the types from 687 // the prototype. 688 if (!getLangOptions().CPlusPlus && 689 !getLangOptions().NoExtensions && 690 Old->hasPrototype() && !New->hasPrototype() && 691 New->getType()->getAsFunctionProtoType() && 692 Old->getNumParams() == New->getNumParams()) { 693 llvm::SmallVector<QualType, 16> ArgTypes; 694 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 695 const FunctionProtoType *OldProto 696 = Old->getType()->getAsFunctionProtoType(); 697 const FunctionProtoType *NewProto 698 = New->getType()->getAsFunctionProtoType(); 699 700 // Determine whether this is the GNU C extension. 701 bool GNUCompatible = 702 Context.typesAreCompatible(OldProto->getResultType(), 703 NewProto->getResultType()) && 704 (OldProto->isVariadic() == NewProto->isVariadic()); 705 for (unsigned Idx = 0, End = Old->getNumParams(); 706 GNUCompatible && Idx != End; ++Idx) { 707 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 708 ParmVarDecl *NewParm = New->getParamDecl(Idx); 709 if (Context.typesAreCompatible(OldParm->getType(), 710 NewProto->getArgType(Idx))) { 711 ArgTypes.push_back(NewParm->getType()); 712 } else if (Context.typesAreCompatible(OldParm->getType(), 713 NewParm->getType())) { 714 GNUCompatibleParamWarning Warn 715 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 716 Warnings.push_back(Warn); 717 ArgTypes.push_back(NewParm->getType()); 718 } else 719 GNUCompatible = false; 720 } 721 722 if (GNUCompatible) { 723 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 724 Diag(Warnings[Warn].NewParm->getLocation(), 725 diag::ext_param_promoted_not_compatible_with_prototype) 726 << Warnings[Warn].PromotedType 727 << Warnings[Warn].OldParm->getType(); 728 Diag(Warnings[Warn].OldParm->getLocation(), 729 diag::note_previous_declaration); 730 } 731 732 New->setType(Context.getFunctionType(NewProto->getResultType(), 733 &ArgTypes[0], ArgTypes.size(), 734 NewProto->isVariadic(), 735 NewProto->getTypeQuals())); 736 return MergeCompatibleFunctionDecls(New, Old); 737 } 738 739 // Fall through to diagnose conflicting types. 740 } 741 742 // A function that has already been declared has been redeclared or defined 743 // with a different type- show appropriate diagnostic 744 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 745 // The user has declared a builtin function with an incompatible 746 // signature. 747 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 748 // The function the user is redeclaring is a library-defined 749 // function like 'malloc' or 'printf'. Warn about the 750 // redeclaration, then pretend that we don't know about this 751 // library built-in. 752 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 753 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 754 << Old << Old->getType(); 755 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 756 Old->setInvalidDecl(); 757 return false; 758 } 759 760 PrevDiag = diag::note_previous_builtin_declaration; 761 } 762 763 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 764 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 765 return true; 766} 767 768/// \brief Completes the merge of two function declarations that are 769/// known to be compatible. 770/// 771/// This routine handles the merging of attributes and other 772/// properties of function declarations form the old declaration to 773/// the new declaration, once we know that New is in fact a 774/// redeclaration of Old. 775/// 776/// \returns false 777bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 778 // Merge the attributes 779 MergeAttributes(New, Old, Context); 780 781 // Merge the storage class. 782 New->setStorageClass(Old->getStorageClass()); 783 784 // FIXME: need to implement inline semantics 785 786 // Merge "pure" flag. 787 if (Old->isPure()) 788 New->setPure(); 789 790 // Merge the "deleted" flag. 791 if (Old->isDeleted()) 792 New->setDeleted(); 793 794 if (getLangOptions().CPlusPlus) 795 return MergeCXXFunctionDecl(New, Old); 796 797 return false; 798} 799 800/// MergeVarDecl - We just parsed a variable 'New' which has the same name 801/// and scope as a previous declaration 'Old'. Figure out how to resolve this 802/// situation, merging decls or emitting diagnostics as appropriate. 803/// 804/// Tentative definition rules (C99 6.9.2p2) are checked by 805/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 806/// definitions here, since the initializer hasn't been attached. 807/// 808bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 809 // Verify the old decl was also a variable. 810 VarDecl *Old = dyn_cast<VarDecl>(OldD); 811 if (!Old) { 812 Diag(New->getLocation(), diag::err_redefinition_different_kind) 813 << New->getDeclName(); 814 Diag(OldD->getLocation(), diag::note_previous_definition); 815 return true; 816 } 817 818 MergeAttributes(New, Old, Context); 819 820 // Merge the types 821 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 822 if (MergedT.isNull()) { 823 Diag(New->getLocation(), diag::err_redefinition_different_type) 824 << New->getDeclName(); 825 Diag(Old->getLocation(), diag::note_previous_definition); 826 return true; 827 } 828 New->setType(MergedT); 829 830 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 831 if (New->getStorageClass() == VarDecl::Static && 832 (Old->getStorageClass() == VarDecl::None || 833 Old->getStorageClass() == VarDecl::Extern)) { 834 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 835 Diag(Old->getLocation(), diag::note_previous_definition); 836 return true; 837 } 838 // C99 6.2.2p4: 839 // For an identifier declared with the storage-class specifier 840 // extern in a scope in which a prior declaration of that 841 // identifier is visible,23) if the prior declaration specifies 842 // internal or external linkage, the linkage of the identifier at 843 // the later declaration is the same as the linkage specified at 844 // the prior declaration. If no prior declaration is visible, or 845 // if the prior declaration specifies no linkage, then the 846 // identifier has external linkage. 847 if (New->hasExternalStorage() && Old->hasLinkage()) 848 /* Okay */; 849 else if (New->getStorageClass() != VarDecl::Static && 850 Old->getStorageClass() == VarDecl::Static) { 851 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 852 Diag(Old->getLocation(), diag::note_previous_definition); 853 return true; 854 } 855 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 856 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl() && 857 // Don't complain about out-of-line definitions of static members. 858 !(Old->getLexicalDeclContext()->isRecord() && 859 !New->getLexicalDeclContext()->isRecord())) { 860 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 861 Diag(Old->getLocation(), diag::note_previous_definition); 862 return true; 863 } 864 865 // Keep a chain of previous declarations. 866 New->setPreviousDeclaration(Old); 867 868 return false; 869} 870 871/// CheckParmsForFunctionDef - Check that the parameters of the given 872/// function are appropriate for the definition of a function. This 873/// takes care of any checks that cannot be performed on the 874/// declaration itself, e.g., that the types of each of the function 875/// parameters are complete. 876bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 877 bool HasInvalidParm = false; 878 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 879 ParmVarDecl *Param = FD->getParamDecl(p); 880 881 // C99 6.7.5.3p4: the parameters in a parameter type list in a 882 // function declarator that is part of a function definition of 883 // that function shall not have incomplete type. 884 if (!Param->isInvalidDecl() && 885 RequireCompleteType(Param->getLocation(), Param->getType(), 886 diag::err_typecheck_decl_incomplete_type)) { 887 Param->setInvalidDecl(); 888 HasInvalidParm = true; 889 } 890 891 // C99 6.9.1p5: If the declarator includes a parameter type list, the 892 // declaration of each parameter shall include an identifier. 893 if (Param->getIdentifier() == 0 && 894 !Param->isImplicit() && 895 !getLangOptions().CPlusPlus) 896 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 897 } 898 899 return HasInvalidParm; 900} 901 902/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 903/// no declarator (e.g. "struct foo;") is parsed. 904Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 905 TagDecl *Tag = 0; 906 if (DS.getTypeSpecType() == DeclSpec::TST_class || 907 DS.getTypeSpecType() == DeclSpec::TST_struct || 908 DS.getTypeSpecType() == DeclSpec::TST_union || 909 DS.getTypeSpecType() == DeclSpec::TST_enum) 910 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 911 912 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 913 if (!Record->getDeclName() && Record->isDefinition() && 914 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 915 if (getLangOptions().CPlusPlus || 916 Record->getDeclContext()->isRecord()) 917 return BuildAnonymousStructOrUnion(S, DS, Record); 918 919 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 920 << DS.getSourceRange(); 921 } 922 923 // Microsoft allows unnamed struct/union fields. Don't complain 924 // about them. 925 // FIXME: Should we support Microsoft's extensions in this area? 926 if (Record->getDeclName() && getLangOptions().Microsoft) 927 return Tag; 928 } 929 930 if (!DS.isMissingDeclaratorOk() && 931 DS.getTypeSpecType() != DeclSpec::TST_error) { 932 // Warn about typedefs of enums without names, since this is an 933 // extension in both Microsoft an GNU. 934 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 935 Tag && isa<EnumDecl>(Tag)) { 936 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 937 << DS.getSourceRange(); 938 return Tag; 939 } 940 941 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 942 << DS.getSourceRange(); 943 return 0; 944 } 945 946 return Tag; 947} 948 949/// InjectAnonymousStructOrUnionMembers - Inject the members of the 950/// anonymous struct or union AnonRecord into the owning context Owner 951/// and scope S. This routine will be invoked just after we realize 952/// that an unnamed union or struct is actually an anonymous union or 953/// struct, e.g., 954/// 955/// @code 956/// union { 957/// int i; 958/// float f; 959/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 960/// // f into the surrounding scope.x 961/// @endcode 962/// 963/// This routine is recursive, injecting the names of nested anonymous 964/// structs/unions into the owning context and scope as well. 965bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 966 RecordDecl *AnonRecord) { 967 bool Invalid = false; 968 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 969 FEnd = AnonRecord->field_end(); 970 F != FEnd; ++F) { 971 if ((*F)->getDeclName()) { 972 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 973 LookupOrdinaryName, true); 974 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 975 // C++ [class.union]p2: 976 // The names of the members of an anonymous union shall be 977 // distinct from the names of any other entity in the 978 // scope in which the anonymous union is declared. 979 unsigned diagKind 980 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 981 : diag::err_anonymous_struct_member_redecl; 982 Diag((*F)->getLocation(), diagKind) 983 << (*F)->getDeclName(); 984 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 985 Invalid = true; 986 } else { 987 // C++ [class.union]p2: 988 // For the purpose of name lookup, after the anonymous union 989 // definition, the members of the anonymous union are 990 // considered to have been defined in the scope in which the 991 // anonymous union is declared. 992 Owner->makeDeclVisibleInContext(*F); 993 S->AddDecl(*F); 994 IdResolver.AddDecl(*F); 995 } 996 } else if (const RecordType *InnerRecordType 997 = (*F)->getType()->getAsRecordType()) { 998 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 999 if (InnerRecord->isAnonymousStructOrUnion()) 1000 Invalid = Invalid || 1001 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1002 } 1003 } 1004 1005 return Invalid; 1006} 1007 1008/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1009/// anonymous structure or union. Anonymous unions are a C++ feature 1010/// (C++ [class.union]) and a GNU C extension; anonymous structures 1011/// are a GNU C and GNU C++ extension. 1012Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1013 RecordDecl *Record) { 1014 DeclContext *Owner = Record->getDeclContext(); 1015 1016 // Diagnose whether this anonymous struct/union is an extension. 1017 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1018 Diag(Record->getLocation(), diag::ext_anonymous_union); 1019 else if (!Record->isUnion()) 1020 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1021 1022 // C and C++ require different kinds of checks for anonymous 1023 // structs/unions. 1024 bool Invalid = false; 1025 if (getLangOptions().CPlusPlus) { 1026 const char* PrevSpec = 0; 1027 // C++ [class.union]p3: 1028 // Anonymous unions declared in a named namespace or in the 1029 // global namespace shall be declared static. 1030 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1031 (isa<TranslationUnitDecl>(Owner) || 1032 (isa<NamespaceDecl>(Owner) && 1033 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1034 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1035 Invalid = true; 1036 1037 // Recover by adding 'static'. 1038 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1039 } 1040 // C++ [class.union]p3: 1041 // A storage class is not allowed in a declaration of an 1042 // anonymous union in a class scope. 1043 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1044 isa<RecordDecl>(Owner)) { 1045 Diag(DS.getStorageClassSpecLoc(), 1046 diag::err_anonymous_union_with_storage_spec); 1047 Invalid = true; 1048 1049 // Recover by removing the storage specifier. 1050 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1051 PrevSpec); 1052 } 1053 1054 // C++ [class.union]p2: 1055 // The member-specification of an anonymous union shall only 1056 // define non-static data members. [Note: nested types and 1057 // functions cannot be declared within an anonymous union. ] 1058 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1059 MemEnd = Record->decls_end(); 1060 Mem != MemEnd; ++Mem) { 1061 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1062 // C++ [class.union]p3: 1063 // An anonymous union shall not have private or protected 1064 // members (clause 11). 1065 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1066 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1067 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1068 Invalid = true; 1069 } 1070 } else if ((*Mem)->isImplicit()) { 1071 // Any implicit members are fine. 1072 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1073 // This is a type that showed up in an 1074 // elaborated-type-specifier inside the anonymous struct or 1075 // union, but which actually declares a type outside of the 1076 // anonymous struct or union. It's okay. 1077 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1078 if (!MemRecord->isAnonymousStructOrUnion() && 1079 MemRecord->getDeclName()) { 1080 // This is a nested type declaration. 1081 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1082 << (int)Record->isUnion(); 1083 Invalid = true; 1084 } 1085 } else { 1086 // We have something that isn't a non-static data 1087 // member. Complain about it. 1088 unsigned DK = diag::err_anonymous_record_bad_member; 1089 if (isa<TypeDecl>(*Mem)) 1090 DK = diag::err_anonymous_record_with_type; 1091 else if (isa<FunctionDecl>(*Mem)) 1092 DK = diag::err_anonymous_record_with_function; 1093 else if (isa<VarDecl>(*Mem)) 1094 DK = diag::err_anonymous_record_with_static; 1095 Diag((*Mem)->getLocation(), DK) 1096 << (int)Record->isUnion(); 1097 Invalid = true; 1098 } 1099 } 1100 } 1101 1102 if (!Record->isUnion() && !Owner->isRecord()) { 1103 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1104 << (int)getLangOptions().CPlusPlus; 1105 Invalid = true; 1106 } 1107 1108 // Create a declaration for this anonymous struct/union. 1109 NamedDecl *Anon = 0; 1110 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1111 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1112 /*IdentifierInfo=*/0, 1113 Context.getTypeDeclType(Record), 1114 /*BitWidth=*/0, /*Mutable=*/false); 1115 Anon->setAccess(AS_public); 1116 if (getLangOptions().CPlusPlus) 1117 FieldCollector->Add(cast<FieldDecl>(Anon)); 1118 } else { 1119 VarDecl::StorageClass SC; 1120 switch (DS.getStorageClassSpec()) { 1121 default: assert(0 && "Unknown storage class!"); 1122 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1123 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1124 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1125 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1126 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1127 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1128 case DeclSpec::SCS_mutable: 1129 // mutable can only appear on non-static class members, so it's always 1130 // an error here 1131 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1132 Invalid = true; 1133 SC = VarDecl::None; 1134 break; 1135 } 1136 1137 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1138 /*IdentifierInfo=*/0, 1139 Context.getTypeDeclType(Record), 1140 SC, DS.getSourceRange().getBegin()); 1141 } 1142 Anon->setImplicit(); 1143 1144 // Add the anonymous struct/union object to the current 1145 // context. We'll be referencing this object when we refer to one of 1146 // its members. 1147 Owner->addDecl(Anon); 1148 1149 // Inject the members of the anonymous struct/union into the owning 1150 // context and into the identifier resolver chain for name lookup 1151 // purposes. 1152 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1153 Invalid = true; 1154 1155 // Mark this as an anonymous struct/union type. Note that we do not 1156 // do this until after we have already checked and injected the 1157 // members of this anonymous struct/union type, because otherwise 1158 // the members could be injected twice: once by DeclContext when it 1159 // builds its lookup table, and once by 1160 // InjectAnonymousStructOrUnionMembers. 1161 Record->setAnonymousStructOrUnion(true); 1162 1163 if (Invalid) 1164 Anon->setInvalidDecl(); 1165 1166 return Anon; 1167} 1168 1169 1170/// GetNameForDeclarator - Determine the full declaration name for the 1171/// given Declarator. 1172DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1173 switch (D.getKind()) { 1174 case Declarator::DK_Abstract: 1175 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1176 return DeclarationName(); 1177 1178 case Declarator::DK_Normal: 1179 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1180 return DeclarationName(D.getIdentifier()); 1181 1182 case Declarator::DK_Constructor: { 1183 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1184 Ty = Context.getCanonicalType(Ty); 1185 return Context.DeclarationNames.getCXXConstructorName(Ty); 1186 } 1187 1188 case Declarator::DK_Destructor: { 1189 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1190 Ty = Context.getCanonicalType(Ty); 1191 return Context.DeclarationNames.getCXXDestructorName(Ty); 1192 } 1193 1194 case Declarator::DK_Conversion: { 1195 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1196 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1197 Ty = Context.getCanonicalType(Ty); 1198 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1199 } 1200 1201 case Declarator::DK_Operator: 1202 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1203 return Context.DeclarationNames.getCXXOperatorName( 1204 D.getOverloadedOperator()); 1205 } 1206 1207 assert(false && "Unknown name kind"); 1208 return DeclarationName(); 1209} 1210 1211/// isNearlyMatchingFunction - Determine whether the C++ functions 1212/// Declaration and Definition are "nearly" matching. This heuristic 1213/// is used to improve diagnostics in the case where an out-of-line 1214/// function definition doesn't match any declaration within 1215/// the class or namespace. 1216static bool isNearlyMatchingFunction(ASTContext &Context, 1217 FunctionDecl *Declaration, 1218 FunctionDecl *Definition) { 1219 if (Declaration->param_size() != Definition->param_size()) 1220 return false; 1221 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1222 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1223 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1224 1225 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1226 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1227 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1228 return false; 1229 } 1230 1231 return true; 1232} 1233 1234Sema::DeclTy * 1235Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1236 bool IsFunctionDefinition) { 1237 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1238 DeclarationName Name = GetNameForDeclarator(D); 1239 1240 // All of these full declarators require an identifier. If it doesn't have 1241 // one, the ParsedFreeStandingDeclSpec action should be used. 1242 if (!Name) { 1243 if (!D.getInvalidType()) // Reject this if we think it is valid. 1244 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1245 diag::err_declarator_need_ident) 1246 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1247 return 0; 1248 } 1249 1250 // The scope passed in may not be a decl scope. Zip up the scope tree until 1251 // we find one that is. 1252 while ((S->getFlags() & Scope::DeclScope) == 0 || 1253 (S->getFlags() & Scope::TemplateParamScope) != 0) 1254 S = S->getParent(); 1255 1256 DeclContext *DC; 1257 NamedDecl *PrevDecl; 1258 NamedDecl *New; 1259 bool InvalidDecl = false; 1260 1261 QualType R = GetTypeForDeclarator(D, S); 1262 if (R.isNull()) { 1263 InvalidDecl = true; 1264 R = Context.IntTy; 1265 } 1266 1267 // See if this is a redefinition of a variable in the same scope. 1268 if (D.getCXXScopeSpec().isInvalid()) { 1269 DC = CurContext; 1270 PrevDecl = 0; 1271 InvalidDecl = true; 1272 } else if (!D.getCXXScopeSpec().isSet()) { 1273 LookupNameKind NameKind = LookupOrdinaryName; 1274 1275 // If the declaration we're planning to build will be a function 1276 // or object with linkage, then look for another declaration with 1277 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1278 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1279 /* Do nothing*/; 1280 else if (R->isFunctionType()) { 1281 if (CurContext->isFunctionOrMethod()) 1282 NameKind = LookupRedeclarationWithLinkage; 1283 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1284 NameKind = LookupRedeclarationWithLinkage; 1285 1286 DC = CurContext; 1287 PrevDecl = LookupName(S, Name, NameKind, true, 1288 D.getDeclSpec().getStorageClassSpec() != 1289 DeclSpec::SCS_static, 1290 D.getIdentifierLoc()); 1291 } else { // Something like "int foo::x;" 1292 DC = computeDeclContext(D.getCXXScopeSpec()); 1293 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1294 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1295 1296 // C++ 7.3.1.2p2: 1297 // Members (including explicit specializations of templates) of a named 1298 // namespace can also be defined outside that namespace by explicit 1299 // qualification of the name being defined, provided that the entity being 1300 // defined was already declared in the namespace and the definition appears 1301 // after the point of declaration in a namespace that encloses the 1302 // declarations namespace. 1303 // 1304 // Note that we only check the context at this point. We don't yet 1305 // have enough information to make sure that PrevDecl is actually 1306 // the declaration we want to match. For example, given: 1307 // 1308 // class X { 1309 // void f(); 1310 // void f(float); 1311 // }; 1312 // 1313 // void X::f(int) { } // ill-formed 1314 // 1315 // In this case, PrevDecl will point to the overload set 1316 // containing the two f's declared in X, but neither of them 1317 // matches. 1318 1319 // First check whether we named the global scope. 1320 if (isa<TranslationUnitDecl>(DC)) { 1321 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1322 << Name << D.getCXXScopeSpec().getRange(); 1323 } else if (!CurContext->Encloses(DC)) { 1324 // The qualifying scope doesn't enclose the original declaration. 1325 // Emit diagnostic based on current scope. 1326 SourceLocation L = D.getIdentifierLoc(); 1327 SourceRange R = D.getCXXScopeSpec().getRange(); 1328 if (isa<FunctionDecl>(CurContext)) 1329 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1330 else 1331 Diag(L, diag::err_invalid_declarator_scope) 1332 << Name << cast<NamedDecl>(DC) << R; 1333 InvalidDecl = true; 1334 } 1335 } 1336 1337 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1338 // Maybe we will complain about the shadowed template parameter. 1339 InvalidDecl = InvalidDecl 1340 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1341 // Just pretend that we didn't see the previous declaration. 1342 PrevDecl = 0; 1343 } 1344 1345 // In C++, the previous declaration we find might be a tag type 1346 // (class or enum). In this case, the new declaration will hide the 1347 // tag type. Note that this does does not apply if we're declaring a 1348 // typedef (C++ [dcl.typedef]p4). 1349 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1350 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1351 PrevDecl = 0; 1352 1353 bool Redeclaration = false; 1354 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1355 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1356 InvalidDecl, Redeclaration); 1357 } else if (R->isFunctionType()) { 1358 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1359 IsFunctionDefinition, InvalidDecl, 1360 Redeclaration); 1361 } else { 1362 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1363 InvalidDecl, Redeclaration); 1364 } 1365 1366 if (New == 0) 1367 return 0; 1368 1369 // If this has an identifier and is not an invalid redeclaration, 1370 // add it to the scope stack. 1371 if (Name && !(Redeclaration && InvalidDecl)) 1372 PushOnScopeChains(New, S); 1373 // If any semantic error occurred, mark the decl as invalid. 1374 if (D.getInvalidType() || InvalidDecl) 1375 New->setInvalidDecl(); 1376 1377 return New; 1378} 1379 1380/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1381/// types into constant array types in certain situations which would otherwise 1382/// be errors (for GCC compatibility). 1383static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1384 ASTContext &Context, 1385 bool &SizeIsNegative) { 1386 // This method tries to turn a variable array into a constant 1387 // array even when the size isn't an ICE. This is necessary 1388 // for compatibility with code that depends on gcc's buggy 1389 // constant expression folding, like struct {char x[(int)(char*)2];} 1390 SizeIsNegative = false; 1391 1392 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1393 QualType Pointee = PTy->getPointeeType(); 1394 QualType FixedType = 1395 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1396 if (FixedType.isNull()) return FixedType; 1397 FixedType = Context.getPointerType(FixedType); 1398 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1399 return FixedType; 1400 } 1401 1402 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1403 if (!VLATy) 1404 return QualType(); 1405 // FIXME: We should probably handle this case 1406 if (VLATy->getElementType()->isVariablyModifiedType()) 1407 return QualType(); 1408 1409 Expr::EvalResult EvalResult; 1410 if (!VLATy->getSizeExpr() || 1411 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1412 !EvalResult.Val.isInt()) 1413 return QualType(); 1414 1415 llvm::APSInt &Res = EvalResult.Val.getInt(); 1416 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1417 return Context.getConstantArrayType(VLATy->getElementType(), 1418 Res, ArrayType::Normal, 0); 1419 1420 SizeIsNegative = true; 1421 return QualType(); 1422} 1423 1424/// \brief Register the given locally-scoped external C declaration so 1425/// that it can be found later for redeclarations 1426void 1427Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1428 Scope *S) { 1429 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1430 "Decl is not a locally-scoped decl!"); 1431 // Note that we have a locally-scoped external with this name. 1432 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1433 1434 if (!PrevDecl) 1435 return; 1436 1437 // If there was a previous declaration of this variable, it may be 1438 // in our identifier chain. Update the identifier chain with the new 1439 // declaration. 1440 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1441 // The previous declaration was found on the identifer resolver 1442 // chain, so remove it from its scope. 1443 while (S && !S->isDeclScope(PrevDecl)) 1444 S = S->getParent(); 1445 1446 if (S) 1447 S->RemoveDecl(PrevDecl); 1448 } 1449} 1450 1451NamedDecl* 1452Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1453 QualType R, Decl* LastDeclarator, 1454 Decl* PrevDecl, bool& InvalidDecl, 1455 bool &Redeclaration) { 1456 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1457 if (D.getCXXScopeSpec().isSet()) { 1458 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1459 << D.getCXXScopeSpec().getRange(); 1460 InvalidDecl = true; 1461 // Pretend we didn't see the scope specifier. 1462 DC = 0; 1463 } 1464 1465 if (getLangOptions().CPlusPlus) { 1466 // Check that there are no default arguments (C++ only). 1467 CheckExtraCXXDefaultArguments(D); 1468 1469 if (D.getDeclSpec().isVirtualSpecified()) 1470 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1471 diag::err_virtual_non_function); 1472 } 1473 1474 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1475 if (!NewTD) return 0; 1476 1477 // Handle attributes prior to checking for duplicates in MergeVarDecl 1478 ProcessDeclAttributes(NewTD, D); 1479 // Merge the decl with the existing one if appropriate. If the decl is 1480 // in an outer scope, it isn't the same thing. 1481 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1482 Redeclaration = true; 1483 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1484 InvalidDecl = true; 1485 } 1486 1487 if (S->getFnParent() == 0) { 1488 QualType T = NewTD->getUnderlyingType(); 1489 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1490 // then it shall have block scope. 1491 if (T->isVariablyModifiedType()) { 1492 bool SizeIsNegative; 1493 QualType FixedTy = 1494 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1495 if (!FixedTy.isNull()) { 1496 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1497 NewTD->setUnderlyingType(FixedTy); 1498 } else { 1499 if (SizeIsNegative) 1500 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1501 else if (T->isVariableArrayType()) 1502 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1503 else 1504 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1505 InvalidDecl = true; 1506 } 1507 } 1508 } 1509 return NewTD; 1510} 1511 1512/// \brief Determines whether the given declaration is an out-of-scope 1513/// previous declaration. 1514/// 1515/// This routine should be invoked when name lookup has found a 1516/// previous declaration (PrevDecl) that is not in the scope where a 1517/// new declaration by the same name is being introduced. If the new 1518/// declaration occurs in a local scope, previous declarations with 1519/// linkage may still be considered previous declarations (C99 1520/// 6.2.2p4-5, C++ [basic.link]p6). 1521/// 1522/// \param PrevDecl the previous declaration found by name 1523/// lookup 1524/// 1525/// \param DC the context in which the new declaration is being 1526/// declared. 1527/// 1528/// \returns true if PrevDecl is an out-of-scope previous declaration 1529/// for a new delcaration with the same name. 1530static bool 1531isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1532 ASTContext &Context) { 1533 if (!PrevDecl) 1534 return 0; 1535 1536 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1537 // case we need to check each of the overloaded functions. 1538 if (!PrevDecl->hasLinkage()) 1539 return false; 1540 1541 if (Context.getLangOptions().CPlusPlus) { 1542 // C++ [basic.link]p6: 1543 // If there is a visible declaration of an entity with linkage 1544 // having the same name and type, ignoring entities declared 1545 // outside the innermost enclosing namespace scope, the block 1546 // scope declaration declares that same entity and receives the 1547 // linkage of the previous declaration. 1548 DeclContext *OuterContext = DC->getLookupContext(); 1549 if (!OuterContext->isFunctionOrMethod()) 1550 // This rule only applies to block-scope declarations. 1551 return false; 1552 else { 1553 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1554 if (PrevOuterContext->isRecord()) 1555 // We found a member function: ignore it. 1556 return false; 1557 else { 1558 // Find the innermost enclosing namespace for the new and 1559 // previous declarations. 1560 while (!OuterContext->isFileContext()) 1561 OuterContext = OuterContext->getParent(); 1562 while (!PrevOuterContext->isFileContext()) 1563 PrevOuterContext = PrevOuterContext->getParent(); 1564 1565 // The previous declaration is in a different namespace, so it 1566 // isn't the same function. 1567 if (OuterContext->getPrimaryContext() != 1568 PrevOuterContext->getPrimaryContext()) 1569 return false; 1570 } 1571 } 1572 } 1573 1574 return true; 1575} 1576 1577NamedDecl* 1578Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1579 QualType R, Decl* LastDeclarator, 1580 NamedDecl* PrevDecl, bool& InvalidDecl, 1581 bool &Redeclaration) { 1582 DeclarationName Name = GetNameForDeclarator(D); 1583 1584 // Check that there are no default arguments (C++ only). 1585 if (getLangOptions().CPlusPlus) 1586 CheckExtraCXXDefaultArguments(D); 1587 1588 if (R.getTypePtr()->isObjCInterfaceType()) { 1589 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object); 1590 InvalidDecl = true; 1591 } 1592 1593 VarDecl *NewVD; 1594 VarDecl::StorageClass SC; 1595 switch (D.getDeclSpec().getStorageClassSpec()) { 1596 default: assert(0 && "Unknown storage class!"); 1597 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1598 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1599 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1600 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1601 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1602 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1603 case DeclSpec::SCS_mutable: 1604 // mutable can only appear on non-static class members, so it's always 1605 // an error here 1606 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1607 InvalidDecl = true; 1608 SC = VarDecl::None; 1609 break; 1610 } 1611 1612 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1613 if (!II) { 1614 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1615 << Name.getAsString(); 1616 return 0; 1617 } 1618 1619 if (D.getDeclSpec().isVirtualSpecified()) 1620 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1621 diag::err_virtual_non_function); 1622 1623 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1624 if (!DC->isRecord() && S->getFnParent() == 0) { 1625 // C99 6.9p2: The storage-class specifiers auto and register shall not 1626 // appear in the declaration specifiers in an external declaration. 1627 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1628 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1629 InvalidDecl = true; 1630 } 1631 } 1632 if (DC->isRecord() && !CurContext->isRecord()) { 1633 // This is an out-of-line definition of a static data member. 1634 if (SC == VarDecl::Static) { 1635 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1636 diag::err_static_out_of_line) 1637 << CodeModificationHint::CreateRemoval( 1638 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1639 } else if (SC == VarDecl::None) 1640 SC = VarDecl::Static; 1641 } 1642 1643 // The variable can not have an abstract class type. 1644 if (RequireNonAbstractType(D.getIdentifierLoc(), R, 1645 diag::err_abstract_type_in_decl, 1646 AbstractVariableType)) 1647 InvalidDecl = true; 1648 1649 // The variable can not 1650 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1651 II, R, SC, 1652 // FIXME: Move to DeclGroup... 1653 D.getDeclSpec().getSourceRange().getBegin()); 1654 NewVD->setThreadSpecified(ThreadSpecified); 1655 NewVD->setNextDeclarator(LastDeclarator); 1656 1657 // Set the lexical context. If the declarator has a C++ scope specifier, the 1658 // lexical context will be different from the semantic context. 1659 NewVD->setLexicalDeclContext(CurContext); 1660 1661 // Handle attributes prior to checking for duplicates in MergeVarDecl 1662 ProcessDeclAttributes(NewVD, D); 1663 1664 // Handle GNU asm-label extension (encoded as an attribute). 1665 if (Expr *E = (Expr*) D.getAsmLabel()) { 1666 // The parser guarantees this is a string. 1667 StringLiteral *SE = cast<StringLiteral>(E); 1668 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1669 SE->getByteLength()))); 1670 } 1671 1672 // Emit an error if an address space was applied to decl with local storage. 1673 // This includes arrays of objects with address space qualifiers, but not 1674 // automatic variables that point to other address spaces. 1675 // ISO/IEC TR 18037 S5.1.2 1676 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1677 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1678 InvalidDecl = true; 1679 } 1680 1681 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1682 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1683 } 1684 1685 bool isIllegalVLA = R->isVariableArrayType() && NewVD->hasGlobalStorage(); 1686 bool isIllegalVM = R->isVariablyModifiedType() && NewVD->hasLinkage(); 1687 if (isIllegalVLA || isIllegalVM) { 1688 bool SizeIsNegative; 1689 QualType FixedTy = 1690 TryToFixInvalidVariablyModifiedType(R, Context, SizeIsNegative); 1691 if (!FixedTy.isNull()) { 1692 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1693 NewVD->setType(FixedTy); 1694 } else if (R->isVariableArrayType()) { 1695 NewVD->setInvalidDecl(); 1696 1697 const VariableArrayType *VAT = Context.getAsVariableArrayType(R); 1698 // FIXME: This won't give the correct result for 1699 // int a[10][n]; 1700 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1701 1702 if (NewVD->isFileVarDecl()) 1703 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1704 << SizeRange; 1705 else if (NewVD->getStorageClass() == VarDecl::Static) 1706 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1707 << SizeRange; 1708 else 1709 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1710 << SizeRange; 1711 } else { 1712 InvalidDecl = true; 1713 1714 if (NewVD->isFileVarDecl()) 1715 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1716 else 1717 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1718 } 1719 } 1720 1721 // If name lookup finds a previous declaration that is not in the 1722 // same scope as the new declaration, this may still be an 1723 // acceptable redeclaration. 1724 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1725 !(NewVD->hasLinkage() && 1726 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1727 PrevDecl = 0; 1728 1729 if (!PrevDecl && NewVD->isExternC(Context)) { 1730 // Since we did not find anything by this name and we're declaring 1731 // an extern "C" variable, look for a non-visible extern "C" 1732 // declaration with the same name. 1733 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1734 = LocallyScopedExternalDecls.find(Name); 1735 if (Pos != LocallyScopedExternalDecls.end()) 1736 PrevDecl = Pos->second; 1737 } 1738 1739 // Merge the decl with the existing one if appropriate. 1740 if (PrevDecl) { 1741 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1742 // The user tried to define a non-static data member 1743 // out-of-line (C++ [dcl.meaning]p1). 1744 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1745 << D.getCXXScopeSpec().getRange(); 1746 NewVD->Destroy(Context); 1747 return 0; 1748 } 1749 1750 Redeclaration = true; 1751 if (MergeVarDecl(NewVD, PrevDecl)) 1752 InvalidDecl = true; 1753 } else if (D.getCXXScopeSpec().isSet()) { 1754 // No previous declaration in the qualifying scope. 1755 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1756 << Name << D.getCXXScopeSpec().getRange(); 1757 InvalidDecl = true; 1758 } 1759 1760 if (!InvalidDecl && R->isVoidType() && !NewVD->hasExternalStorage()) { 1761 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1762 << R; 1763 InvalidDecl = true; 1764 } 1765 1766 1767 // If this is a locally-scoped extern C variable, update the map of 1768 // such variables. 1769 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1770 !InvalidDecl) 1771 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1772 1773 return NewVD; 1774} 1775 1776NamedDecl* 1777Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1778 QualType R, Decl *LastDeclarator, 1779 NamedDecl* PrevDecl, bool IsFunctionDefinition, 1780 bool& InvalidDecl, bool &Redeclaration) { 1781 assert(R.getTypePtr()->isFunctionType()); 1782 1783 DeclarationName Name = GetNameForDeclarator(D); 1784 FunctionDecl::StorageClass SC = FunctionDecl::None; 1785 switch (D.getDeclSpec().getStorageClassSpec()) { 1786 default: assert(0 && "Unknown storage class!"); 1787 case DeclSpec::SCS_auto: 1788 case DeclSpec::SCS_register: 1789 case DeclSpec::SCS_mutable: 1790 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1791 diag::err_typecheck_sclass_func); 1792 InvalidDecl = true; 1793 break; 1794 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1795 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1796 case DeclSpec::SCS_static: { 1797 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1798 // C99 6.7.1p5: 1799 // The declaration of an identifier for a function that has 1800 // block scope shall have no explicit storage-class specifier 1801 // other than extern 1802 // See also (C++ [dcl.stc]p4). 1803 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1804 diag::err_static_block_func); 1805 SC = FunctionDecl::None; 1806 } else 1807 SC = FunctionDecl::Static; 1808 break; 1809 } 1810 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1811 } 1812 1813 bool isInline = D.getDeclSpec().isInlineSpecified(); 1814 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1815 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1816 1817 // Check that the return type is not an abstract class type. 1818 // For record types, this is done by the AbstractClassUsageDiagnoser once 1819 // the class has been completely parsed. 1820 if (!DC->isRecord() && 1821 RequireNonAbstractType(D.getIdentifierLoc(), 1822 R->getAsFunctionType()->getResultType(), 1823 diag::err_abstract_type_in_decl, 1824 AbstractReturnType)) 1825 InvalidDecl = true; 1826 1827 bool isVirtualOkay = false; 1828 FunctionDecl *NewFD; 1829 if (D.getKind() == Declarator::DK_Constructor) { 1830 // This is a C++ constructor declaration. 1831 assert(DC->isRecord() && 1832 "Constructors can only be declared in a member context"); 1833 1834 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1835 1836 // Create the new declaration 1837 NewFD = CXXConstructorDecl::Create(Context, 1838 cast<CXXRecordDecl>(DC), 1839 D.getIdentifierLoc(), Name, R, 1840 isExplicit, isInline, 1841 /*isImplicitlyDeclared=*/false); 1842 1843 if (InvalidDecl) 1844 NewFD->setInvalidDecl(); 1845 } else if (D.getKind() == Declarator::DK_Destructor) { 1846 // This is a C++ destructor declaration. 1847 if (DC->isRecord()) { 1848 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1849 1850 NewFD = CXXDestructorDecl::Create(Context, 1851 cast<CXXRecordDecl>(DC), 1852 D.getIdentifierLoc(), Name, R, 1853 isInline, 1854 /*isImplicitlyDeclared=*/false); 1855 1856 if (InvalidDecl) 1857 NewFD->setInvalidDecl(); 1858 1859 isVirtualOkay = true; 1860 } else { 1861 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1862 1863 // Create a FunctionDecl to satisfy the function definition parsing 1864 // code path. 1865 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1866 Name, R, SC, isInline, 1867 /*hasPrototype=*/true, 1868 // FIXME: Move to DeclGroup... 1869 D.getDeclSpec().getSourceRange().getBegin()); 1870 InvalidDecl = true; 1871 NewFD->setInvalidDecl(); 1872 } 1873 } else if (D.getKind() == Declarator::DK_Conversion) { 1874 if (!DC->isRecord()) { 1875 Diag(D.getIdentifierLoc(), 1876 diag::err_conv_function_not_member); 1877 return 0; 1878 } else { 1879 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1880 1881 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1882 D.getIdentifierLoc(), Name, R, 1883 isInline, isExplicit); 1884 1885 if (InvalidDecl) 1886 NewFD->setInvalidDecl(); 1887 1888 isVirtualOkay = true; 1889 } 1890 } else if (DC->isRecord()) { 1891 // This is a C++ method declaration. 1892 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1893 D.getIdentifierLoc(), Name, R, 1894 (SC == FunctionDecl::Static), isInline); 1895 1896 isVirtualOkay = (SC != FunctionDecl::Static); 1897 } else { 1898 // Determine whether the function was written with a 1899 // prototype. This true when: 1900 // - we're in C++ (where every function has a prototype), 1901 // - there is a prototype in the declarator, or 1902 // - the type R of the function is some kind of typedef or other reference 1903 // to a type name (which eventually refers to a function type). 1904 bool HasPrototype = 1905 getLangOptions().CPlusPlus || 1906 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 1907 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 1908 1909 NewFD = FunctionDecl::Create(Context, DC, 1910 D.getIdentifierLoc(), 1911 Name, R, SC, isInline, HasPrototype, 1912 // FIXME: Move to DeclGroup... 1913 D.getDeclSpec().getSourceRange().getBegin()); 1914 } 1915 NewFD->setNextDeclarator(LastDeclarator); 1916 1917 // Set the lexical context. If the declarator has a C++ 1918 // scope specifier, the lexical context will be different 1919 // from the semantic context. 1920 NewFD->setLexicalDeclContext(CurContext); 1921 1922 // C++ [dcl.fct.spec]p5: 1923 // The virtual specifier shall only be used in declarations of 1924 // nonstatic class member functions that appear within a 1925 // member-specification of a class declaration; see 10.3. 1926 // 1927 // FIXME: Checking the 'virtual' specifier is not sufficient. A 1928 // function is also virtual if it overrides an already virtual 1929 // function. This is important to do here because it's part of the 1930 // declaration. 1931 if (isVirtual && !InvalidDecl) { 1932 if (!isVirtualOkay) { 1933 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1934 diag::err_virtual_non_function); 1935 } else if (!CurContext->isRecord()) { 1936 // 'virtual' was specified outside of the class. 1937 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 1938 << CodeModificationHint::CreateRemoval( 1939 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 1940 } else { 1941 // Okay: Add virtual to the method. 1942 cast<CXXMethodDecl>(NewFD)->setVirtual(); 1943 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 1944 CurClass->setAggregate(false); 1945 CurClass->setPOD(false); 1946 CurClass->setPolymorphic(true); 1947 } 1948 } 1949 1950 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 1951 !CurContext->isRecord()) { 1952 // C++ [class.static]p1: 1953 // A data or function member of a class may be declared static 1954 // in a class definition, in which case it is a static member of 1955 // the class. 1956 1957 // Complain about the 'static' specifier if it's on an out-of-line 1958 // member function definition. 1959 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1960 diag::err_static_out_of_line) 1961 << CodeModificationHint::CreateRemoval( 1962 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1963 } 1964 1965 // Handle GNU asm-label extension (encoded as an attribute). 1966 if (Expr *E = (Expr*) D.getAsmLabel()) { 1967 // The parser guarantees this is a string. 1968 StringLiteral *SE = cast<StringLiteral>(E); 1969 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1970 SE->getByteLength()))); 1971 } 1972 1973 // Copy the parameter declarations from the declarator D to 1974 // the function declaration NewFD, if they are available. 1975 if (D.getNumTypeObjects() > 0) { 1976 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1977 1978 // Create Decl objects for each parameter, adding them to the 1979 // FunctionDecl. 1980 llvm::SmallVector<ParmVarDecl*, 16> Params; 1981 1982 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1983 // function that takes no arguments, not a function that takes a 1984 // single void argument. 1985 // We let through "const void" here because Sema::GetTypeForDeclarator 1986 // already checks for that case. 1987 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1988 FTI.ArgInfo[0].Param && 1989 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1990 // empty arg list, don't push any params. 1991 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1992 1993 // In C++, the empty parameter-type-list must be spelled "void"; a 1994 // typedef of void is not permitted. 1995 if (getLangOptions().CPlusPlus && 1996 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1997 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1998 } 1999 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2000 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2001 ParmVarDecl *PVD = (ParmVarDecl *)FTI.ArgInfo[i].Param; 2002 Params.push_back(PVD); 2003 } 2004 } 2005 2006 NewFD->setParams(Context, &Params[0], Params.size()); 2007 } else if (R->getAsTypedefType()) { 2008 // When we're declaring a function with a typedef, as in the 2009 // following example, we'll need to synthesize (unnamed) 2010 // parameters for use in the declaration. 2011 // 2012 // @code 2013 // typedef void fn(int); 2014 // fn f; 2015 // @endcode 2016 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2017 if (!FT) { 2018 // This is a typedef of a function with no prototype, so we 2019 // don't need to do anything. 2020 } else if ((FT->getNumArgs() == 0) || 2021 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2022 FT->getArgType(0)->isVoidType())) { 2023 // This is a zero-argument function. We don't need to do anything. 2024 } else { 2025 // Synthesize a parameter for each argument type. 2026 llvm::SmallVector<ParmVarDecl*, 16> Params; 2027 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2028 ArgType != FT->arg_type_end(); ++ArgType) { 2029 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2030 SourceLocation(), 0, 2031 *ArgType, VarDecl::None, 2032 0); 2033 Param->setImplicit(); 2034 Params.push_back(Param); 2035 } 2036 2037 NewFD->setParams(Context, &Params[0], Params.size()); 2038 } 2039 } 2040 2041 // If name lookup finds a previous declaration that is not in the 2042 // same scope as the new declaration, this may still be an 2043 // acceptable redeclaration. 2044 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2045 !(NewFD->hasLinkage() && 2046 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2047 PrevDecl = 0; 2048 2049 // Perform semantic checking on the function declaration. 2050 bool OverloadableAttrRequired = false; // FIXME: HACK! 2051 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2052 /*FIXME:*/OverloadableAttrRequired)) 2053 InvalidDecl = true; 2054 2055 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2056 // An out-of-line member function declaration must also be a 2057 // definition (C++ [dcl.meaning]p1). 2058 if (!IsFunctionDefinition) { 2059 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2060 << D.getCXXScopeSpec().getRange(); 2061 InvalidDecl = true; 2062 } else if (!Redeclaration) { 2063 // The user tried to provide an out-of-line definition for a 2064 // function that is a member of a class or namespace, but there 2065 // was no such member function declared (C++ [class.mfct]p2, 2066 // C++ [namespace.memdef]p2). For example: 2067 // 2068 // class X { 2069 // void f() const; 2070 // }; 2071 // 2072 // void X::f() { } // ill-formed 2073 // 2074 // Complain about this problem, and attempt to suggest close 2075 // matches (e.g., those that differ only in cv-qualifiers and 2076 // whether the parameter types are references). 2077 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2078 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2079 InvalidDecl = true; 2080 2081 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2082 true); 2083 assert(!Prev.isAmbiguous() && 2084 "Cannot have an ambiguity in previous-declaration lookup"); 2085 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2086 Func != FuncEnd; ++Func) { 2087 if (isa<FunctionDecl>(*Func) && 2088 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2089 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2090 } 2091 2092 PrevDecl = 0; 2093 } 2094 } 2095 2096 // Handle attributes. We need to have merged decls when handling attributes 2097 // (for example to check for conflicts, etc). 2098 // FIXME: This needs to happen before we merge declarations. Then, 2099 // let attribute merging cope with attribute conflicts. 2100 ProcessDeclAttributes(NewFD, D); 2101 AddKnownFunctionAttributes(NewFD); 2102 2103 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2104 // If a function name is overloadable in C, then every function 2105 // with that name must be marked "overloadable". 2106 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2107 << Redeclaration << NewFD; 2108 if (PrevDecl) 2109 Diag(PrevDecl->getLocation(), 2110 diag::note_attribute_overloadable_prev_overload); 2111 NewFD->addAttr(::new (Context) OverloadableAttr()); 2112 } 2113 2114 // If this is a locally-scoped extern C function, update the 2115 // map of such names. 2116 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2117 && !InvalidDecl) 2118 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2119 2120 return NewFD; 2121} 2122 2123/// \brief Perform semantic checking of a new function declaration. 2124/// 2125/// Performs semantic analysis of the new function declaration 2126/// NewFD. This routine performs all semantic checking that does not 2127/// require the actual declarator involved in the declaration, and is 2128/// used both for the declaration of functions as they are parsed 2129/// (called via ActOnDeclarator) and for the declaration of functions 2130/// that have been instantiated via C++ template instantiation (called 2131/// via InstantiateDecl). 2132/// 2133/// \returns true if there was an error, false otherwise. 2134bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2135 bool &Redeclaration, 2136 bool &OverloadableAttrRequired) { 2137 bool InvalidDecl = false; 2138 2139 // Semantic checking for this function declaration (in isolation). 2140 if (getLangOptions().CPlusPlus) { 2141 // C++-specific checks. 2142 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2143 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2144 else if (isa<CXXDestructorDecl>(NewFD)) { 2145 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2146 Record->setUserDeclaredDestructor(true); 2147 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2148 // user-defined destructor. 2149 Record->setPOD(false); 2150 } else if (CXXConversionDecl *Conversion 2151 = dyn_cast<CXXConversionDecl>(NewFD)) 2152 ActOnConversionDeclarator(Conversion); 2153 2154 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2155 if (NewFD->isOverloadedOperator() && 2156 CheckOverloadedOperatorDeclaration(NewFD)) 2157 InvalidDecl = true; 2158 } 2159 2160 // Check for a previous declaration of this name. 2161 if (!PrevDecl && NewFD->isExternC(Context)) { 2162 // Since we did not find anything by this name and we're declaring 2163 // an extern "C" function, look for a non-visible extern "C" 2164 // declaration with the same name. 2165 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2166 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2167 if (Pos != LocallyScopedExternalDecls.end()) 2168 PrevDecl = Pos->second; 2169 } 2170 2171 // Merge or overload the declaration with an existing declaration of 2172 // the same name, if appropriate. 2173 if (PrevDecl) { 2174 // Determine whether NewFD is an overload of PrevDecl or 2175 // a declaration that requires merging. If it's an overload, 2176 // there's no more work to do here; we'll just add the new 2177 // function to the scope. 2178 OverloadedFunctionDecl::function_iterator MatchedDecl; 2179 2180 if (!getLangOptions().CPlusPlus && 2181 AllowOverloadingOfFunction(PrevDecl, Context)) { 2182 OverloadableAttrRequired = true; 2183 2184 // Functions marked "overloadable" must have a prototype (that 2185 // we can't get through declaration merging). 2186 if (!NewFD->getType()->getAsFunctionProtoType()) { 2187 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2188 << NewFD; 2189 InvalidDecl = true; 2190 Redeclaration = true; 2191 2192 // Turn this into a variadic function with no parameters. 2193 QualType R = Context.getFunctionType( 2194 NewFD->getType()->getAsFunctionType()->getResultType(), 2195 0, 0, true, 0); 2196 NewFD->setType(R); 2197 } 2198 } 2199 2200 if (PrevDecl && 2201 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2202 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2203 Redeclaration = true; 2204 Decl *OldDecl = PrevDecl; 2205 2206 // If PrevDecl was an overloaded function, extract the 2207 // FunctionDecl that matched. 2208 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2209 OldDecl = *MatchedDecl; 2210 2211 // NewFD and OldDecl represent declarations that need to be 2212 // merged. 2213 if (MergeFunctionDecl(NewFD, OldDecl)) 2214 InvalidDecl = true; 2215 2216 if (!InvalidDecl) 2217 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2218 } 2219 } 2220 2221 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2222 // In C++, check default arguments now that we have merged decls. Unless 2223 // the lexical context is the class, because in this case this is done 2224 // during delayed parsing anyway. 2225 CheckCXXDefaultArguments(NewFD); 2226 } 2227 2228 return InvalidDecl || NewFD->isInvalidDecl(); 2229} 2230 2231bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2232 // FIXME: Need strict checking. In C89, we need to check for 2233 // any assignment, increment, decrement, function-calls, or 2234 // commas outside of a sizeof. In C99, it's the same list, 2235 // except that the aforementioned are allowed in unevaluated 2236 // expressions. Everything else falls under the 2237 // "may accept other forms of constant expressions" exception. 2238 // (We never end up here for C++, so the constant expression 2239 // rules there don't matter.) 2240 if (Init->isConstantInitializer(Context)) 2241 return false; 2242 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2243 << Init->getSourceRange(); 2244 return true; 2245} 2246 2247void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2248 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2249} 2250 2251/// AddInitializerToDecl - Adds the initializer Init to the 2252/// declaration dcl. If DirectInit is true, this is C++ direct 2253/// initialization rather than copy initialization. 2254void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2255 Decl *RealDecl = static_cast<Decl *>(dcl); 2256 // If there is no declaration, there was an error parsing it. Just ignore 2257 // the initializer. 2258 if (RealDecl == 0) 2259 return; 2260 2261 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2262 // With declarators parsed the way they are, the parser cannot 2263 // distinguish between a normal initializer and a pure-specifier. 2264 // Thus this grotesque test. 2265 IntegerLiteral *IL; 2266 Expr *Init = static_cast<Expr *>(init.get()); 2267 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2268 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2269 if (Method->isVirtual()) { 2270 Method->setPure(); 2271 2272 // A class is abstract if at least one function is pure virtual. 2273 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2274 } else { 2275 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2276 << Method->getDeclName() << Init->getSourceRange(); 2277 Method->setInvalidDecl(); 2278 } 2279 } else { 2280 Diag(Method->getLocation(), diag::err_member_function_initialization) 2281 << Method->getDeclName() << Init->getSourceRange(); 2282 Method->setInvalidDecl(); 2283 } 2284 return; 2285 } 2286 2287 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2288 if (!VDecl) { 2289 if (getLangOptions().CPlusPlus && 2290 RealDecl->getLexicalDeclContext()->isRecord() && 2291 isa<NamedDecl>(RealDecl)) 2292 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2293 << cast<NamedDecl>(RealDecl)->getDeclName(); 2294 else 2295 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2296 RealDecl->setInvalidDecl(); 2297 return; 2298 } 2299 2300 const VarDecl *Def = 0; 2301 if (VDecl->getDefinition(Def)) { 2302 Diag(VDecl->getLocation(), diag::err_redefinition) 2303 << VDecl->getDeclName(); 2304 Diag(Def->getLocation(), diag::note_previous_definition); 2305 VDecl->setInvalidDecl(); 2306 return; 2307 } 2308 2309 // Take ownership of the expression, now that we're sure we have somewhere 2310 // to put it. 2311 Expr *Init = static_cast<Expr *>(init.release()); 2312 assert(Init && "missing initializer"); 2313 2314 // Get the decls type and save a reference for later, since 2315 // CheckInitializerTypes may change it. 2316 QualType DclT = VDecl->getType(), SavT = DclT; 2317 if (VDecl->isBlockVarDecl()) { 2318 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2319 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2320 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2321 VDecl->setInvalidDecl(); 2322 } else if (!VDecl->isInvalidDecl()) { 2323 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2324 VDecl->getDeclName(), DirectInit)) 2325 VDecl->setInvalidDecl(); 2326 2327 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2328 // Don't check invalid declarations to avoid emitting useless diagnostics. 2329 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2330 if (SC == VarDecl::Static) // C99 6.7.8p4. 2331 CheckForConstantInitializer(Init, DclT); 2332 } 2333 } 2334 } else if (VDecl->isStaticDataMember() && 2335 VDecl->getLexicalDeclContext()->isRecord()) { 2336 // This is an in-class initialization for a static data member, e.g., 2337 // 2338 // struct S { 2339 // static const int value = 17; 2340 // }; 2341 2342 // Attach the initializer 2343 VDecl->setInit(Init); 2344 2345 // C++ [class.mem]p4: 2346 // A member-declarator can contain a constant-initializer only 2347 // if it declares a static member (9.4) of const integral or 2348 // const enumeration type, see 9.4.2. 2349 QualType T = VDecl->getType(); 2350 if (!T->isDependentType() && 2351 (!Context.getCanonicalType(T).isConstQualified() || 2352 !T->isIntegralType())) { 2353 Diag(VDecl->getLocation(), diag::err_member_initialization) 2354 << VDecl->getDeclName() << Init->getSourceRange(); 2355 VDecl->setInvalidDecl(); 2356 } else { 2357 // C++ [class.static.data]p4: 2358 // If a static data member is of const integral or const 2359 // enumeration type, its declaration in the class definition 2360 // can specify a constant-initializer which shall be an 2361 // integral constant expression (5.19). 2362 if (!Init->isTypeDependent() && 2363 !Init->getType()->isIntegralType()) { 2364 // We have a non-dependent, non-integral or enumeration type. 2365 Diag(Init->getSourceRange().getBegin(), 2366 diag::err_in_class_initializer_non_integral_type) 2367 << Init->getType() << Init->getSourceRange(); 2368 VDecl->setInvalidDecl(); 2369 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2370 // Check whether the expression is a constant expression. 2371 llvm::APSInt Value; 2372 SourceLocation Loc; 2373 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2374 Diag(Loc, diag::err_in_class_initializer_non_constant) 2375 << Init->getSourceRange(); 2376 VDecl->setInvalidDecl(); 2377 } 2378 } 2379 } 2380 } else if (VDecl->isFileVarDecl()) { 2381 if (VDecl->getStorageClass() == VarDecl::Extern) 2382 Diag(VDecl->getLocation(), diag::warn_extern_init); 2383 if (!VDecl->isInvalidDecl()) 2384 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2385 VDecl->getDeclName(), DirectInit)) 2386 VDecl->setInvalidDecl(); 2387 2388 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2389 // Don't check invalid declarations to avoid emitting useless diagnostics. 2390 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2391 // C99 6.7.8p4. All file scoped initializers need to be constant. 2392 CheckForConstantInitializer(Init, DclT); 2393 } 2394 } 2395 // If the type changed, it means we had an incomplete type that was 2396 // completed by the initializer. For example: 2397 // int ary[] = { 1, 3, 5 }; 2398 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2399 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2400 VDecl->setType(DclT); 2401 Init->setType(DclT); 2402 } 2403 2404 // Attach the initializer to the decl. 2405 VDecl->setInit(Init); 2406 return; 2407} 2408 2409void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2410 Decl *RealDecl = static_cast<Decl *>(dcl); 2411 2412 // If there is no declaration, there was an error parsing it. Just ignore it. 2413 if (RealDecl == 0) 2414 return; 2415 2416 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2417 QualType Type = Var->getType(); 2418 // C++ [dcl.init.ref]p3: 2419 // The initializer can be omitted for a reference only in a 2420 // parameter declaration (8.3.5), in the declaration of a 2421 // function return type, in the declaration of a class member 2422 // within its class declaration (9.2), and where the extern 2423 // specifier is explicitly used. 2424 if (Type->isReferenceType() && 2425 Var->getStorageClass() != VarDecl::Extern && 2426 Var->getStorageClass() != VarDecl::PrivateExtern) { 2427 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2428 << Var->getDeclName() 2429 << SourceRange(Var->getLocation(), Var->getLocation()); 2430 Var->setInvalidDecl(); 2431 return; 2432 } 2433 2434 // C++ [dcl.init]p9: 2435 // 2436 // If no initializer is specified for an object, and the object 2437 // is of (possibly cv-qualified) non-POD class type (or array 2438 // thereof), the object shall be default-initialized; if the 2439 // object is of const-qualified type, the underlying class type 2440 // shall have a user-declared default constructor. 2441 if (getLangOptions().CPlusPlus) { 2442 QualType InitType = Type; 2443 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2444 InitType = Array->getElementType(); 2445 if (Var->getStorageClass() != VarDecl::Extern && 2446 Var->getStorageClass() != VarDecl::PrivateExtern && 2447 InitType->isRecordType()) { 2448 const CXXConstructorDecl *Constructor = 0; 2449 if (!RequireCompleteType(Var->getLocation(), InitType, 2450 diag::err_invalid_incomplete_type_use)) 2451 Constructor 2452 = PerformInitializationByConstructor(InitType, 0, 0, 2453 Var->getLocation(), 2454 SourceRange(Var->getLocation(), 2455 Var->getLocation()), 2456 Var->getDeclName(), 2457 IK_Default); 2458 if (!Constructor) 2459 Var->setInvalidDecl(); 2460 } 2461 } 2462 2463#if 0 2464 // FIXME: Temporarily disabled because we are not properly parsing 2465 // linkage specifications on declarations, e.g., 2466 // 2467 // extern "C" const CGPoint CGPointerZero; 2468 // 2469 // C++ [dcl.init]p9: 2470 // 2471 // If no initializer is specified for an object, and the 2472 // object is of (possibly cv-qualified) non-POD class type (or 2473 // array thereof), the object shall be default-initialized; if 2474 // the object is of const-qualified type, the underlying class 2475 // type shall have a user-declared default 2476 // constructor. Otherwise, if no initializer is specified for 2477 // an object, the object and its subobjects, if any, have an 2478 // indeterminate initial value; if the object or any of its 2479 // subobjects are of const-qualified type, the program is 2480 // ill-formed. 2481 // 2482 // This isn't technically an error in C, so we don't diagnose it. 2483 // 2484 // FIXME: Actually perform the POD/user-defined default 2485 // constructor check. 2486 if (getLangOptions().CPlusPlus && 2487 Context.getCanonicalType(Type).isConstQualified() && 2488 Var->getStorageClass() != VarDecl::Extern) 2489 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2490 << Var->getName() 2491 << SourceRange(Var->getLocation(), Var->getLocation()); 2492#endif 2493 } 2494} 2495 2496/// The declarators are chained together backwards, reverse the list. 2497Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2498 // Often we have single declarators, handle them quickly. 2499 Decl *Group = static_cast<Decl*>(group); 2500 if (Group == 0) 2501 return 0; 2502 2503 Decl *NewGroup = 0; 2504 if (Group->getNextDeclarator() == 0) 2505 NewGroup = Group; 2506 else { // reverse the list. 2507 while (Group) { 2508 Decl *Next = Group->getNextDeclarator(); 2509 Group->setNextDeclarator(NewGroup); 2510 NewGroup = Group; 2511 Group = Next; 2512 } 2513 } 2514 // Perform semantic analysis that depends on having fully processed both 2515 // the declarator and initializer. 2516 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2517 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2518 if (!IDecl) 2519 continue; 2520 QualType T = IDecl->getType(); 2521 2522 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2523 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2524 if (IDecl->isBlockVarDecl() && 2525 IDecl->getStorageClass() != VarDecl::Extern) { 2526 if (!IDecl->isInvalidDecl() && 2527 RequireCompleteType(IDecl->getLocation(), T, 2528 diag::err_typecheck_decl_incomplete_type)) 2529 IDecl->setInvalidDecl(); 2530 } 2531 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2532 // object that has file scope without an initializer, and without a 2533 // storage-class specifier or with the storage-class specifier "static", 2534 // constitutes a tentative definition. Note: A tentative definition with 2535 // external linkage is valid (C99 6.2.2p5). 2536 if (IDecl->isTentativeDefinition(Context)) { 2537 QualType CheckType = T; 2538 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2539 2540 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2541 if (ArrayT) { 2542 CheckType = ArrayT->getElementType(); 2543 DiagID = diag::err_illegal_decl_array_incomplete_type; 2544 } 2545 2546 if (IDecl->isInvalidDecl()) { 2547 // Do nothing with invalid declarations 2548 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2549 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2550 // C99 6.9.2p3: If the declaration of an identifier for an object is 2551 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2552 // declared type shall not be an incomplete type. 2553 IDecl->setInvalidDecl(); 2554 } 2555 } 2556 } 2557 return NewGroup; 2558} 2559 2560/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2561/// to introduce parameters into function prototype scope. 2562Sema::DeclTy * 2563Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2564 const DeclSpec &DS = D.getDeclSpec(); 2565 2566 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2567 VarDecl::StorageClass StorageClass = VarDecl::None; 2568 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2569 StorageClass = VarDecl::Register; 2570 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2571 Diag(DS.getStorageClassSpecLoc(), 2572 diag::err_invalid_storage_class_in_func_decl); 2573 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2574 } 2575 if (DS.isThreadSpecified()) { 2576 Diag(DS.getThreadSpecLoc(), 2577 diag::err_invalid_storage_class_in_func_decl); 2578 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2579 } 2580 2581 // Check that there are no default arguments inside the type of this 2582 // parameter (C++ only). 2583 if (getLangOptions().CPlusPlus) 2584 CheckExtraCXXDefaultArguments(D); 2585 2586 // In this context, we *do not* check D.getInvalidType(). If the declarator 2587 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2588 // though it will not reflect the user specified type. 2589 QualType parmDeclType = GetTypeForDeclarator(D, S); 2590 2591 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2592 2593 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2594 // Can this happen for params? We already checked that they don't conflict 2595 // among each other. Here they can only shadow globals, which is ok. 2596 IdentifierInfo *II = D.getIdentifier(); 2597 if (II) { 2598 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2599 if (PrevDecl->isTemplateParameter()) { 2600 // Maybe we will complain about the shadowed template parameter. 2601 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2602 // Just pretend that we didn't see the previous declaration. 2603 PrevDecl = 0; 2604 } else if (S->isDeclScope(PrevDecl)) { 2605 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2606 2607 // Recover by removing the name 2608 II = 0; 2609 D.SetIdentifier(0, D.getIdentifierLoc()); 2610 } 2611 } 2612 } 2613 2614 // Parameters can not be abstract class types. 2615 // For record types, this is done by the AbstractClassUsageDiagnoser once 2616 // the class has been completely parsed. 2617 if (!CurContext->isRecord() && 2618 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2619 diag::err_abstract_type_in_decl, 2620 AbstractParamType)) 2621 D.setInvalidType(true); 2622 2623 QualType T = adjustParameterType(parmDeclType); 2624 2625 ParmVarDecl *New; 2626 if (T == parmDeclType) // parameter type did not need adjustment 2627 New = ParmVarDecl::Create(Context, CurContext, 2628 D.getIdentifierLoc(), II, 2629 parmDeclType, StorageClass, 2630 0); 2631 else // keep track of both the adjusted and unadjusted types 2632 New = OriginalParmVarDecl::Create(Context, CurContext, 2633 D.getIdentifierLoc(), II, T, 2634 parmDeclType, StorageClass, 0); 2635 2636 if (D.getInvalidType()) 2637 New->setInvalidDecl(); 2638 2639 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2640 if (D.getCXXScopeSpec().isSet()) { 2641 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2642 << D.getCXXScopeSpec().getRange(); 2643 New->setInvalidDecl(); 2644 } 2645 // Parameter declarators cannot be interface types. All ObjC objects are 2646 // passed by reference. 2647 if (T->isObjCInterfaceType()) { 2648 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2649 << "passed"; 2650 New->setInvalidDecl(); 2651 } 2652 2653 // Add the parameter declaration into this scope. 2654 S->AddDecl(New); 2655 if (II) 2656 IdResolver.AddDecl(New); 2657 2658 ProcessDeclAttributes(New, D); 2659 return New; 2660 2661} 2662 2663void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2664 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2665 "Not a function declarator!"); 2666 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2667 2668 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2669 // for a K&R function. 2670 if (!FTI.hasPrototype) { 2671 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2672 if (FTI.ArgInfo[i].Param == 0) { 2673 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2674 << FTI.ArgInfo[i].Ident; 2675 // Implicitly declare the argument as type 'int' for lack of a better 2676 // type. 2677 DeclSpec DS; 2678 const char* PrevSpec; // unused 2679 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2680 PrevSpec); 2681 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2682 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2683 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2684 } 2685 } 2686 } 2687} 2688 2689Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2690 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2691 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2692 "Not a function declarator!"); 2693 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2694 2695 if (FTI.hasPrototype) { 2696 // FIXME: Diagnose arguments without names in C. 2697 } 2698 2699 Scope *ParentScope = FnBodyScope->getParent(); 2700 2701 return ActOnStartOfFunctionDef(FnBodyScope, 2702 ActOnDeclarator(ParentScope, D, 0, 2703 /*IsFunctionDefinition=*/true)); 2704} 2705 2706Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2707 Decl *decl = static_cast<Decl*>(D); 2708 FunctionDecl *FD = cast<FunctionDecl>(decl); 2709 2710 // See if this is a redefinition. 2711 const FunctionDecl *Definition; 2712 if (FD->getBody(Definition)) { 2713 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2714 Diag(Definition->getLocation(), diag::note_previous_definition); 2715 } 2716 2717 // Builtin functions cannot be defined. 2718 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2719 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2720 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2721 FD->setInvalidDecl(); 2722 } 2723 } 2724 2725 // The return type of a function definition must be complete 2726 // (C99 6.9.1p3) 2727 if (FD->getResultType()->isIncompleteType() && 2728 !FD->getResultType()->isVoidType()) { 2729 Diag(FD->getLocation(), diag::err_func_def_incomplete_result) << FD; 2730 FD->setInvalidDecl(); 2731 } 2732 2733 PushDeclContext(FnBodyScope, FD); 2734 2735 // Check the validity of our function parameters 2736 CheckParmsForFunctionDef(FD); 2737 2738 // Introduce our parameters into the function scope 2739 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2740 ParmVarDecl *Param = FD->getParamDecl(p); 2741 Param->setOwningFunction(FD); 2742 2743 // If this has an identifier, add it to the scope stack. 2744 if (Param->getIdentifier()) 2745 PushOnScopeChains(Param, FnBodyScope); 2746 } 2747 2748 // Checking attributes of current function definition 2749 // dllimport attribute. 2750 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2751 // dllimport attribute cannot be applied to definition. 2752 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2753 Diag(FD->getLocation(), 2754 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2755 << "dllimport"; 2756 FD->setInvalidDecl(); 2757 return FD; 2758 } else { 2759 // If a symbol previously declared dllimport is later defined, the 2760 // attribute is ignored in subsequent references, and a warning is 2761 // emitted. 2762 Diag(FD->getLocation(), 2763 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2764 << FD->getNameAsCString() << "dllimport"; 2765 } 2766 } 2767 return FD; 2768} 2769 2770static bool StatementCreatesScope(Stmt* S) { 2771 bool result = false; 2772 if (DeclStmt* DS = dyn_cast<DeclStmt>(S)) { 2773 for (DeclStmt::decl_iterator i = DS->decl_begin(); 2774 i != DS->decl_end(); ++i) { 2775 if (VarDecl* D = dyn_cast<VarDecl>(*i)) { 2776 result |= D->getType()->isVariablyModifiedType(); 2777 result |= !!D->getAttr<CleanupAttr>(); 2778 } else if (TypedefDecl* D = dyn_cast<TypedefDecl>(*i)) { 2779 result |= D->getUnderlyingType()->isVariablyModifiedType(); 2780 } 2781 } 2782 } 2783 2784 return result; 2785} 2786 2787void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2788 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2789 std::vector<void*>& ScopeStack, 2790 Stmt* CurStmt, 2791 Stmt* ParentCompoundStmt) { 2792 for (Stmt::child_iterator i = CurStmt->child_begin(); 2793 i != CurStmt->child_end(); ++i) { 2794 if (!*i) continue; 2795 if (StatementCreatesScope(*i)) { 2796 ScopeStack.push_back(*i); 2797 PopScopeMap[*i] = ParentCompoundStmt; 2798 } else if (isa<LabelStmt>(CurStmt)) { 2799 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2800 } 2801 if (isa<DeclStmt>(*i)) continue; 2802 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2803 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2804 *i, CurCompound); 2805 } 2806 2807 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2808 ScopeStack.pop_back(); 2809 } 2810} 2811 2812void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2813 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2814 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2815 std::vector<void*>& ScopeStack, 2816 Stmt* CurStmt) { 2817 for (Stmt::child_iterator i = CurStmt->child_begin(); 2818 i != CurStmt->child_end(); ++i) { 2819 if (!*i) continue; 2820 if (StatementCreatesScope(*i)) { 2821 ScopeStack.push_back(*i); 2822 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2823 void* LScope = LabelScopeMap[GS->getLabel()]; 2824 if (LScope) { 2825 bool foundScopeInStack = false; 2826 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2827 if (LScope == ScopeStack[i-1]) { 2828 foundScopeInStack = true; 2829 break; 2830 } 2831 } 2832 if (!foundScopeInStack) { 2833 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2834 } 2835 } 2836 } 2837 if (isa<DeclStmt>(*i)) continue; 2838 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2839 ScopeStack, *i); 2840 } 2841 2842 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2843 ScopeStack.pop_back(); 2844 } 2845} 2846 2847Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2848 Decl *dcl = static_cast<Decl *>(D); 2849 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2850 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2851 FD->setBody(cast<CompoundStmt>(Body)); 2852 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2853 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2854 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2855 MD->setBody(cast<CompoundStmt>(Body)); 2856 } else { 2857 Body->Destroy(Context); 2858 return 0; 2859 } 2860 PopDeclContext(); 2861 // Verify and clean out per-function state. 2862 2863 bool HaveLabels = !LabelMap.empty(); 2864 // Check goto/label use. 2865 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2866 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2867 // Verify that we have no forward references left. If so, there was a goto 2868 // or address of a label taken, but no definition of it. Label fwd 2869 // definitions are indicated with a null substmt. 2870 if (I->second->getSubStmt() == 0) { 2871 LabelStmt *L = I->second; 2872 // Emit error. 2873 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2874 2875 // At this point, we have gotos that use the bogus label. Stitch it into 2876 // the function body so that they aren't leaked and that the AST is well 2877 // formed. 2878 if (Body) { 2879#if 0 2880 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2881 // and the AST is malformed anyway. We should just blow away 'L'. 2882 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2883 cast<CompoundStmt>(Body)->push_back(L); 2884#else 2885 L->Destroy(Context); 2886#endif 2887 } else { 2888 // The whole function wasn't parsed correctly, just delete this. 2889 L->Destroy(Context); 2890 } 2891 } 2892 } 2893 LabelMap.clear(); 2894 2895 if (!Body) return D; 2896 2897 if (HaveLabels) { 2898 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2899 llvm::DenseMap<void*, Stmt*> PopScopeMap; 2900 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 2901 std::vector<void*> ScopeStack; 2902 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 2903 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 2904 } 2905 2906 return D; 2907} 2908 2909/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2910/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2911NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2912 IdentifierInfo &II, Scope *S) { 2913 // Before we produce a declaration for an implicitly defined 2914 // function, see whether there was a locally-scoped declaration of 2915 // this name as a function or variable. If so, use that 2916 // (non-visible) declaration, and complain about it. 2917 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2918 = LocallyScopedExternalDecls.find(&II); 2919 if (Pos != LocallyScopedExternalDecls.end()) { 2920 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 2921 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 2922 return Pos->second; 2923 } 2924 2925 // Extension in C99. Legal in C90, but warn about it. 2926 if (getLangOptions().C99) 2927 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2928 else 2929 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2930 2931 // FIXME: handle stuff like: 2932 // void foo() { extern float X(); } 2933 // void bar() { X(); } <-- implicit decl for X in another scope. 2934 2935 // Set a Declarator for the implicit definition: int foo(); 2936 const char *Dummy; 2937 DeclSpec DS; 2938 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2939 Error = Error; // Silence warning. 2940 assert(!Error && "Error setting up implicit decl!"); 2941 Declarator D(DS, Declarator::BlockContext); 2942 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 2943 0, 0, 0, Loc, D), 2944 SourceLocation()); 2945 D.SetIdentifier(&II, Loc); 2946 2947 // Insert this function into translation-unit scope. 2948 2949 DeclContext *PrevDC = CurContext; 2950 CurContext = Context.getTranslationUnitDecl(); 2951 2952 FunctionDecl *FD = 2953 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2954 FD->setImplicit(); 2955 2956 CurContext = PrevDC; 2957 2958 AddKnownFunctionAttributes(FD); 2959 2960 return FD; 2961} 2962 2963/// \brief Adds any function attributes that we know a priori based on 2964/// the declaration of this function. 2965/// 2966/// These attributes can apply both to implicitly-declared builtins 2967/// (like __builtin___printf_chk) or to library-declared functions 2968/// like NSLog or printf. 2969void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2970 if (FD->isInvalidDecl()) 2971 return; 2972 2973 // If this is a built-in function, map its builtin attributes to 2974 // actual attributes. 2975 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2976 // Handle printf-formatting attributes. 2977 unsigned FormatIdx; 2978 bool HasVAListArg; 2979 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2980 if (!FD->getAttr<FormatAttr>()) 2981 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 2982 FormatIdx + 2)); 2983 } 2984 2985 // Mark const if we don't care about errno and that is the only 2986 // thing preventing the function from being const. This allows 2987 // IRgen to use LLVM intrinsics for such functions. 2988 if (!getLangOptions().MathErrno && 2989 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 2990 if (!FD->getAttr<ConstAttr>()) 2991 FD->addAttr(::new (Context) ConstAttr()); 2992 } 2993 } 2994 2995 IdentifierInfo *Name = FD->getIdentifier(); 2996 if (!Name) 2997 return; 2998 if ((!getLangOptions().CPlusPlus && 2999 FD->getDeclContext()->isTranslationUnit()) || 3000 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3001 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3002 LinkageSpecDecl::lang_c)) { 3003 // Okay: this could be a libc/libm/Objective-C function we know 3004 // about. 3005 } else 3006 return; 3007 3008 unsigned KnownID; 3009 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3010 if (KnownFunctionIDs[KnownID] == Name) 3011 break; 3012 3013 switch (KnownID) { 3014 case id_NSLog: 3015 case id_NSLogv: 3016 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3017 // FIXME: We known better than our headers. 3018 const_cast<FormatAttr *>(Format)->setType("printf"); 3019 } else 3020 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3021 break; 3022 3023 case id_asprintf: 3024 case id_vasprintf: 3025 if (!FD->getAttr<FormatAttr>()) 3026 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3027 break; 3028 3029 default: 3030 // Unknown function or known function without any attributes to 3031 // add. Do nothing. 3032 break; 3033 } 3034} 3035 3036TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 3037 Decl *LastDeclarator) { 3038 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3039 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3040 3041 // Scope manipulation handled by caller. 3042 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3043 D.getIdentifierLoc(), 3044 D.getIdentifier(), 3045 T); 3046 3047 if (TagType *TT = dyn_cast<TagType>(T)) { 3048 TagDecl *TD = TT->getDecl(); 3049 3050 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3051 // keep track of the TypedefDecl. 3052 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3053 TD->setTypedefForAnonDecl(NewTD); 3054 } 3055 3056 NewTD->setNextDeclarator(LastDeclarator); 3057 if (D.getInvalidType()) 3058 NewTD->setInvalidDecl(); 3059 return NewTD; 3060} 3061 3062/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3063/// former case, Name will be non-null. In the later case, Name will be null. 3064/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3065/// reference/declaration/definition of a tag. 3066Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3067 SourceLocation KWLoc, const CXXScopeSpec &SS, 3068 IdentifierInfo *Name, SourceLocation NameLoc, 3069 AttributeList *Attr) { 3070 // If this is not a definition, it must have a name. 3071 assert((Name != 0 || TK == TK_Definition) && 3072 "Nameless record must be a definition!"); 3073 3074 TagDecl::TagKind Kind; 3075 switch (TagSpec) { 3076 default: assert(0 && "Unknown tag type!"); 3077 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3078 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3079 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3080 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3081 } 3082 3083 DeclContext *SearchDC = CurContext; 3084 DeclContext *DC = CurContext; 3085 NamedDecl *PrevDecl = 0; 3086 3087 bool Invalid = false; 3088 3089 if (Name && SS.isNotEmpty()) { 3090 // We have a nested-name tag ('struct foo::bar'). 3091 3092 // Check for invalid 'foo::'. 3093 if (SS.isInvalid()) { 3094 Name = 0; 3095 goto CreateNewDecl; 3096 } 3097 3098 // FIXME: RequireCompleteDeclContext(SS)? 3099 DC = computeDeclContext(SS); 3100 SearchDC = DC; 3101 // Look-up name inside 'foo::'. 3102 PrevDecl = dyn_cast_or_null<TagDecl>( 3103 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3104 3105 // A tag 'foo::bar' must already exist. 3106 if (PrevDecl == 0) { 3107 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3108 Name = 0; 3109 goto CreateNewDecl; 3110 } 3111 } else if (Name) { 3112 // If this is a named struct, check to see if there was a previous forward 3113 // declaration or definition. 3114 // FIXME: We're looking into outer scopes here, even when we 3115 // shouldn't be. Doing so can result in ambiguities that we 3116 // shouldn't be diagnosing. 3117 LookupResult R = LookupName(S, Name, LookupTagName, 3118 /*RedeclarationOnly=*/(TK != TK_Reference)); 3119 if (R.isAmbiguous()) { 3120 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3121 // FIXME: This is not best way to recover from case like: 3122 // 3123 // struct S s; 3124 // 3125 // causes needless err_ovl_no_viable_function_in_init latter. 3126 Name = 0; 3127 PrevDecl = 0; 3128 Invalid = true; 3129 } 3130 else 3131 PrevDecl = R; 3132 3133 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3134 // FIXME: This makes sure that we ignore the contexts associated 3135 // with C structs, unions, and enums when looking for a matching 3136 // tag declaration or definition. See the similar lookup tweak 3137 // in Sema::LookupName; is there a better way to deal with this? 3138 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3139 SearchDC = SearchDC->getParent(); 3140 } 3141 } 3142 3143 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3144 // Maybe we will complain about the shadowed template parameter. 3145 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3146 // Just pretend that we didn't see the previous declaration. 3147 PrevDecl = 0; 3148 } 3149 3150 if (PrevDecl) { 3151 // Check whether the previous declaration is usable. 3152 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3153 3154 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3155 // If this is a use of a previous tag, or if the tag is already declared 3156 // in the same scope (so that the definition/declaration completes or 3157 // rementions the tag), reuse the decl. 3158 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3159 // Make sure that this wasn't declared as an enum and now used as a 3160 // struct or something similar. 3161 if (PrevTagDecl->getTagKind() != Kind) { 3162 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3163 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3164 // Recover by making this an anonymous redefinition. 3165 Name = 0; 3166 PrevDecl = 0; 3167 Invalid = true; 3168 } else { 3169 // If this is a use, just return the declaration we found. 3170 3171 // FIXME: In the future, return a variant or some other clue 3172 // for the consumer of this Decl to know it doesn't own it. 3173 // For our current ASTs this shouldn't be a problem, but will 3174 // need to be changed with DeclGroups. 3175 if (TK == TK_Reference) 3176 return PrevDecl; 3177 3178 // Diagnose attempts to redefine a tag. 3179 if (TK == TK_Definition) { 3180 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3181 Diag(NameLoc, diag::err_redefinition) << Name; 3182 Diag(Def->getLocation(), diag::note_previous_definition); 3183 // If this is a redefinition, recover by making this 3184 // struct be anonymous, which will make any later 3185 // references get the previous definition. 3186 Name = 0; 3187 PrevDecl = 0; 3188 Invalid = true; 3189 } else { 3190 // If the type is currently being defined, complain 3191 // about a nested redefinition. 3192 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3193 if (Tag->isBeingDefined()) { 3194 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3195 Diag(PrevTagDecl->getLocation(), 3196 diag::note_previous_definition); 3197 Name = 0; 3198 PrevDecl = 0; 3199 Invalid = true; 3200 } 3201 } 3202 3203 // Okay, this is definition of a previously declared or referenced 3204 // tag PrevDecl. We're going to create a new Decl for it. 3205 } 3206 } 3207 // If we get here we have (another) forward declaration or we 3208 // have a definition. Just create a new decl. 3209 } else { 3210 // If we get here, this is a definition of a new tag type in a nested 3211 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3212 // new decl/type. We set PrevDecl to NULL so that the entities 3213 // have distinct types. 3214 PrevDecl = 0; 3215 } 3216 // If we get here, we're going to create a new Decl. If PrevDecl 3217 // is non-NULL, it's a definition of the tag declared by 3218 // PrevDecl. If it's NULL, we have a new definition. 3219 } else { 3220 // PrevDecl is a namespace, template, or anything else 3221 // that lives in the IDNS_Tag identifier namespace. 3222 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3223 // The tag name clashes with a namespace name, issue an error and 3224 // recover by making this tag be anonymous. 3225 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3226 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3227 Name = 0; 3228 PrevDecl = 0; 3229 Invalid = true; 3230 } else { 3231 // The existing declaration isn't relevant to us; we're in a 3232 // new scope, so clear out the previous declaration. 3233 PrevDecl = 0; 3234 } 3235 } 3236 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3237 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3238 // C.scope.pdecl]p5: 3239 // -- for an elaborated-type-specifier of the form 3240 // 3241 // class-key identifier 3242 // 3243 // if the elaborated-type-specifier is used in the 3244 // decl-specifier-seq or parameter-declaration-clause of a 3245 // function defined in namespace scope, the identifier is 3246 // declared as a class-name in the namespace that contains 3247 // the declaration; otherwise, except as a friend 3248 // declaration, the identifier is declared in the smallest 3249 // non-class, non-function-prototype scope that contains the 3250 // declaration. 3251 // 3252 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3253 // C structs and unions. 3254 // 3255 // GNU C also supports this behavior as part of its incomplete 3256 // enum types extension, while GNU C++ does not. 3257 // 3258 // Find the context where we'll be declaring the tag. 3259 // FIXME: We would like to maintain the current DeclContext as the 3260 // lexical context, 3261 while (SearchDC->isRecord()) 3262 SearchDC = SearchDC->getParent(); 3263 3264 // Find the scope where we'll be declaring the tag. 3265 while (S->isClassScope() || 3266 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3267 ((S->getFlags() & Scope::DeclScope) == 0) || 3268 (S->getEntity() && 3269 ((DeclContext *)S->getEntity())->isTransparentContext())) 3270 S = S->getParent(); 3271 } 3272 3273CreateNewDecl: 3274 3275 // If there is an identifier, use the location of the identifier as the 3276 // location of the decl, otherwise use the location of the struct/union 3277 // keyword. 3278 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3279 3280 // Otherwise, create a new declaration. If there is a previous 3281 // declaration of the same entity, the two will be linked via 3282 // PrevDecl. 3283 TagDecl *New; 3284 3285 if (Kind == TagDecl::TK_enum) { 3286 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3287 // enum X { A, B, C } D; D should chain to X. 3288 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3289 cast_or_null<EnumDecl>(PrevDecl)); 3290 // If this is an undefined enum, warn. 3291 if (TK != TK_Definition && !Invalid) { 3292 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3293 : diag::ext_forward_ref_enum; 3294 Diag(Loc, DK); 3295 } 3296 } else { 3297 // struct/union/class 3298 3299 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3300 // struct X { int A; } D; D should chain to X. 3301 if (getLangOptions().CPlusPlus) 3302 // FIXME: Look for a way to use RecordDecl for simple structs. 3303 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3304 cast_or_null<CXXRecordDecl>(PrevDecl)); 3305 else 3306 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3307 cast_or_null<RecordDecl>(PrevDecl)); 3308 } 3309 3310 if (Kind != TagDecl::TK_enum) { 3311 // Handle #pragma pack: if the #pragma pack stack has non-default 3312 // alignment, make up a packed attribute for this decl. These 3313 // attributes are checked when the ASTContext lays out the 3314 // structure. 3315 // 3316 // It is important for implementing the correct semantics that this 3317 // happen here (in act on tag decl). The #pragma pack stack is 3318 // maintained as a result of parser callbacks which can occur at 3319 // many points during the parsing of a struct declaration (because 3320 // the #pragma tokens are effectively skipped over during the 3321 // parsing of the struct). 3322 if (unsigned Alignment = getPragmaPackAlignment()) 3323 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3324 } 3325 3326 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3327 // C++ [dcl.typedef]p3: 3328 // [...] Similarly, in a given scope, a class or enumeration 3329 // shall not be declared with the same name as a typedef-name 3330 // that is declared in that scope and refers to a type other 3331 // than the class or enumeration itself. 3332 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3333 TypedefDecl *PrevTypedef = 0; 3334 if (Lookup.getKind() == LookupResult::Found) 3335 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3336 3337 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3338 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3339 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3340 Diag(Loc, diag::err_tag_definition_of_typedef) 3341 << Context.getTypeDeclType(New) 3342 << PrevTypedef->getUnderlyingType(); 3343 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3344 Invalid = true; 3345 } 3346 } 3347 3348 if (Invalid) 3349 New->setInvalidDecl(); 3350 3351 if (Attr) 3352 ProcessDeclAttributeList(New, Attr); 3353 3354 // If we're declaring or defining a tag in function prototype scope 3355 // in C, note that this type can only be used within the function. 3356 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3357 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3358 3359 // Set the lexical context. If the tag has a C++ scope specifier, the 3360 // lexical context will be different from the semantic context. 3361 New->setLexicalDeclContext(CurContext); 3362 3363 if (TK == TK_Definition) 3364 New->startDefinition(); 3365 3366 // If this has an identifier, add it to the scope stack. 3367 if (Name) { 3368 S = getNonFieldDeclScope(S); 3369 PushOnScopeChains(New, S); 3370 } else { 3371 CurContext->addDecl(New); 3372 } 3373 3374 return New; 3375} 3376 3377void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3378 AdjustDeclIfTemplate(TagD); 3379 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3380 3381 // Enter the tag context. 3382 PushDeclContext(S, Tag); 3383 3384 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3385 FieldCollector->StartClass(); 3386 3387 if (Record->getIdentifier()) { 3388 // C++ [class]p2: 3389 // [...] The class-name is also inserted into the scope of the 3390 // class itself; this is known as the injected-class-name. For 3391 // purposes of access checking, the injected-class-name is treated 3392 // as if it were a public member name. 3393 RecordDecl *InjectedClassName 3394 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3395 CurContext, Record->getLocation(), 3396 Record->getIdentifier(), Record); 3397 InjectedClassName->setImplicit(); 3398 PushOnScopeChains(InjectedClassName, S); 3399 } 3400 } 3401} 3402 3403void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3404 AdjustDeclIfTemplate(TagD); 3405 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3406 3407 if (isa<CXXRecordDecl>(Tag)) 3408 FieldCollector->FinishClass(); 3409 3410 // Exit this scope of this tag's definition. 3411 PopDeclContext(); 3412 3413 // Notify the consumer that we've defined a tag. 3414 Consumer.HandleTagDeclDefinition(Tag); 3415} 3416 3417bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3418 QualType FieldTy, const Expr *BitWidth) { 3419 // C99 6.7.2.1p4 - verify the field type. 3420 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3421 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3422 // Handle incomplete types with specific error. 3423 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3424 return true; 3425 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3426 << FieldName << FieldTy << BitWidth->getSourceRange(); 3427 } 3428 3429 // If the bit-width is type- or value-dependent, don't try to check 3430 // it now. 3431 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3432 return false; 3433 3434 llvm::APSInt Value; 3435 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3436 return true; 3437 3438 // Zero-width bitfield is ok for anonymous field. 3439 if (Value == 0 && FieldName) 3440 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3441 3442 if (Value.isSigned() && Value.isNegative()) 3443 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3444 << FieldName << Value.toString(10); 3445 3446 if (!FieldTy->isDependentType()) { 3447 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3448 // FIXME: We won't need the 0 size once we check that the field type is valid. 3449 if (TypeSize && Value.getZExtValue() > TypeSize) 3450 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3451 << FieldName << (unsigned)TypeSize; 3452 } 3453 3454 return false; 3455} 3456 3457/// ActOnField - Each field of a struct/union/class is passed into this in order 3458/// to create a FieldDecl object for it. 3459Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3460 SourceLocation DeclStart, 3461 Declarator &D, ExprTy *BitfieldWidth) { 3462 3463 return HandleField(S, static_cast<RecordDecl*>(TagD), DeclStart, D, 3464 static_cast<Expr*>(BitfieldWidth), 3465 AS_public); 3466} 3467 3468/// HandleField - Analyze a field of a C struct or a C++ data member. 3469/// 3470FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3471 SourceLocation DeclStart, 3472 Declarator &D, Expr *BitWidth, 3473 AccessSpecifier AS) { 3474 IdentifierInfo *II = D.getIdentifier(); 3475 SourceLocation Loc = DeclStart; 3476 if (II) Loc = D.getIdentifierLoc(); 3477 3478 QualType T = GetTypeForDeclarator(D, S); 3479 3480 if (getLangOptions().CPlusPlus) { 3481 CheckExtraCXXDefaultArguments(D); 3482 3483 if (D.getDeclSpec().isVirtualSpecified()) 3484 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3485 diag::err_virtual_non_function); 3486 } 3487 3488 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3489 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3490 PrevDecl = 0; 3491 3492 FieldDecl *NewFD 3493 = CheckFieldDecl(II, T, Record, Loc, 3494 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3495 BitWidth, AS, PrevDecl, &D); 3496 if (NewFD->isInvalidDecl() && PrevDecl) { 3497 // Don't introduce NewFD into scope; there's already something 3498 // with the same name in the same scope. 3499 } else if (II) { 3500 PushOnScopeChains(NewFD, S); 3501 } else 3502 Record->addDecl(NewFD); 3503 3504 return NewFD; 3505} 3506 3507/// \brief Build a new FieldDecl and check its well-formedness. 3508/// 3509/// This routine builds a new FieldDecl given the fields name, type, 3510/// record, etc. \p PrevDecl should refer to any previous declaration 3511/// with the same name and in the same scope as the field to be 3512/// created. 3513/// 3514/// \returns a new FieldDecl. 3515/// 3516/// \todo The Declarator argument is a hack. It will be removed once 3517FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3518 RecordDecl *Record, SourceLocation Loc, 3519 bool Mutable, Expr *BitWidth, 3520 AccessSpecifier AS, NamedDecl *PrevDecl, 3521 Declarator *D) { 3522 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3523 bool InvalidDecl = false; 3524 3525 // If we receive a broken type, recover by assuming 'int' and 3526 // marking this declaration as invalid. 3527 if (T.isNull()) { 3528 InvalidDecl = true; 3529 T = Context.IntTy; 3530 } 3531 3532 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3533 // than a variably modified type. 3534 if (T->isVariablyModifiedType()) { 3535 bool SizeIsNegative; 3536 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3537 SizeIsNegative); 3538 if (!FixedTy.isNull()) { 3539 Diag(Loc, diag::warn_illegal_constant_array_size); 3540 T = FixedTy; 3541 } else { 3542 if (SizeIsNegative) 3543 Diag(Loc, diag::err_typecheck_negative_array_size); 3544 else 3545 Diag(Loc, diag::err_typecheck_field_variable_size); 3546 T = Context.IntTy; 3547 InvalidDecl = true; 3548 } 3549 } 3550 3551 // Fields can not have abstract class types 3552 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3553 AbstractFieldType)) 3554 InvalidDecl = true; 3555 3556 // If this is declared as a bit-field, check the bit-field. 3557 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3558 InvalidDecl = true; 3559 DeleteExpr(BitWidth); 3560 BitWidth = 0; 3561 } 3562 3563 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3564 Mutable); 3565 3566 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3567 Diag(Loc, diag::err_duplicate_member) << II; 3568 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3569 NewFD->setInvalidDecl(); 3570 Record->setInvalidDecl(); 3571 } 3572 3573 if (getLangOptions().CPlusPlus && !T->isPODType()) 3574 cast<CXXRecordDecl>(Record)->setPOD(false); 3575 3576 // FIXME: We need to pass in the attributes given an AST 3577 // representation, not a parser representation. 3578 if (D) 3579 ProcessDeclAttributes(NewFD, *D); 3580 3581 if (T.isObjCGCWeak()) 3582 Diag(Loc, diag::warn_attribute_weak_on_field); 3583 3584 if (InvalidDecl) 3585 NewFD->setInvalidDecl(); 3586 3587 NewFD->setAccess(AS); 3588 3589 // C++ [dcl.init.aggr]p1: 3590 // An aggregate is an array or a class (clause 9) with [...] no 3591 // private or protected non-static data members (clause 11). 3592 // A POD must be an aggregate. 3593 if (getLangOptions().CPlusPlus && 3594 (AS == AS_private || AS == AS_protected)) { 3595 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3596 CXXRecord->setAggregate(false); 3597 CXXRecord->setPOD(false); 3598 } 3599 3600 return NewFD; 3601} 3602 3603/// TranslateIvarVisibility - Translate visibility from a token ID to an 3604/// AST enum value. 3605static ObjCIvarDecl::AccessControl 3606TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3607 switch (ivarVisibility) { 3608 default: assert(0 && "Unknown visitibility kind"); 3609 case tok::objc_private: return ObjCIvarDecl::Private; 3610 case tok::objc_public: return ObjCIvarDecl::Public; 3611 case tok::objc_protected: return ObjCIvarDecl::Protected; 3612 case tok::objc_package: return ObjCIvarDecl::Package; 3613 } 3614} 3615 3616/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3617/// in order to create an IvarDecl object for it. 3618Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3619 SourceLocation DeclStart, 3620 Declarator &D, ExprTy *BitfieldWidth, 3621 tok::ObjCKeywordKind Visibility) { 3622 3623 IdentifierInfo *II = D.getIdentifier(); 3624 Expr *BitWidth = (Expr*)BitfieldWidth; 3625 SourceLocation Loc = DeclStart; 3626 if (II) Loc = D.getIdentifierLoc(); 3627 3628 // FIXME: Unnamed fields can be handled in various different ways, for 3629 // example, unnamed unions inject all members into the struct namespace! 3630 3631 QualType T = GetTypeForDeclarator(D, S); 3632 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3633 bool InvalidDecl = false; 3634 3635 if (BitWidth) { 3636 // 6.7.2.1p3, 6.7.2.1p4 3637 if (VerifyBitField(Loc, II, T, BitWidth)) { 3638 InvalidDecl = true; 3639 DeleteExpr(BitWidth); 3640 BitWidth = 0; 3641 } 3642 } else { 3643 // Not a bitfield. 3644 3645 // validate II. 3646 3647 } 3648 3649 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3650 // than a variably modified type. 3651 if (T->isVariablyModifiedType()) { 3652 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3653 InvalidDecl = true; 3654 } 3655 3656 // Get the visibility (access control) for this ivar. 3657 ObjCIvarDecl::AccessControl ac = 3658 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3659 : ObjCIvarDecl::None; 3660 3661 // Construct the decl. 3662 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3663 (Expr *)BitfieldWidth); 3664 3665 if (II) { 3666 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3667 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3668 && !isa<TagDecl>(PrevDecl)) { 3669 Diag(Loc, diag::err_duplicate_member) << II; 3670 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3671 NewID->setInvalidDecl(); 3672 } 3673 } 3674 3675 // Process attributes attached to the ivar. 3676 ProcessDeclAttributes(NewID, D); 3677 3678 if (D.getInvalidType() || InvalidDecl) 3679 NewID->setInvalidDecl(); 3680 3681 if (II) { 3682 // FIXME: When interfaces are DeclContexts, we'll need to add 3683 // these to the interface. 3684 S->AddDecl(NewID); 3685 IdResolver.AddDecl(NewID); 3686 } 3687 3688 return NewID; 3689} 3690 3691void Sema::ActOnFields(Scope* S, 3692 SourceLocation RecLoc, DeclTy *RecDecl, 3693 DeclTy **Fields, unsigned NumFields, 3694 SourceLocation LBrac, SourceLocation RBrac, 3695 AttributeList *Attr) { 3696 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3697 assert(EnclosingDecl && "missing record or interface decl"); 3698 3699 // If the decl this is being inserted into is invalid, then it may be a 3700 // redeclaration or some other bogus case. Don't try to add fields to it. 3701 if (EnclosingDecl->isInvalidDecl()) { 3702 // FIXME: Deallocate fields? 3703 return; 3704 } 3705 3706 3707 // Verify that all the fields are okay. 3708 unsigned NumNamedMembers = 0; 3709 llvm::SmallVector<FieldDecl*, 32> RecFields; 3710 3711 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3712 for (unsigned i = 0; i != NumFields; ++i) { 3713 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3714 assert(FD && "missing field decl"); 3715 3716 // Get the type for the field. 3717 Type *FDTy = FD->getType().getTypePtr(); 3718 3719 if (!FD->isAnonymousStructOrUnion()) { 3720 // Remember all fields written by the user. 3721 RecFields.push_back(FD); 3722 } 3723 3724 // If the field is already invalid for some reason, don't emit more 3725 // diagnostics about it. 3726 if (FD->isInvalidDecl()) 3727 continue; 3728 3729 // C99 6.7.2.1p2 - A field may not be a function type. 3730 if (FDTy->isFunctionType()) { 3731 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3732 << FD->getDeclName(); 3733 FD->setInvalidDecl(); 3734 EnclosingDecl->setInvalidDecl(); 3735 continue; 3736 } 3737 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3738 if (FDTy->isIncompleteType()) { 3739 if (!Record) { // Incomplete ivar type is always an error. 3740 RequireCompleteType(FD->getLocation(), FD->getType(), 3741 diag::err_field_incomplete); 3742 FD->setInvalidDecl(); 3743 EnclosingDecl->setInvalidDecl(); 3744 continue; 3745 } 3746 if (i != NumFields-1 || // ... that the last member ... 3747 !Record->isStruct() || // ... of a structure ... 3748 !FDTy->isArrayType()) { //... may have incomplete array type. 3749 RequireCompleteType(FD->getLocation(), FD->getType(), 3750 diag::err_field_incomplete); 3751 FD->setInvalidDecl(); 3752 EnclosingDecl->setInvalidDecl(); 3753 continue; 3754 } 3755 if (NumNamedMembers < 1) { //... must have more than named member ... 3756 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3757 << FD->getDeclName(); 3758 FD->setInvalidDecl(); 3759 EnclosingDecl->setInvalidDecl(); 3760 continue; 3761 } 3762 // Okay, we have a legal flexible array member at the end of the struct. 3763 if (Record) 3764 Record->setHasFlexibleArrayMember(true); 3765 } 3766 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3767 /// field of another structure or the element of an array. 3768 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3769 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3770 // If this is a member of a union, then entire union becomes "flexible". 3771 if (Record && Record->isUnion()) { 3772 Record->setHasFlexibleArrayMember(true); 3773 } else { 3774 // If this is a struct/class and this is not the last element, reject 3775 // it. Note that GCC supports variable sized arrays in the middle of 3776 // structures. 3777 if (i != NumFields-1) 3778 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3779 << FD->getDeclName(); 3780 else { 3781 // We support flexible arrays at the end of structs in 3782 // other structs as an extension. 3783 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3784 << FD->getDeclName(); 3785 if (Record) 3786 Record->setHasFlexibleArrayMember(true); 3787 } 3788 } 3789 } 3790 } 3791 /// A field cannot be an Objective-c object 3792 if (FDTy->isObjCInterfaceType()) { 3793 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3794 FD->setInvalidDecl(); 3795 EnclosingDecl->setInvalidDecl(); 3796 continue; 3797 } 3798 // Keep track of the number of named members. 3799 if (FD->getIdentifier()) 3800 ++NumNamedMembers; 3801 } 3802 3803 // Okay, we successfully defined 'Record'. 3804 if (Record) { 3805 Record->completeDefinition(Context); 3806 } else { 3807 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3808 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3809 ID->setIVarList(ClsFields, RecFields.size(), Context); 3810 ID->setLocEnd(RBrac); 3811 3812 // Must enforce the rule that ivars in the base classes may not be 3813 // duplicates. 3814 if (ID->getSuperClass()) { 3815 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3816 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3817 ObjCIvarDecl* Ivar = (*IVI); 3818 IdentifierInfo *II = Ivar->getIdentifier(); 3819 ObjCIvarDecl* prevIvar = 3820 ID->getSuperClass()->lookupInstanceVariable(II); 3821 if (prevIvar) { 3822 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3823 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3824 } 3825 } 3826 } 3827 } else if (ObjCImplementationDecl *IMPDecl = 3828 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3829 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3830 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3831 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3832 } 3833 } 3834 3835 if (Attr) 3836 ProcessDeclAttributeList(Record, Attr); 3837} 3838 3839EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3840 EnumConstantDecl *LastEnumConst, 3841 SourceLocation IdLoc, 3842 IdentifierInfo *Id, 3843 ExprArg val) { 3844 Expr *Val = (Expr *)val.get(); 3845 3846 llvm::APSInt EnumVal(32); 3847 QualType EltTy; 3848 if (Val && !Val->isTypeDependent()) { 3849 // Make sure to promote the operand type to int. 3850 UsualUnaryConversions(Val); 3851 if (Val != val.get()) { 3852 val.release(); 3853 val = Val; 3854 } 3855 3856 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3857 SourceLocation ExpLoc; 3858 if (!Val->isValueDependent() && 3859 VerifyIntegerConstantExpression(Val, &EnumVal)) { 3860 Val = 0; 3861 } else { 3862 EltTy = Val->getType(); 3863 } 3864 } 3865 3866 if (!Val) { 3867 if (LastEnumConst) { 3868 // Assign the last value + 1. 3869 EnumVal = LastEnumConst->getInitVal(); 3870 ++EnumVal; 3871 3872 // Check for overflow on increment. 3873 if (EnumVal < LastEnumConst->getInitVal()) 3874 Diag(IdLoc, diag::warn_enum_value_overflow); 3875 3876 EltTy = LastEnumConst->getType(); 3877 } else { 3878 // First value, set to zero. 3879 EltTy = Context.IntTy; 3880 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3881 } 3882 } 3883 3884 val.release(); 3885 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 3886 Val, EnumVal); 3887} 3888 3889 3890Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3891 DeclTy *lastEnumConst, 3892 SourceLocation IdLoc, IdentifierInfo *Id, 3893 SourceLocation EqualLoc, ExprTy *val) { 3894 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3895 EnumConstantDecl *LastEnumConst = 3896 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3897 Expr *Val = static_cast<Expr*>(val); 3898 3899 // The scope passed in may not be a decl scope. Zip up the scope tree until 3900 // we find one that is. 3901 S = getNonFieldDeclScope(S); 3902 3903 // Verify that there isn't already something declared with this name in this 3904 // scope. 3905 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3906 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3907 // Maybe we will complain about the shadowed template parameter. 3908 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3909 // Just pretend that we didn't see the previous declaration. 3910 PrevDecl = 0; 3911 } 3912 3913 if (PrevDecl) { 3914 // When in C++, we may get a TagDecl with the same name; in this case the 3915 // enum constant will 'hide' the tag. 3916 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3917 "Received TagDecl when not in C++!"); 3918 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3919 if (isa<EnumConstantDecl>(PrevDecl)) 3920 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3921 else 3922 Diag(IdLoc, diag::err_redefinition) << Id; 3923 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3924 if (Val) Val->Destroy(Context); 3925 return 0; 3926 } 3927 } 3928 3929 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 3930 IdLoc, Id, Owned(Val)); 3931 3932 // Register this decl in the current scope stack. 3933 if (New) 3934 PushOnScopeChains(New, S); 3935 3936 return New; 3937} 3938 3939// FIXME: For consistency with ActOnFields(), we should have the parser 3940// pass in the source location for the left/right braces. 3941void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3942 DeclTy **Elements, unsigned NumElements) { 3943 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3944 QualType EnumType = Context.getTypeDeclType(Enum); 3945 3946 // TODO: If the result value doesn't fit in an int, it must be a long or long 3947 // long value. ISO C does not support this, but GCC does as an extension, 3948 // emit a warning. 3949 unsigned IntWidth = Context.Target.getIntWidth(); 3950 3951 // Verify that all the values are okay, compute the size of the values, and 3952 // reverse the list. 3953 unsigned NumNegativeBits = 0; 3954 unsigned NumPositiveBits = 0; 3955 3956 // Keep track of whether all elements have type int. 3957 bool AllElementsInt = true; 3958 3959 for (unsigned i = 0; i != NumElements; ++i) { 3960 EnumConstantDecl *ECD = 3961 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3962 if (!ECD) continue; // Already issued a diagnostic. 3963 3964 // If the enum value doesn't fit in an int, emit an extension warning. 3965 const llvm::APSInt &InitVal = ECD->getInitVal(); 3966 assert(InitVal.getBitWidth() >= IntWidth && 3967 "Should have promoted value to int"); 3968 if (InitVal.getBitWidth() > IntWidth) { 3969 llvm::APSInt V(InitVal); 3970 V.trunc(IntWidth); 3971 V.extend(InitVal.getBitWidth()); 3972 if (V != InitVal) 3973 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3974 << InitVal.toString(10); 3975 } 3976 3977 // Keep track of the size of positive and negative values. 3978 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3979 NumPositiveBits = std::max(NumPositiveBits, 3980 (unsigned)InitVal.getActiveBits()); 3981 else 3982 NumNegativeBits = std::max(NumNegativeBits, 3983 (unsigned)InitVal.getMinSignedBits()); 3984 3985 // Keep track of whether every enum element has type int (very commmon). 3986 if (AllElementsInt) 3987 AllElementsInt = ECD->getType() == Context.IntTy; 3988 } 3989 3990 // Figure out the type that should be used for this enum. 3991 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3992 QualType BestType; 3993 unsigned BestWidth; 3994 3995 if (NumNegativeBits) { 3996 // If there is a negative value, figure out the smallest integer type (of 3997 // int/long/longlong) that fits. 3998 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3999 BestType = Context.IntTy; 4000 BestWidth = IntWidth; 4001 } else { 4002 BestWidth = Context.Target.getLongWidth(); 4003 4004 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4005 BestType = Context.LongTy; 4006 else { 4007 BestWidth = Context.Target.getLongLongWidth(); 4008 4009 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4010 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4011 BestType = Context.LongLongTy; 4012 } 4013 } 4014 } else { 4015 // If there is no negative value, figure out which of uint, ulong, ulonglong 4016 // fits. 4017 if (NumPositiveBits <= IntWidth) { 4018 BestType = Context.UnsignedIntTy; 4019 BestWidth = IntWidth; 4020 } else if (NumPositiveBits <= 4021 (BestWidth = Context.Target.getLongWidth())) { 4022 BestType = Context.UnsignedLongTy; 4023 } else { 4024 BestWidth = Context.Target.getLongLongWidth(); 4025 assert(NumPositiveBits <= BestWidth && 4026 "How could an initializer get larger than ULL?"); 4027 BestType = Context.UnsignedLongLongTy; 4028 } 4029 } 4030 4031 // Loop over all of the enumerator constants, changing their types to match 4032 // the type of the enum if needed. 4033 for (unsigned i = 0; i != NumElements; ++i) { 4034 EnumConstantDecl *ECD = 4035 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 4036 if (!ECD) continue; // Already issued a diagnostic. 4037 4038 // Standard C says the enumerators have int type, but we allow, as an 4039 // extension, the enumerators to be larger than int size. If each 4040 // enumerator value fits in an int, type it as an int, otherwise type it the 4041 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4042 // that X has type 'int', not 'unsigned'. 4043 if (ECD->getType() == Context.IntTy) { 4044 // Make sure the init value is signed. 4045 llvm::APSInt IV = ECD->getInitVal(); 4046 IV.setIsSigned(true); 4047 ECD->setInitVal(IV); 4048 4049 if (getLangOptions().CPlusPlus) 4050 // C++ [dcl.enum]p4: Following the closing brace of an 4051 // enum-specifier, each enumerator has the type of its 4052 // enumeration. 4053 ECD->setType(EnumType); 4054 continue; // Already int type. 4055 } 4056 4057 // Determine whether the value fits into an int. 4058 llvm::APSInt InitVal = ECD->getInitVal(); 4059 bool FitsInInt; 4060 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4061 FitsInInt = InitVal.getActiveBits() < IntWidth; 4062 else 4063 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4064 4065 // If it fits into an integer type, force it. Otherwise force it to match 4066 // the enum decl type. 4067 QualType NewTy; 4068 unsigned NewWidth; 4069 bool NewSign; 4070 if (FitsInInt) { 4071 NewTy = Context.IntTy; 4072 NewWidth = IntWidth; 4073 NewSign = true; 4074 } else if (ECD->getType() == BestType) { 4075 // Already the right type! 4076 if (getLangOptions().CPlusPlus) 4077 // C++ [dcl.enum]p4: Following the closing brace of an 4078 // enum-specifier, each enumerator has the type of its 4079 // enumeration. 4080 ECD->setType(EnumType); 4081 continue; 4082 } else { 4083 NewTy = BestType; 4084 NewWidth = BestWidth; 4085 NewSign = BestType->isSignedIntegerType(); 4086 } 4087 4088 // Adjust the APSInt value. 4089 InitVal.extOrTrunc(NewWidth); 4090 InitVal.setIsSigned(NewSign); 4091 ECD->setInitVal(InitVal); 4092 4093 // Adjust the Expr initializer and type. 4094 if (ECD->getInitExpr()) 4095 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4096 /*isLvalue=*/false)); 4097 if (getLangOptions().CPlusPlus) 4098 // C++ [dcl.enum]p4: Following the closing brace of an 4099 // enum-specifier, each enumerator has the type of its 4100 // enumeration. 4101 ECD->setType(EnumType); 4102 else 4103 ECD->setType(NewTy); 4104 } 4105 4106 Enum->completeDefinition(Context, BestType); 4107} 4108 4109Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4110 ExprArg expr) { 4111 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4112 4113 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 4114} 4115 4116