SemaDecl.cpp revision 465226e23a3008bd68973513dda1f9e3cd27dbdd
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 "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/DeclObjC.h" 20#include "clang/AST/DeclTemplate.h" 21#include "clang/AST/ExprCXX.h" 22#include "clang/AST/StmtCXX.h" 23#include "clang/Parse/DeclSpec.h" 24#include "clang/Basic/TargetInfo.h" 25#include "clang/Basic/SourceManager.h" 26// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 27#include "clang/Lex/Preprocessor.h" 28#include "clang/Lex/HeaderSearch.h" 29#include "llvm/ADT/SmallSet.h" 30#include "llvm/ADT/STLExtras.h" 31#include <algorithm> 32#include <functional> 33using namespace clang; 34 35/// getDeclName - Return a pretty name for the specified decl if possible, or 36/// an empty string if not. This is used for pretty crash reporting. 37std::string Sema::getDeclName(DeclPtrTy d) { 38 Decl *D = d.getAs<Decl>(); 39 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 40 return DN->getQualifiedNameAsString(); 41 return ""; 42} 43 44Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 45 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 46} 47 48/// \brief If the identifier refers to a type name within this scope, 49/// return the declaration of that type. 50/// 51/// This routine performs ordinary name lookup of the identifier II 52/// within the given scope, with optional C++ scope specifier SS, to 53/// determine whether the name refers to a type. If so, returns an 54/// opaque pointer (actually a QualType) corresponding to that 55/// type. Otherwise, returns NULL. 56/// 57/// If name lookup results in an ambiguity, this routine will complain 58/// and then return NULL. 59Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 60 Scope *S, const CXXScopeSpec *SS) { 61 // C++ [temp.res]p3: 62 // A qualified-id that refers to a type and in which the 63 // nested-name-specifier depends on a template-parameter (14.6.2) 64 // shall be prefixed by the keyword typename to indicate that the 65 // qualified-id denotes a type, forming an 66 // elaborated-type-specifier (7.1.5.3). 67 // 68 // We therefore do not perform any name lookup if the result would 69 // refer to a member of an unknown specialization. 70 if (SS && isUnknownSpecialization(*SS)) 71 return 0; 72 73 LookupResult Result 74 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 75 76 NamedDecl *IIDecl = 0; 77 switch (Result.getKind()) { 78 case LookupResult::NotFound: 79 case LookupResult::FoundOverloaded: 80 return 0; 81 82 case LookupResult::AmbiguousBaseSubobjectTypes: 83 case LookupResult::AmbiguousBaseSubobjects: 84 case LookupResult::AmbiguousReference: { 85 // Look to see if we have a type anywhere in the list of results. 86 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 87 Res != ResEnd; ++Res) { 88 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 89 if (!IIDecl || 90 (*Res)->getLocation().getRawEncoding() < 91 IIDecl->getLocation().getRawEncoding()) 92 IIDecl = *Res; 93 } 94 } 95 96 if (!IIDecl) { 97 // None of the entities we found is a type, so there is no way 98 // to even assume that the result is a type. In this case, don't 99 // complain about the ambiguity. The parser will either try to 100 // perform this lookup again (e.g., as an object name), which 101 // will produce the ambiguity, or will complain that it expected 102 // a type name. 103 Result.Destroy(); 104 return 0; 105 } 106 107 // We found a type within the ambiguous lookup; diagnose the 108 // ambiguity and then return that type. This might be the right 109 // answer, or it might not be, but it suppresses any attempt to 110 // perform the name lookup again. 111 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 112 break; 113 } 114 115 case LookupResult::Found: 116 IIDecl = Result.getAsDecl(); 117 break; 118 } 119 120 if (IIDecl) { 121 QualType T; 122 123 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 124 // Check whether we can use this type 125 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 126 127 if (getLangOptions().CPlusPlus) { 128 // C++ [temp.local]p2: 129 // Within the scope of a class template specialization or 130 // partial specialization, when the injected-class-name is 131 // not followed by a <, it is equivalent to the 132 // injected-class-name followed by the template-argument s 133 // of the class template specialization or partial 134 // specialization enclosed in <>. 135 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 136 if (RD->isInjectedClassName()) 137 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 138 T = Template->getInjectedClassNameType(Context); 139 } 140 141 if (T.isNull()) 142 T = Context.getTypeDeclType(TD); 143 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 144 // Check whether we can use this interface. 145 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 146 147 T = Context.getObjCInterfaceType(IDecl); 148 } else 149 return 0; 150 151 if (SS) 152 T = getQualifiedNameType(*SS, T); 153 154 return T.getAsOpaquePtr(); 155 } 156 157 return 0; 158} 159 160/// isTagName() - This method is called *for error recovery purposes only* 161/// to determine if the specified name is a valid tag name ("struct foo"). If 162/// so, this returns the TST for the tag corresponding to it (TST_enum, 163/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 164/// where the user forgot to specify the tag. 165DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 166 // Do a tag name lookup in this scope. 167 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 168 if (R.getKind() == LookupResult::Found) 169 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 170 switch (TD->getTagKind()) { 171 case TagDecl::TK_struct: return DeclSpec::TST_struct; 172 case TagDecl::TK_union: return DeclSpec::TST_union; 173 case TagDecl::TK_class: return DeclSpec::TST_class; 174 case TagDecl::TK_enum: return DeclSpec::TST_enum; 175 } 176 } 177 178 return DeclSpec::TST_unspecified; 179} 180 181 182 183DeclContext *Sema::getContainingDC(DeclContext *DC) { 184 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 185 // A C++ out-of-line method will return to the file declaration context. 186 if (MD->isOutOfLineDefinition()) 187 return MD->getLexicalDeclContext(); 188 189 // A C++ inline method is parsed *after* the topmost class it was declared 190 // in is fully parsed (it's "complete"). 191 // The parsing of a C++ inline method happens at the declaration context of 192 // the topmost (non-nested) class it is lexically declared in. 193 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 194 DC = MD->getParent(); 195 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 196 DC = RD; 197 198 // Return the declaration context of the topmost class the inline method is 199 // declared in. 200 return DC; 201 } 202 203 if (isa<ObjCMethodDecl>(DC)) 204 return Context.getTranslationUnitDecl(); 205 206 return DC->getLexicalParent(); 207} 208 209void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 210 assert(getContainingDC(DC) == CurContext && 211 "The next DeclContext should be lexically contained in the current one."); 212 CurContext = DC; 213 S->setEntity(DC); 214} 215 216void Sema::PopDeclContext() { 217 assert(CurContext && "DeclContext imbalance!"); 218 219 CurContext = getContainingDC(CurContext); 220} 221 222/// \brief Determine whether we allow overloading of the function 223/// PrevDecl with another declaration. 224/// 225/// This routine determines whether overloading is possible, not 226/// whether some new function is actually an overload. It will return 227/// true in C++ (where we can always provide overloads) or, as an 228/// extension, in C when the previous function is already an 229/// overloaded function declaration or has the "overloadable" 230/// attribute. 231static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 232 if (Context.getLangOptions().CPlusPlus) 233 return true; 234 235 if (isa<OverloadedFunctionDecl>(PrevDecl)) 236 return true; 237 238 return PrevDecl->getAttr<OverloadableAttr>() != 0; 239} 240 241/// Add this decl to the scope shadowed decl chains. 242void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 243 // Move up the scope chain until we find the nearest enclosing 244 // non-transparent context. The declaration will be introduced into this 245 // scope. 246 while (S->getEntity() && 247 ((DeclContext *)S->getEntity())->isTransparentContext()) 248 S = S->getParent(); 249 250 S->AddDecl(DeclPtrTy::make(D)); 251 252 // Add scoped declarations into their context, so that they can be 253 // found later. Declarations without a context won't be inserted 254 // into any context. 255 CurContext->addDecl(Context, D); 256 257 // C++ [basic.scope]p4: 258 // -- exactly one declaration shall declare a class name or 259 // enumeration name that is not a typedef name and the other 260 // declarations shall all refer to the same object or 261 // enumerator, or all refer to functions and function templates; 262 // in this case the class name or enumeration name is hidden. 263 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 264 // We are pushing the name of a tag (enum or class). 265 if (CurContext->getLookupContext() 266 == TD->getDeclContext()->getLookupContext()) { 267 // We're pushing the tag into the current context, which might 268 // require some reshuffling in the identifier resolver. 269 IdentifierResolver::iterator 270 I = IdResolver.begin(TD->getDeclName()), 271 IEnd = IdResolver.end(); 272 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 273 NamedDecl *PrevDecl = *I; 274 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 275 PrevDecl = *I, ++I) { 276 if (TD->declarationReplaces(*I)) { 277 // This is a redeclaration. Remove it from the chain and 278 // break out, so that we'll add in the shadowed 279 // declaration. 280 S->RemoveDecl(DeclPtrTy::make(*I)); 281 if (PrevDecl == *I) { 282 IdResolver.RemoveDecl(*I); 283 IdResolver.AddDecl(TD); 284 return; 285 } else { 286 IdResolver.RemoveDecl(*I); 287 break; 288 } 289 } 290 } 291 292 // There is already a declaration with the same name in the same 293 // scope, which is not a tag declaration. It must be found 294 // before we find the new declaration, so insert the new 295 // declaration at the end of the chain. 296 IdResolver.AddShadowedDecl(TD, PrevDecl); 297 298 return; 299 } 300 } 301 } else if (isa<FunctionDecl>(D) && 302 AllowOverloadingOfFunction(D, Context)) { 303 // We are pushing the name of a function, which might be an 304 // overloaded name. 305 FunctionDecl *FD = cast<FunctionDecl>(D); 306 IdentifierResolver::iterator Redecl 307 = std::find_if(IdResolver.begin(FD->getDeclName()), 308 IdResolver.end(), 309 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 310 FD)); 311 if (Redecl != IdResolver.end() && 312 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 313 // There is already a declaration of a function on our 314 // IdResolver chain. Replace it with this declaration. 315 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 316 IdResolver.RemoveDecl(*Redecl); 317 } 318 } else if (isa<ObjCInterfaceDecl>(D)) { 319 // We're pushing an Objective-C interface into the current 320 // context. If there is already an alias declaration, remove it first. 321 for (IdentifierResolver::iterator 322 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 323 I != IEnd; ++I) { 324 if (isa<ObjCCompatibleAliasDecl>(*I)) { 325 S->RemoveDecl(DeclPtrTy::make(*I)); 326 IdResolver.RemoveDecl(*I); 327 break; 328 } 329 } 330 } 331 332 IdResolver.AddDecl(D); 333} 334 335void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 336 if (S->decl_empty()) return; 337 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 338 "Scope shouldn't contain decls!"); 339 340 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 341 I != E; ++I) { 342 Decl *TmpD = (*I).getAs<Decl>(); 343 assert(TmpD && "This decl didn't get pushed??"); 344 345 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 346 NamedDecl *D = cast<NamedDecl>(TmpD); 347 348 if (!D->getDeclName()) continue; 349 350 // Remove this name from our lexical scope. 351 IdResolver.RemoveDecl(D); 352 } 353} 354 355/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 356/// return 0 if one not found. 357ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 358 // The third "scope" argument is 0 since we aren't enabling lazy built-in 359 // creation from this context. 360 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 361 362 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 363} 364 365/// getNonFieldDeclScope - Retrieves the innermost scope, starting 366/// from S, where a non-field would be declared. This routine copes 367/// with the difference between C and C++ scoping rules in structs and 368/// unions. For example, the following code is well-formed in C but 369/// ill-formed in C++: 370/// @code 371/// struct S6 { 372/// enum { BAR } e; 373/// }; 374/// 375/// void test_S6() { 376/// struct S6 a; 377/// a.e = BAR; 378/// } 379/// @endcode 380/// For the declaration of BAR, this routine will return a different 381/// scope. The scope S will be the scope of the unnamed enumeration 382/// within S6. In C++, this routine will return the scope associated 383/// with S6, because the enumeration's scope is a transparent 384/// context but structures can contain non-field names. In C, this 385/// routine will return the translation unit scope, since the 386/// enumeration's scope is a transparent context and structures cannot 387/// contain non-field names. 388Scope *Sema::getNonFieldDeclScope(Scope *S) { 389 while (((S->getFlags() & Scope::DeclScope) == 0) || 390 (S->getEntity() && 391 ((DeclContext *)S->getEntity())->isTransparentContext()) || 392 (S->isClassScope() && !getLangOptions().CPlusPlus)) 393 S = S->getParent(); 394 return S; 395} 396 397void Sema::InitBuiltinVaListType() { 398 if (!Context.getBuiltinVaListType().isNull()) 399 return; 400 401 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 402 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 403 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 404 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 405} 406 407/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 408/// file scope. lazily create a decl for it. ForRedeclaration is true 409/// if we're creating this built-in in anticipation of redeclaring the 410/// built-in. 411NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 412 Scope *S, bool ForRedeclaration, 413 SourceLocation Loc) { 414 Builtin::ID BID = (Builtin::ID)bid; 415 416 if (Context.BuiltinInfo.hasVAListUse(BID)) 417 InitBuiltinVaListType(); 418 419 Builtin::Context::GetBuiltinTypeError Error; 420 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 421 switch (Error) { 422 case Builtin::Context::GE_None: 423 // Okay 424 break; 425 426 case Builtin::Context::GE_Missing_FILE: 427 if (ForRedeclaration) 428 Diag(Loc, diag::err_implicit_decl_requires_stdio) 429 << Context.BuiltinInfo.GetName(BID); 430 return 0; 431 } 432 433 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 434 Diag(Loc, diag::ext_implicit_lib_function_decl) 435 << Context.BuiltinInfo.GetName(BID) 436 << R; 437 if (Context.BuiltinInfo.getHeaderName(BID) && 438 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 439 != Diagnostic::Ignored) 440 Diag(Loc, diag::note_please_include_header) 441 << Context.BuiltinInfo.getHeaderName(BID) 442 << Context.BuiltinInfo.GetName(BID); 443 } 444 445 FunctionDecl *New = FunctionDecl::Create(Context, 446 Context.getTranslationUnitDecl(), 447 Loc, II, R, 448 FunctionDecl::Extern, false, 449 /*hasPrototype=*/true); 450 New->setImplicit(); 451 452 // Create Decl objects for each parameter, adding them to the 453 // FunctionDecl. 454 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 455 llvm::SmallVector<ParmVarDecl*, 16> Params; 456 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 457 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 458 FT->getArgType(i), VarDecl::None, 0)); 459 New->setParams(Context, Params.data(), Params.size()); 460 } 461 462 AddKnownFunctionAttributes(New); 463 464 // TUScope is the translation-unit scope to insert this function into. 465 // FIXME: This is hideous. We need to teach PushOnScopeChains to 466 // relate Scopes to DeclContexts, and probably eliminate CurContext 467 // entirely, but we're not there yet. 468 DeclContext *SavedContext = CurContext; 469 CurContext = Context.getTranslationUnitDecl(); 470 PushOnScopeChains(New, TUScope); 471 CurContext = SavedContext; 472 return New; 473} 474 475/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 476/// everything from the standard library is defined. 477NamespaceDecl *Sema::GetStdNamespace() { 478 if (!StdNamespace) { 479 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 480 DeclContext *Global = Context.getTranslationUnitDecl(); 481 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 482 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 483 } 484 return StdNamespace; 485} 486 487/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 488/// same name and scope as a previous declaration 'Old'. Figure out 489/// how to resolve this situation, merging decls or emitting 490/// diagnostics as appropriate. If there was an error, set New to be invalid. 491/// 492void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 493 // If either decl is known invalid already, set the new one to be invalid and 494 // don't bother doing any merging checks. 495 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 496 return New->setInvalidDecl(); 497 498 bool objc_types = false; 499 500 // Allow multiple definitions for ObjC built-in typedefs. 501 // FIXME: Verify the underlying types are equivalent! 502 if (getLangOptions().ObjC1) { 503 const IdentifierInfo *TypeID = New->getIdentifier(); 504 switch (TypeID->getLength()) { 505 default: break; 506 case 2: 507 if (!TypeID->isStr("id")) 508 break; 509 Context.setObjCIdType(Context.getTypeDeclType(New)); 510 objc_types = true; 511 break; 512 case 5: 513 if (!TypeID->isStr("Class")) 514 break; 515 Context.setObjCClassType(Context.getTypeDeclType(New)); 516 return; 517 case 3: 518 if (!TypeID->isStr("SEL")) 519 break; 520 Context.setObjCSelType(Context.getTypeDeclType(New)); 521 return; 522 case 8: 523 if (!TypeID->isStr("Protocol")) 524 break; 525 Context.setObjCProtoType(New->getUnderlyingType()); 526 return; 527 } 528 // Fall through - the typedef name was not a builtin type. 529 } 530 // Verify the old decl was also a type. 531 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 532 if (!Old) { 533 Diag(New->getLocation(), diag::err_redefinition_different_kind) 534 << New->getDeclName(); 535 if (OldD->getLocation().isValid()) 536 Diag(OldD->getLocation(), diag::note_previous_definition); 537 return New->setInvalidDecl(); 538 } 539 540 // Determine the "old" type we'll use for checking and diagnostics. 541 QualType OldType; 542 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 543 OldType = OldTypedef->getUnderlyingType(); 544 else 545 OldType = Context.getTypeDeclType(Old); 546 547 // If the typedef types are not identical, reject them in all languages and 548 // with any extensions enabled. 549 550 if (OldType != New->getUnderlyingType() && 551 Context.getCanonicalType(OldType) != 552 Context.getCanonicalType(New->getUnderlyingType())) { 553 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 554 << New->getUnderlyingType() << OldType; 555 if (Old->getLocation().isValid()) 556 Diag(Old->getLocation(), diag::note_previous_definition); 557 return New->setInvalidDecl(); 558 } 559 560 if (objc_types || getLangOptions().Microsoft) 561 return; 562 563 // C++ [dcl.typedef]p2: 564 // In a given non-class scope, a typedef specifier can be used to 565 // redefine the name of any type declared in that scope to refer 566 // to the type to which it already refers. 567 if (getLangOptions().CPlusPlus) { 568 if (!isa<CXXRecordDecl>(CurContext)) 569 return; 570 Diag(New->getLocation(), diag::err_redefinition) 571 << New->getDeclName(); 572 Diag(Old->getLocation(), diag::note_previous_definition); 573 return New->setInvalidDecl(); 574 } 575 576 // If we have a redefinition of a typedef in C, emit a warning. This warning 577 // is normally mapped to an error, but can be controlled with 578 // -Wtypedef-redefinition. If either the original was in a system header, 579 // don't emit this for compatibility with GCC. 580 if (PP.getDiagnostics().getSuppressSystemWarnings() && 581 Context.getSourceManager().isInSystemHeader(Old->getLocation())) 582 return; 583 584 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 585 << New->getDeclName(); 586 Diag(Old->getLocation(), diag::note_previous_definition); 587 return; 588} 589 590/// DeclhasAttr - returns true if decl Declaration already has the target 591/// attribute. 592static bool DeclHasAttr(const Decl *decl, const Attr *target) { 593 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 594 if (attr->getKind() == target->getKind()) 595 return true; 596 597 return false; 598} 599 600/// MergeAttributes - append attributes from the Old decl to the New one. 601static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 602 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 603 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 604 Attr *NewAttr = attr->clone(C); 605 NewAttr->setInherited(true); 606 New->addAttr(NewAttr); 607 } 608 } 609} 610 611/// Used in MergeFunctionDecl to keep track of function parameters in 612/// C. 613struct GNUCompatibleParamWarning { 614 ParmVarDecl *OldParm; 615 ParmVarDecl *NewParm; 616 QualType PromotedType; 617}; 618 619/// MergeFunctionDecl - We just parsed a function 'New' from 620/// declarator D which has the same name and scope as a previous 621/// declaration 'Old'. Figure out how to resolve this situation, 622/// merging decls or emitting diagnostics as appropriate. 623/// 624/// In C++, New and Old must be declarations that are not 625/// overloaded. Use IsOverload to determine whether New and Old are 626/// overloaded, and to select the Old declaration that New should be 627/// merged with. 628/// 629/// Returns true if there was an error, false otherwise. 630bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 631 assert(!isa<OverloadedFunctionDecl>(OldD) && 632 "Cannot merge with an overloaded function declaration"); 633 634 // Verify the old decl was also a function. 635 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 636 if (!Old) { 637 Diag(New->getLocation(), diag::err_redefinition_different_kind) 638 << New->getDeclName(); 639 Diag(OldD->getLocation(), diag::note_previous_definition); 640 return true; 641 } 642 643 // Determine whether the previous declaration was a definition, 644 // implicit declaration, or a declaration. 645 diag::kind PrevDiag; 646 if (Old->isThisDeclarationADefinition()) 647 PrevDiag = diag::note_previous_definition; 648 else if (Old->isImplicit()) 649 PrevDiag = diag::note_previous_implicit_declaration; 650 else 651 PrevDiag = diag::note_previous_declaration; 652 653 QualType OldQType = Context.getCanonicalType(Old->getType()); 654 QualType NewQType = Context.getCanonicalType(New->getType()); 655 656 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 657 New->getStorageClass() == FunctionDecl::Static && 658 Old->getStorageClass() != FunctionDecl::Static) { 659 Diag(New->getLocation(), diag::err_static_non_static) 660 << New; 661 Diag(Old->getLocation(), PrevDiag); 662 return true; 663 } 664 665 if (getLangOptions().CPlusPlus) { 666 // (C++98 13.1p2): 667 // Certain function declarations cannot be overloaded: 668 // -- Function declarations that differ only in the return type 669 // cannot be overloaded. 670 QualType OldReturnType 671 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 672 QualType NewReturnType 673 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 674 if (OldReturnType != NewReturnType) { 675 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 676 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 677 return true; 678 } 679 680 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 681 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 682 if (OldMethod && NewMethod && 683 OldMethod->getLexicalDeclContext() == 684 NewMethod->getLexicalDeclContext()) { 685 // -- Member function declarations with the same name and the 686 // same parameter types cannot be overloaded if any of them 687 // is a static member function declaration. 688 if (OldMethod->isStatic() || NewMethod->isStatic()) { 689 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 690 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 691 return true; 692 } 693 694 // C++ [class.mem]p1: 695 // [...] A member shall not be declared twice in the 696 // member-specification, except that a nested class or member 697 // class template can be declared and then later defined. 698 unsigned NewDiag; 699 if (isa<CXXConstructorDecl>(OldMethod)) 700 NewDiag = diag::err_constructor_redeclared; 701 else if (isa<CXXDestructorDecl>(NewMethod)) 702 NewDiag = diag::err_destructor_redeclared; 703 else if (isa<CXXConversionDecl>(NewMethod)) 704 NewDiag = diag::err_conv_function_redeclared; 705 else 706 NewDiag = diag::err_member_redeclared; 707 708 Diag(New->getLocation(), NewDiag); 709 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 710 } 711 712 // (C++98 8.3.5p3): 713 // All declarations for a function shall agree exactly in both the 714 // return type and the parameter-type-list. 715 if (OldQType == NewQType) 716 return MergeCompatibleFunctionDecls(New, Old); 717 718 // Fall through for conflicting redeclarations and redefinitions. 719 } 720 721 // C: Function types need to be compatible, not identical. This handles 722 // duplicate function decls like "void f(int); void f(enum X);" properly. 723 if (!getLangOptions().CPlusPlus && 724 Context.typesAreCompatible(OldQType, NewQType)) { 725 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 726 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 727 const FunctionProtoType *OldProto = 0; 728 if (isa<FunctionNoProtoType>(NewFuncType) && 729 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 730 // The old declaration provided a function prototype, but the 731 // new declaration does not. Merge in the prototype. 732 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 733 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 734 OldProto->arg_type_end()); 735 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 736 ParamTypes.data(), ParamTypes.size(), 737 OldProto->isVariadic(), 738 OldProto->getTypeQuals()); 739 New->setType(NewQType); 740 New->setHasInheritedPrototype(); 741 742 // Synthesize a parameter for each argument type. 743 llvm::SmallVector<ParmVarDecl*, 16> Params; 744 for (FunctionProtoType::arg_type_iterator 745 ParamType = OldProto->arg_type_begin(), 746 ParamEnd = OldProto->arg_type_end(); 747 ParamType != ParamEnd; ++ParamType) { 748 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 749 SourceLocation(), 0, 750 *ParamType, VarDecl::None, 751 0); 752 Param->setImplicit(); 753 Params.push_back(Param); 754 } 755 756 New->setParams(Context, Params.data(), Params.size()); 757 } 758 759 return MergeCompatibleFunctionDecls(New, Old); 760 } 761 762 // GNU C permits a K&R definition to follow a prototype declaration 763 // if the declared types of the parameters in the K&R definition 764 // match the types in the prototype declaration, even when the 765 // promoted types of the parameters from the K&R definition differ 766 // from the types in the prototype. GCC then keeps the types from 767 // the prototype. 768 if (!getLangOptions().CPlusPlus && 769 Old->hasPrototype() && !New->hasPrototype() && 770 New->getType()->getAsFunctionProtoType() && 771 Old->getNumParams() == New->getNumParams()) { 772 llvm::SmallVector<QualType, 16> ArgTypes; 773 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 774 const FunctionProtoType *OldProto 775 = Old->getType()->getAsFunctionProtoType(); 776 const FunctionProtoType *NewProto 777 = New->getType()->getAsFunctionProtoType(); 778 779 // Determine whether this is the GNU C extension. 780 bool GNUCompatible = 781 Context.typesAreCompatible(OldProto->getResultType(), 782 NewProto->getResultType()) && 783 (OldProto->isVariadic() == NewProto->isVariadic()); 784 for (unsigned Idx = 0, End = Old->getNumParams(); 785 GNUCompatible && Idx != End; ++Idx) { 786 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 787 ParmVarDecl *NewParm = New->getParamDecl(Idx); 788 if (Context.typesAreCompatible(OldParm->getType(), 789 NewProto->getArgType(Idx))) { 790 ArgTypes.push_back(NewParm->getType()); 791 } else if (Context.typesAreCompatible(OldParm->getType(), 792 NewParm->getType())) { 793 GNUCompatibleParamWarning Warn 794 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 795 Warnings.push_back(Warn); 796 ArgTypes.push_back(NewParm->getType()); 797 } else 798 GNUCompatible = false; 799 } 800 801 if (GNUCompatible) { 802 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 803 Diag(Warnings[Warn].NewParm->getLocation(), 804 diag::ext_param_promoted_not_compatible_with_prototype) 805 << Warnings[Warn].PromotedType 806 << Warnings[Warn].OldParm->getType(); 807 Diag(Warnings[Warn].OldParm->getLocation(), 808 diag::note_previous_declaration); 809 } 810 811 New->setType(Context.getFunctionType(NewProto->getResultType(), 812 &ArgTypes[0], ArgTypes.size(), 813 NewProto->isVariadic(), 814 NewProto->getTypeQuals())); 815 return MergeCompatibleFunctionDecls(New, Old); 816 } 817 818 // Fall through to diagnose conflicting types. 819 } 820 821 // A function that has already been declared has been redeclared or defined 822 // with a different type- show appropriate diagnostic 823 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 824 // The user has declared a builtin function with an incompatible 825 // signature. 826 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 827 // The function the user is redeclaring is a library-defined 828 // function like 'malloc' or 'printf'. Warn about the 829 // redeclaration, then pretend that we don't know about this 830 // library built-in. 831 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 832 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 833 << Old << Old->getType(); 834 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 835 Old->setInvalidDecl(); 836 return false; 837 } 838 839 PrevDiag = diag::note_previous_builtin_declaration; 840 } 841 842 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 843 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 844 return true; 845} 846 847/// \brief Completes the merge of two function declarations that are 848/// known to be compatible. 849/// 850/// This routine handles the merging of attributes and other 851/// properties of function declarations form the old declaration to 852/// the new declaration, once we know that New is in fact a 853/// redeclaration of Old. 854/// 855/// \returns false 856bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 857 // Merge the attributes 858 MergeAttributes(New, Old, Context); 859 860 // Merge the storage class. 861 if (Old->getStorageClass() != FunctionDecl::Extern) 862 New->setStorageClass(Old->getStorageClass()); 863 864 // Merge "inline" 865 if (Old->isInline()) 866 New->setInline(true); 867 868 // If this function declaration by itself qualifies as a C99 inline 869 // definition (C99 6.7.4p6), but the previous definition did not, 870 // then the function is not a C99 inline definition. 871 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 872 New->setC99InlineDefinition(false); 873 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 874 // Mark all preceding definitions as not being C99 inline definitions. 875 for (const FunctionDecl *Prev = Old; Prev; 876 Prev = Prev->getPreviousDeclaration()) 877 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 878 } 879 880 // Merge "pure" flag. 881 if (Old->isPure()) 882 New->setPure(); 883 884 // Merge the "deleted" flag. 885 if (Old->isDeleted()) 886 New->setDeleted(); 887 888 if (getLangOptions().CPlusPlus) 889 return MergeCXXFunctionDecl(New, Old); 890 891 return false; 892} 893 894/// MergeVarDecl - We just parsed a variable 'New' which has the same name 895/// and scope as a previous declaration 'Old'. Figure out how to resolve this 896/// situation, merging decls or emitting diagnostics as appropriate. 897/// 898/// Tentative definition rules (C99 6.9.2p2) are checked by 899/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 900/// definitions here, since the initializer hasn't been attached. 901/// 902void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 903 // If either decl is invalid, make sure the new one is marked invalid and 904 // don't do any other checking. 905 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 906 return New->setInvalidDecl(); 907 908 // Verify the old decl was also a variable. 909 VarDecl *Old = dyn_cast<VarDecl>(OldD); 910 if (!Old) { 911 Diag(New->getLocation(), diag::err_redefinition_different_kind) 912 << New->getDeclName(); 913 Diag(OldD->getLocation(), diag::note_previous_definition); 914 return New->setInvalidDecl(); 915 } 916 917 MergeAttributes(New, Old, Context); 918 919 // Merge the types 920 QualType MergedT; 921 if (getLangOptions().CPlusPlus) { 922 if (Context.hasSameType(New->getType(), Old->getType())) 923 MergedT = New->getType(); 924 } else { 925 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 926 } 927 if (MergedT.isNull()) { 928 Diag(New->getLocation(), diag::err_redefinition_different_type) 929 << New->getDeclName(); 930 Diag(Old->getLocation(), diag::note_previous_definition); 931 return New->setInvalidDecl(); 932 } 933 New->setType(MergedT); 934 935 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 936 if (New->getStorageClass() == VarDecl::Static && 937 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 938 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 939 Diag(Old->getLocation(), diag::note_previous_definition); 940 return New->setInvalidDecl(); 941 } 942 // C99 6.2.2p4: 943 // For an identifier declared with the storage-class specifier 944 // extern in a scope in which a prior declaration of that 945 // identifier is visible,23) if the prior declaration specifies 946 // internal or external linkage, the linkage of the identifier at 947 // the later declaration is the same as the linkage specified at 948 // the prior declaration. If no prior declaration is visible, or 949 // if the prior declaration specifies no linkage, then the 950 // identifier has external linkage. 951 if (New->hasExternalStorage() && Old->hasLinkage()) 952 /* Okay */; 953 else if (New->getStorageClass() != VarDecl::Static && 954 Old->getStorageClass() == VarDecl::Static) { 955 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 956 Diag(Old->getLocation(), diag::note_previous_definition); 957 return New->setInvalidDecl(); 958 } 959 960 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 961 962 // FIXME: The test for external storage here seems wrong? We still 963 // need to check for mismatches. 964 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 965 // Don't complain about out-of-line definitions of static members. 966 !(Old->getLexicalDeclContext()->isRecord() && 967 !New->getLexicalDeclContext()->isRecord())) { 968 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 969 Diag(Old->getLocation(), diag::note_previous_definition); 970 return New->setInvalidDecl(); 971 } 972 973 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 974 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 975 Diag(Old->getLocation(), diag::note_previous_definition); 976 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 977 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 978 Diag(Old->getLocation(), diag::note_previous_definition); 979 } 980 981 // Keep a chain of previous declarations. 982 New->setPreviousDeclaration(Old); 983} 984 985/// CheckParmsForFunctionDef - Check that the parameters of the given 986/// function are appropriate for the definition of a function. This 987/// takes care of any checks that cannot be performed on the 988/// declaration itself, e.g., that the types of each of the function 989/// parameters are complete. 990bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 991 bool HasInvalidParm = false; 992 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 993 ParmVarDecl *Param = FD->getParamDecl(p); 994 995 // C99 6.7.5.3p4: the parameters in a parameter type list in a 996 // function declarator that is part of a function definition of 997 // that function shall not have incomplete type. 998 // 999 // This is also C++ [dcl.fct]p6. 1000 if (!Param->isInvalidDecl() && 1001 RequireCompleteType(Param->getLocation(), Param->getType(), 1002 diag::err_typecheck_decl_incomplete_type)) { 1003 Param->setInvalidDecl(); 1004 HasInvalidParm = true; 1005 } 1006 1007 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1008 // declaration of each parameter shall include an identifier. 1009 if (Param->getIdentifier() == 0 && 1010 !Param->isImplicit() && 1011 !getLangOptions().CPlusPlus) 1012 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1013 } 1014 1015 return HasInvalidParm; 1016} 1017 1018/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1019/// no declarator (e.g. "struct foo;") is parsed. 1020Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1021 // FIXME: Error on auto/register at file scope 1022 // FIXME: Error on inline/virtual/explicit 1023 // FIXME: Error on invalid restrict 1024 // FIXME: Warn on useless __thread 1025 // FIXME: Warn on useless const/volatile 1026 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1027 // FIXME: Warn on useless attributes 1028 TagDecl *Tag = 0; 1029 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1030 DS.getTypeSpecType() == DeclSpec::TST_struct || 1031 DS.getTypeSpecType() == DeclSpec::TST_union || 1032 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1033 if (!DS.getTypeRep()) // We probably had an error 1034 return DeclPtrTy(); 1035 1036 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1037 } 1038 1039 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1040 if (!Record->getDeclName() && Record->isDefinition() && 1041 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1042 if (getLangOptions().CPlusPlus || 1043 Record->getDeclContext()->isRecord()) 1044 return BuildAnonymousStructOrUnion(S, DS, Record); 1045 1046 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1047 << DS.getSourceRange(); 1048 } 1049 1050 // Microsoft allows unnamed struct/union fields. Don't complain 1051 // about them. 1052 // FIXME: Should we support Microsoft's extensions in this area? 1053 if (Record->getDeclName() && getLangOptions().Microsoft) 1054 return DeclPtrTy::make(Tag); 1055 } 1056 1057 if (!DS.isMissingDeclaratorOk() && 1058 DS.getTypeSpecType() != DeclSpec::TST_error) { 1059 // Warn about typedefs of enums without names, since this is an 1060 // extension in both Microsoft an GNU. 1061 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1062 Tag && isa<EnumDecl>(Tag)) { 1063 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1064 << DS.getSourceRange(); 1065 return DeclPtrTy::make(Tag); 1066 } 1067 1068 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1069 << DS.getSourceRange(); 1070 return DeclPtrTy(); 1071 } 1072 1073 return DeclPtrTy::make(Tag); 1074} 1075 1076/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1077/// anonymous struct or union AnonRecord into the owning context Owner 1078/// and scope S. This routine will be invoked just after we realize 1079/// that an unnamed union or struct is actually an anonymous union or 1080/// struct, e.g., 1081/// 1082/// @code 1083/// union { 1084/// int i; 1085/// float f; 1086/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1087/// // f into the surrounding scope.x 1088/// @endcode 1089/// 1090/// This routine is recursive, injecting the names of nested anonymous 1091/// structs/unions into the owning context and scope as well. 1092bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1093 RecordDecl *AnonRecord) { 1094 bool Invalid = false; 1095 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1096 FEnd = AnonRecord->field_end(Context); 1097 F != FEnd; ++F) { 1098 if ((*F)->getDeclName()) { 1099 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1100 LookupOrdinaryName, true); 1101 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1102 // C++ [class.union]p2: 1103 // The names of the members of an anonymous union shall be 1104 // distinct from the names of any other entity in the 1105 // scope in which the anonymous union is declared. 1106 unsigned diagKind 1107 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1108 : diag::err_anonymous_struct_member_redecl; 1109 Diag((*F)->getLocation(), diagKind) 1110 << (*F)->getDeclName(); 1111 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1112 Invalid = true; 1113 } else { 1114 // C++ [class.union]p2: 1115 // For the purpose of name lookup, after the anonymous union 1116 // definition, the members of the anonymous union are 1117 // considered to have been defined in the scope in which the 1118 // anonymous union is declared. 1119 Owner->makeDeclVisibleInContext(Context, *F); 1120 S->AddDecl(DeclPtrTy::make(*F)); 1121 IdResolver.AddDecl(*F); 1122 } 1123 } else if (const RecordType *InnerRecordType 1124 = (*F)->getType()->getAsRecordType()) { 1125 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1126 if (InnerRecord->isAnonymousStructOrUnion()) 1127 Invalid = Invalid || 1128 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1129 } 1130 } 1131 1132 return Invalid; 1133} 1134 1135/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1136/// anonymous structure or union. Anonymous unions are a C++ feature 1137/// (C++ [class.union]) and a GNU C extension; anonymous structures 1138/// are a GNU C and GNU C++ extension. 1139Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1140 RecordDecl *Record) { 1141 DeclContext *Owner = Record->getDeclContext(); 1142 1143 // Diagnose whether this anonymous struct/union is an extension. 1144 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1145 Diag(Record->getLocation(), diag::ext_anonymous_union); 1146 else if (!Record->isUnion()) 1147 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1148 1149 // C and C++ require different kinds of checks for anonymous 1150 // structs/unions. 1151 bool Invalid = false; 1152 if (getLangOptions().CPlusPlus) { 1153 const char* PrevSpec = 0; 1154 // C++ [class.union]p3: 1155 // Anonymous unions declared in a named namespace or in the 1156 // global namespace shall be declared static. 1157 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1158 (isa<TranslationUnitDecl>(Owner) || 1159 (isa<NamespaceDecl>(Owner) && 1160 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1161 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1162 Invalid = true; 1163 1164 // Recover by adding 'static'. 1165 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1166 } 1167 // C++ [class.union]p3: 1168 // A storage class is not allowed in a declaration of an 1169 // anonymous union in a class scope. 1170 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1171 isa<RecordDecl>(Owner)) { 1172 Diag(DS.getStorageClassSpecLoc(), 1173 diag::err_anonymous_union_with_storage_spec); 1174 Invalid = true; 1175 1176 // Recover by removing the storage specifier. 1177 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1178 PrevSpec); 1179 } 1180 1181 // C++ [class.union]p2: 1182 // The member-specification of an anonymous union shall only 1183 // define non-static data members. [Note: nested types and 1184 // functions cannot be declared within an anonymous union. ] 1185 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1186 MemEnd = Record->decls_end(Context); 1187 Mem != MemEnd; ++Mem) { 1188 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1189 // C++ [class.union]p3: 1190 // An anonymous union shall not have private or protected 1191 // members (clause 11). 1192 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1193 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1194 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1195 Invalid = true; 1196 } 1197 } else if ((*Mem)->isImplicit()) { 1198 // Any implicit members are fine. 1199 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1200 // This is a type that showed up in an 1201 // elaborated-type-specifier inside the anonymous struct or 1202 // union, but which actually declares a type outside of the 1203 // anonymous struct or union. It's okay. 1204 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1205 if (!MemRecord->isAnonymousStructOrUnion() && 1206 MemRecord->getDeclName()) { 1207 // This is a nested type declaration. 1208 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1209 << (int)Record->isUnion(); 1210 Invalid = true; 1211 } 1212 } else { 1213 // We have something that isn't a non-static data 1214 // member. Complain about it. 1215 unsigned DK = diag::err_anonymous_record_bad_member; 1216 if (isa<TypeDecl>(*Mem)) 1217 DK = diag::err_anonymous_record_with_type; 1218 else if (isa<FunctionDecl>(*Mem)) 1219 DK = diag::err_anonymous_record_with_function; 1220 else if (isa<VarDecl>(*Mem)) 1221 DK = diag::err_anonymous_record_with_static; 1222 Diag((*Mem)->getLocation(), DK) 1223 << (int)Record->isUnion(); 1224 Invalid = true; 1225 } 1226 } 1227 } 1228 1229 if (!Record->isUnion() && !Owner->isRecord()) { 1230 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1231 << (int)getLangOptions().CPlusPlus; 1232 Invalid = true; 1233 } 1234 1235 // Create a declaration for this anonymous struct/union. 1236 NamedDecl *Anon = 0; 1237 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1238 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1239 /*IdentifierInfo=*/0, 1240 Context.getTypeDeclType(Record), 1241 /*BitWidth=*/0, /*Mutable=*/false); 1242 Anon->setAccess(AS_public); 1243 if (getLangOptions().CPlusPlus) 1244 FieldCollector->Add(cast<FieldDecl>(Anon)); 1245 } else { 1246 VarDecl::StorageClass SC; 1247 switch (DS.getStorageClassSpec()) { 1248 default: assert(0 && "Unknown storage class!"); 1249 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1250 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1251 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1252 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1253 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1254 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1255 case DeclSpec::SCS_mutable: 1256 // mutable can only appear on non-static class members, so it's always 1257 // an error here 1258 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1259 Invalid = true; 1260 SC = VarDecl::None; 1261 break; 1262 } 1263 1264 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1265 /*IdentifierInfo=*/0, 1266 Context.getTypeDeclType(Record), 1267 SC, DS.getSourceRange().getBegin()); 1268 } 1269 Anon->setImplicit(); 1270 1271 // Add the anonymous struct/union object to the current 1272 // context. We'll be referencing this object when we refer to one of 1273 // its members. 1274 Owner->addDecl(Context, Anon); 1275 1276 // Inject the members of the anonymous struct/union into the owning 1277 // context and into the identifier resolver chain for name lookup 1278 // purposes. 1279 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1280 Invalid = true; 1281 1282 // Mark this as an anonymous struct/union type. Note that we do not 1283 // do this until after we have already checked and injected the 1284 // members of this anonymous struct/union type, because otherwise 1285 // the members could be injected twice: once by DeclContext when it 1286 // builds its lookup table, and once by 1287 // InjectAnonymousStructOrUnionMembers. 1288 Record->setAnonymousStructOrUnion(true); 1289 1290 if (Invalid) 1291 Anon->setInvalidDecl(); 1292 1293 return DeclPtrTy::make(Anon); 1294} 1295 1296 1297/// GetNameForDeclarator - Determine the full declaration name for the 1298/// given Declarator. 1299DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1300 switch (D.getKind()) { 1301 case Declarator::DK_Abstract: 1302 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1303 return DeclarationName(); 1304 1305 case Declarator::DK_Normal: 1306 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1307 return DeclarationName(D.getIdentifier()); 1308 1309 case Declarator::DK_Constructor: { 1310 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1311 Ty = Context.getCanonicalType(Ty); 1312 return Context.DeclarationNames.getCXXConstructorName(Ty); 1313 } 1314 1315 case Declarator::DK_Destructor: { 1316 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1317 Ty = Context.getCanonicalType(Ty); 1318 return Context.DeclarationNames.getCXXDestructorName(Ty); 1319 } 1320 1321 case Declarator::DK_Conversion: { 1322 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1323 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1324 Ty = Context.getCanonicalType(Ty); 1325 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1326 } 1327 1328 case Declarator::DK_Operator: 1329 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1330 return Context.DeclarationNames.getCXXOperatorName( 1331 D.getOverloadedOperator()); 1332 } 1333 1334 assert(false && "Unknown name kind"); 1335 return DeclarationName(); 1336} 1337 1338/// isNearlyMatchingFunction - Determine whether the C++ functions 1339/// Declaration and Definition are "nearly" matching. This heuristic 1340/// is used to improve diagnostics in the case where an out-of-line 1341/// function definition doesn't match any declaration within 1342/// the class or namespace. 1343static bool isNearlyMatchingFunction(ASTContext &Context, 1344 FunctionDecl *Declaration, 1345 FunctionDecl *Definition) { 1346 if (Declaration->param_size() != Definition->param_size()) 1347 return false; 1348 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1349 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1350 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1351 1352 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1353 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1354 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1355 return false; 1356 } 1357 1358 return true; 1359} 1360 1361Sema::DeclPtrTy 1362Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1363 DeclarationName Name = GetNameForDeclarator(D); 1364 1365 // All of these full declarators require an identifier. If it doesn't have 1366 // one, the ParsedFreeStandingDeclSpec action should be used. 1367 if (!Name) { 1368 if (!D.isInvalidType()) // Reject this if we think it is valid. 1369 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1370 diag::err_declarator_need_ident) 1371 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1372 return DeclPtrTy(); 1373 } 1374 1375 // The scope passed in may not be a decl scope. Zip up the scope tree until 1376 // we find one that is. 1377 while ((S->getFlags() & Scope::DeclScope) == 0 || 1378 (S->getFlags() & Scope::TemplateParamScope) != 0) 1379 S = S->getParent(); 1380 1381 DeclContext *DC; 1382 NamedDecl *PrevDecl; 1383 NamedDecl *New; 1384 1385 QualType R = GetTypeForDeclarator(D, S); 1386 1387 // See if this is a redefinition of a variable in the same scope. 1388 if (D.getCXXScopeSpec().isInvalid()) { 1389 DC = CurContext; 1390 PrevDecl = 0; 1391 D.setInvalidType(); 1392 } else if (!D.getCXXScopeSpec().isSet()) { 1393 LookupNameKind NameKind = LookupOrdinaryName; 1394 1395 // If the declaration we're planning to build will be a function 1396 // or object with linkage, then look for another declaration with 1397 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1398 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1399 /* Do nothing*/; 1400 else if (R->isFunctionType()) { 1401 if (CurContext->isFunctionOrMethod()) 1402 NameKind = LookupRedeclarationWithLinkage; 1403 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1404 NameKind = LookupRedeclarationWithLinkage; 1405 1406 DC = CurContext; 1407 PrevDecl = LookupName(S, Name, NameKind, true, 1408 D.getDeclSpec().getStorageClassSpec() != 1409 DeclSpec::SCS_static, 1410 D.getIdentifierLoc()); 1411 } else { // Something like "int foo::x;" 1412 DC = computeDeclContext(D.getCXXScopeSpec()); 1413 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1414 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1415 1416 // C++ 7.3.1.2p2: 1417 // Members (including explicit specializations of templates) of a named 1418 // namespace can also be defined outside that namespace by explicit 1419 // qualification of the name being defined, provided that the entity being 1420 // defined was already declared in the namespace and the definition appears 1421 // after the point of declaration in a namespace that encloses the 1422 // declarations namespace. 1423 // 1424 // Note that we only check the context at this point. We don't yet 1425 // have enough information to make sure that PrevDecl is actually 1426 // the declaration we want to match. For example, given: 1427 // 1428 // class X { 1429 // void f(); 1430 // void f(float); 1431 // }; 1432 // 1433 // void X::f(int) { } // ill-formed 1434 // 1435 // In this case, PrevDecl will point to the overload set 1436 // containing the two f's declared in X, but neither of them 1437 // matches. 1438 1439 // First check whether we named the global scope. 1440 if (isa<TranslationUnitDecl>(DC)) { 1441 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1442 << Name << D.getCXXScopeSpec().getRange(); 1443 } else if (!CurContext->Encloses(DC)) { 1444 // The qualifying scope doesn't enclose the original declaration. 1445 // Emit diagnostic based on current scope. 1446 SourceLocation L = D.getIdentifierLoc(); 1447 SourceRange R = D.getCXXScopeSpec().getRange(); 1448 if (isa<FunctionDecl>(CurContext)) 1449 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1450 else 1451 Diag(L, diag::err_invalid_declarator_scope) 1452 << Name << cast<NamedDecl>(DC) << R; 1453 D.setInvalidType(); 1454 } 1455 } 1456 1457 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1458 // Maybe we will complain about the shadowed template parameter. 1459 if (!D.isInvalidType()) 1460 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1461 D.setInvalidType(); 1462 1463 // Just pretend that we didn't see the previous declaration. 1464 PrevDecl = 0; 1465 } 1466 1467 // In C++, the previous declaration we find might be a tag type 1468 // (class or enum). In this case, the new declaration will hide the 1469 // tag type. Note that this does does not apply if we're declaring a 1470 // typedef (C++ [dcl.typedef]p4). 1471 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1472 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1473 PrevDecl = 0; 1474 1475 bool Redeclaration = false; 1476 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1477 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1478 } else if (R->isFunctionType()) { 1479 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1480 IsFunctionDefinition, Redeclaration); 1481 } else { 1482 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1483 } 1484 1485 if (New == 0) 1486 return DeclPtrTy(); 1487 1488 // If this has an identifier and is not an invalid redeclaration, 1489 // add it to the scope stack. 1490 if (Name && !(Redeclaration && New->isInvalidDecl())) 1491 PushOnScopeChains(New, S); 1492 1493 return DeclPtrTy::make(New); 1494} 1495 1496/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1497/// types into constant array types in certain situations which would otherwise 1498/// be errors (for GCC compatibility). 1499static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1500 ASTContext &Context, 1501 bool &SizeIsNegative) { 1502 // This method tries to turn a variable array into a constant 1503 // array even when the size isn't an ICE. This is necessary 1504 // for compatibility with code that depends on gcc's buggy 1505 // constant expression folding, like struct {char x[(int)(char*)2];} 1506 SizeIsNegative = false; 1507 1508 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1509 QualType Pointee = PTy->getPointeeType(); 1510 QualType FixedType = 1511 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1512 if (FixedType.isNull()) return FixedType; 1513 FixedType = Context.getPointerType(FixedType); 1514 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1515 return FixedType; 1516 } 1517 1518 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1519 if (!VLATy) 1520 return QualType(); 1521 // FIXME: We should probably handle this case 1522 if (VLATy->getElementType()->isVariablyModifiedType()) 1523 return QualType(); 1524 1525 Expr::EvalResult EvalResult; 1526 if (!VLATy->getSizeExpr() || 1527 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1528 !EvalResult.Val.isInt()) 1529 return QualType(); 1530 1531 llvm::APSInt &Res = EvalResult.Val.getInt(); 1532 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1533 return Context.getConstantArrayType(VLATy->getElementType(), 1534 Res, ArrayType::Normal, 0); 1535 1536 SizeIsNegative = true; 1537 return QualType(); 1538} 1539 1540/// \brief Register the given locally-scoped external C declaration so 1541/// that it can be found later for redeclarations 1542void 1543Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1544 Scope *S) { 1545 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1546 "Decl is not a locally-scoped decl!"); 1547 // Note that we have a locally-scoped external with this name. 1548 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1549 1550 if (!PrevDecl) 1551 return; 1552 1553 // If there was a previous declaration of this variable, it may be 1554 // in our identifier chain. Update the identifier chain with the new 1555 // declaration. 1556 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1557 // The previous declaration was found on the identifer resolver 1558 // chain, so remove it from its scope. 1559 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1560 S = S->getParent(); 1561 1562 if (S) 1563 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1564 } 1565} 1566 1567/// \brief Diagnose function specifiers on a declaration of an identifier that 1568/// does not identify a function. 1569void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1570 // FIXME: We should probably indicate the identifier in question to avoid 1571 // confusion for constructs like "inline int a(), b;" 1572 if (D.getDeclSpec().isInlineSpecified()) 1573 Diag(D.getDeclSpec().getInlineSpecLoc(), 1574 diag::err_inline_non_function); 1575 1576 if (D.getDeclSpec().isVirtualSpecified()) 1577 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1578 diag::err_virtual_non_function); 1579 1580 if (D.getDeclSpec().isExplicitSpecified()) 1581 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1582 diag::err_explicit_non_function); 1583} 1584 1585NamedDecl* 1586Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1587 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1588 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1589 if (D.getCXXScopeSpec().isSet()) { 1590 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1591 << D.getCXXScopeSpec().getRange(); 1592 D.setInvalidType(); 1593 // Pretend we didn't see the scope specifier. 1594 DC = 0; 1595 } 1596 1597 if (getLangOptions().CPlusPlus) { 1598 // Check that there are no default arguments (C++ only). 1599 CheckExtraCXXDefaultArguments(D); 1600 } 1601 1602 DiagnoseFunctionSpecifiers(D); 1603 1604 if (D.getDeclSpec().isThreadSpecified()) 1605 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1606 1607 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1608 if (!NewTD) return 0; 1609 1610 if (D.isInvalidType()) 1611 NewTD->setInvalidDecl(); 1612 1613 // Handle attributes prior to checking for duplicates in MergeVarDecl 1614 ProcessDeclAttributes(NewTD, D); 1615 // Merge the decl with the existing one if appropriate. If the decl is 1616 // in an outer scope, it isn't the same thing. 1617 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1618 Redeclaration = true; 1619 MergeTypeDefDecl(NewTD, PrevDecl); 1620 } 1621 1622 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1623 // then it shall have block scope. 1624 QualType T = NewTD->getUnderlyingType(); 1625 if (T->isVariablyModifiedType()) { 1626 CurFunctionNeedsScopeChecking = true; 1627 1628 if (S->getFnParent() == 0) { 1629 bool SizeIsNegative; 1630 QualType FixedTy = 1631 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1632 if (!FixedTy.isNull()) { 1633 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1634 NewTD->setUnderlyingType(FixedTy); 1635 } else { 1636 if (SizeIsNegative) 1637 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1638 else if (T->isVariableArrayType()) 1639 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1640 else 1641 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1642 NewTD->setInvalidDecl(); 1643 } 1644 } 1645 } 1646 return NewTD; 1647} 1648 1649/// \brief Determines whether the given declaration is an out-of-scope 1650/// previous declaration. 1651/// 1652/// This routine should be invoked when name lookup has found a 1653/// previous declaration (PrevDecl) that is not in the scope where a 1654/// new declaration by the same name is being introduced. If the new 1655/// declaration occurs in a local scope, previous declarations with 1656/// linkage may still be considered previous declarations (C99 1657/// 6.2.2p4-5, C++ [basic.link]p6). 1658/// 1659/// \param PrevDecl the previous declaration found by name 1660/// lookup 1661/// 1662/// \param DC the context in which the new declaration is being 1663/// declared. 1664/// 1665/// \returns true if PrevDecl is an out-of-scope previous declaration 1666/// for a new delcaration with the same name. 1667static bool 1668isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1669 ASTContext &Context) { 1670 if (!PrevDecl) 1671 return 0; 1672 1673 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1674 // case we need to check each of the overloaded functions. 1675 if (!PrevDecl->hasLinkage()) 1676 return false; 1677 1678 if (Context.getLangOptions().CPlusPlus) { 1679 // C++ [basic.link]p6: 1680 // If there is a visible declaration of an entity with linkage 1681 // having the same name and type, ignoring entities declared 1682 // outside the innermost enclosing namespace scope, the block 1683 // scope declaration declares that same entity and receives the 1684 // linkage of the previous declaration. 1685 DeclContext *OuterContext = DC->getLookupContext(); 1686 if (!OuterContext->isFunctionOrMethod()) 1687 // This rule only applies to block-scope declarations. 1688 return false; 1689 else { 1690 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1691 if (PrevOuterContext->isRecord()) 1692 // We found a member function: ignore it. 1693 return false; 1694 else { 1695 // Find the innermost enclosing namespace for the new and 1696 // previous declarations. 1697 while (!OuterContext->isFileContext()) 1698 OuterContext = OuterContext->getParent(); 1699 while (!PrevOuterContext->isFileContext()) 1700 PrevOuterContext = PrevOuterContext->getParent(); 1701 1702 // The previous declaration is in a different namespace, so it 1703 // isn't the same function. 1704 if (OuterContext->getPrimaryContext() != 1705 PrevOuterContext->getPrimaryContext()) 1706 return false; 1707 } 1708 } 1709 } 1710 1711 return true; 1712} 1713 1714NamedDecl* 1715Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1716 QualType R,NamedDecl* PrevDecl, 1717 bool &Redeclaration) { 1718 DeclarationName Name = GetNameForDeclarator(D); 1719 1720 // Check that there are no default arguments (C++ only). 1721 if (getLangOptions().CPlusPlus) 1722 CheckExtraCXXDefaultArguments(D); 1723 1724 VarDecl *NewVD; 1725 VarDecl::StorageClass SC; 1726 switch (D.getDeclSpec().getStorageClassSpec()) { 1727 default: assert(0 && "Unknown storage class!"); 1728 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1729 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1730 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1731 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1732 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1733 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1734 case DeclSpec::SCS_mutable: 1735 // mutable can only appear on non-static class members, so it's always 1736 // an error here 1737 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1738 D.setInvalidType(); 1739 SC = VarDecl::None; 1740 break; 1741 } 1742 1743 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1744 if (!II) { 1745 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1746 << Name.getAsString(); 1747 return 0; 1748 } 1749 1750 DiagnoseFunctionSpecifiers(D); 1751 1752 if (!DC->isRecord() && S->getFnParent() == 0) { 1753 // C99 6.9p2: The storage-class specifiers auto and register shall not 1754 // appear in the declaration specifiers in an external declaration. 1755 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1756 1757 // If this is a register variable with an asm label specified, then this 1758 // is a GNU extension. 1759 if (SC == VarDecl::Register && D.getAsmLabel()) 1760 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1761 else 1762 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1763 D.setInvalidType(); 1764 } 1765 } 1766 if (DC->isRecord() && !CurContext->isRecord()) { 1767 // This is an out-of-line definition of a static data member. 1768 if (SC == VarDecl::Static) { 1769 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1770 diag::err_static_out_of_line) 1771 << CodeModificationHint::CreateRemoval( 1772 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1773 } else if (SC == VarDecl::None) 1774 SC = VarDecl::Static; 1775 } 1776 1777 // The variable can not 1778 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1779 II, R, SC, 1780 // FIXME: Move to DeclGroup... 1781 D.getDeclSpec().getSourceRange().getBegin()); 1782 1783 if (D.isInvalidType()) 1784 NewVD->setInvalidDecl(); 1785 1786 if (D.getDeclSpec().isThreadSpecified()) { 1787 if (NewVD->hasLocalStorage()) 1788 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1789 else if (!Context.Target.isTLSSupported()) 1790 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1791 else 1792 NewVD->setThreadSpecified(true); 1793 } 1794 1795 // Set the lexical context. If the declarator has a C++ scope specifier, the 1796 // lexical context will be different from the semantic context. 1797 NewVD->setLexicalDeclContext(CurContext); 1798 1799 // Handle attributes prior to checking for duplicates in MergeVarDecl 1800 ProcessDeclAttributes(NewVD, D); 1801 1802 // Handle GNU asm-label extension (encoded as an attribute). 1803 if (Expr *E = (Expr*) D.getAsmLabel()) { 1804 // The parser guarantees this is a string. 1805 StringLiteral *SE = cast<StringLiteral>(E); 1806 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1807 SE->getByteLength()))); 1808 } 1809 1810 // If name lookup finds a previous declaration that is not in the 1811 // same scope as the new declaration, this may still be an 1812 // acceptable redeclaration. 1813 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1814 !(NewVD->hasLinkage() && 1815 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1816 PrevDecl = 0; 1817 1818 // Merge the decl with the existing one if appropriate. 1819 if (PrevDecl) { 1820 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1821 // The user tried to define a non-static data member 1822 // out-of-line (C++ [dcl.meaning]p1). 1823 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1824 << D.getCXXScopeSpec().getRange(); 1825 PrevDecl = 0; 1826 NewVD->setInvalidDecl(); 1827 } 1828 } else if (D.getCXXScopeSpec().isSet()) { 1829 // No previous declaration in the qualifying scope. 1830 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1831 << Name << D.getCXXScopeSpec().getRange(); 1832 NewVD->setInvalidDecl(); 1833 } 1834 1835 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1836 1837 // If this is a locally-scoped extern C variable, update the map of 1838 // such variables. 1839 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1840 !NewVD->isInvalidDecl()) 1841 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1842 1843 return NewVD; 1844} 1845 1846/// \brief Perform semantic checking on a newly-created variable 1847/// declaration. 1848/// 1849/// This routine performs all of the type-checking required for a 1850/// variable declaration once it has been built. It is used both to 1851/// check variables after they have been parsed and their declarators 1852/// have been translated into a declaration, and to check variables 1853/// that have been instantiated from a template. 1854/// 1855/// Sets NewVD->isInvalidDecl() if an error was encountered. 1856void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1857 bool &Redeclaration) { 1858 // If the decl is already known invalid, don't check it. 1859 if (NewVD->isInvalidDecl()) 1860 return; 1861 1862 QualType T = NewVD->getType(); 1863 1864 if (T->isObjCInterfaceType()) { 1865 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1866 return NewVD->setInvalidDecl(); 1867 } 1868 1869 // The variable can not have an abstract class type. 1870 if (RequireNonAbstractType(NewVD->getLocation(), T, 1871 diag::err_abstract_type_in_decl, 1872 AbstractVariableType)) 1873 return NewVD->setInvalidDecl(); 1874 1875 // Emit an error if an address space was applied to decl with local storage. 1876 // This includes arrays of objects with address space qualifiers, but not 1877 // automatic variables that point to other address spaces. 1878 // ISO/IEC TR 18037 S5.1.2 1879 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1880 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1881 return NewVD->setInvalidDecl(); 1882 } 1883 1884 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1885 && !NewVD->hasAttr<BlocksAttr>()) 1886 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1887 1888 bool isVM = T->isVariablyModifiedType(); 1889 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1890 CurFunctionNeedsScopeChecking = true; 1891 1892 if ((isVM && NewVD->hasLinkage()) || 1893 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1894 bool SizeIsNegative; 1895 QualType FixedTy = 1896 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1897 1898 if (FixedTy.isNull() && T->isVariableArrayType()) { 1899 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1900 // FIXME: This won't give the correct result for 1901 // int a[10][n]; 1902 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1903 1904 if (NewVD->isFileVarDecl()) 1905 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1906 << SizeRange; 1907 else if (NewVD->getStorageClass() == VarDecl::Static) 1908 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1909 << SizeRange; 1910 else 1911 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1912 << SizeRange; 1913 return NewVD->setInvalidDecl(); 1914 } 1915 1916 if (FixedTy.isNull()) { 1917 if (NewVD->isFileVarDecl()) 1918 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1919 else 1920 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1921 return NewVD->setInvalidDecl(); 1922 } 1923 1924 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1925 NewVD->setType(FixedTy); 1926 } 1927 1928 if (!PrevDecl && NewVD->isExternC(Context)) { 1929 // Since we did not find anything by this name and we're declaring 1930 // an extern "C" variable, look for a non-visible extern "C" 1931 // declaration with the same name. 1932 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1933 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1934 if (Pos != LocallyScopedExternalDecls.end()) 1935 PrevDecl = Pos->second; 1936 } 1937 1938 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1939 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1940 << T; 1941 return NewVD->setInvalidDecl(); 1942 } 1943 1944 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 1945 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 1946 return NewVD->setInvalidDecl(); 1947 } 1948 1949 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 1950 Diag(NewVD->getLocation(), diag::err_block_on_vm); 1951 return NewVD->setInvalidDecl(); 1952 } 1953 1954 if (PrevDecl) { 1955 Redeclaration = true; 1956 MergeVarDecl(NewVD, PrevDecl); 1957 } 1958} 1959 1960NamedDecl* 1961Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1962 QualType R, NamedDecl* PrevDecl, 1963 bool IsFunctionDefinition, bool &Redeclaration) { 1964 assert(R.getTypePtr()->isFunctionType()); 1965 1966 DeclarationName Name = GetNameForDeclarator(D); 1967 FunctionDecl::StorageClass SC = FunctionDecl::None; 1968 switch (D.getDeclSpec().getStorageClassSpec()) { 1969 default: assert(0 && "Unknown storage class!"); 1970 case DeclSpec::SCS_auto: 1971 case DeclSpec::SCS_register: 1972 case DeclSpec::SCS_mutable: 1973 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1974 diag::err_typecheck_sclass_func); 1975 D.setInvalidType(); 1976 break; 1977 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1978 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1979 case DeclSpec::SCS_static: { 1980 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1981 // C99 6.7.1p5: 1982 // The declaration of an identifier for a function that has 1983 // block scope shall have no explicit storage-class specifier 1984 // other than extern 1985 // See also (C++ [dcl.stc]p4). 1986 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1987 diag::err_static_block_func); 1988 SC = FunctionDecl::None; 1989 } else 1990 SC = FunctionDecl::Static; 1991 break; 1992 } 1993 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1994 } 1995 1996 if (D.getDeclSpec().isThreadSpecified()) 1997 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1998 1999 bool isInline = D.getDeclSpec().isInlineSpecified(); 2000 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2001 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2002 2003 // Check that the return type is not an abstract class type. 2004 // For record types, this is done by the AbstractClassUsageDiagnoser once 2005 // the class has been completely parsed. 2006 if (!DC->isRecord() && 2007 RequireNonAbstractType(D.getIdentifierLoc(), 2008 R->getAsFunctionType()->getResultType(), 2009 diag::err_abstract_type_in_decl, 2010 AbstractReturnType)) 2011 D.setInvalidType(); 2012 2013 // Do not allow returning a objc interface by-value. 2014 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2015 Diag(D.getIdentifierLoc(), 2016 diag::err_object_cannot_be_passed_returned_by_value) << 0 2017 << R->getAsFunctionType()->getResultType(); 2018 D.setInvalidType(); 2019 } 2020 2021 bool isVirtualOkay = false; 2022 FunctionDecl *NewFD; 2023 if (D.getKind() == Declarator::DK_Constructor) { 2024 // This is a C++ constructor declaration. 2025 assert(DC->isRecord() && 2026 "Constructors can only be declared in a member context"); 2027 2028 R = CheckConstructorDeclarator(D, R, SC); 2029 2030 // Create the new declaration 2031 NewFD = CXXConstructorDecl::Create(Context, 2032 cast<CXXRecordDecl>(DC), 2033 D.getIdentifierLoc(), Name, R, 2034 isExplicit, isInline, 2035 /*isImplicitlyDeclared=*/false); 2036 } else if (D.getKind() == Declarator::DK_Destructor) { 2037 // This is a C++ destructor declaration. 2038 if (DC->isRecord()) { 2039 R = CheckDestructorDeclarator(D, SC); 2040 2041 NewFD = CXXDestructorDecl::Create(Context, 2042 cast<CXXRecordDecl>(DC), 2043 D.getIdentifierLoc(), Name, R, 2044 isInline, 2045 /*isImplicitlyDeclared=*/false); 2046 2047 isVirtualOkay = true; 2048 } else { 2049 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2050 2051 // Create a FunctionDecl to satisfy the function definition parsing 2052 // code path. 2053 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2054 Name, R, SC, isInline, 2055 /*hasPrototype=*/true, 2056 // FIXME: Move to DeclGroup... 2057 D.getDeclSpec().getSourceRange().getBegin()); 2058 D.setInvalidType(); 2059 } 2060 } else if (D.getKind() == Declarator::DK_Conversion) { 2061 if (!DC->isRecord()) { 2062 Diag(D.getIdentifierLoc(), 2063 diag::err_conv_function_not_member); 2064 return 0; 2065 } 2066 2067 CheckConversionDeclarator(D, R, SC); 2068 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2069 D.getIdentifierLoc(), Name, R, 2070 isInline, isExplicit); 2071 2072 isVirtualOkay = true; 2073 } else if (DC->isRecord()) { 2074 // If the of the function is the same as the name of the record, then this 2075 // must be an invalid constructor that has a return type. 2076 // (The parser checks for a return type and makes the declarator a 2077 // constructor if it has no return type). 2078 // must have an invalid constructor that has a return type 2079 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2080 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2081 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2082 << SourceRange(D.getIdentifierLoc()); 2083 return 0; 2084 } 2085 2086 // This is a C++ method declaration. 2087 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2088 D.getIdentifierLoc(), Name, R, 2089 (SC == FunctionDecl::Static), isInline); 2090 2091 isVirtualOkay = (SC != FunctionDecl::Static); 2092 } else { 2093 // Determine whether the function was written with a 2094 // prototype. This true when: 2095 // - we're in C++ (where every function has a prototype), 2096 // - there is a prototype in the declarator, or 2097 // - the type R of the function is some kind of typedef or other reference 2098 // to a type name (which eventually refers to a function type). 2099 bool HasPrototype = 2100 getLangOptions().CPlusPlus || 2101 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2102 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2103 2104 NewFD = FunctionDecl::Create(Context, DC, 2105 D.getIdentifierLoc(), 2106 Name, R, SC, isInline, HasPrototype, 2107 // FIXME: Move to DeclGroup... 2108 D.getDeclSpec().getSourceRange().getBegin()); 2109 } 2110 2111 if (D.isInvalidType()) 2112 NewFD->setInvalidDecl(); 2113 2114 // Set the lexical context. If the declarator has a C++ 2115 // scope specifier, the lexical context will be different 2116 // from the semantic context. 2117 NewFD->setLexicalDeclContext(CurContext); 2118 2119 // C++ [dcl.fct.spec]p5: 2120 // The virtual specifier shall only be used in declarations of 2121 // nonstatic class member functions that appear within a 2122 // member-specification of a class declaration; see 10.3. 2123 // 2124 if (isVirtual && !NewFD->isInvalidDecl()) { 2125 if (!isVirtualOkay) { 2126 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2127 diag::err_virtual_non_function); 2128 } else if (!CurContext->isRecord()) { 2129 // 'virtual' was specified outside of the class. 2130 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2131 << CodeModificationHint::CreateRemoval( 2132 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2133 } else { 2134 // Okay: Add virtual to the method. 2135 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2136 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2137 CurClass->setAggregate(false); 2138 CurClass->setPOD(false); 2139 CurClass->setPolymorphic(true); 2140 CurClass->setHasTrivialConstructor(false); 2141 } 2142 } 2143 2144 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2145 // Look for virtual methods in base classes that this method might override. 2146 2147 BasePaths Paths; 2148 // FIXME: This will not include hidden member functions. 2149 if (LookupInBases(cast<CXXRecordDecl>(DC), 2150 MemberLookupCriteria(Name, LookupMemberName, 2151 // FIXME: Shouldn't IDNS_Member be 2152 // enough here? 2153 Decl::IDNS_Member | 2154 Decl::IDNS_Ordinary), Paths)) { 2155 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2156 E = Paths.found_decls_end(); I != E; ++I) { 2157 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2158 OverloadedFunctionDecl::function_iterator MatchedDecl; 2159 // FIXME: Is this OK? Should it be done by LookupInBases? 2160 if (IsOverload(NewMD, OldMD, MatchedDecl)) 2161 continue; 2162 if (!OldMD->isVirtual()) 2163 continue; 2164 2165 if (!CheckOverridingFunctionReturnType(NewMD, OldMD)) 2166 NewMD->addOverriddenMethod(OldMD); 2167 } 2168 } 2169 } 2170 } 2171 2172 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2173 !CurContext->isRecord()) { 2174 // C++ [class.static]p1: 2175 // A data or function member of a class may be declared static 2176 // in a class definition, in which case it is a static member of 2177 // the class. 2178 2179 // Complain about the 'static' specifier if it's on an out-of-line 2180 // member function definition. 2181 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2182 diag::err_static_out_of_line) 2183 << CodeModificationHint::CreateRemoval( 2184 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2185 } 2186 2187 // Handle GNU asm-label extension (encoded as an attribute). 2188 if (Expr *E = (Expr*) D.getAsmLabel()) { 2189 // The parser guarantees this is a string. 2190 StringLiteral *SE = cast<StringLiteral>(E); 2191 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2192 SE->getByteLength()))); 2193 } 2194 2195 // Copy the parameter declarations from the declarator D to the function 2196 // declaration NewFD, if they are available. First scavenge them into Params. 2197 llvm::SmallVector<ParmVarDecl*, 16> Params; 2198 if (D.getNumTypeObjects() > 0) { 2199 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2200 2201 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2202 // function that takes no arguments, not a function that takes a 2203 // single void argument. 2204 // We let through "const void" here because Sema::GetTypeForDeclarator 2205 // already checks for that case. 2206 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2207 FTI.ArgInfo[0].Param && 2208 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2209 // Empty arg list, don't push any params. 2210 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2211 2212 // In C++, the empty parameter-type-list must be spelled "void"; a 2213 // typedef of void is not permitted. 2214 if (getLangOptions().CPlusPlus && 2215 Param->getType().getUnqualifiedType() != Context.VoidTy) 2216 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2217 // FIXME: Leaks decl? 2218 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2219 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2220 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2221 } 2222 2223 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2224 // When we're declaring a function with a typedef, typeof, etc as in the 2225 // following example, we'll need to synthesize (unnamed) 2226 // parameters for use in the declaration. 2227 // 2228 // @code 2229 // typedef void fn(int); 2230 // fn f; 2231 // @endcode 2232 2233 // Synthesize a parameter for each argument type. 2234 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2235 AE = FT->arg_type_end(); AI != AE; ++AI) { 2236 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2237 SourceLocation(), 0, 2238 *AI, VarDecl::None, 0); 2239 Param->setImplicit(); 2240 Params.push_back(Param); 2241 } 2242 } else { 2243 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2244 "Should not need args for typedef of non-prototype fn"); 2245 } 2246 // Finally, we know we have the right number of parameters, install them. 2247 NewFD->setParams(Context, Params.data(), Params.size()); 2248 2249 2250 2251 // If name lookup finds a previous declaration that is not in the 2252 // same scope as the new declaration, this may still be an 2253 // acceptable redeclaration. 2254 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2255 !(NewFD->hasLinkage() && 2256 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2257 PrevDecl = 0; 2258 2259 // Perform semantic checking on the function declaration. 2260 bool OverloadableAttrRequired = false; // FIXME: HACK! 2261 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2262 /*FIXME:*/OverloadableAttrRequired); 2263 2264 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2265 // An out-of-line member function declaration must also be a 2266 // definition (C++ [dcl.meaning]p1). 2267 if (!IsFunctionDefinition) { 2268 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2269 << D.getCXXScopeSpec().getRange(); 2270 NewFD->setInvalidDecl(); 2271 } else if (!Redeclaration) { 2272 // The user tried to provide an out-of-line definition for a 2273 // function that is a member of a class or namespace, but there 2274 // was no such member function declared (C++ [class.mfct]p2, 2275 // C++ [namespace.memdef]p2). For example: 2276 // 2277 // class X { 2278 // void f() const; 2279 // }; 2280 // 2281 // void X::f() { } // ill-formed 2282 // 2283 // Complain about this problem, and attempt to suggest close 2284 // matches (e.g., those that differ only in cv-qualifiers and 2285 // whether the parameter types are references). 2286 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2287 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2288 NewFD->setInvalidDecl(); 2289 2290 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2291 true); 2292 assert(!Prev.isAmbiguous() && 2293 "Cannot have an ambiguity in previous-declaration lookup"); 2294 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2295 Func != FuncEnd; ++Func) { 2296 if (isa<FunctionDecl>(*Func) && 2297 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2298 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2299 } 2300 2301 PrevDecl = 0; 2302 } 2303 } 2304 2305 // Handle attributes. We need to have merged decls when handling attributes 2306 // (for example to check for conflicts, etc). 2307 // FIXME: This needs to happen before we merge declarations. Then, 2308 // let attribute merging cope with attribute conflicts. 2309 ProcessDeclAttributes(NewFD, D); 2310 AddKnownFunctionAttributes(NewFD); 2311 2312 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2313 // If a function name is overloadable in C, then every function 2314 // with that name must be marked "overloadable". 2315 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2316 << Redeclaration << NewFD; 2317 if (PrevDecl) 2318 Diag(PrevDecl->getLocation(), 2319 diag::note_attribute_overloadable_prev_overload); 2320 NewFD->addAttr(::new (Context) OverloadableAttr()); 2321 } 2322 2323 // If this is a locally-scoped extern C function, update the 2324 // map of such names. 2325 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2326 && !NewFD->isInvalidDecl()) 2327 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2328 2329 return NewFD; 2330} 2331 2332/// \brief Perform semantic checking of a new function declaration. 2333/// 2334/// Performs semantic analysis of the new function declaration 2335/// NewFD. This routine performs all semantic checking that does not 2336/// require the actual declarator involved in the declaration, and is 2337/// used both for the declaration of functions as they are parsed 2338/// (called via ActOnDeclarator) and for the declaration of functions 2339/// that have been instantiated via C++ template instantiation (called 2340/// via InstantiateDecl). 2341/// 2342/// This sets NewFD->isInvalidDecl() to true if there was an error. 2343void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2344 bool &Redeclaration, 2345 bool &OverloadableAttrRequired) { 2346 // If NewFD is already known erroneous, don't do any of this checking. 2347 if (NewFD->isInvalidDecl()) 2348 return; 2349 2350 if (NewFD->getResultType()->isVariablyModifiedType()) { 2351 // Functions returning a variably modified type violate C99 6.7.5.2p2 2352 // because all functions have linkage. 2353 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2354 return NewFD->setInvalidDecl(); 2355 } 2356 2357 // Semantic checking for this function declaration (in isolation). 2358 if (getLangOptions().CPlusPlus) { 2359 // C++-specific checks. 2360 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2361 CheckConstructor(Constructor); 2362 } else if (isa<CXXDestructorDecl>(NewFD)) { 2363 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2364 Record->setUserDeclaredDestructor(true); 2365 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2366 // user-defined destructor. 2367 Record->setPOD(false); 2368 2369 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2370 // declared destructor. 2371 Record->setHasTrivialDestructor(false); 2372 } else if (CXXConversionDecl *Conversion 2373 = dyn_cast<CXXConversionDecl>(NewFD)) 2374 ActOnConversionDeclarator(Conversion); 2375 2376 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2377 if (NewFD->isOverloadedOperator() && 2378 CheckOverloadedOperatorDeclaration(NewFD)) 2379 return NewFD->setInvalidDecl(); 2380 } 2381 2382 // C99 6.7.4p6: 2383 // [... ] For a function with external linkage, the following 2384 // restrictions apply: [...] If all of the file scope declarations 2385 // for a function in a translation unit include the inline 2386 // function specifier without extern, then the definition in that 2387 // translation unit is an inline definition. An inline definition 2388 // does not provide an external definition for the function, and 2389 // does not forbid an external definition in another translation 2390 // unit. 2391 // 2392 // Here we determine whether this function, in isolation, would be a 2393 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2394 // previous declarations. 2395 if (NewFD->isInline() && getLangOptions().C99 && 2396 NewFD->getStorageClass() == FunctionDecl::None && 2397 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2398 NewFD->setC99InlineDefinition(true); 2399 2400 // Check for a previous declaration of this name. 2401 if (!PrevDecl && NewFD->isExternC(Context)) { 2402 // Since we did not find anything by this name and we're declaring 2403 // an extern "C" function, look for a non-visible extern "C" 2404 // declaration with the same name. 2405 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2406 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2407 if (Pos != LocallyScopedExternalDecls.end()) 2408 PrevDecl = Pos->second; 2409 } 2410 2411 // Merge or overload the declaration with an existing declaration of 2412 // the same name, if appropriate. 2413 if (PrevDecl) { 2414 // Determine whether NewFD is an overload of PrevDecl or 2415 // a declaration that requires merging. If it's an overload, 2416 // there's no more work to do here; we'll just add the new 2417 // function to the scope. 2418 OverloadedFunctionDecl::function_iterator MatchedDecl; 2419 2420 if (!getLangOptions().CPlusPlus && 2421 AllowOverloadingOfFunction(PrevDecl, Context)) { 2422 OverloadableAttrRequired = true; 2423 2424 // Functions marked "overloadable" must have a prototype (that 2425 // we can't get through declaration merging). 2426 if (!NewFD->getType()->getAsFunctionProtoType()) { 2427 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2428 << NewFD; 2429 Redeclaration = true; 2430 2431 // Turn this into a variadic function with no parameters. 2432 QualType R = Context.getFunctionType( 2433 NewFD->getType()->getAsFunctionType()->getResultType(), 2434 0, 0, true, 0); 2435 NewFD->setType(R); 2436 return NewFD->setInvalidDecl(); 2437 } 2438 } 2439 2440 if (PrevDecl && 2441 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2442 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2443 Redeclaration = true; 2444 Decl *OldDecl = PrevDecl; 2445 2446 // If PrevDecl was an overloaded function, extract the 2447 // FunctionDecl that matched. 2448 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2449 OldDecl = *MatchedDecl; 2450 2451 // NewFD and OldDecl represent declarations that need to be 2452 // merged. 2453 if (MergeFunctionDecl(NewFD, OldDecl)) 2454 return NewFD->setInvalidDecl(); 2455 2456 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2457 } 2458 } 2459 2460 // In C++, check default arguments now that we have merged decls. Unless 2461 // the lexical context is the class, because in this case this is done 2462 // during delayed parsing anyway. 2463 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2464 CheckCXXDefaultArguments(NewFD); 2465} 2466 2467bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2468 // FIXME: Need strict checking. In C89, we need to check for 2469 // any assignment, increment, decrement, function-calls, or 2470 // commas outside of a sizeof. In C99, it's the same list, 2471 // except that the aforementioned are allowed in unevaluated 2472 // expressions. Everything else falls under the 2473 // "may accept other forms of constant expressions" exception. 2474 // (We never end up here for C++, so the constant expression 2475 // rules there don't matter.) 2476 if (Init->isConstantInitializer(Context)) 2477 return false; 2478 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2479 << Init->getSourceRange(); 2480 return true; 2481} 2482 2483void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2484 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2485} 2486 2487/// AddInitializerToDecl - Adds the initializer Init to the 2488/// declaration dcl. If DirectInit is true, this is C++ direct 2489/// initialization rather than copy initialization. 2490void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2491 Decl *RealDecl = dcl.getAs<Decl>(); 2492 // If there is no declaration, there was an error parsing it. Just ignore 2493 // the initializer. 2494 if (RealDecl == 0) 2495 return; 2496 2497 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2498 // With declarators parsed the way they are, the parser cannot 2499 // distinguish between a normal initializer and a pure-specifier. 2500 // Thus this grotesque test. 2501 IntegerLiteral *IL; 2502 Expr *Init = static_cast<Expr *>(init.get()); 2503 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2504 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2505 if (Method->isVirtualAsWritten()) { 2506 Method->setPure(); 2507 2508 // A class is abstract if at least one function is pure virtual. 2509 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2510 } else if (!Method->isInvalidDecl()) { 2511 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2512 << Method->getDeclName() << Init->getSourceRange(); 2513 Method->setInvalidDecl(); 2514 } 2515 } else { 2516 Diag(Method->getLocation(), diag::err_member_function_initialization) 2517 << Method->getDeclName() << Init->getSourceRange(); 2518 Method->setInvalidDecl(); 2519 } 2520 return; 2521 } 2522 2523 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2524 if (!VDecl) { 2525 if (getLangOptions().CPlusPlus && 2526 RealDecl->getLexicalDeclContext()->isRecord() && 2527 isa<NamedDecl>(RealDecl)) 2528 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2529 << cast<NamedDecl>(RealDecl)->getDeclName(); 2530 else 2531 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2532 RealDecl->setInvalidDecl(); 2533 return; 2534 } 2535 2536 if (!VDecl->getType()->isArrayType() && 2537 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2538 diag::err_typecheck_decl_incomplete_type)) { 2539 RealDecl->setInvalidDecl(); 2540 return; 2541 } 2542 2543 const VarDecl *Def = 0; 2544 if (VDecl->getDefinition(Def)) { 2545 Diag(VDecl->getLocation(), diag::err_redefinition) 2546 << VDecl->getDeclName(); 2547 Diag(Def->getLocation(), diag::note_previous_definition); 2548 VDecl->setInvalidDecl(); 2549 return; 2550 } 2551 2552 // Take ownership of the expression, now that we're sure we have somewhere 2553 // to put it. 2554 Expr *Init = init.takeAs<Expr>(); 2555 assert(Init && "missing initializer"); 2556 2557 // Get the decls type and save a reference for later, since 2558 // CheckInitializerTypes may change it. 2559 QualType DclT = VDecl->getType(), SavT = DclT; 2560 if (VDecl->isBlockVarDecl()) { 2561 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2562 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2563 VDecl->setInvalidDecl(); 2564 } else if (!VDecl->isInvalidDecl()) { 2565 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2566 VDecl->getDeclName(), DirectInit, VDecl)) 2567 VDecl->setInvalidDecl(); 2568 2569 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2570 // Don't check invalid declarations to avoid emitting useless diagnostics. 2571 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2572 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2573 CheckForConstantInitializer(Init, DclT); 2574 } 2575 } 2576 } else if (VDecl->isStaticDataMember() && 2577 VDecl->getLexicalDeclContext()->isRecord()) { 2578 // This is an in-class initialization for a static data member, e.g., 2579 // 2580 // struct S { 2581 // static const int value = 17; 2582 // }; 2583 2584 // Attach the initializer 2585 VDecl->setInit(Context, Init); 2586 2587 // C++ [class.mem]p4: 2588 // A member-declarator can contain a constant-initializer only 2589 // if it declares a static member (9.4) of const integral or 2590 // const enumeration type, see 9.4.2. 2591 QualType T = VDecl->getType(); 2592 if (!T->isDependentType() && 2593 (!Context.getCanonicalType(T).isConstQualified() || 2594 !T->isIntegralType())) { 2595 Diag(VDecl->getLocation(), diag::err_member_initialization) 2596 << VDecl->getDeclName() << Init->getSourceRange(); 2597 VDecl->setInvalidDecl(); 2598 } else { 2599 // C++ [class.static.data]p4: 2600 // If a static data member is of const integral or const 2601 // enumeration type, its declaration in the class definition 2602 // can specify a constant-initializer which shall be an 2603 // integral constant expression (5.19). 2604 if (!Init->isTypeDependent() && 2605 !Init->getType()->isIntegralType()) { 2606 // We have a non-dependent, non-integral or enumeration type. 2607 Diag(Init->getSourceRange().getBegin(), 2608 diag::err_in_class_initializer_non_integral_type) 2609 << Init->getType() << Init->getSourceRange(); 2610 VDecl->setInvalidDecl(); 2611 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2612 // Check whether the expression is a constant expression. 2613 llvm::APSInt Value; 2614 SourceLocation Loc; 2615 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2616 Diag(Loc, diag::err_in_class_initializer_non_constant) 2617 << Init->getSourceRange(); 2618 VDecl->setInvalidDecl(); 2619 } else if (!VDecl->getType()->isDependentType()) 2620 ImpCastExprToType(Init, VDecl->getType()); 2621 } 2622 } 2623 } else if (VDecl->isFileVarDecl()) { 2624 if (VDecl->getStorageClass() == VarDecl::Extern) 2625 Diag(VDecl->getLocation(), diag::warn_extern_init); 2626 if (!VDecl->isInvalidDecl()) 2627 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2628 VDecl->getDeclName(), DirectInit)) 2629 VDecl->setInvalidDecl(); 2630 2631 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2632 // Don't check invalid declarations to avoid emitting useless diagnostics. 2633 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2634 // C99 6.7.8p4. All file scoped initializers need to be constant. 2635 CheckForConstantInitializer(Init, DclT); 2636 } 2637 } 2638 // If the type changed, it means we had an incomplete type that was 2639 // completed by the initializer. For example: 2640 // int ary[] = { 1, 3, 5 }; 2641 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2642 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2643 VDecl->setType(DclT); 2644 Init->setType(DclT); 2645 } 2646 2647 // Attach the initializer to the decl. 2648 VDecl->setInit(Context, Init); 2649 2650 // If the previous declaration of VDecl was a tentative definition, 2651 // remove it from the set of tentative definitions. 2652 if (VDecl->getPreviousDeclaration() && 2653 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2654 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2655 = TentativeDefinitions.find(VDecl->getDeclName()); 2656 assert(Pos != TentativeDefinitions.end() && 2657 "Unrecorded tentative definition?"); 2658 TentativeDefinitions.erase(Pos); 2659 } 2660 2661 return; 2662} 2663 2664void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2665 Decl *RealDecl = dcl.getAs<Decl>(); 2666 2667 // If there is no declaration, there was an error parsing it. Just ignore it. 2668 if (RealDecl == 0) 2669 return; 2670 2671 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2672 QualType Type = Var->getType(); 2673 2674 // Record tentative definitions. 2675 if (Var->isTentativeDefinition(Context)) 2676 TentativeDefinitions[Var->getDeclName()] = Var; 2677 2678 // C++ [dcl.init.ref]p3: 2679 // The initializer can be omitted for a reference only in a 2680 // parameter declaration (8.3.5), in the declaration of a 2681 // function return type, in the declaration of a class member 2682 // within its class declaration (9.2), and where the extern 2683 // specifier is explicitly used. 2684 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2685 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2686 << Var->getDeclName() 2687 << SourceRange(Var->getLocation(), Var->getLocation()); 2688 Var->setInvalidDecl(); 2689 return; 2690 } 2691 2692 // C++ [dcl.init]p9: 2693 // 2694 // If no initializer is specified for an object, and the object 2695 // is of (possibly cv-qualified) non-POD class type (or array 2696 // thereof), the object shall be default-initialized; if the 2697 // object is of const-qualified type, the underlying class type 2698 // shall have a user-declared default constructor. 2699 if (getLangOptions().CPlusPlus) { 2700 QualType InitType = Type; 2701 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2702 InitType = Array->getElementType(); 2703 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 2704 InitType->isRecordType()) { 2705 CXXRecordDecl *RD = 2706 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2707 CXXConstructorDecl *Constructor = 0; 2708 if (!RequireCompleteType(Var->getLocation(), InitType, 2709 diag::err_invalid_incomplete_type_use)) 2710 Constructor 2711 = PerformInitializationByConstructor(InitType, 0, 0, 2712 Var->getLocation(), 2713 SourceRange(Var->getLocation(), 2714 Var->getLocation()), 2715 Var->getDeclName(), 2716 IK_Default); 2717 if (!Constructor) 2718 Var->setInvalidDecl(); 2719 else if (!RD->hasTrivialConstructor()) 2720 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2721 } 2722 } 2723 2724#if 0 2725 // FIXME: Temporarily disabled because we are not properly parsing 2726 // linkage specifications on declarations, e.g., 2727 // 2728 // extern "C" const CGPoint CGPointerZero; 2729 // 2730 // C++ [dcl.init]p9: 2731 // 2732 // If no initializer is specified for an object, and the 2733 // object is of (possibly cv-qualified) non-POD class type (or 2734 // array thereof), the object shall be default-initialized; if 2735 // the object is of const-qualified type, the underlying class 2736 // type shall have a user-declared default 2737 // constructor. Otherwise, if no initializer is specified for 2738 // an object, the object and its subobjects, if any, have an 2739 // indeterminate initial value; if the object or any of its 2740 // subobjects are of const-qualified type, the program is 2741 // ill-formed. 2742 // 2743 // This isn't technically an error in C, so we don't diagnose it. 2744 // 2745 // FIXME: Actually perform the POD/user-defined default 2746 // constructor check. 2747 if (getLangOptions().CPlusPlus && 2748 Context.getCanonicalType(Type).isConstQualified() && 2749 !Var->hasExternalStorage()) 2750 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2751 << Var->getName() 2752 << SourceRange(Var->getLocation(), Var->getLocation()); 2753#endif 2754 } 2755} 2756 2757Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2758 unsigned NumDecls) { 2759 llvm::SmallVector<Decl*, 8> Decls; 2760 2761 for (unsigned i = 0; i != NumDecls; ++i) 2762 if (Decl *D = Group[i].getAs<Decl>()) 2763 Decls.push_back(D); 2764 2765 // Perform semantic analysis that depends on having fully processed both 2766 // the declarator and initializer. 2767 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2768 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2769 if (!IDecl) 2770 continue; 2771 QualType T = IDecl->getType(); 2772 2773 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2774 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2775 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2776 if (!IDecl->isInvalidDecl() && 2777 RequireCompleteType(IDecl->getLocation(), T, 2778 diag::err_typecheck_decl_incomplete_type)) 2779 IDecl->setInvalidDecl(); 2780 } 2781 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2782 // object that has file scope without an initializer, and without a 2783 // storage-class specifier or with the storage-class specifier "static", 2784 // constitutes a tentative definition. Note: A tentative definition with 2785 // external linkage is valid (C99 6.2.2p5). 2786 if (IDecl->isTentativeDefinition(Context)) { 2787 QualType CheckType = T; 2788 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2789 2790 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2791 if (ArrayT) { 2792 CheckType = ArrayT->getElementType(); 2793 DiagID = diag::err_illegal_decl_array_incomplete_type; 2794 } 2795 2796 if (IDecl->isInvalidDecl()) { 2797 // Do nothing with invalid declarations 2798 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2799 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2800 // C99 6.9.2p3: If the declaration of an identifier for an object is 2801 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2802 // declared type shall not be an incomplete type. 2803 IDecl->setInvalidDecl(); 2804 } 2805 } 2806 } 2807 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2808 Decls.data(), Decls.size())); 2809} 2810 2811 2812/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2813/// to introduce parameters into function prototype scope. 2814Sema::DeclPtrTy 2815Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2816 const DeclSpec &DS = D.getDeclSpec(); 2817 2818 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2819 VarDecl::StorageClass StorageClass = VarDecl::None; 2820 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2821 StorageClass = VarDecl::Register; 2822 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2823 Diag(DS.getStorageClassSpecLoc(), 2824 diag::err_invalid_storage_class_in_func_decl); 2825 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2826 } 2827 2828 if (D.getDeclSpec().isThreadSpecified()) 2829 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2830 2831 DiagnoseFunctionSpecifiers(D); 2832 2833 // Check that there are no default arguments inside the type of this 2834 // parameter (C++ only). 2835 if (getLangOptions().CPlusPlus) 2836 CheckExtraCXXDefaultArguments(D); 2837 2838 QualType parmDeclType = GetTypeForDeclarator(D, S); 2839 2840 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2841 // Can this happen for params? We already checked that they don't conflict 2842 // among each other. Here they can only shadow globals, which is ok. 2843 IdentifierInfo *II = D.getIdentifier(); 2844 if (II) { 2845 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2846 if (PrevDecl->isTemplateParameter()) { 2847 // Maybe we will complain about the shadowed template parameter. 2848 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2849 // Just pretend that we didn't see the previous declaration. 2850 PrevDecl = 0; 2851 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2852 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2853 2854 // Recover by removing the name 2855 II = 0; 2856 D.SetIdentifier(0, D.getIdentifierLoc()); 2857 } 2858 } 2859 } 2860 2861 // Parameters can not be abstract class types. 2862 // For record types, this is done by the AbstractClassUsageDiagnoser once 2863 // the class has been completely parsed. 2864 if (!CurContext->isRecord() && 2865 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2866 diag::err_abstract_type_in_decl, 2867 AbstractParamType)) 2868 D.setInvalidType(true); 2869 2870 QualType T = adjustParameterType(parmDeclType); 2871 2872 ParmVarDecl *New; 2873 if (T == parmDeclType) // parameter type did not need adjustment 2874 New = ParmVarDecl::Create(Context, CurContext, 2875 D.getIdentifierLoc(), II, 2876 parmDeclType, StorageClass, 2877 0); 2878 else // keep track of both the adjusted and unadjusted types 2879 New = OriginalParmVarDecl::Create(Context, CurContext, 2880 D.getIdentifierLoc(), II, T, 2881 parmDeclType, StorageClass, 0); 2882 2883 if (D.isInvalidType()) 2884 New->setInvalidDecl(); 2885 2886 // Parameter declarators cannot be interface types. All ObjC objects are 2887 // passed by reference. 2888 if (T->isObjCInterfaceType()) { 2889 Diag(D.getIdentifierLoc(), 2890 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2891 New->setInvalidDecl(); 2892 } 2893 2894 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2895 if (D.getCXXScopeSpec().isSet()) { 2896 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2897 << D.getCXXScopeSpec().getRange(); 2898 New->setInvalidDecl(); 2899 } 2900 2901 // Add the parameter declaration into this scope. 2902 S->AddDecl(DeclPtrTy::make(New)); 2903 if (II) 2904 IdResolver.AddDecl(New); 2905 2906 ProcessDeclAttributes(New, D); 2907 2908 if (New->hasAttr<BlocksAttr>()) { 2909 Diag(New->getLocation(), diag::err_block_on_nonlocal); 2910 } 2911 return DeclPtrTy::make(New); 2912} 2913 2914void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2915 SourceLocation LocAfterDecls) { 2916 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2917 "Not a function declarator!"); 2918 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2919 2920 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2921 // for a K&R function. 2922 if (!FTI.hasPrototype) { 2923 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2924 --i; 2925 if (FTI.ArgInfo[i].Param == 0) { 2926 std::string Code = " int "; 2927 Code += FTI.ArgInfo[i].Ident->getName(); 2928 Code += ";\n"; 2929 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2930 << FTI.ArgInfo[i].Ident 2931 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2932 2933 // Implicitly declare the argument as type 'int' for lack of a better 2934 // type. 2935 DeclSpec DS; 2936 const char* PrevSpec; // unused 2937 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2938 PrevSpec); 2939 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2940 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2941 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2942 } 2943 } 2944 } 2945} 2946 2947Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2948 Declarator &D) { 2949 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2950 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2951 "Not a function declarator!"); 2952 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2953 2954 if (FTI.hasPrototype) { 2955 // FIXME: Diagnose arguments without names in C. 2956 } 2957 2958 Scope *ParentScope = FnBodyScope->getParent(); 2959 2960 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2961 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2962} 2963 2964Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2965 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2966 2967 CurFunctionNeedsScopeChecking = false; 2968 2969 // See if this is a redefinition. 2970 const FunctionDecl *Definition; 2971 if (FD->getBody(Context, Definition)) { 2972 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2973 Diag(Definition->getLocation(), diag::note_previous_definition); 2974 } 2975 2976 // Builtin functions cannot be defined. 2977 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2978 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2979 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2980 FD->setInvalidDecl(); 2981 } 2982 } 2983 2984 // The return type of a function definition must be complete 2985 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2986 QualType ResultType = FD->getResultType(); 2987 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2988 !FD->isInvalidDecl() && 2989 RequireCompleteType(FD->getLocation(), ResultType, 2990 diag::err_func_def_incomplete_result)) 2991 FD->setInvalidDecl(); 2992 2993 // GNU warning -Wmissing-prototypes: 2994 // Warn if a global function is defined without a previous 2995 // prototype declaration. This warning is issued even if the 2996 // definition itself provides a prototype. The aim is to detect 2997 // global functions that fail to be declared in header files. 2998 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2999 !FD->isMain()) { 3000 bool MissingPrototype = true; 3001 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3002 Prev; Prev = Prev->getPreviousDeclaration()) { 3003 // Ignore any declarations that occur in function or method 3004 // scope, because they aren't visible from the header. 3005 if (Prev->getDeclContext()->isFunctionOrMethod()) 3006 continue; 3007 3008 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3009 break; 3010 } 3011 3012 if (MissingPrototype) 3013 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3014 } 3015 3016 if (FnBodyScope) 3017 PushDeclContext(FnBodyScope, FD); 3018 3019 // Check the validity of our function parameters 3020 CheckParmsForFunctionDef(FD); 3021 3022 // Introduce our parameters into the function scope 3023 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3024 ParmVarDecl *Param = FD->getParamDecl(p); 3025 Param->setOwningFunction(FD); 3026 3027 // If this has an identifier, add it to the scope stack. 3028 if (Param->getIdentifier() && FnBodyScope) 3029 PushOnScopeChains(Param, FnBodyScope); 3030 } 3031 3032 // Checking attributes of current function definition 3033 // dllimport attribute. 3034 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 3035 // dllimport attribute cannot be applied to definition. 3036 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3037 Diag(FD->getLocation(), 3038 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3039 << "dllimport"; 3040 FD->setInvalidDecl(); 3041 return DeclPtrTy::make(FD); 3042 } else { 3043 // If a symbol previously declared dllimport is later defined, the 3044 // attribute is ignored in subsequent references, and a warning is 3045 // emitted. 3046 Diag(FD->getLocation(), 3047 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3048 << FD->getNameAsCString() << "dllimport"; 3049 } 3050 } 3051 return DeclPtrTy::make(FD); 3052} 3053 3054Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3055 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3056} 3057 3058Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3059 bool IsInstantiation) { 3060 Decl *dcl = D.getAs<Decl>(); 3061 Stmt *Body = BodyArg.takeAs<Stmt>(); 3062 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3063 FD->setBody(Body); 3064 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3065 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3066 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3067 MD->setBody(Body); 3068 } else { 3069 Body->Destroy(Context); 3070 return DeclPtrTy(); 3071 } 3072 if (!IsInstantiation) 3073 PopDeclContext(); 3074 3075 // Verify and clean out per-function state. 3076 3077 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3078 3079 // Check goto/label use. 3080 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3081 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3082 LabelStmt *L = I->second; 3083 3084 // Verify that we have no forward references left. If so, there was a goto 3085 // or address of a label taken, but no definition of it. Label fwd 3086 // definitions are indicated with a null substmt. 3087 if (L->getSubStmt() != 0) 3088 continue; 3089 3090 // Emit error. 3091 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3092 3093 // At this point, we have gotos that use the bogus label. Stitch it into 3094 // the function body so that they aren't leaked and that the AST is well 3095 // formed. 3096 if (Body == 0) { 3097 // The whole function wasn't parsed correctly, just delete this. 3098 L->Destroy(Context); 3099 continue; 3100 } 3101 3102 // Otherwise, the body is valid: we want to stitch the label decl into the 3103 // function somewhere so that it is properly owned and so that the goto 3104 // has a valid target. Do this by creating a new compound stmt with the 3105 // label in it. 3106 3107 // Give the label a sub-statement. 3108 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3109 3110 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3111 cast<CXXTryStmt>(Body)->getTryBlock() : 3112 cast<CompoundStmt>(Body); 3113 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3114 Elements.push_back(L); 3115 Compound->setStmts(Context, &Elements[0], Elements.size()); 3116 } 3117 FunctionLabelMap.clear(); 3118 3119 if (!Body) return D; 3120 3121 // Verify that that gotos and switch cases don't jump into scopes illegally. 3122 if (CurFunctionNeedsScopeChecking) 3123 DiagnoseInvalidJumps(Body); 3124 3125 // C++ constructors that have function-try-blocks can't have return statements 3126 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3127 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3128 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3129 3130 return D; 3131} 3132 3133/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3134/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3135NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3136 IdentifierInfo &II, Scope *S) { 3137 // Before we produce a declaration for an implicitly defined 3138 // function, see whether there was a locally-scoped declaration of 3139 // this name as a function or variable. If so, use that 3140 // (non-visible) declaration, and complain about it. 3141 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3142 = LocallyScopedExternalDecls.find(&II); 3143 if (Pos != LocallyScopedExternalDecls.end()) { 3144 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3145 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3146 return Pos->second; 3147 } 3148 3149 // Extension in C99. Legal in C90, but warn about it. 3150 if (getLangOptions().C99) 3151 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3152 else 3153 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3154 3155 // FIXME: handle stuff like: 3156 // void foo() { extern float X(); } 3157 // void bar() { X(); } <-- implicit decl for X in another scope. 3158 3159 // Set a Declarator for the implicit definition: int foo(); 3160 const char *Dummy; 3161 DeclSpec DS; 3162 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3163 Error = Error; // Silence warning. 3164 assert(!Error && "Error setting up implicit decl!"); 3165 Declarator D(DS, Declarator::BlockContext); 3166 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3167 0, 0, false, false, 0, 0, Loc, D), 3168 SourceLocation()); 3169 D.SetIdentifier(&II, Loc); 3170 3171 // Insert this function into translation-unit scope. 3172 3173 DeclContext *PrevDC = CurContext; 3174 CurContext = Context.getTranslationUnitDecl(); 3175 3176 FunctionDecl *FD = 3177 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3178 FD->setImplicit(); 3179 3180 CurContext = PrevDC; 3181 3182 AddKnownFunctionAttributes(FD); 3183 3184 return FD; 3185} 3186 3187/// \brief Adds any function attributes that we know a priori based on 3188/// the declaration of this function. 3189/// 3190/// These attributes can apply both to implicitly-declared builtins 3191/// (like __builtin___printf_chk) or to library-declared functions 3192/// like NSLog or printf. 3193void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3194 if (FD->isInvalidDecl()) 3195 return; 3196 3197 // If this is a built-in function, map its builtin attributes to 3198 // actual attributes. 3199 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3200 // Handle printf-formatting attributes. 3201 unsigned FormatIdx; 3202 bool HasVAListArg; 3203 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3204 if (!FD->getAttr<FormatAttr>()) 3205 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3206 FormatIdx + 2)); 3207 } 3208 3209 // Mark const if we don't care about errno and that is the only 3210 // thing preventing the function from being const. This allows 3211 // IRgen to use LLVM intrinsics for such functions. 3212 if (!getLangOptions().MathErrno && 3213 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3214 if (!FD->getAttr<ConstAttr>()) 3215 FD->addAttr(::new (Context) ConstAttr()); 3216 } 3217 } 3218 3219 IdentifierInfo *Name = FD->getIdentifier(); 3220 if (!Name) 3221 return; 3222 if ((!getLangOptions().CPlusPlus && 3223 FD->getDeclContext()->isTranslationUnit()) || 3224 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3225 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3226 LinkageSpecDecl::lang_c)) { 3227 // Okay: this could be a libc/libm/Objective-C function we know 3228 // about. 3229 } else 3230 return; 3231 3232 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3233 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3234 // FIXME: We known better than our headers. 3235 const_cast<FormatAttr *>(Format)->setType("printf"); 3236 } else 3237 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3238 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3239 if (!FD->getAttr<FormatAttr>()) 3240 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3241 } 3242} 3243 3244TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3245 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3246 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3247 3248 // Scope manipulation handled by caller. 3249 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3250 D.getIdentifierLoc(), 3251 D.getIdentifier(), 3252 T); 3253 3254 if (TagType *TT = dyn_cast<TagType>(T)) { 3255 TagDecl *TD = TT->getDecl(); 3256 3257 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3258 // keep track of the TypedefDecl. 3259 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3260 TD->setTypedefForAnonDecl(NewTD); 3261 } 3262 3263 if (D.isInvalidType()) 3264 NewTD->setInvalidDecl(); 3265 return NewTD; 3266} 3267 3268 3269/// \brief Determine whether a tag with a given kind is acceptable 3270/// as a redeclaration of the given tag declaration. 3271/// 3272/// \returns true if the new tag kind is acceptable, false otherwise. 3273bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3274 TagDecl::TagKind NewTag, 3275 SourceLocation NewTagLoc, 3276 const IdentifierInfo &Name) { 3277 // C++ [dcl.type.elab]p3: 3278 // The class-key or enum keyword present in the 3279 // elaborated-type-specifier shall agree in kind with the 3280 // declaration to which the name in theelaborated-type-specifier 3281 // refers. This rule also applies to the form of 3282 // elaborated-type-specifier that declares a class-name or 3283 // friend class since it can be construed as referring to the 3284 // definition of the class. Thus, in any 3285 // elaborated-type-specifier, the enum keyword shall be used to 3286 // refer to an enumeration (7.2), the union class-keyshall be 3287 // used to refer to a union (clause 9), and either the class or 3288 // struct class-key shall be used to refer to a class (clause 9) 3289 // declared using the class or struct class-key. 3290 TagDecl::TagKind OldTag = Previous->getTagKind(); 3291 if (OldTag == NewTag) 3292 return true; 3293 3294 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3295 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3296 // Warn about the struct/class tag mismatch. 3297 bool isTemplate = false; 3298 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3299 isTemplate = Record->getDescribedClassTemplate(); 3300 3301 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3302 << (NewTag == TagDecl::TK_class) 3303 << isTemplate << &Name 3304 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3305 OldTag == TagDecl::TK_class? "class" : "struct"); 3306 Diag(Previous->getLocation(), diag::note_previous_use); 3307 return true; 3308 } 3309 return false; 3310} 3311 3312/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3313/// former case, Name will be non-null. In the later case, Name will be null. 3314/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3315/// reference/declaration/definition of a tag. 3316Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3317 SourceLocation KWLoc, const CXXScopeSpec &SS, 3318 IdentifierInfo *Name, SourceLocation NameLoc, 3319 AttributeList *Attr, AccessSpecifier AS) { 3320 // If this is not a definition, it must have a name. 3321 assert((Name != 0 || TK == TK_Definition) && 3322 "Nameless record must be a definition!"); 3323 3324 TagDecl::TagKind Kind; 3325 switch (TagSpec) { 3326 default: assert(0 && "Unknown tag type!"); 3327 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3328 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3329 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3330 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3331 } 3332 3333 DeclContext *SearchDC = CurContext; 3334 DeclContext *DC = CurContext; 3335 NamedDecl *PrevDecl = 0; 3336 3337 bool Invalid = false; 3338 3339 if (Name && SS.isNotEmpty()) { 3340 // We have a nested-name tag ('struct foo::bar'). 3341 3342 // Check for invalid 'foo::'. 3343 if (SS.isInvalid()) { 3344 Name = 0; 3345 goto CreateNewDecl; 3346 } 3347 3348 if (RequireCompleteDeclContext(SS)) 3349 return DeclPtrTy::make((Decl *)0); 3350 3351 DC = computeDeclContext(SS); 3352 SearchDC = DC; 3353 // Look-up name inside 'foo::'. 3354 PrevDecl 3355 = dyn_cast_or_null<TagDecl>( 3356 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3357 3358 // A tag 'foo::bar' must already exist. 3359 if (PrevDecl == 0) { 3360 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3361 Name = 0; 3362 Invalid = true; 3363 goto CreateNewDecl; 3364 } 3365 } else if (Name) { 3366 // If this is a named struct, check to see if there was a previous forward 3367 // declaration or definition. 3368 // FIXME: We're looking into outer scopes here, even when we 3369 // shouldn't be. Doing so can result in ambiguities that we 3370 // shouldn't be diagnosing. 3371 LookupResult R = LookupName(S, Name, LookupTagName, 3372 /*RedeclarationOnly=*/(TK != TK_Reference)); 3373 if (R.isAmbiguous()) { 3374 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3375 // FIXME: This is not best way to recover from case like: 3376 // 3377 // struct S s; 3378 // 3379 // causes needless "incomplete type" error later. 3380 Name = 0; 3381 PrevDecl = 0; 3382 Invalid = true; 3383 } 3384 else 3385 PrevDecl = R; 3386 3387 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3388 // FIXME: This makes sure that we ignore the contexts associated 3389 // with C structs, unions, and enums when looking for a matching 3390 // tag declaration or definition. See the similar lookup tweak 3391 // in Sema::LookupName; is there a better way to deal with this? 3392 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3393 SearchDC = SearchDC->getParent(); 3394 } 3395 } 3396 3397 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3398 // Maybe we will complain about the shadowed template parameter. 3399 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3400 // Just pretend that we didn't see the previous declaration. 3401 PrevDecl = 0; 3402 } 3403 3404 if (PrevDecl) { 3405 // Check whether the previous declaration is usable. 3406 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3407 3408 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3409 // If this is a use of a previous tag, or if the tag is already declared 3410 // in the same scope (so that the definition/declaration completes or 3411 // rementions the tag), reuse the decl. 3412 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3413 // Make sure that this wasn't declared as an enum and now used as a 3414 // struct or something similar. 3415 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3416 bool SafeToContinue 3417 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3418 Kind != TagDecl::TK_enum); 3419 if (SafeToContinue) 3420 Diag(KWLoc, diag::err_use_with_wrong_tag) 3421 << Name 3422 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3423 PrevTagDecl->getKindName()); 3424 else 3425 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3426 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3427 3428 if (SafeToContinue) 3429 Kind = PrevTagDecl->getTagKind(); 3430 else { 3431 // Recover by making this an anonymous redefinition. 3432 Name = 0; 3433 PrevDecl = 0; 3434 Invalid = true; 3435 } 3436 } 3437 3438 if (!Invalid) { 3439 // If this is a use, just return the declaration we found. 3440 3441 // FIXME: In the future, return a variant or some other clue 3442 // for the consumer of this Decl to know it doesn't own it. 3443 // For our current ASTs this shouldn't be a problem, but will 3444 // need to be changed with DeclGroups. 3445 if (TK == TK_Reference) 3446 return DeclPtrTy::make(PrevDecl); 3447 3448 // Diagnose attempts to redefine a tag. 3449 if (TK == TK_Definition) { 3450 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3451 Diag(NameLoc, diag::err_redefinition) << Name; 3452 Diag(Def->getLocation(), diag::note_previous_definition); 3453 // If this is a redefinition, recover by making this 3454 // struct be anonymous, which will make any later 3455 // references get the previous definition. 3456 Name = 0; 3457 PrevDecl = 0; 3458 Invalid = true; 3459 } else { 3460 // If the type is currently being defined, complain 3461 // about a nested redefinition. 3462 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3463 if (Tag->isBeingDefined()) { 3464 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3465 Diag(PrevTagDecl->getLocation(), 3466 diag::note_previous_definition); 3467 Name = 0; 3468 PrevDecl = 0; 3469 Invalid = true; 3470 } 3471 } 3472 3473 // Okay, this is definition of a previously declared or referenced 3474 // tag PrevDecl. We're going to create a new Decl for it. 3475 } 3476 } 3477 // If we get here we have (another) forward declaration or we 3478 // have a definition. Just create a new decl. 3479 } else { 3480 // If we get here, this is a definition of a new tag type in a nested 3481 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3482 // new decl/type. We set PrevDecl to NULL so that the entities 3483 // have distinct types. 3484 PrevDecl = 0; 3485 } 3486 // If we get here, we're going to create a new Decl. If PrevDecl 3487 // is non-NULL, it's a definition of the tag declared by 3488 // PrevDecl. If it's NULL, we have a new definition. 3489 } else { 3490 // PrevDecl is a namespace, template, or anything else 3491 // that lives in the IDNS_Tag identifier namespace. 3492 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3493 // The tag name clashes with a namespace name, issue an error and 3494 // recover by making this tag be anonymous. 3495 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3496 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3497 Name = 0; 3498 PrevDecl = 0; 3499 Invalid = true; 3500 } else { 3501 // The existing declaration isn't relevant to us; we're in a 3502 // new scope, so clear out the previous declaration. 3503 PrevDecl = 0; 3504 } 3505 } 3506 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3507 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3508 // C++ [basic.scope.pdecl]p5: 3509 // -- for an elaborated-type-specifier of the form 3510 // 3511 // class-key identifier 3512 // 3513 // if the elaborated-type-specifier is used in the 3514 // decl-specifier-seq or parameter-declaration-clause of a 3515 // function defined in namespace scope, the identifier is 3516 // declared as a class-name in the namespace that contains 3517 // the declaration; otherwise, except as a friend 3518 // declaration, the identifier is declared in the smallest 3519 // non-class, non-function-prototype scope that contains the 3520 // declaration. 3521 // 3522 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3523 // C structs and unions. 3524 // 3525 // GNU C also supports this behavior as part of its incomplete 3526 // enum types extension, while GNU C++ does not. 3527 // 3528 // Find the context where we'll be declaring the tag. 3529 // FIXME: We would like to maintain the current DeclContext as the 3530 // lexical context, 3531 while (SearchDC->isRecord()) 3532 SearchDC = SearchDC->getParent(); 3533 3534 // Find the scope where we'll be declaring the tag. 3535 while (S->isClassScope() || 3536 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3537 ((S->getFlags() & Scope::DeclScope) == 0) || 3538 (S->getEntity() && 3539 ((DeclContext *)S->getEntity())->isTransparentContext())) 3540 S = S->getParent(); 3541 } 3542 3543CreateNewDecl: 3544 3545 // If there is an identifier, use the location of the identifier as the 3546 // location of the decl, otherwise use the location of the struct/union 3547 // keyword. 3548 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3549 3550 // Otherwise, create a new declaration. If there is a previous 3551 // declaration of the same entity, the two will be linked via 3552 // PrevDecl. 3553 TagDecl *New; 3554 3555 if (Kind == TagDecl::TK_enum) { 3556 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3557 // enum X { A, B, C } D; D should chain to X. 3558 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3559 cast_or_null<EnumDecl>(PrevDecl)); 3560 // If this is an undefined enum, warn. 3561 if (TK != TK_Definition && !Invalid) { 3562 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3563 : diag::ext_forward_ref_enum; 3564 Diag(Loc, DK); 3565 } 3566 } else { 3567 // struct/union/class 3568 3569 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3570 // struct X { int A; } D; D should chain to X. 3571 if (getLangOptions().CPlusPlus) 3572 // FIXME: Look for a way to use RecordDecl for simple structs. 3573 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3574 cast_or_null<CXXRecordDecl>(PrevDecl)); 3575 else 3576 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3577 cast_or_null<RecordDecl>(PrevDecl)); 3578 } 3579 3580 if (Kind != TagDecl::TK_enum) { 3581 // Handle #pragma pack: if the #pragma pack stack has non-default 3582 // alignment, make up a packed attribute for this decl. These 3583 // attributes are checked when the ASTContext lays out the 3584 // structure. 3585 // 3586 // It is important for implementing the correct semantics that this 3587 // happen here (in act on tag decl). The #pragma pack stack is 3588 // maintained as a result of parser callbacks which can occur at 3589 // many points during the parsing of a struct declaration (because 3590 // the #pragma tokens are effectively skipped over during the 3591 // parsing of the struct). 3592 if (unsigned Alignment = getPragmaPackAlignment()) 3593 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3594 } 3595 3596 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3597 // C++ [dcl.typedef]p3: 3598 // [...] Similarly, in a given scope, a class or enumeration 3599 // shall not be declared with the same name as a typedef-name 3600 // that is declared in that scope and refers to a type other 3601 // than the class or enumeration itself. 3602 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3603 TypedefDecl *PrevTypedef = 0; 3604 if (Lookup.getKind() == LookupResult::Found) 3605 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3606 3607 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3608 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3609 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3610 Diag(Loc, diag::err_tag_definition_of_typedef) 3611 << Context.getTypeDeclType(New) 3612 << PrevTypedef->getUnderlyingType(); 3613 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3614 Invalid = true; 3615 } 3616 } 3617 3618 if (Invalid) 3619 New->setInvalidDecl(); 3620 3621 if (Attr) 3622 ProcessDeclAttributeList(New, Attr); 3623 3624 // If we're declaring or defining a tag in function prototype scope 3625 // in C, note that this type can only be used within the function. 3626 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3627 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3628 3629 // Set the lexical context. If the tag has a C++ scope specifier, the 3630 // lexical context will be different from the semantic context. 3631 New->setLexicalDeclContext(CurContext); 3632 3633 // Set the access specifier. 3634 if (!Invalid) 3635 SetMemberAccessSpecifier(New, PrevDecl, AS); 3636 3637 if (TK == TK_Definition) 3638 New->startDefinition(); 3639 3640 // If this has an identifier, add it to the scope stack. 3641 if (Name) { 3642 S = getNonFieldDeclScope(S); 3643 PushOnScopeChains(New, S); 3644 } else { 3645 CurContext->addDecl(Context, New); 3646 } 3647 3648 return DeclPtrTy::make(New); 3649} 3650 3651void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3652 AdjustDeclIfTemplate(TagD); 3653 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3654 3655 // Enter the tag context. 3656 PushDeclContext(S, Tag); 3657 3658 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3659 FieldCollector->StartClass(); 3660 3661 if (Record->getIdentifier()) { 3662 // C++ [class]p2: 3663 // [...] The class-name is also inserted into the scope of the 3664 // class itself; this is known as the injected-class-name. For 3665 // purposes of access checking, the injected-class-name is treated 3666 // as if it were a public member name. 3667 CXXRecordDecl *InjectedClassName 3668 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3669 CurContext, Record->getLocation(), 3670 Record->getIdentifier(), Record); 3671 InjectedClassName->setImplicit(); 3672 InjectedClassName->setAccess(AS_public); 3673 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3674 InjectedClassName->setDescribedClassTemplate(Template); 3675 PushOnScopeChains(InjectedClassName, S); 3676 assert(InjectedClassName->isInjectedClassName() && 3677 "Broken injected-class-name"); 3678 } 3679 } 3680} 3681 3682void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3683 AdjustDeclIfTemplate(TagD); 3684 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3685 3686 if (isa<CXXRecordDecl>(Tag)) 3687 FieldCollector->FinishClass(); 3688 3689 // Exit this scope of this tag's definition. 3690 PopDeclContext(); 3691 3692 // Notify the consumer that we've defined a tag. 3693 Consumer.HandleTagDeclDefinition(Tag); 3694} 3695 3696// Note that FieldName may be null for anonymous bitfields. 3697bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3698 QualType FieldTy, const Expr *BitWidth) { 3699 3700 // C99 6.7.2.1p4 - verify the field type. 3701 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3702 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3703 // Handle incomplete types with specific error. 3704 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3705 return true; 3706 if (FieldName) 3707 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3708 << FieldName << FieldTy << BitWidth->getSourceRange(); 3709 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3710 << FieldTy << BitWidth->getSourceRange(); 3711 } 3712 3713 // If the bit-width is type- or value-dependent, don't try to check 3714 // it now. 3715 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3716 return false; 3717 3718 llvm::APSInt Value; 3719 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3720 return true; 3721 3722 // Zero-width bitfield is ok for anonymous field. 3723 if (Value == 0 && FieldName) 3724 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3725 3726 if (Value.isSigned() && Value.isNegative()) { 3727 if (FieldName) 3728 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3729 << FieldName << Value.toString(10); 3730 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3731 << Value.toString(10); 3732 } 3733 3734 if (!FieldTy->isDependentType()) { 3735 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3736 if (Value.getZExtValue() > TypeSize) { 3737 if (FieldName) 3738 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3739 << FieldName << (unsigned)TypeSize; 3740 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3741 << (unsigned)TypeSize; 3742 } 3743 } 3744 3745 return false; 3746} 3747 3748/// ActOnField - Each field of a struct/union/class is passed into this in order 3749/// to create a FieldDecl object for it. 3750Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3751 SourceLocation DeclStart, 3752 Declarator &D, ExprTy *BitfieldWidth) { 3753 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3754 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3755 AS_public); 3756 return DeclPtrTy::make(Res); 3757} 3758 3759/// HandleField - Analyze a field of a C struct or a C++ data member. 3760/// 3761FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3762 SourceLocation DeclStart, 3763 Declarator &D, Expr *BitWidth, 3764 AccessSpecifier AS) { 3765 IdentifierInfo *II = D.getIdentifier(); 3766 SourceLocation Loc = DeclStart; 3767 if (II) Loc = D.getIdentifierLoc(); 3768 3769 QualType T = GetTypeForDeclarator(D, S); 3770 if (getLangOptions().CPlusPlus) 3771 CheckExtraCXXDefaultArguments(D); 3772 3773 DiagnoseFunctionSpecifiers(D); 3774 3775 if (D.getDeclSpec().isThreadSpecified()) 3776 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3777 3778 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3779 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3780 PrevDecl = 0; 3781 3782 FieldDecl *NewFD 3783 = CheckFieldDecl(II, T, Record, Loc, 3784 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3785 BitWidth, AS, PrevDecl, &D); 3786 if (NewFD->isInvalidDecl() && PrevDecl) { 3787 // Don't introduce NewFD into scope; there's already something 3788 // with the same name in the same scope. 3789 } else if (II) { 3790 PushOnScopeChains(NewFD, S); 3791 } else 3792 Record->addDecl(Context, NewFD); 3793 3794 return NewFD; 3795} 3796 3797/// \brief Build a new FieldDecl and check its well-formedness. 3798/// 3799/// This routine builds a new FieldDecl given the fields name, type, 3800/// record, etc. \p PrevDecl should refer to any previous declaration 3801/// with the same name and in the same scope as the field to be 3802/// created. 3803/// 3804/// \returns a new FieldDecl. 3805/// 3806/// \todo The Declarator argument is a hack. It will be removed once 3807FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3808 RecordDecl *Record, SourceLocation Loc, 3809 bool Mutable, Expr *BitWidth, 3810 AccessSpecifier AS, NamedDecl *PrevDecl, 3811 Declarator *D) { 3812 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3813 bool InvalidDecl = false; 3814 if (D) InvalidDecl = D->isInvalidType(); 3815 3816 // If we receive a broken type, recover by assuming 'int' and 3817 // marking this declaration as invalid. 3818 if (T.isNull()) { 3819 InvalidDecl = true; 3820 T = Context.IntTy; 3821 } 3822 3823 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3824 // than a variably modified type. 3825 if (T->isVariablyModifiedType()) { 3826 bool SizeIsNegative; 3827 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3828 SizeIsNegative); 3829 if (!FixedTy.isNull()) { 3830 Diag(Loc, diag::warn_illegal_constant_array_size); 3831 T = FixedTy; 3832 } else { 3833 if (SizeIsNegative) 3834 Diag(Loc, diag::err_typecheck_negative_array_size); 3835 else 3836 Diag(Loc, diag::err_typecheck_field_variable_size); 3837 T = Context.IntTy; 3838 InvalidDecl = true; 3839 } 3840 } 3841 3842 // Fields can not have abstract class types 3843 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3844 AbstractFieldType)) 3845 InvalidDecl = true; 3846 3847 // If this is declared as a bit-field, check the bit-field. 3848 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3849 InvalidDecl = true; 3850 DeleteExpr(BitWidth); 3851 BitWidth = 0; 3852 } 3853 3854 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3855 Mutable); 3856 if (InvalidDecl) 3857 NewFD->setInvalidDecl(); 3858 3859 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3860 Diag(Loc, diag::err_duplicate_member) << II; 3861 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3862 NewFD->setInvalidDecl(); 3863 } 3864 3865 if (getLangOptions().CPlusPlus && !T->isPODType()) 3866 cast<CXXRecordDecl>(Record)->setPOD(false); 3867 3868 // FIXME: We need to pass in the attributes given an AST 3869 // representation, not a parser representation. 3870 if (D) 3871 ProcessDeclAttributes(NewFD, *D); 3872 3873 if (T.isObjCGCWeak()) 3874 Diag(Loc, diag::warn_attribute_weak_on_field); 3875 3876 NewFD->setAccess(AS); 3877 3878 // C++ [dcl.init.aggr]p1: 3879 // An aggregate is an array or a class (clause 9) with [...] no 3880 // private or protected non-static data members (clause 11). 3881 // A POD must be an aggregate. 3882 if (getLangOptions().CPlusPlus && 3883 (AS == AS_private || AS == AS_protected)) { 3884 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3885 CXXRecord->setAggregate(false); 3886 CXXRecord->setPOD(false); 3887 } 3888 3889 return NewFD; 3890} 3891 3892/// TranslateIvarVisibility - Translate visibility from a token ID to an 3893/// AST enum value. 3894static ObjCIvarDecl::AccessControl 3895TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3896 switch (ivarVisibility) { 3897 default: assert(0 && "Unknown visitibility kind"); 3898 case tok::objc_private: return ObjCIvarDecl::Private; 3899 case tok::objc_public: return ObjCIvarDecl::Public; 3900 case tok::objc_protected: return ObjCIvarDecl::Protected; 3901 case tok::objc_package: return ObjCIvarDecl::Package; 3902 } 3903} 3904 3905/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3906/// in order to create an IvarDecl object for it. 3907Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3908 SourceLocation DeclStart, 3909 Declarator &D, ExprTy *BitfieldWidth, 3910 tok::ObjCKeywordKind Visibility) { 3911 3912 IdentifierInfo *II = D.getIdentifier(); 3913 Expr *BitWidth = (Expr*)BitfieldWidth; 3914 SourceLocation Loc = DeclStart; 3915 if (II) Loc = D.getIdentifierLoc(); 3916 3917 // FIXME: Unnamed fields can be handled in various different ways, for 3918 // example, unnamed unions inject all members into the struct namespace! 3919 3920 QualType T = GetTypeForDeclarator(D, S); 3921 3922 if (BitWidth) { 3923 // 6.7.2.1p3, 6.7.2.1p4 3924 if (VerifyBitField(Loc, II, T, BitWidth)) { 3925 D.setInvalidType(); 3926 DeleteExpr(BitWidth); 3927 BitWidth = 0; 3928 } 3929 } else { 3930 // Not a bitfield. 3931 3932 // validate II. 3933 3934 } 3935 3936 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3937 // than a variably modified type. 3938 if (T->isVariablyModifiedType()) { 3939 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3940 D.setInvalidType(); 3941 } 3942 3943 // Get the visibility (access control) for this ivar. 3944 ObjCIvarDecl::AccessControl ac = 3945 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3946 : ObjCIvarDecl::None; 3947 3948 // Construct the decl. 3949 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3950 (Expr *)BitfieldWidth); 3951 3952 if (II) { 3953 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3954 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3955 && !isa<TagDecl>(PrevDecl)) { 3956 Diag(Loc, diag::err_duplicate_member) << II; 3957 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3958 NewID->setInvalidDecl(); 3959 } 3960 } 3961 3962 // Process attributes attached to the ivar. 3963 ProcessDeclAttributes(NewID, D); 3964 3965 if (D.isInvalidType()) 3966 NewID->setInvalidDecl(); 3967 3968 if (II) { 3969 // FIXME: When interfaces are DeclContexts, we'll need to add 3970 // these to the interface. 3971 S->AddDecl(DeclPtrTy::make(NewID)); 3972 IdResolver.AddDecl(NewID); 3973 } 3974 3975 return DeclPtrTy::make(NewID); 3976} 3977 3978void Sema::ActOnFields(Scope* S, 3979 SourceLocation RecLoc, DeclPtrTy RecDecl, 3980 DeclPtrTy *Fields, unsigned NumFields, 3981 SourceLocation LBrac, SourceLocation RBrac, 3982 AttributeList *Attr) { 3983 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3984 assert(EnclosingDecl && "missing record or interface decl"); 3985 3986 // If the decl this is being inserted into is invalid, then it may be a 3987 // redeclaration or some other bogus case. Don't try to add fields to it. 3988 if (EnclosingDecl->isInvalidDecl()) { 3989 // FIXME: Deallocate fields? 3990 return; 3991 } 3992 3993 3994 // Verify that all the fields are okay. 3995 unsigned NumNamedMembers = 0; 3996 llvm::SmallVector<FieldDecl*, 32> RecFields; 3997 3998 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3999 for (unsigned i = 0; i != NumFields; ++i) { 4000 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4001 4002 // Get the type for the field. 4003 Type *FDTy = FD->getType().getTypePtr(); 4004 4005 if (!FD->isAnonymousStructOrUnion()) { 4006 // Remember all fields written by the user. 4007 RecFields.push_back(FD); 4008 } 4009 4010 // If the field is already invalid for some reason, don't emit more 4011 // diagnostics about it. 4012 if (FD->isInvalidDecl()) 4013 continue; 4014 4015 // C99 6.7.2.1p2: 4016 // A structure or union shall not contain a member with 4017 // incomplete or function type (hence, a structure shall not 4018 // contain an instance of itself, but may contain a pointer to 4019 // an instance of itself), except that the last member of a 4020 // structure with more than one named member may have incomplete 4021 // array type; such a structure (and any union containing, 4022 // possibly recursively, a member that is such a structure) 4023 // shall not be a member of a structure or an element of an 4024 // array. 4025 if (FDTy->isFunctionType()) { 4026 // Field declared as a function. 4027 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4028 << FD->getDeclName(); 4029 FD->setInvalidDecl(); 4030 EnclosingDecl->setInvalidDecl(); 4031 continue; 4032 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4033 Record && Record->isStruct()) { 4034 // Flexible array member. 4035 if (NumNamedMembers < 1) { 4036 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4037 << FD->getDeclName(); 4038 FD->setInvalidDecl(); 4039 EnclosingDecl->setInvalidDecl(); 4040 continue; 4041 } 4042 // Okay, we have a legal flexible array member at the end of the struct. 4043 if (Record) 4044 Record->setHasFlexibleArrayMember(true); 4045 } else if (!FDTy->isDependentType() && 4046 RequireCompleteType(FD->getLocation(), FD->getType(), 4047 diag::err_field_incomplete)) { 4048 // Incomplete type 4049 FD->setInvalidDecl(); 4050 EnclosingDecl->setInvalidDecl(); 4051 continue; 4052 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4053 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4054 // If this is a member of a union, then entire union becomes "flexible". 4055 if (Record && Record->isUnion()) { 4056 Record->setHasFlexibleArrayMember(true); 4057 } else { 4058 // If this is a struct/class and this is not the last element, reject 4059 // it. Note that GCC supports variable sized arrays in the middle of 4060 // structures. 4061 if (i != NumFields-1) 4062 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4063 << FD->getDeclName() << FD->getType(); 4064 else { 4065 // We support flexible arrays at the end of structs in 4066 // other structs as an extension. 4067 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4068 << FD->getDeclName(); 4069 if (Record) 4070 Record->setHasFlexibleArrayMember(true); 4071 } 4072 } 4073 } 4074 } else if (FDTy->isObjCInterfaceType()) { 4075 /// A field cannot be an Objective-c object 4076 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4077 FD->setInvalidDecl(); 4078 EnclosingDecl->setInvalidDecl(); 4079 continue; 4080 } 4081 // Keep track of the number of named members. 4082 if (FD->getIdentifier()) 4083 ++NumNamedMembers; 4084 } 4085 4086 // Okay, we successfully defined 'Record'. 4087 if (Record) { 4088 Record->completeDefinition(Context); 4089 } else { 4090 ObjCIvarDecl **ClsFields = 4091 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4092 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4093 ID->setIVarList(ClsFields, RecFields.size(), Context); 4094 ID->setLocEnd(RBrac); 4095 4096 // Must enforce the rule that ivars in the base classes may not be 4097 // duplicates. 4098 if (ID->getSuperClass()) { 4099 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4100 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4101 ObjCIvarDecl* Ivar = (*IVI); 4102 4103 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4104 ObjCIvarDecl* prevIvar = 4105 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4106 if (prevIvar) { 4107 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4108 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4109 } 4110 } 4111 } 4112 } 4113 } else if (ObjCImplementationDecl *IMPDecl = 4114 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4115 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4116 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 4117 // FIXME: Set the DeclContext correctly when we build the 4118 // declarations. 4119 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4120 IMPDecl->addDecl(Context, ClsFields[I]); 4121 } 4122 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4123 } 4124 } 4125 4126 if (Attr) 4127 ProcessDeclAttributeList(Record, Attr); 4128} 4129 4130EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4131 EnumConstantDecl *LastEnumConst, 4132 SourceLocation IdLoc, 4133 IdentifierInfo *Id, 4134 ExprArg val) { 4135 Expr *Val = (Expr *)val.get(); 4136 4137 llvm::APSInt EnumVal(32); 4138 QualType EltTy; 4139 if (Val && !Val->isTypeDependent()) { 4140 // Make sure to promote the operand type to int. 4141 UsualUnaryConversions(Val); 4142 if (Val != val.get()) { 4143 val.release(); 4144 val = Val; 4145 } 4146 4147 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4148 SourceLocation ExpLoc; 4149 if (!Val->isValueDependent() && 4150 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4151 Val = 0; 4152 } else { 4153 EltTy = Val->getType(); 4154 } 4155 } 4156 4157 if (!Val) { 4158 if (LastEnumConst) { 4159 // Assign the last value + 1. 4160 EnumVal = LastEnumConst->getInitVal(); 4161 ++EnumVal; 4162 4163 // Check for overflow on increment. 4164 if (EnumVal < LastEnumConst->getInitVal()) 4165 Diag(IdLoc, diag::warn_enum_value_overflow); 4166 4167 EltTy = LastEnumConst->getType(); 4168 } else { 4169 // First value, set to zero. 4170 EltTy = Context.IntTy; 4171 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4172 } 4173 } 4174 4175 val.release(); 4176 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4177 Val, EnumVal); 4178} 4179 4180 4181Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4182 DeclPtrTy lastEnumConst, 4183 SourceLocation IdLoc, 4184 IdentifierInfo *Id, 4185 SourceLocation EqualLoc, ExprTy *val) { 4186 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4187 EnumConstantDecl *LastEnumConst = 4188 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4189 Expr *Val = static_cast<Expr*>(val); 4190 4191 // The scope passed in may not be a decl scope. Zip up the scope tree until 4192 // we find one that is. 4193 S = getNonFieldDeclScope(S); 4194 4195 // Verify that there isn't already something declared with this name in this 4196 // scope. 4197 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4198 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4199 // Maybe we will complain about the shadowed template parameter. 4200 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4201 // Just pretend that we didn't see the previous declaration. 4202 PrevDecl = 0; 4203 } 4204 4205 if (PrevDecl) { 4206 // When in C++, we may get a TagDecl with the same name; in this case the 4207 // enum constant will 'hide' the tag. 4208 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4209 "Received TagDecl when not in C++!"); 4210 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4211 if (isa<EnumConstantDecl>(PrevDecl)) 4212 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4213 else 4214 Diag(IdLoc, diag::err_redefinition) << Id; 4215 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4216 if (Val) Val->Destroy(Context); 4217 return DeclPtrTy(); 4218 } 4219 } 4220 4221 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4222 IdLoc, Id, Owned(Val)); 4223 4224 // Register this decl in the current scope stack. 4225 if (New) 4226 PushOnScopeChains(New, S); 4227 4228 return DeclPtrTy::make(New); 4229} 4230 4231void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 4232 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 4233 DeclPtrTy *Elements, unsigned NumElements) { 4234 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4235 QualType EnumType = Context.getTypeDeclType(Enum); 4236 4237 // TODO: If the result value doesn't fit in an int, it must be a long or long 4238 // long value. ISO C does not support this, but GCC does as an extension, 4239 // emit a warning. 4240 unsigned IntWidth = Context.Target.getIntWidth(); 4241 4242 // Verify that all the values are okay, compute the size of the values, and 4243 // reverse the list. 4244 unsigned NumNegativeBits = 0; 4245 unsigned NumPositiveBits = 0; 4246 4247 // Keep track of whether all elements have type int. 4248 bool AllElementsInt = true; 4249 4250 for (unsigned i = 0; i != NumElements; ++i) { 4251 EnumConstantDecl *ECD = 4252 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4253 if (!ECD) continue; // Already issued a diagnostic. 4254 4255 // If the enum value doesn't fit in an int, emit an extension warning. 4256 const llvm::APSInt &InitVal = ECD->getInitVal(); 4257 assert(InitVal.getBitWidth() >= IntWidth && 4258 "Should have promoted value to int"); 4259 if (InitVal.getBitWidth() > IntWidth) { 4260 llvm::APSInt V(InitVal); 4261 V.trunc(IntWidth); 4262 V.extend(InitVal.getBitWidth()); 4263 if (V != InitVal) 4264 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4265 << InitVal.toString(10); 4266 } 4267 4268 // Keep track of the size of positive and negative values. 4269 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4270 NumPositiveBits = std::max(NumPositiveBits, 4271 (unsigned)InitVal.getActiveBits()); 4272 else 4273 NumNegativeBits = std::max(NumNegativeBits, 4274 (unsigned)InitVal.getMinSignedBits()); 4275 4276 // Keep track of whether every enum element has type int (very commmon). 4277 if (AllElementsInt) 4278 AllElementsInt = ECD->getType() == Context.IntTy; 4279 } 4280 4281 // Figure out the type that should be used for this enum. 4282 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4283 QualType BestType; 4284 unsigned BestWidth; 4285 4286 if (NumNegativeBits) { 4287 // If there is a negative value, figure out the smallest integer type (of 4288 // int/long/longlong) that fits. 4289 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4290 BestType = Context.IntTy; 4291 BestWidth = IntWidth; 4292 } else { 4293 BestWidth = Context.Target.getLongWidth(); 4294 4295 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4296 BestType = Context.LongTy; 4297 else { 4298 BestWidth = Context.Target.getLongLongWidth(); 4299 4300 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4301 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4302 BestType = Context.LongLongTy; 4303 } 4304 } 4305 } else { 4306 // If there is no negative value, figure out which of uint, ulong, ulonglong 4307 // fits. 4308 if (NumPositiveBits <= IntWidth) { 4309 BestType = Context.UnsignedIntTy; 4310 BestWidth = IntWidth; 4311 } else if (NumPositiveBits <= 4312 (BestWidth = Context.Target.getLongWidth())) { 4313 BestType = Context.UnsignedLongTy; 4314 } else { 4315 BestWidth = Context.Target.getLongLongWidth(); 4316 assert(NumPositiveBits <= BestWidth && 4317 "How could an initializer get larger than ULL?"); 4318 BestType = Context.UnsignedLongLongTy; 4319 } 4320 } 4321 4322 // Loop over all of the enumerator constants, changing their types to match 4323 // the type of the enum if needed. 4324 for (unsigned i = 0; i != NumElements; ++i) { 4325 EnumConstantDecl *ECD = 4326 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4327 if (!ECD) continue; // Already issued a diagnostic. 4328 4329 // Standard C says the enumerators have int type, but we allow, as an 4330 // extension, the enumerators to be larger than int size. If each 4331 // enumerator value fits in an int, type it as an int, otherwise type it the 4332 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4333 // that X has type 'int', not 'unsigned'. 4334 if (ECD->getType() == Context.IntTy) { 4335 // Make sure the init value is signed. 4336 llvm::APSInt IV = ECD->getInitVal(); 4337 IV.setIsSigned(true); 4338 ECD->setInitVal(IV); 4339 4340 if (getLangOptions().CPlusPlus) 4341 // C++ [dcl.enum]p4: Following the closing brace of an 4342 // enum-specifier, each enumerator has the type of its 4343 // enumeration. 4344 ECD->setType(EnumType); 4345 continue; // Already int type. 4346 } 4347 4348 // Determine whether the value fits into an int. 4349 llvm::APSInt InitVal = ECD->getInitVal(); 4350 bool FitsInInt; 4351 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4352 FitsInInt = InitVal.getActiveBits() < IntWidth; 4353 else 4354 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4355 4356 // If it fits into an integer type, force it. Otherwise force it to match 4357 // the enum decl type. 4358 QualType NewTy; 4359 unsigned NewWidth; 4360 bool NewSign; 4361 if (FitsInInt) { 4362 NewTy = Context.IntTy; 4363 NewWidth = IntWidth; 4364 NewSign = true; 4365 } else if (ECD->getType() == BestType) { 4366 // Already the right type! 4367 if (getLangOptions().CPlusPlus) 4368 // C++ [dcl.enum]p4: Following the closing brace of an 4369 // enum-specifier, each enumerator has the type of its 4370 // enumeration. 4371 ECD->setType(EnumType); 4372 continue; 4373 } else { 4374 NewTy = BestType; 4375 NewWidth = BestWidth; 4376 NewSign = BestType->isSignedIntegerType(); 4377 } 4378 4379 // Adjust the APSInt value. 4380 InitVal.extOrTrunc(NewWidth); 4381 InitVal.setIsSigned(NewSign); 4382 ECD->setInitVal(InitVal); 4383 4384 // Adjust the Expr initializer and type. 4385 if (ECD->getInitExpr()) 4386 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4387 /*isLvalue=*/false)); 4388 if (getLangOptions().CPlusPlus) 4389 // C++ [dcl.enum]p4: Following the closing brace of an 4390 // enum-specifier, each enumerator has the type of its 4391 // enumeration. 4392 ECD->setType(EnumType); 4393 else 4394 ECD->setType(NewTy); 4395 } 4396 4397 Enum->completeDefinition(Context, BestType); 4398} 4399 4400Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4401 ExprArg expr) { 4402 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4403 4404 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4405 Loc, AsmString)); 4406} 4407