SemaDecl.cpp revision d475b8d9e6f5ff0e6ab8d15667ce8a64c7cb9a4d
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 // 885 // This is also C++ [dcl.fct]p6. 886 if (!Param->isInvalidDecl() && 887 RequireCompleteType(Param->getLocation(), Param->getType(), 888 diag::err_typecheck_decl_incomplete_type)) { 889 Param->setInvalidDecl(); 890 HasInvalidParm = true; 891 } 892 893 // C99 6.9.1p5: If the declarator includes a parameter type list, the 894 // declaration of each parameter shall include an identifier. 895 if (Param->getIdentifier() == 0 && 896 !Param->isImplicit() && 897 !getLangOptions().CPlusPlus) 898 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 899 } 900 901 return HasInvalidParm; 902} 903 904/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 905/// no declarator (e.g. "struct foo;") is parsed. 906Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 907 TagDecl *Tag = 0; 908 if (DS.getTypeSpecType() == DeclSpec::TST_class || 909 DS.getTypeSpecType() == DeclSpec::TST_struct || 910 DS.getTypeSpecType() == DeclSpec::TST_union || 911 DS.getTypeSpecType() == DeclSpec::TST_enum) 912 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 913 914 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 915 if (!Record->getDeclName() && Record->isDefinition() && 916 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 917 if (getLangOptions().CPlusPlus || 918 Record->getDeclContext()->isRecord()) 919 return BuildAnonymousStructOrUnion(S, DS, Record); 920 921 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 922 << DS.getSourceRange(); 923 } 924 925 // Microsoft allows unnamed struct/union fields. Don't complain 926 // about them. 927 // FIXME: Should we support Microsoft's extensions in this area? 928 if (Record->getDeclName() && getLangOptions().Microsoft) 929 return Tag; 930 } 931 932 if (!DS.isMissingDeclaratorOk() && 933 DS.getTypeSpecType() != DeclSpec::TST_error) { 934 // Warn about typedefs of enums without names, since this is an 935 // extension in both Microsoft an GNU. 936 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 937 Tag && isa<EnumDecl>(Tag)) { 938 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 939 << DS.getSourceRange(); 940 return Tag; 941 } 942 943 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 944 << DS.getSourceRange(); 945 return 0; 946 } 947 948 return Tag; 949} 950 951/// InjectAnonymousStructOrUnionMembers - Inject the members of the 952/// anonymous struct or union AnonRecord into the owning context Owner 953/// and scope S. This routine will be invoked just after we realize 954/// that an unnamed union or struct is actually an anonymous union or 955/// struct, e.g., 956/// 957/// @code 958/// union { 959/// int i; 960/// float f; 961/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 962/// // f into the surrounding scope.x 963/// @endcode 964/// 965/// This routine is recursive, injecting the names of nested anonymous 966/// structs/unions into the owning context and scope as well. 967bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 968 RecordDecl *AnonRecord) { 969 bool Invalid = false; 970 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 971 FEnd = AnonRecord->field_end(); 972 F != FEnd; ++F) { 973 if ((*F)->getDeclName()) { 974 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 975 LookupOrdinaryName, true); 976 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 977 // C++ [class.union]p2: 978 // The names of the members of an anonymous union shall be 979 // distinct from the names of any other entity in the 980 // scope in which the anonymous union is declared. 981 unsigned diagKind 982 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 983 : diag::err_anonymous_struct_member_redecl; 984 Diag((*F)->getLocation(), diagKind) 985 << (*F)->getDeclName(); 986 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 987 Invalid = true; 988 } else { 989 // C++ [class.union]p2: 990 // For the purpose of name lookup, after the anonymous union 991 // definition, the members of the anonymous union are 992 // considered to have been defined in the scope in which the 993 // anonymous union is declared. 994 Owner->makeDeclVisibleInContext(*F); 995 S->AddDecl(*F); 996 IdResolver.AddDecl(*F); 997 } 998 } else if (const RecordType *InnerRecordType 999 = (*F)->getType()->getAsRecordType()) { 1000 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1001 if (InnerRecord->isAnonymousStructOrUnion()) 1002 Invalid = Invalid || 1003 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1004 } 1005 } 1006 1007 return Invalid; 1008} 1009 1010/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1011/// anonymous structure or union. Anonymous unions are a C++ feature 1012/// (C++ [class.union]) and a GNU C extension; anonymous structures 1013/// are a GNU C and GNU C++ extension. 1014Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1015 RecordDecl *Record) { 1016 DeclContext *Owner = Record->getDeclContext(); 1017 1018 // Diagnose whether this anonymous struct/union is an extension. 1019 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1020 Diag(Record->getLocation(), diag::ext_anonymous_union); 1021 else if (!Record->isUnion()) 1022 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1023 1024 // C and C++ require different kinds of checks for anonymous 1025 // structs/unions. 1026 bool Invalid = false; 1027 if (getLangOptions().CPlusPlus) { 1028 const char* PrevSpec = 0; 1029 // C++ [class.union]p3: 1030 // Anonymous unions declared in a named namespace or in the 1031 // global namespace shall be declared static. 1032 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1033 (isa<TranslationUnitDecl>(Owner) || 1034 (isa<NamespaceDecl>(Owner) && 1035 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1036 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1037 Invalid = true; 1038 1039 // Recover by adding 'static'. 1040 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1041 } 1042 // C++ [class.union]p3: 1043 // A storage class is not allowed in a declaration of an 1044 // anonymous union in a class scope. 1045 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1046 isa<RecordDecl>(Owner)) { 1047 Diag(DS.getStorageClassSpecLoc(), 1048 diag::err_anonymous_union_with_storage_spec); 1049 Invalid = true; 1050 1051 // Recover by removing the storage specifier. 1052 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1053 PrevSpec); 1054 } 1055 1056 // C++ [class.union]p2: 1057 // The member-specification of an anonymous union shall only 1058 // define non-static data members. [Note: nested types and 1059 // functions cannot be declared within an anonymous union. ] 1060 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1061 MemEnd = Record->decls_end(); 1062 Mem != MemEnd; ++Mem) { 1063 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1064 // C++ [class.union]p3: 1065 // An anonymous union shall not have private or protected 1066 // members (clause 11). 1067 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1068 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1069 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1070 Invalid = true; 1071 } 1072 } else if ((*Mem)->isImplicit()) { 1073 // Any implicit members are fine. 1074 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1075 // This is a type that showed up in an 1076 // elaborated-type-specifier inside the anonymous struct or 1077 // union, but which actually declares a type outside of the 1078 // anonymous struct or union. It's okay. 1079 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1080 if (!MemRecord->isAnonymousStructOrUnion() && 1081 MemRecord->getDeclName()) { 1082 // This is a nested type declaration. 1083 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1084 << (int)Record->isUnion(); 1085 Invalid = true; 1086 } 1087 } else { 1088 // We have something that isn't a non-static data 1089 // member. Complain about it. 1090 unsigned DK = diag::err_anonymous_record_bad_member; 1091 if (isa<TypeDecl>(*Mem)) 1092 DK = diag::err_anonymous_record_with_type; 1093 else if (isa<FunctionDecl>(*Mem)) 1094 DK = diag::err_anonymous_record_with_function; 1095 else if (isa<VarDecl>(*Mem)) 1096 DK = diag::err_anonymous_record_with_static; 1097 Diag((*Mem)->getLocation(), DK) 1098 << (int)Record->isUnion(); 1099 Invalid = true; 1100 } 1101 } 1102 } 1103 1104 if (!Record->isUnion() && !Owner->isRecord()) { 1105 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1106 << (int)getLangOptions().CPlusPlus; 1107 Invalid = true; 1108 } 1109 1110 // Create a declaration for this anonymous struct/union. 1111 NamedDecl *Anon = 0; 1112 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1113 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1114 /*IdentifierInfo=*/0, 1115 Context.getTypeDeclType(Record), 1116 /*BitWidth=*/0, /*Mutable=*/false); 1117 Anon->setAccess(AS_public); 1118 if (getLangOptions().CPlusPlus) 1119 FieldCollector->Add(cast<FieldDecl>(Anon)); 1120 } else { 1121 VarDecl::StorageClass SC; 1122 switch (DS.getStorageClassSpec()) { 1123 default: assert(0 && "Unknown storage class!"); 1124 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1125 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1126 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1127 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1128 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1129 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1130 case DeclSpec::SCS_mutable: 1131 // mutable can only appear on non-static class members, so it's always 1132 // an error here 1133 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1134 Invalid = true; 1135 SC = VarDecl::None; 1136 break; 1137 } 1138 1139 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1140 /*IdentifierInfo=*/0, 1141 Context.getTypeDeclType(Record), 1142 SC, DS.getSourceRange().getBegin()); 1143 } 1144 Anon->setImplicit(); 1145 1146 // Add the anonymous struct/union object to the current 1147 // context. We'll be referencing this object when we refer to one of 1148 // its members. 1149 Owner->addDecl(Anon); 1150 1151 // Inject the members of the anonymous struct/union into the owning 1152 // context and into the identifier resolver chain for name lookup 1153 // purposes. 1154 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1155 Invalid = true; 1156 1157 // Mark this as an anonymous struct/union type. Note that we do not 1158 // do this until after we have already checked and injected the 1159 // members of this anonymous struct/union type, because otherwise 1160 // the members could be injected twice: once by DeclContext when it 1161 // builds its lookup table, and once by 1162 // InjectAnonymousStructOrUnionMembers. 1163 Record->setAnonymousStructOrUnion(true); 1164 1165 if (Invalid) 1166 Anon->setInvalidDecl(); 1167 1168 return Anon; 1169} 1170 1171 1172/// GetNameForDeclarator - Determine the full declaration name for the 1173/// given Declarator. 1174DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1175 switch (D.getKind()) { 1176 case Declarator::DK_Abstract: 1177 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1178 return DeclarationName(); 1179 1180 case Declarator::DK_Normal: 1181 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1182 return DeclarationName(D.getIdentifier()); 1183 1184 case Declarator::DK_Constructor: { 1185 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1186 Ty = Context.getCanonicalType(Ty); 1187 return Context.DeclarationNames.getCXXConstructorName(Ty); 1188 } 1189 1190 case Declarator::DK_Destructor: { 1191 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1192 Ty = Context.getCanonicalType(Ty); 1193 return Context.DeclarationNames.getCXXDestructorName(Ty); 1194 } 1195 1196 case Declarator::DK_Conversion: { 1197 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1198 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1199 Ty = Context.getCanonicalType(Ty); 1200 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1201 } 1202 1203 case Declarator::DK_Operator: 1204 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1205 return Context.DeclarationNames.getCXXOperatorName( 1206 D.getOverloadedOperator()); 1207 } 1208 1209 assert(false && "Unknown name kind"); 1210 return DeclarationName(); 1211} 1212 1213/// isNearlyMatchingFunction - Determine whether the C++ functions 1214/// Declaration and Definition are "nearly" matching. This heuristic 1215/// is used to improve diagnostics in the case where an out-of-line 1216/// function definition doesn't match any declaration within 1217/// the class or namespace. 1218static bool isNearlyMatchingFunction(ASTContext &Context, 1219 FunctionDecl *Declaration, 1220 FunctionDecl *Definition) { 1221 if (Declaration->param_size() != Definition->param_size()) 1222 return false; 1223 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1224 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1225 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1226 1227 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1228 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1229 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1230 return false; 1231 } 1232 1233 return true; 1234} 1235 1236Sema::DeclTy * 1237Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1238 bool IsFunctionDefinition) { 1239 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1240 DeclarationName Name = GetNameForDeclarator(D); 1241 1242 // All of these full declarators require an identifier. If it doesn't have 1243 // one, the ParsedFreeStandingDeclSpec action should be used. 1244 if (!Name) { 1245 if (!D.getInvalidType()) // Reject this if we think it is valid. 1246 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1247 diag::err_declarator_need_ident) 1248 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1249 return 0; 1250 } 1251 1252 // The scope passed in may not be a decl scope. Zip up the scope tree until 1253 // we find one that is. 1254 while ((S->getFlags() & Scope::DeclScope) == 0 || 1255 (S->getFlags() & Scope::TemplateParamScope) != 0) 1256 S = S->getParent(); 1257 1258 DeclContext *DC; 1259 NamedDecl *PrevDecl; 1260 NamedDecl *New; 1261 bool InvalidDecl = false; 1262 1263 QualType R = GetTypeForDeclarator(D, S); 1264 if (R.isNull()) { 1265 InvalidDecl = true; 1266 R = Context.IntTy; 1267 } 1268 1269 // See if this is a redefinition of a variable in the same scope. 1270 if (D.getCXXScopeSpec().isInvalid()) { 1271 DC = CurContext; 1272 PrevDecl = 0; 1273 InvalidDecl = true; 1274 } else if (!D.getCXXScopeSpec().isSet()) { 1275 LookupNameKind NameKind = LookupOrdinaryName; 1276 1277 // If the declaration we're planning to build will be a function 1278 // or object with linkage, then look for another declaration with 1279 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1280 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1281 /* Do nothing*/; 1282 else if (R->isFunctionType()) { 1283 if (CurContext->isFunctionOrMethod()) 1284 NameKind = LookupRedeclarationWithLinkage; 1285 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1286 NameKind = LookupRedeclarationWithLinkage; 1287 1288 DC = CurContext; 1289 PrevDecl = LookupName(S, Name, NameKind, true, 1290 D.getDeclSpec().getStorageClassSpec() != 1291 DeclSpec::SCS_static, 1292 D.getIdentifierLoc()); 1293 } else { // Something like "int foo::x;" 1294 DC = computeDeclContext(D.getCXXScopeSpec()); 1295 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1296 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1297 1298 // C++ 7.3.1.2p2: 1299 // Members (including explicit specializations of templates) of a named 1300 // namespace can also be defined outside that namespace by explicit 1301 // qualification of the name being defined, provided that the entity being 1302 // defined was already declared in the namespace and the definition appears 1303 // after the point of declaration in a namespace that encloses the 1304 // declarations namespace. 1305 // 1306 // Note that we only check the context at this point. We don't yet 1307 // have enough information to make sure that PrevDecl is actually 1308 // the declaration we want to match. For example, given: 1309 // 1310 // class X { 1311 // void f(); 1312 // void f(float); 1313 // }; 1314 // 1315 // void X::f(int) { } // ill-formed 1316 // 1317 // In this case, PrevDecl will point to the overload set 1318 // containing the two f's declared in X, but neither of them 1319 // matches. 1320 1321 // First check whether we named the global scope. 1322 if (isa<TranslationUnitDecl>(DC)) { 1323 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1324 << Name << D.getCXXScopeSpec().getRange(); 1325 } else if (!CurContext->Encloses(DC)) { 1326 // The qualifying scope doesn't enclose the original declaration. 1327 // Emit diagnostic based on current scope. 1328 SourceLocation L = D.getIdentifierLoc(); 1329 SourceRange R = D.getCXXScopeSpec().getRange(); 1330 if (isa<FunctionDecl>(CurContext)) 1331 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1332 else 1333 Diag(L, diag::err_invalid_declarator_scope) 1334 << Name << cast<NamedDecl>(DC) << R; 1335 InvalidDecl = true; 1336 } 1337 } 1338 1339 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1340 // Maybe we will complain about the shadowed template parameter. 1341 InvalidDecl = InvalidDecl 1342 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1343 // Just pretend that we didn't see the previous declaration. 1344 PrevDecl = 0; 1345 } 1346 1347 // In C++, the previous declaration we find might be a tag type 1348 // (class or enum). In this case, the new declaration will hide the 1349 // tag type. Note that this does does not apply if we're declaring a 1350 // typedef (C++ [dcl.typedef]p4). 1351 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1352 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1353 PrevDecl = 0; 1354 1355 bool Redeclaration = false; 1356 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1357 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1358 InvalidDecl, Redeclaration); 1359 } else if (R->isFunctionType()) { 1360 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1361 IsFunctionDefinition, InvalidDecl, 1362 Redeclaration); 1363 } else { 1364 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1365 InvalidDecl, Redeclaration); 1366 } 1367 1368 if (New == 0) 1369 return 0; 1370 1371 // If this has an identifier and is not an invalid redeclaration, 1372 // add it to the scope stack. 1373 if (Name && !(Redeclaration && InvalidDecl)) 1374 PushOnScopeChains(New, S); 1375 // If any semantic error occurred, mark the decl as invalid. 1376 if (D.getInvalidType() || InvalidDecl) 1377 New->setInvalidDecl(); 1378 1379 return New; 1380} 1381 1382/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1383/// types into constant array types in certain situations which would otherwise 1384/// be errors (for GCC compatibility). 1385static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1386 ASTContext &Context, 1387 bool &SizeIsNegative) { 1388 // This method tries to turn a variable array into a constant 1389 // array even when the size isn't an ICE. This is necessary 1390 // for compatibility with code that depends on gcc's buggy 1391 // constant expression folding, like struct {char x[(int)(char*)2];} 1392 SizeIsNegative = false; 1393 1394 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1395 QualType Pointee = PTy->getPointeeType(); 1396 QualType FixedType = 1397 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1398 if (FixedType.isNull()) return FixedType; 1399 FixedType = Context.getPointerType(FixedType); 1400 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1401 return FixedType; 1402 } 1403 1404 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1405 if (!VLATy) 1406 return QualType(); 1407 // FIXME: We should probably handle this case 1408 if (VLATy->getElementType()->isVariablyModifiedType()) 1409 return QualType(); 1410 1411 Expr::EvalResult EvalResult; 1412 if (!VLATy->getSizeExpr() || 1413 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1414 !EvalResult.Val.isInt()) 1415 return QualType(); 1416 1417 llvm::APSInt &Res = EvalResult.Val.getInt(); 1418 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1419 return Context.getConstantArrayType(VLATy->getElementType(), 1420 Res, ArrayType::Normal, 0); 1421 1422 SizeIsNegative = true; 1423 return QualType(); 1424} 1425 1426/// \brief Register the given locally-scoped external C declaration so 1427/// that it can be found later for redeclarations 1428void 1429Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1430 Scope *S) { 1431 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1432 "Decl is not a locally-scoped decl!"); 1433 // Note that we have a locally-scoped external with this name. 1434 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1435 1436 if (!PrevDecl) 1437 return; 1438 1439 // If there was a previous declaration of this variable, it may be 1440 // in our identifier chain. Update the identifier chain with the new 1441 // declaration. 1442 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1443 // The previous declaration was found on the identifer resolver 1444 // chain, so remove it from its scope. 1445 while (S && !S->isDeclScope(PrevDecl)) 1446 S = S->getParent(); 1447 1448 if (S) 1449 S->RemoveDecl(PrevDecl); 1450 } 1451} 1452 1453NamedDecl* 1454Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1455 QualType R, Decl* LastDeclarator, 1456 Decl* PrevDecl, bool& InvalidDecl, 1457 bool &Redeclaration) { 1458 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1459 if (D.getCXXScopeSpec().isSet()) { 1460 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1461 << D.getCXXScopeSpec().getRange(); 1462 InvalidDecl = true; 1463 // Pretend we didn't see the scope specifier. 1464 DC = 0; 1465 } 1466 1467 if (getLangOptions().CPlusPlus) { 1468 // Check that there are no default arguments (C++ only). 1469 CheckExtraCXXDefaultArguments(D); 1470 1471 if (D.getDeclSpec().isVirtualSpecified()) 1472 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1473 diag::err_virtual_non_function); 1474 } 1475 1476 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1477 if (!NewTD) return 0; 1478 1479 // Handle attributes prior to checking for duplicates in MergeVarDecl 1480 ProcessDeclAttributes(NewTD, D); 1481 // Merge the decl with the existing one if appropriate. If the decl is 1482 // in an outer scope, it isn't the same thing. 1483 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1484 Redeclaration = true; 1485 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1486 InvalidDecl = true; 1487 } 1488 1489 if (S->getFnParent() == 0) { 1490 QualType T = NewTD->getUnderlyingType(); 1491 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1492 // then it shall have block scope. 1493 if (T->isVariablyModifiedType()) { 1494 bool SizeIsNegative; 1495 QualType FixedTy = 1496 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1497 if (!FixedTy.isNull()) { 1498 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1499 NewTD->setUnderlyingType(FixedTy); 1500 } else { 1501 if (SizeIsNegative) 1502 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1503 else if (T->isVariableArrayType()) 1504 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1505 else 1506 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1507 InvalidDecl = true; 1508 } 1509 } 1510 } 1511 return NewTD; 1512} 1513 1514/// \brief Determines whether the given declaration is an out-of-scope 1515/// previous declaration. 1516/// 1517/// This routine should be invoked when name lookup has found a 1518/// previous declaration (PrevDecl) that is not in the scope where a 1519/// new declaration by the same name is being introduced. If the new 1520/// declaration occurs in a local scope, previous declarations with 1521/// linkage may still be considered previous declarations (C99 1522/// 6.2.2p4-5, C++ [basic.link]p6). 1523/// 1524/// \param PrevDecl the previous declaration found by name 1525/// lookup 1526/// 1527/// \param DC the context in which the new declaration is being 1528/// declared. 1529/// 1530/// \returns true if PrevDecl is an out-of-scope previous declaration 1531/// for a new delcaration with the same name. 1532static bool 1533isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1534 ASTContext &Context) { 1535 if (!PrevDecl) 1536 return 0; 1537 1538 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1539 // case we need to check each of the overloaded functions. 1540 if (!PrevDecl->hasLinkage()) 1541 return false; 1542 1543 if (Context.getLangOptions().CPlusPlus) { 1544 // C++ [basic.link]p6: 1545 // If there is a visible declaration of an entity with linkage 1546 // having the same name and type, ignoring entities declared 1547 // outside the innermost enclosing namespace scope, the block 1548 // scope declaration declares that same entity and receives the 1549 // linkage of the previous declaration. 1550 DeclContext *OuterContext = DC->getLookupContext(); 1551 if (!OuterContext->isFunctionOrMethod()) 1552 // This rule only applies to block-scope declarations. 1553 return false; 1554 else { 1555 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1556 if (PrevOuterContext->isRecord()) 1557 // We found a member function: ignore it. 1558 return false; 1559 else { 1560 // Find the innermost enclosing namespace for the new and 1561 // previous declarations. 1562 while (!OuterContext->isFileContext()) 1563 OuterContext = OuterContext->getParent(); 1564 while (!PrevOuterContext->isFileContext()) 1565 PrevOuterContext = PrevOuterContext->getParent(); 1566 1567 // The previous declaration is in a different namespace, so it 1568 // isn't the same function. 1569 if (OuterContext->getPrimaryContext() != 1570 PrevOuterContext->getPrimaryContext()) 1571 return false; 1572 } 1573 } 1574 } 1575 1576 return true; 1577} 1578 1579NamedDecl* 1580Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1581 QualType R, Decl* LastDeclarator, 1582 NamedDecl* PrevDecl, bool& InvalidDecl, 1583 bool &Redeclaration) { 1584 DeclarationName Name = GetNameForDeclarator(D); 1585 1586 // Check that there are no default arguments (C++ only). 1587 if (getLangOptions().CPlusPlus) 1588 CheckExtraCXXDefaultArguments(D); 1589 1590 if (R.getTypePtr()->isObjCInterfaceType()) { 1591 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object); 1592 InvalidDecl = true; 1593 } 1594 1595 VarDecl *NewVD; 1596 VarDecl::StorageClass SC; 1597 switch (D.getDeclSpec().getStorageClassSpec()) { 1598 default: assert(0 && "Unknown storage class!"); 1599 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1600 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1601 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1602 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1603 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1604 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1605 case DeclSpec::SCS_mutable: 1606 // mutable can only appear on non-static class members, so it's always 1607 // an error here 1608 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1609 InvalidDecl = true; 1610 SC = VarDecl::None; 1611 break; 1612 } 1613 1614 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1615 if (!II) { 1616 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1617 << Name.getAsString(); 1618 return 0; 1619 } 1620 1621 if (D.getDeclSpec().isVirtualSpecified()) 1622 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1623 diag::err_virtual_non_function); 1624 1625 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1626 if (!DC->isRecord() && S->getFnParent() == 0) { 1627 // C99 6.9p2: The storage-class specifiers auto and register shall not 1628 // appear in the declaration specifiers in an external declaration. 1629 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1630 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1631 InvalidDecl = true; 1632 } 1633 } 1634 if (DC->isRecord() && !CurContext->isRecord()) { 1635 // This is an out-of-line definition of a static data member. 1636 if (SC == VarDecl::Static) { 1637 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1638 diag::err_static_out_of_line) 1639 << CodeModificationHint::CreateRemoval( 1640 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1641 } else if (SC == VarDecl::None) 1642 SC = VarDecl::Static; 1643 } 1644 1645 // The variable can not have an abstract class type. 1646 if (RequireNonAbstractType(D.getIdentifierLoc(), R, 1647 diag::err_abstract_type_in_decl, 1648 AbstractVariableType)) 1649 InvalidDecl = true; 1650 1651 // The variable can not 1652 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1653 II, R, SC, 1654 // FIXME: Move to DeclGroup... 1655 D.getDeclSpec().getSourceRange().getBegin()); 1656 NewVD->setThreadSpecified(ThreadSpecified); 1657 NewVD->setNextDeclarator(LastDeclarator); 1658 1659 // Set the lexical context. If the declarator has a C++ scope specifier, the 1660 // lexical context will be different from the semantic context. 1661 NewVD->setLexicalDeclContext(CurContext); 1662 1663 // Handle attributes prior to checking for duplicates in MergeVarDecl 1664 ProcessDeclAttributes(NewVD, D); 1665 1666 // Handle GNU asm-label extension (encoded as an attribute). 1667 if (Expr *E = (Expr*) D.getAsmLabel()) { 1668 // The parser guarantees this is a string. 1669 StringLiteral *SE = cast<StringLiteral>(E); 1670 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1671 SE->getByteLength()))); 1672 } 1673 1674 // Emit an error if an address space was applied to decl with local storage. 1675 // This includes arrays of objects with address space qualifiers, but not 1676 // automatic variables that point to other address spaces. 1677 // ISO/IEC TR 18037 S5.1.2 1678 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1679 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1680 InvalidDecl = true; 1681 } 1682 1683 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1684 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1685 } 1686 1687 bool isIllegalVLA = R->isVariableArrayType() && NewVD->hasGlobalStorage(); 1688 bool isIllegalVM = R->isVariablyModifiedType() && NewVD->hasLinkage(); 1689 if (isIllegalVLA || isIllegalVM) { 1690 bool SizeIsNegative; 1691 QualType FixedTy = 1692 TryToFixInvalidVariablyModifiedType(R, Context, SizeIsNegative); 1693 if (!FixedTy.isNull()) { 1694 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1695 NewVD->setType(FixedTy); 1696 } else if (R->isVariableArrayType()) { 1697 NewVD->setInvalidDecl(); 1698 1699 const VariableArrayType *VAT = Context.getAsVariableArrayType(R); 1700 // FIXME: This won't give the correct result for 1701 // int a[10][n]; 1702 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1703 1704 if (NewVD->isFileVarDecl()) 1705 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1706 << SizeRange; 1707 else if (NewVD->getStorageClass() == VarDecl::Static) 1708 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1709 << SizeRange; 1710 else 1711 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1712 << SizeRange; 1713 } else { 1714 InvalidDecl = true; 1715 1716 if (NewVD->isFileVarDecl()) 1717 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1718 else 1719 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1720 } 1721 } 1722 1723 // If name lookup finds a previous declaration that is not in the 1724 // same scope as the new declaration, this may still be an 1725 // acceptable redeclaration. 1726 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1727 !(NewVD->hasLinkage() && 1728 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1729 PrevDecl = 0; 1730 1731 if (!PrevDecl && NewVD->isExternC(Context)) { 1732 // Since we did not find anything by this name and we're declaring 1733 // an extern "C" variable, look for a non-visible extern "C" 1734 // declaration with the same name. 1735 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1736 = LocallyScopedExternalDecls.find(Name); 1737 if (Pos != LocallyScopedExternalDecls.end()) 1738 PrevDecl = Pos->second; 1739 } 1740 1741 // Merge the decl with the existing one if appropriate. 1742 if (PrevDecl) { 1743 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1744 // The user tried to define a non-static data member 1745 // out-of-line (C++ [dcl.meaning]p1). 1746 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1747 << D.getCXXScopeSpec().getRange(); 1748 NewVD->Destroy(Context); 1749 return 0; 1750 } 1751 1752 Redeclaration = true; 1753 if (MergeVarDecl(NewVD, PrevDecl)) 1754 InvalidDecl = true; 1755 } else if (D.getCXXScopeSpec().isSet()) { 1756 // No previous declaration in the qualifying scope. 1757 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1758 << Name << D.getCXXScopeSpec().getRange(); 1759 InvalidDecl = true; 1760 } 1761 1762 if (!InvalidDecl && R->isVoidType() && !NewVD->hasExternalStorage()) { 1763 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1764 << R; 1765 InvalidDecl = true; 1766 } 1767 1768 1769 // If this is a locally-scoped extern C variable, update the map of 1770 // such variables. 1771 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1772 !InvalidDecl) 1773 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1774 1775 return NewVD; 1776} 1777 1778NamedDecl* 1779Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1780 QualType R, Decl *LastDeclarator, 1781 NamedDecl* PrevDecl, bool IsFunctionDefinition, 1782 bool& InvalidDecl, bool &Redeclaration) { 1783 assert(R.getTypePtr()->isFunctionType()); 1784 1785 DeclarationName Name = GetNameForDeclarator(D); 1786 FunctionDecl::StorageClass SC = FunctionDecl::None; 1787 switch (D.getDeclSpec().getStorageClassSpec()) { 1788 default: assert(0 && "Unknown storage class!"); 1789 case DeclSpec::SCS_auto: 1790 case DeclSpec::SCS_register: 1791 case DeclSpec::SCS_mutable: 1792 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1793 diag::err_typecheck_sclass_func); 1794 InvalidDecl = true; 1795 break; 1796 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1797 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1798 case DeclSpec::SCS_static: { 1799 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1800 // C99 6.7.1p5: 1801 // The declaration of an identifier for a function that has 1802 // block scope shall have no explicit storage-class specifier 1803 // other than extern 1804 // See also (C++ [dcl.stc]p4). 1805 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1806 diag::err_static_block_func); 1807 SC = FunctionDecl::None; 1808 } else 1809 SC = FunctionDecl::Static; 1810 break; 1811 } 1812 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1813 } 1814 1815 bool isInline = D.getDeclSpec().isInlineSpecified(); 1816 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1817 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1818 1819 // Check that the return type is not an abstract class type. 1820 // For record types, this is done by the AbstractClassUsageDiagnoser once 1821 // the class has been completely parsed. 1822 if (!DC->isRecord() && 1823 RequireNonAbstractType(D.getIdentifierLoc(), 1824 R->getAsFunctionType()->getResultType(), 1825 diag::err_abstract_type_in_decl, 1826 AbstractReturnType)) 1827 InvalidDecl = true; 1828 1829 bool isVirtualOkay = false; 1830 FunctionDecl *NewFD; 1831 if (D.getKind() == Declarator::DK_Constructor) { 1832 // This is a C++ constructor declaration. 1833 assert(DC->isRecord() && 1834 "Constructors can only be declared in a member context"); 1835 1836 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1837 1838 // Create the new declaration 1839 NewFD = CXXConstructorDecl::Create(Context, 1840 cast<CXXRecordDecl>(DC), 1841 D.getIdentifierLoc(), Name, R, 1842 isExplicit, isInline, 1843 /*isImplicitlyDeclared=*/false); 1844 1845 if (InvalidDecl) 1846 NewFD->setInvalidDecl(); 1847 } else if (D.getKind() == Declarator::DK_Destructor) { 1848 // This is a C++ destructor declaration. 1849 if (DC->isRecord()) { 1850 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1851 1852 NewFD = CXXDestructorDecl::Create(Context, 1853 cast<CXXRecordDecl>(DC), 1854 D.getIdentifierLoc(), Name, R, 1855 isInline, 1856 /*isImplicitlyDeclared=*/false); 1857 1858 if (InvalidDecl) 1859 NewFD->setInvalidDecl(); 1860 1861 isVirtualOkay = true; 1862 } else { 1863 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1864 1865 // Create a FunctionDecl to satisfy the function definition parsing 1866 // code path. 1867 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1868 Name, R, SC, isInline, 1869 /*hasPrototype=*/true, 1870 // FIXME: Move to DeclGroup... 1871 D.getDeclSpec().getSourceRange().getBegin()); 1872 InvalidDecl = true; 1873 NewFD->setInvalidDecl(); 1874 } 1875 } else if (D.getKind() == Declarator::DK_Conversion) { 1876 if (!DC->isRecord()) { 1877 Diag(D.getIdentifierLoc(), 1878 diag::err_conv_function_not_member); 1879 return 0; 1880 } else { 1881 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1882 1883 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1884 D.getIdentifierLoc(), Name, R, 1885 isInline, isExplicit); 1886 1887 if (InvalidDecl) 1888 NewFD->setInvalidDecl(); 1889 1890 isVirtualOkay = true; 1891 } 1892 } else if (DC->isRecord()) { 1893 // This is a C++ method declaration. 1894 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1895 D.getIdentifierLoc(), Name, R, 1896 (SC == FunctionDecl::Static), isInline); 1897 1898 isVirtualOkay = (SC != FunctionDecl::Static); 1899 } else { 1900 // Determine whether the function was written with a 1901 // prototype. This true when: 1902 // - we're in C++ (where every function has a prototype), 1903 // - there is a prototype in the declarator, or 1904 // - the type R of the function is some kind of typedef or other reference 1905 // to a type name (which eventually refers to a function type). 1906 bool HasPrototype = 1907 getLangOptions().CPlusPlus || 1908 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 1909 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 1910 1911 NewFD = FunctionDecl::Create(Context, DC, 1912 D.getIdentifierLoc(), 1913 Name, R, SC, isInline, HasPrototype, 1914 // FIXME: Move to DeclGroup... 1915 D.getDeclSpec().getSourceRange().getBegin()); 1916 } 1917 NewFD->setNextDeclarator(LastDeclarator); 1918 1919 // Set the lexical context. If the declarator has a C++ 1920 // scope specifier, the lexical context will be different 1921 // from the semantic context. 1922 NewFD->setLexicalDeclContext(CurContext); 1923 1924 // C++ [dcl.fct.spec]p5: 1925 // The virtual specifier shall only be used in declarations of 1926 // nonstatic class member functions that appear within a 1927 // member-specification of a class declaration; see 10.3. 1928 // 1929 // FIXME: Checking the 'virtual' specifier is not sufficient. A 1930 // function is also virtual if it overrides an already virtual 1931 // function. This is important to do here because it's part of the 1932 // declaration. 1933 if (isVirtual && !InvalidDecl) { 1934 if (!isVirtualOkay) { 1935 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1936 diag::err_virtual_non_function); 1937 } else if (!CurContext->isRecord()) { 1938 // 'virtual' was specified outside of the class. 1939 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 1940 << CodeModificationHint::CreateRemoval( 1941 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 1942 } else { 1943 // Okay: Add virtual to the method. 1944 cast<CXXMethodDecl>(NewFD)->setVirtual(); 1945 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 1946 CurClass->setAggregate(false); 1947 CurClass->setPOD(false); 1948 CurClass->setPolymorphic(true); 1949 } 1950 } 1951 1952 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 1953 !CurContext->isRecord()) { 1954 // C++ [class.static]p1: 1955 // A data or function member of a class may be declared static 1956 // in a class definition, in which case it is a static member of 1957 // the class. 1958 1959 // Complain about the 'static' specifier if it's on an out-of-line 1960 // member function definition. 1961 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1962 diag::err_static_out_of_line) 1963 << CodeModificationHint::CreateRemoval( 1964 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1965 } 1966 1967 // Handle GNU asm-label extension (encoded as an attribute). 1968 if (Expr *E = (Expr*) D.getAsmLabel()) { 1969 // The parser guarantees this is a string. 1970 StringLiteral *SE = cast<StringLiteral>(E); 1971 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1972 SE->getByteLength()))); 1973 } 1974 1975 // Copy the parameter declarations from the declarator D to 1976 // the function declaration NewFD, if they are available. 1977 if (D.getNumTypeObjects() > 0) { 1978 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1979 1980 // Create Decl objects for each parameter, adding them to the 1981 // FunctionDecl. 1982 llvm::SmallVector<ParmVarDecl*, 16> Params; 1983 1984 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1985 // function that takes no arguments, not a function that takes a 1986 // single void argument. 1987 // We let through "const void" here because Sema::GetTypeForDeclarator 1988 // already checks for that case. 1989 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1990 FTI.ArgInfo[0].Param && 1991 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1992 // empty arg list, don't push any params. 1993 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1994 1995 // In C++, the empty parameter-type-list must be spelled "void"; a 1996 // typedef of void is not permitted. 1997 if (getLangOptions().CPlusPlus && 1998 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1999 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 2000 } 2001 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2002 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2003 ParmVarDecl *PVD = (ParmVarDecl *)FTI.ArgInfo[i].Param; 2004 Params.push_back(PVD); 2005 } 2006 } 2007 2008 NewFD->setParams(Context, &Params[0], Params.size()); 2009 } else if (R->getAsTypedefType()) { 2010 // When we're declaring a function with a typedef, as in the 2011 // following example, we'll need to synthesize (unnamed) 2012 // parameters for use in the declaration. 2013 // 2014 // @code 2015 // typedef void fn(int); 2016 // fn f; 2017 // @endcode 2018 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2019 if (!FT) { 2020 // This is a typedef of a function with no prototype, so we 2021 // don't need to do anything. 2022 } else if ((FT->getNumArgs() == 0) || 2023 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2024 FT->getArgType(0)->isVoidType())) { 2025 // This is a zero-argument function. We don't need to do anything. 2026 } else { 2027 // Synthesize a parameter for each argument type. 2028 llvm::SmallVector<ParmVarDecl*, 16> Params; 2029 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2030 ArgType != FT->arg_type_end(); ++ArgType) { 2031 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2032 SourceLocation(), 0, 2033 *ArgType, VarDecl::None, 2034 0); 2035 Param->setImplicit(); 2036 Params.push_back(Param); 2037 } 2038 2039 NewFD->setParams(Context, &Params[0], Params.size()); 2040 } 2041 } 2042 2043 // If name lookup finds a previous declaration that is not in the 2044 // same scope as the new declaration, this may still be an 2045 // acceptable redeclaration. 2046 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2047 !(NewFD->hasLinkage() && 2048 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2049 PrevDecl = 0; 2050 2051 // Perform semantic checking on the function declaration. 2052 bool OverloadableAttrRequired = false; // FIXME: HACK! 2053 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2054 /*FIXME:*/OverloadableAttrRequired)) 2055 InvalidDecl = true; 2056 2057 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2058 // An out-of-line member function declaration must also be a 2059 // definition (C++ [dcl.meaning]p1). 2060 if (!IsFunctionDefinition) { 2061 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2062 << D.getCXXScopeSpec().getRange(); 2063 InvalidDecl = true; 2064 } else if (!Redeclaration) { 2065 // The user tried to provide an out-of-line definition for a 2066 // function that is a member of a class or namespace, but there 2067 // was no such member function declared (C++ [class.mfct]p2, 2068 // C++ [namespace.memdef]p2). For example: 2069 // 2070 // class X { 2071 // void f() const; 2072 // }; 2073 // 2074 // void X::f() { } // ill-formed 2075 // 2076 // Complain about this problem, and attempt to suggest close 2077 // matches (e.g., those that differ only in cv-qualifiers and 2078 // whether the parameter types are references). 2079 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2080 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2081 InvalidDecl = true; 2082 2083 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2084 true); 2085 assert(!Prev.isAmbiguous() && 2086 "Cannot have an ambiguity in previous-declaration lookup"); 2087 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2088 Func != FuncEnd; ++Func) { 2089 if (isa<FunctionDecl>(*Func) && 2090 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2091 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2092 } 2093 2094 PrevDecl = 0; 2095 } 2096 } 2097 2098 // Handle attributes. We need to have merged decls when handling attributes 2099 // (for example to check for conflicts, etc). 2100 // FIXME: This needs to happen before we merge declarations. Then, 2101 // let attribute merging cope with attribute conflicts. 2102 ProcessDeclAttributes(NewFD, D); 2103 AddKnownFunctionAttributes(NewFD); 2104 2105 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2106 // If a function name is overloadable in C, then every function 2107 // with that name must be marked "overloadable". 2108 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2109 << Redeclaration << NewFD; 2110 if (PrevDecl) 2111 Diag(PrevDecl->getLocation(), 2112 diag::note_attribute_overloadable_prev_overload); 2113 NewFD->addAttr(::new (Context) OverloadableAttr()); 2114 } 2115 2116 // If this is a locally-scoped extern C function, update the 2117 // map of such names. 2118 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2119 && !InvalidDecl) 2120 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2121 2122 return NewFD; 2123} 2124 2125/// \brief Perform semantic checking of a new function declaration. 2126/// 2127/// Performs semantic analysis of the new function declaration 2128/// NewFD. This routine performs all semantic checking that does not 2129/// require the actual declarator involved in the declaration, and is 2130/// used both for the declaration of functions as they are parsed 2131/// (called via ActOnDeclarator) and for the declaration of functions 2132/// that have been instantiated via C++ template instantiation (called 2133/// via InstantiateDecl). 2134/// 2135/// \returns true if there was an error, false otherwise. 2136bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2137 bool &Redeclaration, 2138 bool &OverloadableAttrRequired) { 2139 bool InvalidDecl = false; 2140 2141 // Semantic checking for this function declaration (in isolation). 2142 if (getLangOptions().CPlusPlus) { 2143 // C++-specific checks. 2144 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2145 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2146 else if (isa<CXXDestructorDecl>(NewFD)) { 2147 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2148 Record->setUserDeclaredDestructor(true); 2149 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2150 // user-defined destructor. 2151 Record->setPOD(false); 2152 } else if (CXXConversionDecl *Conversion 2153 = dyn_cast<CXXConversionDecl>(NewFD)) 2154 ActOnConversionDeclarator(Conversion); 2155 2156 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2157 if (NewFD->isOverloadedOperator() && 2158 CheckOverloadedOperatorDeclaration(NewFD)) 2159 InvalidDecl = true; 2160 } 2161 2162 // Check for a previous declaration of this name. 2163 if (!PrevDecl && NewFD->isExternC(Context)) { 2164 // Since we did not find anything by this name and we're declaring 2165 // an extern "C" function, look for a non-visible extern "C" 2166 // declaration with the same name. 2167 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2168 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2169 if (Pos != LocallyScopedExternalDecls.end()) 2170 PrevDecl = Pos->second; 2171 } 2172 2173 // Merge or overload the declaration with an existing declaration of 2174 // the same name, if appropriate. 2175 if (PrevDecl) { 2176 // Determine whether NewFD is an overload of PrevDecl or 2177 // a declaration that requires merging. If it's an overload, 2178 // there's no more work to do here; we'll just add the new 2179 // function to the scope. 2180 OverloadedFunctionDecl::function_iterator MatchedDecl; 2181 2182 if (!getLangOptions().CPlusPlus && 2183 AllowOverloadingOfFunction(PrevDecl, Context)) { 2184 OverloadableAttrRequired = true; 2185 2186 // Functions marked "overloadable" must have a prototype (that 2187 // we can't get through declaration merging). 2188 if (!NewFD->getType()->getAsFunctionProtoType()) { 2189 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2190 << NewFD; 2191 InvalidDecl = true; 2192 Redeclaration = true; 2193 2194 // Turn this into a variadic function with no parameters. 2195 QualType R = Context.getFunctionType( 2196 NewFD->getType()->getAsFunctionType()->getResultType(), 2197 0, 0, true, 0); 2198 NewFD->setType(R); 2199 } 2200 } 2201 2202 if (PrevDecl && 2203 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2204 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2205 Redeclaration = true; 2206 Decl *OldDecl = PrevDecl; 2207 2208 // If PrevDecl was an overloaded function, extract the 2209 // FunctionDecl that matched. 2210 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2211 OldDecl = *MatchedDecl; 2212 2213 // NewFD and OldDecl represent declarations that need to be 2214 // merged. 2215 if (MergeFunctionDecl(NewFD, OldDecl)) 2216 InvalidDecl = true; 2217 2218 if (!InvalidDecl) 2219 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2220 } 2221 } 2222 2223 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2224 // In C++, check default arguments now that we have merged decls. Unless 2225 // the lexical context is the class, because in this case this is done 2226 // during delayed parsing anyway. 2227 CheckCXXDefaultArguments(NewFD); 2228 } 2229 2230 return InvalidDecl || NewFD->isInvalidDecl(); 2231} 2232 2233bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2234 // FIXME: Need strict checking. In C89, we need to check for 2235 // any assignment, increment, decrement, function-calls, or 2236 // commas outside of a sizeof. In C99, it's the same list, 2237 // except that the aforementioned are allowed in unevaluated 2238 // expressions. Everything else falls under the 2239 // "may accept other forms of constant expressions" exception. 2240 // (We never end up here for C++, so the constant expression 2241 // rules there don't matter.) 2242 if (Init->isConstantInitializer(Context)) 2243 return false; 2244 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2245 << Init->getSourceRange(); 2246 return true; 2247} 2248 2249void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2250 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2251} 2252 2253/// AddInitializerToDecl - Adds the initializer Init to the 2254/// declaration dcl. If DirectInit is true, this is C++ direct 2255/// initialization rather than copy initialization. 2256void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2257 Decl *RealDecl = static_cast<Decl *>(dcl); 2258 // If there is no declaration, there was an error parsing it. Just ignore 2259 // the initializer. 2260 if (RealDecl == 0) 2261 return; 2262 2263 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2264 // With declarators parsed the way they are, the parser cannot 2265 // distinguish between a normal initializer and a pure-specifier. 2266 // Thus this grotesque test. 2267 IntegerLiteral *IL; 2268 Expr *Init = static_cast<Expr *>(init.get()); 2269 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2270 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2271 if (Method->isVirtual()) { 2272 Method->setPure(); 2273 2274 // A class is abstract if at least one function is pure virtual. 2275 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2276 } else { 2277 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2278 << Method->getDeclName() << Init->getSourceRange(); 2279 Method->setInvalidDecl(); 2280 } 2281 } else { 2282 Diag(Method->getLocation(), diag::err_member_function_initialization) 2283 << Method->getDeclName() << Init->getSourceRange(); 2284 Method->setInvalidDecl(); 2285 } 2286 return; 2287 } 2288 2289 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2290 if (!VDecl) { 2291 if (getLangOptions().CPlusPlus && 2292 RealDecl->getLexicalDeclContext()->isRecord() && 2293 isa<NamedDecl>(RealDecl)) 2294 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2295 << cast<NamedDecl>(RealDecl)->getDeclName(); 2296 else 2297 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2298 RealDecl->setInvalidDecl(); 2299 return; 2300 } 2301 2302 const VarDecl *Def = 0; 2303 if (VDecl->getDefinition(Def)) { 2304 Diag(VDecl->getLocation(), diag::err_redefinition) 2305 << VDecl->getDeclName(); 2306 Diag(Def->getLocation(), diag::note_previous_definition); 2307 VDecl->setInvalidDecl(); 2308 return; 2309 } 2310 2311 // Take ownership of the expression, now that we're sure we have somewhere 2312 // to put it. 2313 Expr *Init = static_cast<Expr *>(init.release()); 2314 assert(Init && "missing initializer"); 2315 2316 // Get the decls type and save a reference for later, since 2317 // CheckInitializerTypes may change it. 2318 QualType DclT = VDecl->getType(), SavT = DclT; 2319 if (VDecl->isBlockVarDecl()) { 2320 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2321 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2322 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2323 VDecl->setInvalidDecl(); 2324 } else if (!VDecl->isInvalidDecl()) { 2325 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2326 VDecl->getDeclName(), DirectInit)) 2327 VDecl->setInvalidDecl(); 2328 2329 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2330 // Don't check invalid declarations to avoid emitting useless diagnostics. 2331 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2332 if (SC == VarDecl::Static) // C99 6.7.8p4. 2333 CheckForConstantInitializer(Init, DclT); 2334 } 2335 } 2336 } else if (VDecl->isStaticDataMember() && 2337 VDecl->getLexicalDeclContext()->isRecord()) { 2338 // This is an in-class initialization for a static data member, e.g., 2339 // 2340 // struct S { 2341 // static const int value = 17; 2342 // }; 2343 2344 // Attach the initializer 2345 VDecl->setInit(Init); 2346 2347 // C++ [class.mem]p4: 2348 // A member-declarator can contain a constant-initializer only 2349 // if it declares a static member (9.4) of const integral or 2350 // const enumeration type, see 9.4.2. 2351 QualType T = VDecl->getType(); 2352 if (!T->isDependentType() && 2353 (!Context.getCanonicalType(T).isConstQualified() || 2354 !T->isIntegralType())) { 2355 Diag(VDecl->getLocation(), diag::err_member_initialization) 2356 << VDecl->getDeclName() << Init->getSourceRange(); 2357 VDecl->setInvalidDecl(); 2358 } else { 2359 // C++ [class.static.data]p4: 2360 // If a static data member is of const integral or const 2361 // enumeration type, its declaration in the class definition 2362 // can specify a constant-initializer which shall be an 2363 // integral constant expression (5.19). 2364 if (!Init->isTypeDependent() && 2365 !Init->getType()->isIntegralType()) { 2366 // We have a non-dependent, non-integral or enumeration type. 2367 Diag(Init->getSourceRange().getBegin(), 2368 diag::err_in_class_initializer_non_integral_type) 2369 << Init->getType() << Init->getSourceRange(); 2370 VDecl->setInvalidDecl(); 2371 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2372 // Check whether the expression is a constant expression. 2373 llvm::APSInt Value; 2374 SourceLocation Loc; 2375 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2376 Diag(Loc, diag::err_in_class_initializer_non_constant) 2377 << Init->getSourceRange(); 2378 VDecl->setInvalidDecl(); 2379 } 2380 } 2381 } 2382 } else if (VDecl->isFileVarDecl()) { 2383 if (VDecl->getStorageClass() == VarDecl::Extern) 2384 Diag(VDecl->getLocation(), diag::warn_extern_init); 2385 if (!VDecl->isInvalidDecl()) 2386 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2387 VDecl->getDeclName(), DirectInit)) 2388 VDecl->setInvalidDecl(); 2389 2390 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2391 // Don't check invalid declarations to avoid emitting useless diagnostics. 2392 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2393 // C99 6.7.8p4. All file scoped initializers need to be constant. 2394 CheckForConstantInitializer(Init, DclT); 2395 } 2396 } 2397 // If the type changed, it means we had an incomplete type that was 2398 // completed by the initializer. For example: 2399 // int ary[] = { 1, 3, 5 }; 2400 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2401 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2402 VDecl->setType(DclT); 2403 Init->setType(DclT); 2404 } 2405 2406 // Attach the initializer to the decl. 2407 VDecl->setInit(Init); 2408 return; 2409} 2410 2411void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2412 Decl *RealDecl = static_cast<Decl *>(dcl); 2413 2414 // If there is no declaration, there was an error parsing it. Just ignore it. 2415 if (RealDecl == 0) 2416 return; 2417 2418 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2419 QualType Type = Var->getType(); 2420 // C++ [dcl.init.ref]p3: 2421 // The initializer can be omitted for a reference only in a 2422 // parameter declaration (8.3.5), in the declaration of a 2423 // function return type, in the declaration of a class member 2424 // within its class declaration (9.2), and where the extern 2425 // specifier is explicitly used. 2426 if (Type->isReferenceType() && 2427 Var->getStorageClass() != VarDecl::Extern && 2428 Var->getStorageClass() != VarDecl::PrivateExtern) { 2429 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2430 << Var->getDeclName() 2431 << SourceRange(Var->getLocation(), Var->getLocation()); 2432 Var->setInvalidDecl(); 2433 return; 2434 } 2435 2436 // C++ [dcl.init]p9: 2437 // 2438 // If no initializer is specified for an object, and the object 2439 // is of (possibly cv-qualified) non-POD class type (or array 2440 // thereof), the object shall be default-initialized; if the 2441 // object is of const-qualified type, the underlying class type 2442 // shall have a user-declared default constructor. 2443 if (getLangOptions().CPlusPlus) { 2444 QualType InitType = Type; 2445 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2446 InitType = Array->getElementType(); 2447 if (Var->getStorageClass() != VarDecl::Extern && 2448 Var->getStorageClass() != VarDecl::PrivateExtern && 2449 InitType->isRecordType()) { 2450 const CXXConstructorDecl *Constructor = 0; 2451 if (!RequireCompleteType(Var->getLocation(), InitType, 2452 diag::err_invalid_incomplete_type_use)) 2453 Constructor 2454 = PerformInitializationByConstructor(InitType, 0, 0, 2455 Var->getLocation(), 2456 SourceRange(Var->getLocation(), 2457 Var->getLocation()), 2458 Var->getDeclName(), 2459 IK_Default); 2460 if (!Constructor) 2461 Var->setInvalidDecl(); 2462 } 2463 } 2464 2465#if 0 2466 // FIXME: Temporarily disabled because we are not properly parsing 2467 // linkage specifications on declarations, e.g., 2468 // 2469 // extern "C" const CGPoint CGPointerZero; 2470 // 2471 // C++ [dcl.init]p9: 2472 // 2473 // If no initializer is specified for an object, and the 2474 // object is of (possibly cv-qualified) non-POD class type (or 2475 // array thereof), the object shall be default-initialized; if 2476 // the object is of const-qualified type, the underlying class 2477 // type shall have a user-declared default 2478 // constructor. Otherwise, if no initializer is specified for 2479 // an object, the object and its subobjects, if any, have an 2480 // indeterminate initial value; if the object or any of its 2481 // subobjects are of const-qualified type, the program is 2482 // ill-formed. 2483 // 2484 // This isn't technically an error in C, so we don't diagnose it. 2485 // 2486 // FIXME: Actually perform the POD/user-defined default 2487 // constructor check. 2488 if (getLangOptions().CPlusPlus && 2489 Context.getCanonicalType(Type).isConstQualified() && 2490 Var->getStorageClass() != VarDecl::Extern) 2491 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2492 << Var->getName() 2493 << SourceRange(Var->getLocation(), Var->getLocation()); 2494#endif 2495 } 2496} 2497 2498/// The declarators are chained together backwards, reverse the list. 2499Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2500 // Often we have single declarators, handle them quickly. 2501 Decl *Group = static_cast<Decl*>(group); 2502 if (Group == 0) 2503 return 0; 2504 2505 Decl *NewGroup = 0; 2506 if (Group->getNextDeclarator() == 0) 2507 NewGroup = Group; 2508 else { // reverse the list. 2509 while (Group) { 2510 Decl *Next = Group->getNextDeclarator(); 2511 Group->setNextDeclarator(NewGroup); 2512 NewGroup = Group; 2513 Group = Next; 2514 } 2515 } 2516 // Perform semantic analysis that depends on having fully processed both 2517 // the declarator and initializer. 2518 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2519 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2520 if (!IDecl) 2521 continue; 2522 QualType T = IDecl->getType(); 2523 2524 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2525 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2526 if (IDecl->isBlockVarDecl() && 2527 IDecl->getStorageClass() != VarDecl::Extern) { 2528 if (!IDecl->isInvalidDecl() && 2529 RequireCompleteType(IDecl->getLocation(), T, 2530 diag::err_typecheck_decl_incomplete_type)) 2531 IDecl->setInvalidDecl(); 2532 } 2533 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2534 // object that has file scope without an initializer, and without a 2535 // storage-class specifier or with the storage-class specifier "static", 2536 // constitutes a tentative definition. Note: A tentative definition with 2537 // external linkage is valid (C99 6.2.2p5). 2538 if (IDecl->isTentativeDefinition(Context)) { 2539 QualType CheckType = T; 2540 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2541 2542 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2543 if (ArrayT) { 2544 CheckType = ArrayT->getElementType(); 2545 DiagID = diag::err_illegal_decl_array_incomplete_type; 2546 } 2547 2548 if (IDecl->isInvalidDecl()) { 2549 // Do nothing with invalid declarations 2550 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2551 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2552 // C99 6.9.2p3: If the declaration of an identifier for an object is 2553 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2554 // declared type shall not be an incomplete type. 2555 IDecl->setInvalidDecl(); 2556 } 2557 } 2558 } 2559 return NewGroup; 2560} 2561 2562/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2563/// to introduce parameters into function prototype scope. 2564Sema::DeclTy * 2565Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2566 const DeclSpec &DS = D.getDeclSpec(); 2567 2568 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2569 VarDecl::StorageClass StorageClass = VarDecl::None; 2570 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2571 StorageClass = VarDecl::Register; 2572 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2573 Diag(DS.getStorageClassSpecLoc(), 2574 diag::err_invalid_storage_class_in_func_decl); 2575 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2576 } 2577 if (DS.isThreadSpecified()) { 2578 Diag(DS.getThreadSpecLoc(), 2579 diag::err_invalid_storage_class_in_func_decl); 2580 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2581 } 2582 2583 // Check that there are no default arguments inside the type of this 2584 // parameter (C++ only). 2585 if (getLangOptions().CPlusPlus) 2586 CheckExtraCXXDefaultArguments(D); 2587 2588 // In this context, we *do not* check D.getInvalidType(). If the declarator 2589 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2590 // though it will not reflect the user specified type. 2591 QualType parmDeclType = GetTypeForDeclarator(D, S); 2592 2593 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2594 2595 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2596 // Can this happen for params? We already checked that they don't conflict 2597 // among each other. Here they can only shadow globals, which is ok. 2598 IdentifierInfo *II = D.getIdentifier(); 2599 if (II) { 2600 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2601 if (PrevDecl->isTemplateParameter()) { 2602 // Maybe we will complain about the shadowed template parameter. 2603 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2604 // Just pretend that we didn't see the previous declaration. 2605 PrevDecl = 0; 2606 } else if (S->isDeclScope(PrevDecl)) { 2607 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2608 2609 // Recover by removing the name 2610 II = 0; 2611 D.SetIdentifier(0, D.getIdentifierLoc()); 2612 } 2613 } 2614 } 2615 2616 // Parameters can not be abstract class types. 2617 // For record types, this is done by the AbstractClassUsageDiagnoser once 2618 // the class has been completely parsed. 2619 if (!CurContext->isRecord() && 2620 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2621 diag::err_abstract_type_in_decl, 2622 AbstractParamType)) 2623 D.setInvalidType(true); 2624 2625 QualType T = adjustParameterType(parmDeclType); 2626 2627 ParmVarDecl *New; 2628 if (T == parmDeclType) // parameter type did not need adjustment 2629 New = ParmVarDecl::Create(Context, CurContext, 2630 D.getIdentifierLoc(), II, 2631 parmDeclType, StorageClass, 2632 0); 2633 else // keep track of both the adjusted and unadjusted types 2634 New = OriginalParmVarDecl::Create(Context, CurContext, 2635 D.getIdentifierLoc(), II, T, 2636 parmDeclType, StorageClass, 0); 2637 2638 if (D.getInvalidType()) 2639 New->setInvalidDecl(); 2640 2641 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2642 if (D.getCXXScopeSpec().isSet()) { 2643 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2644 << D.getCXXScopeSpec().getRange(); 2645 New->setInvalidDecl(); 2646 } 2647 // Parameter declarators cannot be interface types. All ObjC objects are 2648 // passed by reference. 2649 if (T->isObjCInterfaceType()) { 2650 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2651 << "passed"; 2652 New->setInvalidDecl(); 2653 } 2654 2655 // Add the parameter declaration into this scope. 2656 S->AddDecl(New); 2657 if (II) 2658 IdResolver.AddDecl(New); 2659 2660 ProcessDeclAttributes(New, D); 2661 return New; 2662 2663} 2664 2665void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2666 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2667 "Not a function declarator!"); 2668 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2669 2670 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2671 // for a K&R function. 2672 if (!FTI.hasPrototype) { 2673 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2674 if (FTI.ArgInfo[i].Param == 0) { 2675 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2676 << FTI.ArgInfo[i].Ident; 2677 // Implicitly declare the argument as type 'int' for lack of a better 2678 // type. 2679 DeclSpec DS; 2680 const char* PrevSpec; // unused 2681 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2682 PrevSpec); 2683 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2684 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2685 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2686 } 2687 } 2688 } 2689} 2690 2691Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2692 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2693 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2694 "Not a function declarator!"); 2695 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2696 2697 if (FTI.hasPrototype) { 2698 // FIXME: Diagnose arguments without names in C. 2699 } 2700 2701 Scope *ParentScope = FnBodyScope->getParent(); 2702 2703 return ActOnStartOfFunctionDef(FnBodyScope, 2704 ActOnDeclarator(ParentScope, D, 0, 2705 /*IsFunctionDefinition=*/true)); 2706} 2707 2708Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2709 Decl *decl = static_cast<Decl*>(D); 2710 FunctionDecl *FD = cast<FunctionDecl>(decl); 2711 2712 // See if this is a redefinition. 2713 const FunctionDecl *Definition; 2714 if (FD->getBody(Definition)) { 2715 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2716 Diag(Definition->getLocation(), diag::note_previous_definition); 2717 } 2718 2719 // Builtin functions cannot be defined. 2720 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2721 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2722 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2723 FD->setInvalidDecl(); 2724 } 2725 } 2726 2727 // The return type of a function definition must be complete 2728 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2729 QualType ResultType = FD->getResultType(); 2730 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2731 RequireCompleteType(FD->getLocation(), ResultType, 2732 diag::err_func_def_incomplete_result)) 2733 FD->setInvalidDecl(); 2734 2735 PushDeclContext(FnBodyScope, FD); 2736 2737 // Check the validity of our function parameters 2738 CheckParmsForFunctionDef(FD); 2739 2740 // Introduce our parameters into the function scope 2741 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2742 ParmVarDecl *Param = FD->getParamDecl(p); 2743 Param->setOwningFunction(FD); 2744 2745 // If this has an identifier, add it to the scope stack. 2746 if (Param->getIdentifier()) 2747 PushOnScopeChains(Param, FnBodyScope); 2748 } 2749 2750 // Checking attributes of current function definition 2751 // dllimport attribute. 2752 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2753 // dllimport attribute cannot be applied to definition. 2754 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2755 Diag(FD->getLocation(), 2756 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2757 << "dllimport"; 2758 FD->setInvalidDecl(); 2759 return FD; 2760 } else { 2761 // If a symbol previously declared dllimport is later defined, the 2762 // attribute is ignored in subsequent references, and a warning is 2763 // emitted. 2764 Diag(FD->getLocation(), 2765 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2766 << FD->getNameAsCString() << "dllimport"; 2767 } 2768 } 2769 return FD; 2770} 2771 2772static bool StatementCreatesScope(Stmt* S) { 2773 bool result = false; 2774 if (DeclStmt* DS = dyn_cast<DeclStmt>(S)) { 2775 for (DeclStmt::decl_iterator i = DS->decl_begin(); 2776 i != DS->decl_end(); ++i) { 2777 if (VarDecl* D = dyn_cast<VarDecl>(*i)) { 2778 result |= D->getType()->isVariablyModifiedType(); 2779 result |= !!D->getAttr<CleanupAttr>(); 2780 } else if (TypedefDecl* D = dyn_cast<TypedefDecl>(*i)) { 2781 result |= D->getUnderlyingType()->isVariablyModifiedType(); 2782 } 2783 } 2784 } 2785 2786 return result; 2787} 2788 2789void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2790 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2791 std::vector<void*>& ScopeStack, 2792 Stmt* CurStmt, 2793 Stmt* ParentCompoundStmt) { 2794 for (Stmt::child_iterator i = CurStmt->child_begin(); 2795 i != CurStmt->child_end(); ++i) { 2796 if (!*i) continue; 2797 if (StatementCreatesScope(*i)) { 2798 ScopeStack.push_back(*i); 2799 PopScopeMap[*i] = ParentCompoundStmt; 2800 } else if (isa<LabelStmt>(CurStmt)) { 2801 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2802 } 2803 if (isa<DeclStmt>(*i)) continue; 2804 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2805 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2806 *i, CurCompound); 2807 } 2808 2809 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2810 ScopeStack.pop_back(); 2811 } 2812} 2813 2814void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2815 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2816 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2817 std::vector<void*>& ScopeStack, 2818 Stmt* CurStmt) { 2819 for (Stmt::child_iterator i = CurStmt->child_begin(); 2820 i != CurStmt->child_end(); ++i) { 2821 if (!*i) continue; 2822 if (StatementCreatesScope(*i)) { 2823 ScopeStack.push_back(*i); 2824 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2825 void* LScope = LabelScopeMap[GS->getLabel()]; 2826 if (LScope) { 2827 bool foundScopeInStack = false; 2828 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2829 if (LScope == ScopeStack[i-1]) { 2830 foundScopeInStack = true; 2831 break; 2832 } 2833 } 2834 if (!foundScopeInStack) { 2835 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2836 } 2837 } 2838 } 2839 if (isa<DeclStmt>(*i)) continue; 2840 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2841 ScopeStack, *i); 2842 } 2843 2844 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2845 ScopeStack.pop_back(); 2846 } 2847} 2848 2849Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2850 Decl *dcl = static_cast<Decl *>(D); 2851 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2852 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2853 FD->setBody(cast<CompoundStmt>(Body)); 2854 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2855 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2856 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2857 MD->setBody(cast<CompoundStmt>(Body)); 2858 } else { 2859 Body->Destroy(Context); 2860 return 0; 2861 } 2862 PopDeclContext(); 2863 // Verify and clean out per-function state. 2864 2865 bool HaveLabels = !LabelMap.empty(); 2866 // Check goto/label use. 2867 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2868 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2869 // Verify that we have no forward references left. If so, there was a goto 2870 // or address of a label taken, but no definition of it. Label fwd 2871 // definitions are indicated with a null substmt. 2872 if (I->second->getSubStmt() == 0) { 2873 LabelStmt *L = I->second; 2874 // Emit error. 2875 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2876 2877 // At this point, we have gotos that use the bogus label. Stitch it into 2878 // the function body so that they aren't leaked and that the AST is well 2879 // formed. 2880 if (Body) { 2881#if 0 2882 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2883 // and the AST is malformed anyway. We should just blow away 'L'. 2884 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2885 cast<CompoundStmt>(Body)->push_back(L); 2886#else 2887 L->Destroy(Context); 2888#endif 2889 } else { 2890 // The whole function wasn't parsed correctly, just delete this. 2891 L->Destroy(Context); 2892 } 2893 } 2894 } 2895 LabelMap.clear(); 2896 2897 if (!Body) return D; 2898 2899 if (HaveLabels) { 2900 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2901 llvm::DenseMap<void*, Stmt*> PopScopeMap; 2902 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 2903 std::vector<void*> ScopeStack; 2904 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 2905 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 2906 } 2907 2908 return D; 2909} 2910 2911/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2912/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2913NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2914 IdentifierInfo &II, Scope *S) { 2915 // Before we produce a declaration for an implicitly defined 2916 // function, see whether there was a locally-scoped declaration of 2917 // this name as a function or variable. If so, use that 2918 // (non-visible) declaration, and complain about it. 2919 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2920 = LocallyScopedExternalDecls.find(&II); 2921 if (Pos != LocallyScopedExternalDecls.end()) { 2922 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 2923 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 2924 return Pos->second; 2925 } 2926 2927 // Extension in C99. Legal in C90, but warn about it. 2928 if (getLangOptions().C99) 2929 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2930 else 2931 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2932 2933 // FIXME: handle stuff like: 2934 // void foo() { extern float X(); } 2935 // void bar() { X(); } <-- implicit decl for X in another scope. 2936 2937 // Set a Declarator for the implicit definition: int foo(); 2938 const char *Dummy; 2939 DeclSpec DS; 2940 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2941 Error = Error; // Silence warning. 2942 assert(!Error && "Error setting up implicit decl!"); 2943 Declarator D(DS, Declarator::BlockContext); 2944 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 2945 0, 0, 0, Loc, D), 2946 SourceLocation()); 2947 D.SetIdentifier(&II, Loc); 2948 2949 // Insert this function into translation-unit scope. 2950 2951 DeclContext *PrevDC = CurContext; 2952 CurContext = Context.getTranslationUnitDecl(); 2953 2954 FunctionDecl *FD = 2955 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2956 FD->setImplicit(); 2957 2958 CurContext = PrevDC; 2959 2960 AddKnownFunctionAttributes(FD); 2961 2962 return FD; 2963} 2964 2965/// \brief Adds any function attributes that we know a priori based on 2966/// the declaration of this function. 2967/// 2968/// These attributes can apply both to implicitly-declared builtins 2969/// (like __builtin___printf_chk) or to library-declared functions 2970/// like NSLog or printf. 2971void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2972 if (FD->isInvalidDecl()) 2973 return; 2974 2975 // If this is a built-in function, map its builtin attributes to 2976 // actual attributes. 2977 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2978 // Handle printf-formatting attributes. 2979 unsigned FormatIdx; 2980 bool HasVAListArg; 2981 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2982 if (!FD->getAttr<FormatAttr>()) 2983 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 2984 FormatIdx + 2)); 2985 } 2986 2987 // Mark const if we don't care about errno and that is the only 2988 // thing preventing the function from being const. This allows 2989 // IRgen to use LLVM intrinsics for such functions. 2990 if (!getLangOptions().MathErrno && 2991 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 2992 if (!FD->getAttr<ConstAttr>()) 2993 FD->addAttr(::new (Context) ConstAttr()); 2994 } 2995 } 2996 2997 IdentifierInfo *Name = FD->getIdentifier(); 2998 if (!Name) 2999 return; 3000 if ((!getLangOptions().CPlusPlus && 3001 FD->getDeclContext()->isTranslationUnit()) || 3002 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3003 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3004 LinkageSpecDecl::lang_c)) { 3005 // Okay: this could be a libc/libm/Objective-C function we know 3006 // about. 3007 } else 3008 return; 3009 3010 unsigned KnownID; 3011 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3012 if (KnownFunctionIDs[KnownID] == Name) 3013 break; 3014 3015 switch (KnownID) { 3016 case id_NSLog: 3017 case id_NSLogv: 3018 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3019 // FIXME: We known better than our headers. 3020 const_cast<FormatAttr *>(Format)->setType("printf"); 3021 } else 3022 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3023 break; 3024 3025 case id_asprintf: 3026 case id_vasprintf: 3027 if (!FD->getAttr<FormatAttr>()) 3028 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3029 break; 3030 3031 default: 3032 // Unknown function or known function without any attributes to 3033 // add. Do nothing. 3034 break; 3035 } 3036} 3037 3038TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 3039 Decl *LastDeclarator) { 3040 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3041 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3042 3043 // Scope manipulation handled by caller. 3044 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3045 D.getIdentifierLoc(), 3046 D.getIdentifier(), 3047 T); 3048 3049 if (TagType *TT = dyn_cast<TagType>(T)) { 3050 TagDecl *TD = TT->getDecl(); 3051 3052 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3053 // keep track of the TypedefDecl. 3054 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3055 TD->setTypedefForAnonDecl(NewTD); 3056 } 3057 3058 NewTD->setNextDeclarator(LastDeclarator); 3059 if (D.getInvalidType()) 3060 NewTD->setInvalidDecl(); 3061 return NewTD; 3062} 3063 3064/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3065/// former case, Name will be non-null. In the later case, Name will be null. 3066/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3067/// reference/declaration/definition of a tag. 3068Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3069 SourceLocation KWLoc, const CXXScopeSpec &SS, 3070 IdentifierInfo *Name, SourceLocation NameLoc, 3071 AttributeList *Attr) { 3072 // If this is not a definition, it must have a name. 3073 assert((Name != 0 || TK == TK_Definition) && 3074 "Nameless record must be a definition!"); 3075 3076 TagDecl::TagKind Kind; 3077 switch (TagSpec) { 3078 default: assert(0 && "Unknown tag type!"); 3079 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3080 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3081 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3082 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3083 } 3084 3085 DeclContext *SearchDC = CurContext; 3086 DeclContext *DC = CurContext; 3087 NamedDecl *PrevDecl = 0; 3088 3089 bool Invalid = false; 3090 3091 if (Name && SS.isNotEmpty()) { 3092 // We have a nested-name tag ('struct foo::bar'). 3093 3094 // Check for invalid 'foo::'. 3095 if (SS.isInvalid()) { 3096 Name = 0; 3097 goto CreateNewDecl; 3098 } 3099 3100 // FIXME: RequireCompleteDeclContext(SS)? 3101 DC = computeDeclContext(SS); 3102 SearchDC = DC; 3103 // Look-up name inside 'foo::'. 3104 PrevDecl = dyn_cast_or_null<TagDecl>( 3105 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3106 3107 // A tag 'foo::bar' must already exist. 3108 if (PrevDecl == 0) { 3109 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3110 Name = 0; 3111 goto CreateNewDecl; 3112 } 3113 } else if (Name) { 3114 // If this is a named struct, check to see if there was a previous forward 3115 // declaration or definition. 3116 // FIXME: We're looking into outer scopes here, even when we 3117 // shouldn't be. Doing so can result in ambiguities that we 3118 // shouldn't be diagnosing. 3119 LookupResult R = LookupName(S, Name, LookupTagName, 3120 /*RedeclarationOnly=*/(TK != TK_Reference)); 3121 if (R.isAmbiguous()) { 3122 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3123 // FIXME: This is not best way to recover from case like: 3124 // 3125 // struct S s; 3126 // 3127 // causes needless err_ovl_no_viable_function_in_init latter. 3128 Name = 0; 3129 PrevDecl = 0; 3130 Invalid = true; 3131 } 3132 else 3133 PrevDecl = R; 3134 3135 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3136 // FIXME: This makes sure that we ignore the contexts associated 3137 // with C structs, unions, and enums when looking for a matching 3138 // tag declaration or definition. See the similar lookup tweak 3139 // in Sema::LookupName; is there a better way to deal with this? 3140 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3141 SearchDC = SearchDC->getParent(); 3142 } 3143 } 3144 3145 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3146 // Maybe we will complain about the shadowed template parameter. 3147 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3148 // Just pretend that we didn't see the previous declaration. 3149 PrevDecl = 0; 3150 } 3151 3152 if (PrevDecl) { 3153 // Check whether the previous declaration is usable. 3154 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3155 3156 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3157 // If this is a use of a previous tag, or if the tag is already declared 3158 // in the same scope (so that the definition/declaration completes or 3159 // rementions the tag), reuse the decl. 3160 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3161 // Make sure that this wasn't declared as an enum and now used as a 3162 // struct or something similar. 3163 if (PrevTagDecl->getTagKind() != Kind) { 3164 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3165 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3166 // Recover by making this an anonymous redefinition. 3167 Name = 0; 3168 PrevDecl = 0; 3169 Invalid = true; 3170 } else { 3171 // If this is a use, just return the declaration we found. 3172 3173 // FIXME: In the future, return a variant or some other clue 3174 // for the consumer of this Decl to know it doesn't own it. 3175 // For our current ASTs this shouldn't be a problem, but will 3176 // need to be changed with DeclGroups. 3177 if (TK == TK_Reference) 3178 return PrevDecl; 3179 3180 // Diagnose attempts to redefine a tag. 3181 if (TK == TK_Definition) { 3182 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3183 Diag(NameLoc, diag::err_redefinition) << Name; 3184 Diag(Def->getLocation(), diag::note_previous_definition); 3185 // If this is a redefinition, recover by making this 3186 // struct be anonymous, which will make any later 3187 // references get the previous definition. 3188 Name = 0; 3189 PrevDecl = 0; 3190 Invalid = true; 3191 } else { 3192 // If the type is currently being defined, complain 3193 // about a nested redefinition. 3194 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3195 if (Tag->isBeingDefined()) { 3196 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3197 Diag(PrevTagDecl->getLocation(), 3198 diag::note_previous_definition); 3199 Name = 0; 3200 PrevDecl = 0; 3201 Invalid = true; 3202 } 3203 } 3204 3205 // Okay, this is definition of a previously declared or referenced 3206 // tag PrevDecl. We're going to create a new Decl for it. 3207 } 3208 } 3209 // If we get here we have (another) forward declaration or we 3210 // have a definition. Just create a new decl. 3211 } else { 3212 // If we get here, this is a definition of a new tag type in a nested 3213 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3214 // new decl/type. We set PrevDecl to NULL so that the entities 3215 // have distinct types. 3216 PrevDecl = 0; 3217 } 3218 // If we get here, we're going to create a new Decl. If PrevDecl 3219 // is non-NULL, it's a definition of the tag declared by 3220 // PrevDecl. If it's NULL, we have a new definition. 3221 } else { 3222 // PrevDecl is a namespace, template, or anything else 3223 // that lives in the IDNS_Tag identifier namespace. 3224 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3225 // The tag name clashes with a namespace name, issue an error and 3226 // recover by making this tag be anonymous. 3227 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3228 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3229 Name = 0; 3230 PrevDecl = 0; 3231 Invalid = true; 3232 } else { 3233 // The existing declaration isn't relevant to us; we're in a 3234 // new scope, so clear out the previous declaration. 3235 PrevDecl = 0; 3236 } 3237 } 3238 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3239 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3240 // C.scope.pdecl]p5: 3241 // -- for an elaborated-type-specifier of the form 3242 // 3243 // class-key identifier 3244 // 3245 // if the elaborated-type-specifier is used in the 3246 // decl-specifier-seq or parameter-declaration-clause of a 3247 // function defined in namespace scope, the identifier is 3248 // declared as a class-name in the namespace that contains 3249 // the declaration; otherwise, except as a friend 3250 // declaration, the identifier is declared in the smallest 3251 // non-class, non-function-prototype scope that contains the 3252 // declaration. 3253 // 3254 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3255 // C structs and unions. 3256 // 3257 // GNU C also supports this behavior as part of its incomplete 3258 // enum types extension, while GNU C++ does not. 3259 // 3260 // Find the context where we'll be declaring the tag. 3261 // FIXME: We would like to maintain the current DeclContext as the 3262 // lexical context, 3263 while (SearchDC->isRecord()) 3264 SearchDC = SearchDC->getParent(); 3265 3266 // Find the scope where we'll be declaring the tag. 3267 while (S->isClassScope() || 3268 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3269 ((S->getFlags() & Scope::DeclScope) == 0) || 3270 (S->getEntity() && 3271 ((DeclContext *)S->getEntity())->isTransparentContext())) 3272 S = S->getParent(); 3273 } 3274 3275CreateNewDecl: 3276 3277 // If there is an identifier, use the location of the identifier as the 3278 // location of the decl, otherwise use the location of the struct/union 3279 // keyword. 3280 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3281 3282 // Otherwise, create a new declaration. If there is a previous 3283 // declaration of the same entity, the two will be linked via 3284 // PrevDecl. 3285 TagDecl *New; 3286 3287 if (Kind == TagDecl::TK_enum) { 3288 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3289 // enum X { A, B, C } D; D should chain to X. 3290 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3291 cast_or_null<EnumDecl>(PrevDecl)); 3292 // If this is an undefined enum, warn. 3293 if (TK != TK_Definition && !Invalid) { 3294 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3295 : diag::ext_forward_ref_enum; 3296 Diag(Loc, DK); 3297 } 3298 } else { 3299 // struct/union/class 3300 3301 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3302 // struct X { int A; } D; D should chain to X. 3303 if (getLangOptions().CPlusPlus) 3304 // FIXME: Look for a way to use RecordDecl for simple structs. 3305 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3306 cast_or_null<CXXRecordDecl>(PrevDecl)); 3307 else 3308 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3309 cast_or_null<RecordDecl>(PrevDecl)); 3310 } 3311 3312 if (Kind != TagDecl::TK_enum) { 3313 // Handle #pragma pack: if the #pragma pack stack has non-default 3314 // alignment, make up a packed attribute for this decl. These 3315 // attributes are checked when the ASTContext lays out the 3316 // structure. 3317 // 3318 // It is important for implementing the correct semantics that this 3319 // happen here (in act on tag decl). The #pragma pack stack is 3320 // maintained as a result of parser callbacks which can occur at 3321 // many points during the parsing of a struct declaration (because 3322 // the #pragma tokens are effectively skipped over during the 3323 // parsing of the struct). 3324 if (unsigned Alignment = getPragmaPackAlignment()) 3325 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3326 } 3327 3328 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3329 // C++ [dcl.typedef]p3: 3330 // [...] Similarly, in a given scope, a class or enumeration 3331 // shall not be declared with the same name as a typedef-name 3332 // that is declared in that scope and refers to a type other 3333 // than the class or enumeration itself. 3334 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3335 TypedefDecl *PrevTypedef = 0; 3336 if (Lookup.getKind() == LookupResult::Found) 3337 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3338 3339 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3340 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3341 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3342 Diag(Loc, diag::err_tag_definition_of_typedef) 3343 << Context.getTypeDeclType(New) 3344 << PrevTypedef->getUnderlyingType(); 3345 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3346 Invalid = true; 3347 } 3348 } 3349 3350 if (Invalid) 3351 New->setInvalidDecl(); 3352 3353 if (Attr) 3354 ProcessDeclAttributeList(New, Attr); 3355 3356 // If we're declaring or defining a tag in function prototype scope 3357 // in C, note that this type can only be used within the function. 3358 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3359 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3360 3361 // Set the lexical context. If the tag has a C++ scope specifier, the 3362 // lexical context will be different from the semantic context. 3363 New->setLexicalDeclContext(CurContext); 3364 3365 if (TK == TK_Definition) 3366 New->startDefinition(); 3367 3368 // If this has an identifier, add it to the scope stack. 3369 if (Name) { 3370 S = getNonFieldDeclScope(S); 3371 PushOnScopeChains(New, S); 3372 } else { 3373 CurContext->addDecl(New); 3374 } 3375 3376 return New; 3377} 3378 3379void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3380 AdjustDeclIfTemplate(TagD); 3381 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3382 3383 // Enter the tag context. 3384 PushDeclContext(S, Tag); 3385 3386 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3387 FieldCollector->StartClass(); 3388 3389 if (Record->getIdentifier()) { 3390 // C++ [class]p2: 3391 // [...] The class-name is also inserted into the scope of the 3392 // class itself; this is known as the injected-class-name. For 3393 // purposes of access checking, the injected-class-name is treated 3394 // as if it were a public member name. 3395 CXXRecordDecl *InjectedClassName 3396 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3397 CurContext, Record->getLocation(), 3398 Record->getIdentifier(), Record); 3399 InjectedClassName->setImplicit(); 3400 InjectedClassName->setAccess(AS_public); 3401 PushOnScopeChains(InjectedClassName, S); 3402 assert(InjectedClassName->isInjectedClassName() && 3403 "Broken injected-class-name"); 3404 } 3405 } 3406} 3407 3408void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3409 AdjustDeclIfTemplate(TagD); 3410 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3411 3412 if (isa<CXXRecordDecl>(Tag)) 3413 FieldCollector->FinishClass(); 3414 3415 // Exit this scope of this tag's definition. 3416 PopDeclContext(); 3417 3418 // Notify the consumer that we've defined a tag. 3419 Consumer.HandleTagDeclDefinition(Tag); 3420} 3421 3422bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3423 QualType FieldTy, const Expr *BitWidth) { 3424 // C99 6.7.2.1p4 - verify the field type. 3425 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3426 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3427 // Handle incomplete types with specific error. 3428 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3429 return true; 3430 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3431 << FieldName << FieldTy << BitWidth->getSourceRange(); 3432 } 3433 3434 // If the bit-width is type- or value-dependent, don't try to check 3435 // it now. 3436 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3437 return false; 3438 3439 llvm::APSInt Value; 3440 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3441 return true; 3442 3443 // Zero-width bitfield is ok for anonymous field. 3444 if (Value == 0 && FieldName) 3445 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3446 3447 if (Value.isSigned() && Value.isNegative()) 3448 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3449 << FieldName << Value.toString(10); 3450 3451 if (!FieldTy->isDependentType()) { 3452 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3453 // FIXME: We won't need the 0 size once we check that the field type is valid. 3454 if (TypeSize && Value.getZExtValue() > TypeSize) 3455 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3456 << FieldName << (unsigned)TypeSize; 3457 } 3458 3459 return false; 3460} 3461 3462/// ActOnField - Each field of a struct/union/class is passed into this in order 3463/// to create a FieldDecl object for it. 3464Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3465 SourceLocation DeclStart, 3466 Declarator &D, ExprTy *BitfieldWidth) { 3467 3468 return HandleField(S, static_cast<RecordDecl*>(TagD), DeclStart, D, 3469 static_cast<Expr*>(BitfieldWidth), 3470 AS_public); 3471} 3472 3473/// HandleField - Analyze a field of a C struct or a C++ data member. 3474/// 3475FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3476 SourceLocation DeclStart, 3477 Declarator &D, Expr *BitWidth, 3478 AccessSpecifier AS) { 3479 IdentifierInfo *II = D.getIdentifier(); 3480 SourceLocation Loc = DeclStart; 3481 if (II) Loc = D.getIdentifierLoc(); 3482 3483 QualType T = GetTypeForDeclarator(D, S); 3484 3485 if (getLangOptions().CPlusPlus) { 3486 CheckExtraCXXDefaultArguments(D); 3487 3488 if (D.getDeclSpec().isVirtualSpecified()) 3489 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3490 diag::err_virtual_non_function); 3491 } 3492 3493 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3494 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3495 PrevDecl = 0; 3496 3497 FieldDecl *NewFD 3498 = CheckFieldDecl(II, T, Record, Loc, 3499 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3500 BitWidth, AS, PrevDecl, &D); 3501 if (NewFD->isInvalidDecl() && PrevDecl) { 3502 // Don't introduce NewFD into scope; there's already something 3503 // with the same name in the same scope. 3504 } else if (II) { 3505 PushOnScopeChains(NewFD, S); 3506 } else 3507 Record->addDecl(NewFD); 3508 3509 return NewFD; 3510} 3511 3512/// \brief Build a new FieldDecl and check its well-formedness. 3513/// 3514/// This routine builds a new FieldDecl given the fields name, type, 3515/// record, etc. \p PrevDecl should refer to any previous declaration 3516/// with the same name and in the same scope as the field to be 3517/// created. 3518/// 3519/// \returns a new FieldDecl. 3520/// 3521/// \todo The Declarator argument is a hack. It will be removed once 3522FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3523 RecordDecl *Record, SourceLocation Loc, 3524 bool Mutable, Expr *BitWidth, 3525 AccessSpecifier AS, NamedDecl *PrevDecl, 3526 Declarator *D) { 3527 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3528 bool InvalidDecl = false; 3529 3530 // If we receive a broken type, recover by assuming 'int' and 3531 // marking this declaration as invalid. 3532 if (T.isNull()) { 3533 InvalidDecl = true; 3534 T = Context.IntTy; 3535 } 3536 3537 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3538 // than a variably modified type. 3539 if (T->isVariablyModifiedType()) { 3540 bool SizeIsNegative; 3541 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3542 SizeIsNegative); 3543 if (!FixedTy.isNull()) { 3544 Diag(Loc, diag::warn_illegal_constant_array_size); 3545 T = FixedTy; 3546 } else { 3547 if (SizeIsNegative) 3548 Diag(Loc, diag::err_typecheck_negative_array_size); 3549 else 3550 Diag(Loc, diag::err_typecheck_field_variable_size); 3551 T = Context.IntTy; 3552 InvalidDecl = true; 3553 } 3554 } 3555 3556 // Fields can not have abstract class types 3557 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3558 AbstractFieldType)) 3559 InvalidDecl = true; 3560 3561 // If this is declared as a bit-field, check the bit-field. 3562 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3563 InvalidDecl = true; 3564 DeleteExpr(BitWidth); 3565 BitWidth = 0; 3566 } 3567 3568 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3569 Mutable); 3570 3571 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3572 Diag(Loc, diag::err_duplicate_member) << II; 3573 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3574 NewFD->setInvalidDecl(); 3575 Record->setInvalidDecl(); 3576 } 3577 3578 if (getLangOptions().CPlusPlus && !T->isPODType()) 3579 cast<CXXRecordDecl>(Record)->setPOD(false); 3580 3581 // FIXME: We need to pass in the attributes given an AST 3582 // representation, not a parser representation. 3583 if (D) 3584 ProcessDeclAttributes(NewFD, *D); 3585 3586 if (T.isObjCGCWeak()) 3587 Diag(Loc, diag::warn_attribute_weak_on_field); 3588 3589 if (InvalidDecl) 3590 NewFD->setInvalidDecl(); 3591 3592 NewFD->setAccess(AS); 3593 3594 // C++ [dcl.init.aggr]p1: 3595 // An aggregate is an array or a class (clause 9) with [...] no 3596 // private or protected non-static data members (clause 11). 3597 // A POD must be an aggregate. 3598 if (getLangOptions().CPlusPlus && 3599 (AS == AS_private || AS == AS_protected)) { 3600 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3601 CXXRecord->setAggregate(false); 3602 CXXRecord->setPOD(false); 3603 } 3604 3605 return NewFD; 3606} 3607 3608/// TranslateIvarVisibility - Translate visibility from a token ID to an 3609/// AST enum value. 3610static ObjCIvarDecl::AccessControl 3611TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3612 switch (ivarVisibility) { 3613 default: assert(0 && "Unknown visitibility kind"); 3614 case tok::objc_private: return ObjCIvarDecl::Private; 3615 case tok::objc_public: return ObjCIvarDecl::Public; 3616 case tok::objc_protected: return ObjCIvarDecl::Protected; 3617 case tok::objc_package: return ObjCIvarDecl::Package; 3618 } 3619} 3620 3621/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3622/// in order to create an IvarDecl object for it. 3623Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3624 SourceLocation DeclStart, 3625 Declarator &D, ExprTy *BitfieldWidth, 3626 tok::ObjCKeywordKind Visibility) { 3627 3628 IdentifierInfo *II = D.getIdentifier(); 3629 Expr *BitWidth = (Expr*)BitfieldWidth; 3630 SourceLocation Loc = DeclStart; 3631 if (II) Loc = D.getIdentifierLoc(); 3632 3633 // FIXME: Unnamed fields can be handled in various different ways, for 3634 // example, unnamed unions inject all members into the struct namespace! 3635 3636 QualType T = GetTypeForDeclarator(D, S); 3637 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3638 bool InvalidDecl = false; 3639 3640 if (BitWidth) { 3641 // 6.7.2.1p3, 6.7.2.1p4 3642 if (VerifyBitField(Loc, II, T, BitWidth)) { 3643 InvalidDecl = true; 3644 DeleteExpr(BitWidth); 3645 BitWidth = 0; 3646 } 3647 } else { 3648 // Not a bitfield. 3649 3650 // validate II. 3651 3652 } 3653 3654 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3655 // than a variably modified type. 3656 if (T->isVariablyModifiedType()) { 3657 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3658 InvalidDecl = true; 3659 } 3660 3661 // Get the visibility (access control) for this ivar. 3662 ObjCIvarDecl::AccessControl ac = 3663 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3664 : ObjCIvarDecl::None; 3665 3666 // Construct the decl. 3667 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3668 (Expr *)BitfieldWidth); 3669 3670 if (II) { 3671 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3672 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3673 && !isa<TagDecl>(PrevDecl)) { 3674 Diag(Loc, diag::err_duplicate_member) << II; 3675 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3676 NewID->setInvalidDecl(); 3677 } 3678 } 3679 3680 // Process attributes attached to the ivar. 3681 ProcessDeclAttributes(NewID, D); 3682 3683 if (D.getInvalidType() || InvalidDecl) 3684 NewID->setInvalidDecl(); 3685 3686 if (II) { 3687 // FIXME: When interfaces are DeclContexts, we'll need to add 3688 // these to the interface. 3689 S->AddDecl(NewID); 3690 IdResolver.AddDecl(NewID); 3691 } 3692 3693 return NewID; 3694} 3695 3696void Sema::ActOnFields(Scope* S, 3697 SourceLocation RecLoc, DeclTy *RecDecl, 3698 DeclTy **Fields, unsigned NumFields, 3699 SourceLocation LBrac, SourceLocation RBrac, 3700 AttributeList *Attr) { 3701 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3702 assert(EnclosingDecl && "missing record or interface decl"); 3703 3704 // If the decl this is being inserted into is invalid, then it may be a 3705 // redeclaration or some other bogus case. Don't try to add fields to it. 3706 if (EnclosingDecl->isInvalidDecl()) { 3707 // FIXME: Deallocate fields? 3708 return; 3709 } 3710 3711 3712 // Verify that all the fields are okay. 3713 unsigned NumNamedMembers = 0; 3714 llvm::SmallVector<FieldDecl*, 32> RecFields; 3715 3716 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3717 for (unsigned i = 0; i != NumFields; ++i) { 3718 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3719 assert(FD && "missing field decl"); 3720 3721 // Get the type for the field. 3722 Type *FDTy = FD->getType().getTypePtr(); 3723 3724 if (!FD->isAnonymousStructOrUnion()) { 3725 // Remember all fields written by the user. 3726 RecFields.push_back(FD); 3727 } 3728 3729 // If the field is already invalid for some reason, don't emit more 3730 // diagnostics about it. 3731 if (FD->isInvalidDecl()) 3732 continue; 3733 3734 // C99 6.7.2.1p2: 3735 // A structure or union shall not contain a member with 3736 // incomplete or function type (hence, a structure shall not 3737 // contain an instance of itself, but may contain a pointer to 3738 // an instance of itself), except that the last member of a 3739 // structure with more than one named member may have incomplete 3740 // array type; such a structure (and any union containing, 3741 // possibly recursively, a member that is such a structure) 3742 // shall not be a member of a structure or an element of an 3743 // array. 3744 if (FDTy->isFunctionType()) { 3745 // Field declared as a function. 3746 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3747 << FD->getDeclName(); 3748 FD->setInvalidDecl(); 3749 EnclosingDecl->setInvalidDecl(); 3750 continue; 3751 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3752 Record && Record->isStruct()) { 3753 // Flexible array member. 3754 if (NumNamedMembers < 1) { 3755 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3756 << FD->getDeclName(); 3757 FD->setInvalidDecl(); 3758 EnclosingDecl->setInvalidDecl(); 3759 continue; 3760 } 3761 // Okay, we have a legal flexible array member at the end of the struct. 3762 if (Record) 3763 Record->setHasFlexibleArrayMember(true); 3764 } else if (!FDTy->isDependentType() && 3765 RequireCompleteType(FD->getLocation(), FD->getType(), 3766 diag::err_field_incomplete)) { 3767 // Incomplete type 3768 FD->setInvalidDecl(); 3769 EnclosingDecl->setInvalidDecl(); 3770 continue; 3771 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3772 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3773 // If this is a member of a union, then entire union becomes "flexible". 3774 if (Record && Record->isUnion()) { 3775 Record->setHasFlexibleArrayMember(true); 3776 } else { 3777 // If this is a struct/class and this is not the last element, reject 3778 // it. Note that GCC supports variable sized arrays in the middle of 3779 // structures. 3780 if (i != NumFields-1) 3781 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3782 << FD->getDeclName(); 3783 else { 3784 // We support flexible arrays at the end of structs in 3785 // other structs as an extension. 3786 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3787 << FD->getDeclName(); 3788 if (Record) 3789 Record->setHasFlexibleArrayMember(true); 3790 } 3791 } 3792 } 3793 } else if (FDTy->isObjCInterfaceType()) { 3794 /// A field cannot be an Objective-c object 3795 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3796 FD->setInvalidDecl(); 3797 EnclosingDecl->setInvalidDecl(); 3798 continue; 3799 } 3800 // Keep track of the number of named members. 3801 if (FD->getIdentifier()) 3802 ++NumNamedMembers; 3803 } 3804 3805 // Okay, we successfully defined 'Record'. 3806 if (Record) { 3807 Record->completeDefinition(Context); 3808 } else { 3809 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3810 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3811 ID->setIVarList(ClsFields, RecFields.size(), Context); 3812 ID->setLocEnd(RBrac); 3813 3814 // Must enforce the rule that ivars in the base classes may not be 3815 // duplicates. 3816 if (ID->getSuperClass()) { 3817 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3818 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3819 ObjCIvarDecl* Ivar = (*IVI); 3820 IdentifierInfo *II = Ivar->getIdentifier(); 3821 ObjCIvarDecl* prevIvar = 3822 ID->getSuperClass()->lookupInstanceVariable(II); 3823 if (prevIvar) { 3824 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3825 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3826 } 3827 } 3828 } 3829 } else if (ObjCImplementationDecl *IMPDecl = 3830 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3831 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3832 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3833 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3834 } 3835 } 3836 3837 if (Attr) 3838 ProcessDeclAttributeList(Record, Attr); 3839} 3840 3841EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3842 EnumConstantDecl *LastEnumConst, 3843 SourceLocation IdLoc, 3844 IdentifierInfo *Id, 3845 ExprArg val) { 3846 Expr *Val = (Expr *)val.get(); 3847 3848 llvm::APSInt EnumVal(32); 3849 QualType EltTy; 3850 if (Val && !Val->isTypeDependent()) { 3851 // Make sure to promote the operand type to int. 3852 UsualUnaryConversions(Val); 3853 if (Val != val.get()) { 3854 val.release(); 3855 val = Val; 3856 } 3857 3858 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3859 SourceLocation ExpLoc; 3860 if (!Val->isValueDependent() && 3861 VerifyIntegerConstantExpression(Val, &EnumVal)) { 3862 Val = 0; 3863 } else { 3864 EltTy = Val->getType(); 3865 } 3866 } 3867 3868 if (!Val) { 3869 if (LastEnumConst) { 3870 // Assign the last value + 1. 3871 EnumVal = LastEnumConst->getInitVal(); 3872 ++EnumVal; 3873 3874 // Check for overflow on increment. 3875 if (EnumVal < LastEnumConst->getInitVal()) 3876 Diag(IdLoc, diag::warn_enum_value_overflow); 3877 3878 EltTy = LastEnumConst->getType(); 3879 } else { 3880 // First value, set to zero. 3881 EltTy = Context.IntTy; 3882 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3883 } 3884 } 3885 3886 val.release(); 3887 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 3888 Val, EnumVal); 3889} 3890 3891 3892Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3893 DeclTy *lastEnumConst, 3894 SourceLocation IdLoc, IdentifierInfo *Id, 3895 SourceLocation EqualLoc, ExprTy *val) { 3896 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3897 EnumConstantDecl *LastEnumConst = 3898 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3899 Expr *Val = static_cast<Expr*>(val); 3900 3901 // The scope passed in may not be a decl scope. Zip up the scope tree until 3902 // we find one that is. 3903 S = getNonFieldDeclScope(S); 3904 3905 // Verify that there isn't already something declared with this name in this 3906 // scope. 3907 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3908 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3909 // Maybe we will complain about the shadowed template parameter. 3910 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3911 // Just pretend that we didn't see the previous declaration. 3912 PrevDecl = 0; 3913 } 3914 3915 if (PrevDecl) { 3916 // When in C++, we may get a TagDecl with the same name; in this case the 3917 // enum constant will 'hide' the tag. 3918 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3919 "Received TagDecl when not in C++!"); 3920 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3921 if (isa<EnumConstantDecl>(PrevDecl)) 3922 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3923 else 3924 Diag(IdLoc, diag::err_redefinition) << Id; 3925 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3926 if (Val) Val->Destroy(Context); 3927 return 0; 3928 } 3929 } 3930 3931 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 3932 IdLoc, Id, Owned(Val)); 3933 3934 // Register this decl in the current scope stack. 3935 if (New) 3936 PushOnScopeChains(New, S); 3937 3938 return New; 3939} 3940 3941// FIXME: For consistency with ActOnFields(), we should have the parser 3942// pass in the source location for the left/right braces. 3943void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3944 DeclTy **Elements, unsigned NumElements) { 3945 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3946 QualType EnumType = Context.getTypeDeclType(Enum); 3947 3948 // TODO: If the result value doesn't fit in an int, it must be a long or long 3949 // long value. ISO C does not support this, but GCC does as an extension, 3950 // emit a warning. 3951 unsigned IntWidth = Context.Target.getIntWidth(); 3952 3953 // Verify that all the values are okay, compute the size of the values, and 3954 // reverse the list. 3955 unsigned NumNegativeBits = 0; 3956 unsigned NumPositiveBits = 0; 3957 3958 // Keep track of whether all elements have type int. 3959 bool AllElementsInt = true; 3960 3961 for (unsigned i = 0; i != NumElements; ++i) { 3962 EnumConstantDecl *ECD = 3963 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3964 if (!ECD) continue; // Already issued a diagnostic. 3965 3966 // If the enum value doesn't fit in an int, emit an extension warning. 3967 const llvm::APSInt &InitVal = ECD->getInitVal(); 3968 assert(InitVal.getBitWidth() >= IntWidth && 3969 "Should have promoted value to int"); 3970 if (InitVal.getBitWidth() > IntWidth) { 3971 llvm::APSInt V(InitVal); 3972 V.trunc(IntWidth); 3973 V.extend(InitVal.getBitWidth()); 3974 if (V != InitVal) 3975 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3976 << InitVal.toString(10); 3977 } 3978 3979 // Keep track of the size of positive and negative values. 3980 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3981 NumPositiveBits = std::max(NumPositiveBits, 3982 (unsigned)InitVal.getActiveBits()); 3983 else 3984 NumNegativeBits = std::max(NumNegativeBits, 3985 (unsigned)InitVal.getMinSignedBits()); 3986 3987 // Keep track of whether every enum element has type int (very commmon). 3988 if (AllElementsInt) 3989 AllElementsInt = ECD->getType() == Context.IntTy; 3990 } 3991 3992 // Figure out the type that should be used for this enum. 3993 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3994 QualType BestType; 3995 unsigned BestWidth; 3996 3997 if (NumNegativeBits) { 3998 // If there is a negative value, figure out the smallest integer type (of 3999 // int/long/longlong) that fits. 4000 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4001 BestType = Context.IntTy; 4002 BestWidth = IntWidth; 4003 } else { 4004 BestWidth = Context.Target.getLongWidth(); 4005 4006 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4007 BestType = Context.LongTy; 4008 else { 4009 BestWidth = Context.Target.getLongLongWidth(); 4010 4011 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4012 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4013 BestType = Context.LongLongTy; 4014 } 4015 } 4016 } else { 4017 // If there is no negative value, figure out which of uint, ulong, ulonglong 4018 // fits. 4019 if (NumPositiveBits <= IntWidth) { 4020 BestType = Context.UnsignedIntTy; 4021 BestWidth = IntWidth; 4022 } else if (NumPositiveBits <= 4023 (BestWidth = Context.Target.getLongWidth())) { 4024 BestType = Context.UnsignedLongTy; 4025 } else { 4026 BestWidth = Context.Target.getLongLongWidth(); 4027 assert(NumPositiveBits <= BestWidth && 4028 "How could an initializer get larger than ULL?"); 4029 BestType = Context.UnsignedLongLongTy; 4030 } 4031 } 4032 4033 // Loop over all of the enumerator constants, changing their types to match 4034 // the type of the enum if needed. 4035 for (unsigned i = 0; i != NumElements; ++i) { 4036 EnumConstantDecl *ECD = 4037 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 4038 if (!ECD) continue; // Already issued a diagnostic. 4039 4040 // Standard C says the enumerators have int type, but we allow, as an 4041 // extension, the enumerators to be larger than int size. If each 4042 // enumerator value fits in an int, type it as an int, otherwise type it the 4043 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4044 // that X has type 'int', not 'unsigned'. 4045 if (ECD->getType() == Context.IntTy) { 4046 // Make sure the init value is signed. 4047 llvm::APSInt IV = ECD->getInitVal(); 4048 IV.setIsSigned(true); 4049 ECD->setInitVal(IV); 4050 4051 if (getLangOptions().CPlusPlus) 4052 // C++ [dcl.enum]p4: Following the closing brace of an 4053 // enum-specifier, each enumerator has the type of its 4054 // enumeration. 4055 ECD->setType(EnumType); 4056 continue; // Already int type. 4057 } 4058 4059 // Determine whether the value fits into an int. 4060 llvm::APSInt InitVal = ECD->getInitVal(); 4061 bool FitsInInt; 4062 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4063 FitsInInt = InitVal.getActiveBits() < IntWidth; 4064 else 4065 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4066 4067 // If it fits into an integer type, force it. Otherwise force it to match 4068 // the enum decl type. 4069 QualType NewTy; 4070 unsigned NewWidth; 4071 bool NewSign; 4072 if (FitsInInt) { 4073 NewTy = Context.IntTy; 4074 NewWidth = IntWidth; 4075 NewSign = true; 4076 } else if (ECD->getType() == BestType) { 4077 // Already the right type! 4078 if (getLangOptions().CPlusPlus) 4079 // C++ [dcl.enum]p4: Following the closing brace of an 4080 // enum-specifier, each enumerator has the type of its 4081 // enumeration. 4082 ECD->setType(EnumType); 4083 continue; 4084 } else { 4085 NewTy = BestType; 4086 NewWidth = BestWidth; 4087 NewSign = BestType->isSignedIntegerType(); 4088 } 4089 4090 // Adjust the APSInt value. 4091 InitVal.extOrTrunc(NewWidth); 4092 InitVal.setIsSigned(NewSign); 4093 ECD->setInitVal(InitVal); 4094 4095 // Adjust the Expr initializer and type. 4096 if (ECD->getInitExpr()) 4097 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4098 /*isLvalue=*/false)); 4099 if (getLangOptions().CPlusPlus) 4100 // C++ [dcl.enum]p4: Following the closing brace of an 4101 // enum-specifier, each enumerator has the type of its 4102 // enumeration. 4103 ECD->setType(EnumType); 4104 else 4105 ECD->setType(NewTy); 4106 } 4107 4108 Enum->completeDefinition(Context, BestType); 4109} 4110 4111Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4112 ExprArg expr) { 4113 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4114 4115 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 4116} 4117 4118