SemaDecl.cpp revision edf8844f2e68617892c6883fedd343efd987df68
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/AST/StmtCXX.h" 22#include "clang/Parse/DeclSpec.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Basic/SourceManager.h" 25// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 26#include "clang/Lex/Preprocessor.h" 27#include "clang/Lex/HeaderSearch.h" 28#include "llvm/ADT/SmallSet.h" 29#include "llvm/ADT/STLExtras.h" 30#include <algorithm> 31#include <functional> 32using namespace clang; 33 34/// getDeclName - Return a pretty name for the specified decl if possible, or 35/// an empty string if not. This is used for pretty crash reporting. 36std::string Sema::getDeclName(DeclPtrTy d) { 37 Decl *D = d.getAs<Decl>(); 38 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 39 return DN->getQualifiedNameAsString(); 40 return ""; 41} 42 43Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 44 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 45} 46 47/// \brief If the identifier refers to a type name within this scope, 48/// return the declaration of that type. 49/// 50/// This routine performs ordinary name lookup of the identifier II 51/// within the given scope, with optional C++ scope specifier SS, to 52/// determine whether the name refers to a type. If so, returns an 53/// opaque pointer (actually a QualType) corresponding to that 54/// type. Otherwise, returns NULL. 55/// 56/// If name lookup results in an ambiguity, this routine will complain 57/// and then return NULL. 58Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 59 Scope *S, const CXXScopeSpec *SS) { 60 // C++ [temp.res]p3: 61 // A qualified-id that refers to a type and in which the 62 // nested-name-specifier depends on a template-parameter (14.6.2) 63 // shall be prefixed by the keyword typename to indicate that the 64 // qualified-id denotes a type, forming an 65 // elaborated-type-specifier (7.1.5.3). 66 // 67 // We therefore do not perform any name lookup if the result would 68 // refer to a member of an unknown specialization. 69 if (SS && isUnknownSpecialization(*SS)) 70 return 0; 71 72 LookupResult Result 73 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 74 75 NamedDecl *IIDecl = 0; 76 switch (Result.getKind()) { 77 case LookupResult::NotFound: 78 case LookupResult::FoundOverloaded: 79 return 0; 80 81 case LookupResult::AmbiguousBaseSubobjectTypes: 82 case LookupResult::AmbiguousBaseSubobjects: 83 case LookupResult::AmbiguousReference: { 84 // Look to see if we have a type anywhere in the list of results. 85 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 86 Res != ResEnd; ++Res) { 87 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 88 if (!IIDecl || 89 (*Res)->getLocation().getRawEncoding() < 90 IIDecl->getLocation().getRawEncoding()) 91 IIDecl = *Res; 92 } 93 } 94 95 if (!IIDecl) { 96 // None of the entities we found is a type, so there is no way 97 // to even assume that the result is a type. In this case, don't 98 // complain about the ambiguity. The parser will either try to 99 // perform this lookup again (e.g., as an object name), which 100 // will produce the ambiguity, or will complain that it expected 101 // a type name. 102 Result.Destroy(); 103 return 0; 104 } 105 106 // We found a type within the ambiguous lookup; diagnose the 107 // ambiguity and then return that type. This might be the right 108 // answer, or it might not be, but it suppresses any attempt to 109 // perform the name lookup again. 110 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 111 break; 112 } 113 114 case LookupResult::Found: 115 IIDecl = Result.getAsDecl(); 116 break; 117 } 118 119 if (IIDecl) { 120 QualType T; 121 122 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 123 // Check whether we can use this type 124 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 125 126 if (getLangOptions().CPlusPlus) { 127 // C++ [temp.local]p2: 128 // Within the scope of a class template specialization or 129 // partial specialization, when the injected-class-name is 130 // not followed by a <, it is equivalent to the 131 // injected-class-name followed by the template-argument s 132 // of the class template specialization or partial 133 // specialization enclosed in <>. 134 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 135 if (RD->isInjectedClassName()) 136 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 137 T = Template->getInjectedClassNameType(Context); 138 } 139 140 if (T.isNull()) 141 T = Context.getTypeDeclType(TD); 142 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 143 // Check whether we can use this interface. 144 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 145 146 T = Context.getObjCInterfaceType(IDecl); 147 } else 148 return 0; 149 150 if (SS) 151 T = getQualifiedNameType(*SS, T); 152 153 return T.getAsOpaquePtr(); 154 } 155 156 return 0; 157} 158 159/// isTagName() - This method is called *for error recovery purposes only* 160/// to determine if the specified name is a valid tag name ("struct foo"). If 161/// so, this returns the TST for the tag corresponding to it (TST_enum, 162/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 163/// where the user forgot to specify the tag. 164DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 165 // Do a tag name lookup in this scope. 166 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 167 if (R.getKind() == LookupResult::Found) 168 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 169 switch (TD->getTagKind()) { 170 case TagDecl::TK_struct: return DeclSpec::TST_struct; 171 case TagDecl::TK_union: return DeclSpec::TST_union; 172 case TagDecl::TK_class: return DeclSpec::TST_class; 173 case TagDecl::TK_enum: return DeclSpec::TST_enum; 174 } 175 } 176 177 return DeclSpec::TST_unspecified; 178} 179 180 181 182DeclContext *Sema::getContainingDC(DeclContext *DC) { 183 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 184 // A C++ out-of-line method will return to the file declaration context. 185 if (MD->isOutOfLineDefinition()) 186 return MD->getLexicalDeclContext(); 187 188 // A C++ inline method is parsed *after* the topmost class it was declared 189 // in is fully parsed (it's "complete"). 190 // The parsing of a C++ inline method happens at the declaration context of 191 // the topmost (non-nested) class it is lexically declared in. 192 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 193 DC = MD->getParent(); 194 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 195 DC = RD; 196 197 // Return the declaration context of the topmost class the inline method is 198 // declared in. 199 return DC; 200 } 201 202 if (isa<ObjCMethodDecl>(DC)) 203 return Context.getTranslationUnitDecl(); 204 205 return DC->getLexicalParent(); 206} 207 208void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 209 assert(getContainingDC(DC) == CurContext && 210 "The next DeclContext should be lexically contained in the current one."); 211 CurContext = DC; 212 S->setEntity(DC); 213} 214 215void Sema::PopDeclContext() { 216 assert(CurContext && "DeclContext imbalance!"); 217 218 CurContext = getContainingDC(CurContext); 219} 220 221/// \brief Determine whether we allow overloading of the function 222/// PrevDecl with another declaration. 223/// 224/// This routine determines whether overloading is possible, not 225/// whether some new function is actually an overload. It will return 226/// true in C++ (where we can always provide overloads) or, as an 227/// extension, in C when the previous function is already an 228/// overloaded function declaration or has the "overloadable" 229/// attribute. 230static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 231 if (Context.getLangOptions().CPlusPlus) 232 return true; 233 234 if (isa<OverloadedFunctionDecl>(PrevDecl)) 235 return true; 236 237 return PrevDecl->getAttr<OverloadableAttr>() != 0; 238} 239 240/// Add this decl to the scope shadowed decl chains. 241void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 242 // Move up the scope chain until we find the nearest enclosing 243 // non-transparent context. The declaration will be introduced into this 244 // scope. 245 while (S->getEntity() && 246 ((DeclContext *)S->getEntity())->isTransparentContext()) 247 S = S->getParent(); 248 249 S->AddDecl(DeclPtrTy::make(D)); 250 251 // Add scoped declarations into their context, so that they can be 252 // found later. Declarations without a context won't be inserted 253 // into any context. 254 CurContext->addDecl(Context, D); 255 256 // C++ [basic.scope]p4: 257 // -- exactly one declaration shall declare a class name or 258 // enumeration name that is not a typedef name and the other 259 // declarations shall all refer to the same object or 260 // enumerator, or all refer to functions and function templates; 261 // in this case the class name or enumeration name is hidden. 262 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 263 // We are pushing the name of a tag (enum or class). 264 if (CurContext->getLookupContext() 265 == TD->getDeclContext()->getLookupContext()) { 266 // We're pushing the tag into the current context, which might 267 // require some reshuffling in the identifier resolver. 268 IdentifierResolver::iterator 269 I = IdResolver.begin(TD->getDeclName()), 270 IEnd = IdResolver.end(); 271 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 272 NamedDecl *PrevDecl = *I; 273 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 274 PrevDecl = *I, ++I) { 275 if (TD->declarationReplaces(*I)) { 276 // This is a redeclaration. Remove it from the chain and 277 // break out, so that we'll add in the shadowed 278 // declaration. 279 S->RemoveDecl(DeclPtrTy::make(*I)); 280 if (PrevDecl == *I) { 281 IdResolver.RemoveDecl(*I); 282 IdResolver.AddDecl(TD); 283 return; 284 } else { 285 IdResolver.RemoveDecl(*I); 286 break; 287 } 288 } 289 } 290 291 // There is already a declaration with the same name in the same 292 // scope, which is not a tag declaration. It must be found 293 // before we find the new declaration, so insert the new 294 // declaration at the end of the chain. 295 IdResolver.AddShadowedDecl(TD, PrevDecl); 296 297 return; 298 } 299 } 300 } else if (isa<FunctionDecl>(D) && 301 AllowOverloadingOfFunction(D, Context)) { 302 // We are pushing the name of a function, which might be an 303 // overloaded name. 304 FunctionDecl *FD = cast<FunctionDecl>(D); 305 IdentifierResolver::iterator Redecl 306 = std::find_if(IdResolver.begin(FD->getDeclName()), 307 IdResolver.end(), 308 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 309 FD)); 310 if (Redecl != IdResolver.end() && 311 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 312 // There is already a declaration of a function on our 313 // IdResolver chain. Replace it with this declaration. 314 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 315 IdResolver.RemoveDecl(*Redecl); 316 } 317 } else if (isa<ObjCInterfaceDecl>(D)) { 318 // We're pushing an Objective-C interface into the current 319 // context. If there is already an alias declaration, remove it first. 320 for (IdentifierResolver::iterator 321 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 322 I != IEnd; ++I) { 323 if (isa<ObjCCompatibleAliasDecl>(*I)) { 324 S->RemoveDecl(DeclPtrTy::make(*I)); 325 IdResolver.RemoveDecl(*I); 326 break; 327 } 328 } 329 } 330 331 IdResolver.AddDecl(D); 332} 333 334void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 335 if (S->decl_empty()) return; 336 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 337 "Scope shouldn't contain decls!"); 338 339 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 340 I != E; ++I) { 341 Decl *TmpD = (*I).getAs<Decl>(); 342 assert(TmpD && "This decl didn't get pushed??"); 343 344 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 345 NamedDecl *D = cast<NamedDecl>(TmpD); 346 347 if (!D->getDeclName()) continue; 348 349 // Remove this name from our lexical scope. 350 IdResolver.RemoveDecl(D); 351 } 352} 353 354/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 355/// return 0 if one not found. 356ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 357 // The third "scope" argument is 0 since we aren't enabling lazy built-in 358 // creation from this context. 359 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 360 361 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 362} 363 364/// getNonFieldDeclScope - Retrieves the innermost scope, starting 365/// from S, where a non-field would be declared. This routine copes 366/// with the difference between C and C++ scoping rules in structs and 367/// unions. For example, the following code is well-formed in C but 368/// ill-formed in C++: 369/// @code 370/// struct S6 { 371/// enum { BAR } e; 372/// }; 373/// 374/// void test_S6() { 375/// struct S6 a; 376/// a.e = BAR; 377/// } 378/// @endcode 379/// For the declaration of BAR, this routine will return a different 380/// scope. The scope S will be the scope of the unnamed enumeration 381/// within S6. In C++, this routine will return the scope associated 382/// with S6, because the enumeration's scope is a transparent 383/// context but structures can contain non-field names. In C, this 384/// routine will return the translation unit scope, since the 385/// enumeration's scope is a transparent context and structures cannot 386/// contain non-field names. 387Scope *Sema::getNonFieldDeclScope(Scope *S) { 388 while (((S->getFlags() & Scope::DeclScope) == 0) || 389 (S->getEntity() && 390 ((DeclContext *)S->getEntity())->isTransparentContext()) || 391 (S->isClassScope() && !getLangOptions().CPlusPlus)) 392 S = S->getParent(); 393 return S; 394} 395 396void Sema::InitBuiltinVaListType() { 397 if (!Context.getBuiltinVaListType().isNull()) 398 return; 399 400 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 401 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 402 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 403 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 404} 405 406/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 407/// file scope. lazily create a decl for it. ForRedeclaration is true 408/// if we're creating this built-in in anticipation of redeclaring the 409/// built-in. 410NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 411 Scope *S, bool ForRedeclaration, 412 SourceLocation Loc) { 413 Builtin::ID BID = (Builtin::ID)bid; 414 415 if (Context.BuiltinInfo.hasVAListUse(BID)) 416 InitBuiltinVaListType(); 417 418 Builtin::Context::GetBuiltinTypeError Error; 419 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 420 switch (Error) { 421 case Builtin::Context::GE_None: 422 // Okay 423 break; 424 425 case Builtin::Context::GE_Missing_FILE: 426 if (ForRedeclaration) 427 Diag(Loc, diag::err_implicit_decl_requires_stdio) 428 << Context.BuiltinInfo.GetName(BID); 429 return 0; 430 } 431 432 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 433 Diag(Loc, diag::ext_implicit_lib_function_decl) 434 << Context.BuiltinInfo.GetName(BID) 435 << R; 436 if (Context.BuiltinInfo.getHeaderName(BID) && 437 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 438 != Diagnostic::Ignored) 439 Diag(Loc, diag::note_please_include_header) 440 << Context.BuiltinInfo.getHeaderName(BID) 441 << Context.BuiltinInfo.GetName(BID); 442 } 443 444 FunctionDecl *New = FunctionDecl::Create(Context, 445 Context.getTranslationUnitDecl(), 446 Loc, II, R, 447 FunctionDecl::Extern, false, 448 /*hasPrototype=*/true); 449 New->setImplicit(); 450 451 // Create Decl objects for each parameter, adding them to the 452 // FunctionDecl. 453 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 454 llvm::SmallVector<ParmVarDecl*, 16> Params; 455 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 456 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 457 FT->getArgType(i), VarDecl::None, 0)); 458 New->setParams(Context, &Params[0], Params.size()); 459 } 460 461 AddKnownFunctionAttributes(New); 462 463 // TUScope is the translation-unit scope to insert this function into. 464 // FIXME: This is hideous. We need to teach PushOnScopeChains to 465 // relate Scopes to DeclContexts, and probably eliminate CurContext 466 // entirely, but we're not there yet. 467 DeclContext *SavedContext = CurContext; 468 CurContext = Context.getTranslationUnitDecl(); 469 PushOnScopeChains(New, TUScope); 470 CurContext = SavedContext; 471 return New; 472} 473 474/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 475/// everything from the standard library is defined. 476NamespaceDecl *Sema::GetStdNamespace() { 477 if (!StdNamespace) { 478 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 479 DeclContext *Global = Context.getTranslationUnitDecl(); 480 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 481 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 482 } 483 return StdNamespace; 484} 485 486/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 487/// same name and scope as a previous declaration 'Old'. Figure out 488/// how to resolve this situation, merging decls or emitting 489/// diagnostics as appropriate. If there was an error, set New to be invalid. 490/// 491void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 492 // If either decl is known invalid already, set the new one to be invalid and 493 // don't bother doing any merging checks. 494 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 495 return New->setInvalidDecl(); 496 497 bool objc_types = false; 498 499 // Allow multiple definitions for ObjC built-in typedefs. 500 // FIXME: Verify the underlying types are equivalent! 501 if (getLangOptions().ObjC1) { 502 const IdentifierInfo *TypeID = New->getIdentifier(); 503 switch (TypeID->getLength()) { 504 default: break; 505 case 2: 506 if (!TypeID->isStr("id")) 507 break; 508 Context.setObjCIdType(Context.getTypeDeclType(New)); 509 objc_types = true; 510 break; 511 case 5: 512 if (!TypeID->isStr("Class")) 513 break; 514 Context.setObjCClassType(Context.getTypeDeclType(New)); 515 return; 516 case 3: 517 if (!TypeID->isStr("SEL")) 518 break; 519 Context.setObjCSelType(Context.getTypeDeclType(New)); 520 return; 521 case 8: 522 if (!TypeID->isStr("Protocol")) 523 break; 524 Context.setObjCProtoType(New->getUnderlyingType()); 525 return; 526 } 527 // Fall through - the typedef name was not a builtin type. 528 } 529 // Verify the old decl was also a type. 530 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 531 if (!Old) { 532 Diag(New->getLocation(), diag::err_redefinition_different_kind) 533 << New->getDeclName(); 534 if (OldD->getLocation().isValid()) 535 Diag(OldD->getLocation(), diag::note_previous_definition); 536 return New->setInvalidDecl(); 537 } 538 539 // Determine the "old" type we'll use for checking and diagnostics. 540 QualType OldType; 541 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 542 OldType = OldTypedef->getUnderlyingType(); 543 else 544 OldType = Context.getTypeDeclType(Old); 545 546 // If the typedef types are not identical, reject them in all languages and 547 // with any extensions enabled. 548 549 if (OldType != New->getUnderlyingType() && 550 Context.getCanonicalType(OldType) != 551 Context.getCanonicalType(New->getUnderlyingType())) { 552 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 553 << New->getUnderlyingType() << OldType; 554 if (Old->getLocation().isValid()) 555 Diag(Old->getLocation(), diag::note_previous_definition); 556 return New->setInvalidDecl(); 557 } 558 559 if (objc_types || getLangOptions().Microsoft) 560 return; 561 562 // C++ [dcl.typedef]p2: 563 // In a given non-class scope, a typedef specifier can be used to 564 // redefine the name of any type declared in that scope to refer 565 // to the type to which it already refers. 566 if (getLangOptions().CPlusPlus) { 567 if (!isa<CXXRecordDecl>(CurContext)) 568 return; 569 Diag(New->getLocation(), diag::err_redefinition) 570 << New->getDeclName(); 571 Diag(Old->getLocation(), diag::note_previous_definition); 572 return New->setInvalidDecl(); 573 } 574 575 // If we have a redefinition of a typedef in C, emit a warning. This warning 576 // is normally mapped to an error, but can be controlled with 577 // -Wtypedef-redefinition. If either the original was in a system header, 578 // don't emit this for compatibility with GCC. 579 if (PP.getDiagnostics().getSuppressSystemWarnings() && 580 Context.getSourceManager().isInSystemHeader(Old->getLocation())) 581 return; 582 583 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 584 << New->getDeclName(); 585 Diag(Old->getLocation(), diag::note_previous_definition); 586 return; 587} 588 589/// DeclhasAttr - returns true if decl Declaration already has the target 590/// attribute. 591static bool DeclHasAttr(const Decl *decl, const Attr *target) { 592 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 593 if (attr->getKind() == target->getKind()) 594 return true; 595 596 return false; 597} 598 599/// MergeAttributes - append attributes from the Old decl to the New one. 600static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 601 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 602 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 603 Attr *NewAttr = attr->clone(C); 604 NewAttr->setInherited(true); 605 New->addAttr(NewAttr); 606 } 607 } 608} 609 610/// Used in MergeFunctionDecl to keep track of function parameters in 611/// C. 612struct GNUCompatibleParamWarning { 613 ParmVarDecl *OldParm; 614 ParmVarDecl *NewParm; 615 QualType PromotedType; 616}; 617 618/// MergeFunctionDecl - We just parsed a function 'New' from 619/// declarator D which has the same name and scope as a previous 620/// declaration 'Old'. Figure out how to resolve this situation, 621/// merging decls or emitting diagnostics as appropriate. 622/// 623/// In C++, New and Old must be declarations that are not 624/// overloaded. Use IsOverload to determine whether New and Old are 625/// overloaded, and to select the Old declaration that New should be 626/// merged with. 627/// 628/// Returns true if there was an error, false otherwise. 629bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 630 assert(!isa<OverloadedFunctionDecl>(OldD) && 631 "Cannot merge with an overloaded function declaration"); 632 633 // Verify the old decl was also a function. 634 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 635 if (!Old) { 636 Diag(New->getLocation(), diag::err_redefinition_different_kind) 637 << New->getDeclName(); 638 Diag(OldD->getLocation(), diag::note_previous_definition); 639 return true; 640 } 641 642 // Determine whether the previous declaration was a definition, 643 // implicit declaration, or a declaration. 644 diag::kind PrevDiag; 645 if (Old->isThisDeclarationADefinition()) 646 PrevDiag = diag::note_previous_definition; 647 else if (Old->isImplicit()) 648 PrevDiag = diag::note_previous_implicit_declaration; 649 else 650 PrevDiag = diag::note_previous_declaration; 651 652 QualType OldQType = Context.getCanonicalType(Old->getType()); 653 QualType NewQType = Context.getCanonicalType(New->getType()); 654 655 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 656 New->getStorageClass() == FunctionDecl::Static && 657 Old->getStorageClass() != FunctionDecl::Static) { 658 Diag(New->getLocation(), diag::err_static_non_static) 659 << New; 660 Diag(Old->getLocation(), PrevDiag); 661 return true; 662 } 663 664 if (getLangOptions().CPlusPlus) { 665 // (C++98 13.1p2): 666 // Certain function declarations cannot be overloaded: 667 // -- Function declarations that differ only in the return type 668 // cannot be overloaded. 669 QualType OldReturnType 670 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 671 QualType NewReturnType 672 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 673 if (OldReturnType != NewReturnType) { 674 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 675 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 676 return true; 677 } 678 679 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 680 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 681 if (OldMethod && NewMethod && 682 OldMethod->getLexicalDeclContext() == 683 NewMethod->getLexicalDeclContext()) { 684 // -- Member function declarations with the same name and the 685 // same parameter types cannot be overloaded if any of them 686 // is a static member function declaration. 687 if (OldMethod->isStatic() || NewMethod->isStatic()) { 688 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 689 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 690 return true; 691 } 692 693 // C++ [class.mem]p1: 694 // [...] A member shall not be declared twice in the 695 // member-specification, except that a nested class or member 696 // class template can be declared and then later defined. 697 unsigned NewDiag; 698 if (isa<CXXConstructorDecl>(OldMethod)) 699 NewDiag = diag::err_constructor_redeclared; 700 else if (isa<CXXDestructorDecl>(NewMethod)) 701 NewDiag = diag::err_destructor_redeclared; 702 else if (isa<CXXConversionDecl>(NewMethod)) 703 NewDiag = diag::err_conv_function_redeclared; 704 else 705 NewDiag = diag::err_member_redeclared; 706 707 Diag(New->getLocation(), NewDiag); 708 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 709 } 710 711 // (C++98 8.3.5p3): 712 // All declarations for a function shall agree exactly in both the 713 // return type and the parameter-type-list. 714 if (OldQType == NewQType) 715 return MergeCompatibleFunctionDecls(New, Old); 716 717 // Fall through for conflicting redeclarations and redefinitions. 718 } 719 720 // C: Function types need to be compatible, not identical. This handles 721 // duplicate function decls like "void f(int); void f(enum X);" properly. 722 if (!getLangOptions().CPlusPlus && 723 Context.typesAreCompatible(OldQType, NewQType)) { 724 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 725 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 726 const FunctionProtoType *OldProto = 0; 727 if (isa<FunctionNoProtoType>(NewFuncType) && 728 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 729 // The old declaration provided a function prototype, but the 730 // new declaration does not. Merge in the prototype. 731 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 732 OldProto->arg_type_end()); 733 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 734 &ParamTypes[0], ParamTypes.size(), 735 OldProto->isVariadic(), 736 OldProto->getTypeQuals()); 737 New->setType(NewQType); 738 New->setInheritedPrototype(); 739 740 // Synthesize a parameter for each argument type. 741 llvm::SmallVector<ParmVarDecl*, 16> Params; 742 for (FunctionProtoType::arg_type_iterator 743 ParamType = OldProto->arg_type_begin(), 744 ParamEnd = OldProto->arg_type_end(); 745 ParamType != ParamEnd; ++ParamType) { 746 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 747 SourceLocation(), 0, 748 *ParamType, VarDecl::None, 749 0); 750 Param->setImplicit(); 751 Params.push_back(Param); 752 } 753 754 New->setParams(Context, &Params[0], Params.size()); 755 } 756 757 return MergeCompatibleFunctionDecls(New, Old); 758 } 759 760 // GNU C permits a K&R definition to follow a prototype declaration 761 // if the declared types of the parameters in the K&R definition 762 // match the types in the prototype declaration, even when the 763 // promoted types of the parameters from the K&R definition differ 764 // from the types in the prototype. GCC then keeps the types from 765 // the prototype. 766 if (!getLangOptions().CPlusPlus && 767 Old->hasPrototype() && !New->hasPrototype() && 768 New->getType()->getAsFunctionProtoType() && 769 Old->getNumParams() == New->getNumParams()) { 770 llvm::SmallVector<QualType, 16> ArgTypes; 771 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 772 const FunctionProtoType *OldProto 773 = Old->getType()->getAsFunctionProtoType(); 774 const FunctionProtoType *NewProto 775 = New->getType()->getAsFunctionProtoType(); 776 777 // Determine whether this is the GNU C extension. 778 bool GNUCompatible = 779 Context.typesAreCompatible(OldProto->getResultType(), 780 NewProto->getResultType()) && 781 (OldProto->isVariadic() == NewProto->isVariadic()); 782 for (unsigned Idx = 0, End = Old->getNumParams(); 783 GNUCompatible && Idx != End; ++Idx) { 784 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 785 ParmVarDecl *NewParm = New->getParamDecl(Idx); 786 if (Context.typesAreCompatible(OldParm->getType(), 787 NewProto->getArgType(Idx))) { 788 ArgTypes.push_back(NewParm->getType()); 789 } else if (Context.typesAreCompatible(OldParm->getType(), 790 NewParm->getType())) { 791 GNUCompatibleParamWarning Warn 792 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 793 Warnings.push_back(Warn); 794 ArgTypes.push_back(NewParm->getType()); 795 } else 796 GNUCompatible = false; 797 } 798 799 if (GNUCompatible) { 800 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 801 Diag(Warnings[Warn].NewParm->getLocation(), 802 diag::ext_param_promoted_not_compatible_with_prototype) 803 << Warnings[Warn].PromotedType 804 << Warnings[Warn].OldParm->getType(); 805 Diag(Warnings[Warn].OldParm->getLocation(), 806 diag::note_previous_declaration); 807 } 808 809 New->setType(Context.getFunctionType(NewProto->getResultType(), 810 &ArgTypes[0], ArgTypes.size(), 811 NewProto->isVariadic(), 812 NewProto->getTypeQuals())); 813 return MergeCompatibleFunctionDecls(New, Old); 814 } 815 816 // Fall through to diagnose conflicting types. 817 } 818 819 // A function that has already been declared has been redeclared or defined 820 // with a different type- show appropriate diagnostic 821 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 822 // The user has declared a builtin function with an incompatible 823 // signature. 824 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 825 // The function the user is redeclaring is a library-defined 826 // function like 'malloc' or 'printf'. Warn about the 827 // redeclaration, then pretend that we don't know about this 828 // library built-in. 829 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 830 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 831 << Old << Old->getType(); 832 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 833 Old->setInvalidDecl(); 834 return false; 835 } 836 837 PrevDiag = diag::note_previous_builtin_declaration; 838 } 839 840 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 841 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 842 return true; 843} 844 845/// \brief Completes the merge of two function declarations that are 846/// known to be compatible. 847/// 848/// This routine handles the merging of attributes and other 849/// properties of function declarations form the old declaration to 850/// the new declaration, once we know that New is in fact a 851/// redeclaration of Old. 852/// 853/// \returns false 854bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 855 // Merge the attributes 856 MergeAttributes(New, Old, Context); 857 858 // Merge the storage class. 859 if (Old->getStorageClass() != FunctionDecl::Extern) 860 New->setStorageClass(Old->getStorageClass()); 861 862 // Merge "inline" 863 if (Old->isInline()) 864 New->setInline(true); 865 866 // If this function declaration by itself qualifies as a C99 inline 867 // definition (C99 6.7.4p6), but the previous definition did not, 868 // then the function is not a C99 inline definition. 869 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 870 New->setC99InlineDefinition(false); 871 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 872 // Mark all preceding definitions as not being C99 inline definitions. 873 for (const FunctionDecl *Prev = Old; Prev; 874 Prev = Prev->getPreviousDeclaration()) 875 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 876 } 877 878 // Merge "pure" flag. 879 if (Old->isPure()) 880 New->setPure(); 881 882 // Merge the "deleted" flag. 883 if (Old->isDeleted()) 884 New->setDeleted(); 885 886 if (getLangOptions().CPlusPlus) 887 return MergeCXXFunctionDecl(New, Old); 888 889 return false; 890} 891 892/// MergeVarDecl - We just parsed a variable 'New' which has the same name 893/// and scope as a previous declaration 'Old'. Figure out how to resolve this 894/// situation, merging decls or emitting diagnostics as appropriate. 895/// 896/// Tentative definition rules (C99 6.9.2p2) are checked by 897/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 898/// definitions here, since the initializer hasn't been attached. 899/// 900void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 901 // If either decl is invalid, make sure the new one is marked invalid and 902 // don't do any other checking. 903 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 904 return New->setInvalidDecl(); 905 906 // Verify the old decl was also a variable. 907 VarDecl *Old = dyn_cast<VarDecl>(OldD); 908 if (!Old) { 909 Diag(New->getLocation(), diag::err_redefinition_different_kind) 910 << New->getDeclName(); 911 Diag(OldD->getLocation(), diag::note_previous_definition); 912 return New->setInvalidDecl(); 913 } 914 915 MergeAttributes(New, Old, Context); 916 917 // Merge the types 918 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 919 if (MergedT.isNull()) { 920 Diag(New->getLocation(), diag::err_redefinition_different_type) 921 << New->getDeclName(); 922 Diag(Old->getLocation(), diag::note_previous_definition); 923 return New->setInvalidDecl(); 924 } 925 New->setType(MergedT); 926 927 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 928 if (New->getStorageClass() == VarDecl::Static && 929 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 930 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 931 Diag(Old->getLocation(), diag::note_previous_definition); 932 return New->setInvalidDecl(); 933 } 934 // C99 6.2.2p4: 935 // For an identifier declared with the storage-class specifier 936 // extern in a scope in which a prior declaration of that 937 // identifier is visible,23) if the prior declaration specifies 938 // internal or external linkage, the linkage of the identifier at 939 // the later declaration is the same as the linkage specified at 940 // the prior declaration. If no prior declaration is visible, or 941 // if the prior declaration specifies no linkage, then the 942 // identifier has external linkage. 943 if (New->hasExternalStorage() && Old->hasLinkage()) 944 /* Okay */; 945 else if (New->getStorageClass() != VarDecl::Static && 946 Old->getStorageClass() == VarDecl::Static) { 947 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 948 Diag(Old->getLocation(), diag::note_previous_definition); 949 return New->setInvalidDecl(); 950 } 951 952 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 953 954 // FIXME: The test for external storage here seems wrong? We still 955 // need to check for mismatches. 956 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 957 // Don't complain about out-of-line definitions of static members. 958 !(Old->getLexicalDeclContext()->isRecord() && 959 !New->getLexicalDeclContext()->isRecord())) { 960 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 961 Diag(Old->getLocation(), diag::note_previous_definition); 962 return New->setInvalidDecl(); 963 } 964 965 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 966 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 967 Diag(Old->getLocation(), diag::note_previous_definition); 968 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 969 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 970 Diag(Old->getLocation(), diag::note_previous_definition); 971 } 972 973 // Keep a chain of previous declarations. 974 New->setPreviousDeclaration(Old); 975} 976 977/// CheckParmsForFunctionDef - Check that the parameters of the given 978/// function are appropriate for the definition of a function. This 979/// takes care of any checks that cannot be performed on the 980/// declaration itself, e.g., that the types of each of the function 981/// parameters are complete. 982bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 983 bool HasInvalidParm = false; 984 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 985 ParmVarDecl *Param = FD->getParamDecl(p); 986 987 // C99 6.7.5.3p4: the parameters in a parameter type list in a 988 // function declarator that is part of a function definition of 989 // that function shall not have incomplete type. 990 // 991 // This is also C++ [dcl.fct]p6. 992 if (!Param->isInvalidDecl() && 993 RequireCompleteType(Param->getLocation(), Param->getType(), 994 diag::err_typecheck_decl_incomplete_type)) { 995 Param->setInvalidDecl(); 996 HasInvalidParm = true; 997 } 998 999 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1000 // declaration of each parameter shall include an identifier. 1001 if (Param->getIdentifier() == 0 && 1002 !Param->isImplicit() && 1003 !getLangOptions().CPlusPlus) 1004 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1005 } 1006 1007 return HasInvalidParm; 1008} 1009 1010/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1011/// no declarator (e.g. "struct foo;") is parsed. 1012Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1013 // FIXME: Error on auto/register at file scope 1014 // FIXME: Error on inline/virtual/explicit 1015 // FIXME: Error on invalid restrict 1016 // FIXME: Warn on useless __thread 1017 // FIXME: Warn on useless const/volatile 1018 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1019 // FIXME: Warn on useless attributes 1020 1021 TagDecl *Tag = 0; 1022 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1023 DS.getTypeSpecType() == DeclSpec::TST_struct || 1024 DS.getTypeSpecType() == DeclSpec::TST_union || 1025 DS.getTypeSpecType() == DeclSpec::TST_enum) 1026 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1027 1028 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1029 if (!Record->getDeclName() && Record->isDefinition() && 1030 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1031 if (getLangOptions().CPlusPlus || 1032 Record->getDeclContext()->isRecord()) 1033 return BuildAnonymousStructOrUnion(S, DS, Record); 1034 1035 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1036 << DS.getSourceRange(); 1037 } 1038 1039 // Microsoft allows unnamed struct/union fields. Don't complain 1040 // about them. 1041 // FIXME: Should we support Microsoft's extensions in this area? 1042 if (Record->getDeclName() && getLangOptions().Microsoft) 1043 return DeclPtrTy::make(Tag); 1044 } 1045 1046 if (!DS.isMissingDeclaratorOk() && 1047 DS.getTypeSpecType() != DeclSpec::TST_error) { 1048 // Warn about typedefs of enums without names, since this is an 1049 // extension in both Microsoft an GNU. 1050 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1051 Tag && isa<EnumDecl>(Tag)) { 1052 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1053 << DS.getSourceRange(); 1054 return DeclPtrTy::make(Tag); 1055 } 1056 1057 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1058 << DS.getSourceRange(); 1059 return DeclPtrTy(); 1060 } 1061 1062 return DeclPtrTy::make(Tag); 1063} 1064 1065/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1066/// anonymous struct or union AnonRecord into the owning context Owner 1067/// and scope S. This routine will be invoked just after we realize 1068/// that an unnamed union or struct is actually an anonymous union or 1069/// struct, e.g., 1070/// 1071/// @code 1072/// union { 1073/// int i; 1074/// float f; 1075/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1076/// // f into the surrounding scope.x 1077/// @endcode 1078/// 1079/// This routine is recursive, injecting the names of nested anonymous 1080/// structs/unions into the owning context and scope as well. 1081bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1082 RecordDecl *AnonRecord) { 1083 bool Invalid = false; 1084 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1085 FEnd = AnonRecord->field_end(Context); 1086 F != FEnd; ++F) { 1087 if ((*F)->getDeclName()) { 1088 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1089 LookupOrdinaryName, true); 1090 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1091 // C++ [class.union]p2: 1092 // The names of the members of an anonymous union shall be 1093 // distinct from the names of any other entity in the 1094 // scope in which the anonymous union is declared. 1095 unsigned diagKind 1096 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1097 : diag::err_anonymous_struct_member_redecl; 1098 Diag((*F)->getLocation(), diagKind) 1099 << (*F)->getDeclName(); 1100 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1101 Invalid = true; 1102 } else { 1103 // C++ [class.union]p2: 1104 // For the purpose of name lookup, after the anonymous union 1105 // definition, the members of the anonymous union are 1106 // considered to have been defined in the scope in which the 1107 // anonymous union is declared. 1108 Owner->makeDeclVisibleInContext(Context, *F); 1109 S->AddDecl(DeclPtrTy::make(*F)); 1110 IdResolver.AddDecl(*F); 1111 } 1112 } else if (const RecordType *InnerRecordType 1113 = (*F)->getType()->getAsRecordType()) { 1114 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1115 if (InnerRecord->isAnonymousStructOrUnion()) 1116 Invalid = Invalid || 1117 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1118 } 1119 } 1120 1121 return Invalid; 1122} 1123 1124/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1125/// anonymous structure or union. Anonymous unions are a C++ feature 1126/// (C++ [class.union]) and a GNU C extension; anonymous structures 1127/// are a GNU C and GNU C++ extension. 1128Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1129 RecordDecl *Record) { 1130 DeclContext *Owner = Record->getDeclContext(); 1131 1132 // Diagnose whether this anonymous struct/union is an extension. 1133 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1134 Diag(Record->getLocation(), diag::ext_anonymous_union); 1135 else if (!Record->isUnion()) 1136 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1137 1138 // C and C++ require different kinds of checks for anonymous 1139 // structs/unions. 1140 bool Invalid = false; 1141 if (getLangOptions().CPlusPlus) { 1142 const char* PrevSpec = 0; 1143 // C++ [class.union]p3: 1144 // Anonymous unions declared in a named namespace or in the 1145 // global namespace shall be declared static. 1146 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1147 (isa<TranslationUnitDecl>(Owner) || 1148 (isa<NamespaceDecl>(Owner) && 1149 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1150 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1151 Invalid = true; 1152 1153 // Recover by adding 'static'. 1154 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1155 } 1156 // C++ [class.union]p3: 1157 // A storage class is not allowed in a declaration of an 1158 // anonymous union in a class scope. 1159 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1160 isa<RecordDecl>(Owner)) { 1161 Diag(DS.getStorageClassSpecLoc(), 1162 diag::err_anonymous_union_with_storage_spec); 1163 Invalid = true; 1164 1165 // Recover by removing the storage specifier. 1166 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1167 PrevSpec); 1168 } 1169 1170 // C++ [class.union]p2: 1171 // The member-specification of an anonymous union shall only 1172 // define non-static data members. [Note: nested types and 1173 // functions cannot be declared within an anonymous union. ] 1174 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1175 MemEnd = Record->decls_end(Context); 1176 Mem != MemEnd; ++Mem) { 1177 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1178 // C++ [class.union]p3: 1179 // An anonymous union shall not have private or protected 1180 // members (clause 11). 1181 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1182 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1183 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1184 Invalid = true; 1185 } 1186 } else if ((*Mem)->isImplicit()) { 1187 // Any implicit members are fine. 1188 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1189 // This is a type that showed up in an 1190 // elaborated-type-specifier inside the anonymous struct or 1191 // union, but which actually declares a type outside of the 1192 // anonymous struct or union. It's okay. 1193 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1194 if (!MemRecord->isAnonymousStructOrUnion() && 1195 MemRecord->getDeclName()) { 1196 // This is a nested type declaration. 1197 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1198 << (int)Record->isUnion(); 1199 Invalid = true; 1200 } 1201 } else { 1202 // We have something that isn't a non-static data 1203 // member. Complain about it. 1204 unsigned DK = diag::err_anonymous_record_bad_member; 1205 if (isa<TypeDecl>(*Mem)) 1206 DK = diag::err_anonymous_record_with_type; 1207 else if (isa<FunctionDecl>(*Mem)) 1208 DK = diag::err_anonymous_record_with_function; 1209 else if (isa<VarDecl>(*Mem)) 1210 DK = diag::err_anonymous_record_with_static; 1211 Diag((*Mem)->getLocation(), DK) 1212 << (int)Record->isUnion(); 1213 Invalid = true; 1214 } 1215 } 1216 } 1217 1218 if (!Record->isUnion() && !Owner->isRecord()) { 1219 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1220 << (int)getLangOptions().CPlusPlus; 1221 Invalid = true; 1222 } 1223 1224 // Create a declaration for this anonymous struct/union. 1225 NamedDecl *Anon = 0; 1226 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1227 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1228 /*IdentifierInfo=*/0, 1229 Context.getTypeDeclType(Record), 1230 /*BitWidth=*/0, /*Mutable=*/false); 1231 Anon->setAccess(AS_public); 1232 if (getLangOptions().CPlusPlus) 1233 FieldCollector->Add(cast<FieldDecl>(Anon)); 1234 } else { 1235 VarDecl::StorageClass SC; 1236 switch (DS.getStorageClassSpec()) { 1237 default: assert(0 && "Unknown storage class!"); 1238 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1239 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1240 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1241 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1242 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1243 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1244 case DeclSpec::SCS_mutable: 1245 // mutable can only appear on non-static class members, so it's always 1246 // an error here 1247 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1248 Invalid = true; 1249 SC = VarDecl::None; 1250 break; 1251 } 1252 1253 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1254 /*IdentifierInfo=*/0, 1255 Context.getTypeDeclType(Record), 1256 SC, DS.getSourceRange().getBegin()); 1257 } 1258 Anon->setImplicit(); 1259 1260 // Add the anonymous struct/union object to the current 1261 // context. We'll be referencing this object when we refer to one of 1262 // its members. 1263 Owner->addDecl(Context, Anon); 1264 1265 // Inject the members of the anonymous struct/union into the owning 1266 // context and into the identifier resolver chain for name lookup 1267 // purposes. 1268 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1269 Invalid = true; 1270 1271 // Mark this as an anonymous struct/union type. Note that we do not 1272 // do this until after we have already checked and injected the 1273 // members of this anonymous struct/union type, because otherwise 1274 // the members could be injected twice: once by DeclContext when it 1275 // builds its lookup table, and once by 1276 // InjectAnonymousStructOrUnionMembers. 1277 Record->setAnonymousStructOrUnion(true); 1278 1279 if (Invalid) 1280 Anon->setInvalidDecl(); 1281 1282 return DeclPtrTy::make(Anon); 1283} 1284 1285 1286/// GetNameForDeclarator - Determine the full declaration name for the 1287/// given Declarator. 1288DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1289 switch (D.getKind()) { 1290 case Declarator::DK_Abstract: 1291 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1292 return DeclarationName(); 1293 1294 case Declarator::DK_Normal: 1295 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1296 return DeclarationName(D.getIdentifier()); 1297 1298 case Declarator::DK_Constructor: { 1299 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1300 Ty = Context.getCanonicalType(Ty); 1301 return Context.DeclarationNames.getCXXConstructorName(Ty); 1302 } 1303 1304 case Declarator::DK_Destructor: { 1305 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1306 Ty = Context.getCanonicalType(Ty); 1307 return Context.DeclarationNames.getCXXDestructorName(Ty); 1308 } 1309 1310 case Declarator::DK_Conversion: { 1311 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1312 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1313 Ty = Context.getCanonicalType(Ty); 1314 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1315 } 1316 1317 case Declarator::DK_Operator: 1318 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1319 return Context.DeclarationNames.getCXXOperatorName( 1320 D.getOverloadedOperator()); 1321 } 1322 1323 assert(false && "Unknown name kind"); 1324 return DeclarationName(); 1325} 1326 1327/// isNearlyMatchingFunction - Determine whether the C++ functions 1328/// Declaration and Definition are "nearly" matching. This heuristic 1329/// is used to improve diagnostics in the case where an out-of-line 1330/// function definition doesn't match any declaration within 1331/// the class or namespace. 1332static bool isNearlyMatchingFunction(ASTContext &Context, 1333 FunctionDecl *Declaration, 1334 FunctionDecl *Definition) { 1335 if (Declaration->param_size() != Definition->param_size()) 1336 return false; 1337 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1338 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1339 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1340 1341 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1342 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1343 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1344 return false; 1345 } 1346 1347 return true; 1348} 1349 1350Sema::DeclPtrTy 1351Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1352 DeclarationName Name = GetNameForDeclarator(D); 1353 1354 // All of these full declarators require an identifier. If it doesn't have 1355 // one, the ParsedFreeStandingDeclSpec action should be used. 1356 if (!Name) { 1357 if (!D.isInvalidType()) // Reject this if we think it is valid. 1358 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1359 diag::err_declarator_need_ident) 1360 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1361 return DeclPtrTy(); 1362 } 1363 1364 // The scope passed in may not be a decl scope. Zip up the scope tree until 1365 // we find one that is. 1366 while ((S->getFlags() & Scope::DeclScope) == 0 || 1367 (S->getFlags() & Scope::TemplateParamScope) != 0) 1368 S = S->getParent(); 1369 1370 DeclContext *DC; 1371 NamedDecl *PrevDecl; 1372 NamedDecl *New; 1373 1374 QualType R = GetTypeForDeclarator(D, S); 1375 1376 // See if this is a redefinition of a variable in the same scope. 1377 if (D.getCXXScopeSpec().isInvalid()) { 1378 DC = CurContext; 1379 PrevDecl = 0; 1380 D.setInvalidType(); 1381 } else if (!D.getCXXScopeSpec().isSet()) { 1382 LookupNameKind NameKind = LookupOrdinaryName; 1383 1384 // If the declaration we're planning to build will be a function 1385 // or object with linkage, then look for another declaration with 1386 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1387 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1388 /* Do nothing*/; 1389 else if (R->isFunctionType()) { 1390 if (CurContext->isFunctionOrMethod()) 1391 NameKind = LookupRedeclarationWithLinkage; 1392 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1393 NameKind = LookupRedeclarationWithLinkage; 1394 1395 DC = CurContext; 1396 PrevDecl = LookupName(S, Name, NameKind, true, 1397 D.getDeclSpec().getStorageClassSpec() != 1398 DeclSpec::SCS_static, 1399 D.getIdentifierLoc()); 1400 } else { // Something like "int foo::x;" 1401 DC = computeDeclContext(D.getCXXScopeSpec()); 1402 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1403 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1404 1405 // C++ 7.3.1.2p2: 1406 // Members (including explicit specializations of templates) of a named 1407 // namespace can also be defined outside that namespace by explicit 1408 // qualification of the name being defined, provided that the entity being 1409 // defined was already declared in the namespace and the definition appears 1410 // after the point of declaration in a namespace that encloses the 1411 // declarations namespace. 1412 // 1413 // Note that we only check the context at this point. We don't yet 1414 // have enough information to make sure that PrevDecl is actually 1415 // the declaration we want to match. For example, given: 1416 // 1417 // class X { 1418 // void f(); 1419 // void f(float); 1420 // }; 1421 // 1422 // void X::f(int) { } // ill-formed 1423 // 1424 // In this case, PrevDecl will point to the overload set 1425 // containing the two f's declared in X, but neither of them 1426 // matches. 1427 1428 // First check whether we named the global scope. 1429 if (isa<TranslationUnitDecl>(DC)) { 1430 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1431 << Name << D.getCXXScopeSpec().getRange(); 1432 } else if (!CurContext->Encloses(DC)) { 1433 // The qualifying scope doesn't enclose the original declaration. 1434 // Emit diagnostic based on current scope. 1435 SourceLocation L = D.getIdentifierLoc(); 1436 SourceRange R = D.getCXXScopeSpec().getRange(); 1437 if (isa<FunctionDecl>(CurContext)) 1438 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1439 else 1440 Diag(L, diag::err_invalid_declarator_scope) 1441 << Name << cast<NamedDecl>(DC) << R; 1442 D.setInvalidType(); 1443 } 1444 } 1445 1446 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1447 // Maybe we will complain about the shadowed template parameter. 1448 if (!D.isInvalidType()) 1449 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1450 D.setInvalidType(); 1451 1452 // Just pretend that we didn't see the previous declaration. 1453 PrevDecl = 0; 1454 } 1455 1456 // In C++, the previous declaration we find might be a tag type 1457 // (class or enum). In this case, the new declaration will hide the 1458 // tag type. Note that this does does not apply if we're declaring a 1459 // typedef (C++ [dcl.typedef]p4). 1460 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1461 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1462 PrevDecl = 0; 1463 1464 bool Redeclaration = false; 1465 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1466 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1467 } else if (R->isFunctionType()) { 1468 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1469 IsFunctionDefinition, Redeclaration); 1470 } else { 1471 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1472 } 1473 1474 if (New == 0) 1475 return DeclPtrTy(); 1476 1477 // If this has an identifier and is not an invalid redeclaration, 1478 // add it to the scope stack. 1479 if (Name && !(Redeclaration && New->isInvalidDecl())) 1480 PushOnScopeChains(New, S); 1481 1482 return DeclPtrTy::make(New); 1483} 1484 1485/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1486/// types into constant array types in certain situations which would otherwise 1487/// be errors (for GCC compatibility). 1488static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1489 ASTContext &Context, 1490 bool &SizeIsNegative) { 1491 // This method tries to turn a variable array into a constant 1492 // array even when the size isn't an ICE. This is necessary 1493 // for compatibility with code that depends on gcc's buggy 1494 // constant expression folding, like struct {char x[(int)(char*)2];} 1495 SizeIsNegative = false; 1496 1497 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1498 QualType Pointee = PTy->getPointeeType(); 1499 QualType FixedType = 1500 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1501 if (FixedType.isNull()) return FixedType; 1502 FixedType = Context.getPointerType(FixedType); 1503 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1504 return FixedType; 1505 } 1506 1507 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1508 if (!VLATy) 1509 return QualType(); 1510 // FIXME: We should probably handle this case 1511 if (VLATy->getElementType()->isVariablyModifiedType()) 1512 return QualType(); 1513 1514 Expr::EvalResult EvalResult; 1515 if (!VLATy->getSizeExpr() || 1516 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1517 !EvalResult.Val.isInt()) 1518 return QualType(); 1519 1520 llvm::APSInt &Res = EvalResult.Val.getInt(); 1521 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1522 return Context.getConstantArrayType(VLATy->getElementType(), 1523 Res, ArrayType::Normal, 0); 1524 1525 SizeIsNegative = true; 1526 return QualType(); 1527} 1528 1529/// \brief Register the given locally-scoped external C declaration so 1530/// that it can be found later for redeclarations 1531void 1532Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1533 Scope *S) { 1534 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1535 "Decl is not a locally-scoped decl!"); 1536 // Note that we have a locally-scoped external with this name. 1537 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1538 1539 if (!PrevDecl) 1540 return; 1541 1542 // If there was a previous declaration of this variable, it may be 1543 // in our identifier chain. Update the identifier chain with the new 1544 // declaration. 1545 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1546 // The previous declaration was found on the identifer resolver 1547 // chain, so remove it from its scope. 1548 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1549 S = S->getParent(); 1550 1551 if (S) 1552 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1553 } 1554} 1555 1556/// \brief Diagnose function specifiers on a declaration of an identifier that 1557/// does not identify a function. 1558void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1559 // FIXME: We should probably indicate the identifier in question to avoid 1560 // confusion for constructs like "inline int a(), b;" 1561 if (D.getDeclSpec().isInlineSpecified()) 1562 Diag(D.getDeclSpec().getInlineSpecLoc(), 1563 diag::err_inline_non_function); 1564 1565 if (D.getDeclSpec().isVirtualSpecified()) 1566 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1567 diag::err_virtual_non_function); 1568 1569 if (D.getDeclSpec().isExplicitSpecified()) 1570 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1571 diag::err_explicit_non_function); 1572} 1573 1574NamedDecl* 1575Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1576 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1577 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1578 if (D.getCXXScopeSpec().isSet()) { 1579 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1580 << D.getCXXScopeSpec().getRange(); 1581 D.setInvalidType(); 1582 // Pretend we didn't see the scope specifier. 1583 DC = 0; 1584 } 1585 1586 if (getLangOptions().CPlusPlus) { 1587 // Check that there are no default arguments (C++ only). 1588 CheckExtraCXXDefaultArguments(D); 1589 } 1590 1591 DiagnoseFunctionSpecifiers(D); 1592 1593 if (D.getDeclSpec().isThreadSpecified()) 1594 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1595 1596 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1597 if (!NewTD) return 0; 1598 1599 if (D.isInvalidType()) 1600 NewTD->setInvalidDecl(); 1601 1602 // Handle attributes prior to checking for duplicates in MergeVarDecl 1603 ProcessDeclAttributes(NewTD, D); 1604 // Merge the decl with the existing one if appropriate. If the decl is 1605 // in an outer scope, it isn't the same thing. 1606 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1607 Redeclaration = true; 1608 MergeTypeDefDecl(NewTD, PrevDecl); 1609 } 1610 1611 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1612 // then it shall have block scope. 1613 QualType T = NewTD->getUnderlyingType(); 1614 if (T->isVariablyModifiedType()) { 1615 CurFunctionNeedsScopeChecking = true; 1616 1617 if (S->getFnParent() == 0) { 1618 bool SizeIsNegative; 1619 QualType FixedTy = 1620 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1621 if (!FixedTy.isNull()) { 1622 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1623 NewTD->setUnderlyingType(FixedTy); 1624 } else { 1625 if (SizeIsNegative) 1626 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1627 else if (T->isVariableArrayType()) 1628 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1629 else 1630 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1631 NewTD->setInvalidDecl(); 1632 } 1633 } 1634 } 1635 return NewTD; 1636} 1637 1638/// \brief Determines whether the given declaration is an out-of-scope 1639/// previous declaration. 1640/// 1641/// This routine should be invoked when name lookup has found a 1642/// previous declaration (PrevDecl) that is not in the scope where a 1643/// new declaration by the same name is being introduced. If the new 1644/// declaration occurs in a local scope, previous declarations with 1645/// linkage may still be considered previous declarations (C99 1646/// 6.2.2p4-5, C++ [basic.link]p6). 1647/// 1648/// \param PrevDecl the previous declaration found by name 1649/// lookup 1650/// 1651/// \param DC the context in which the new declaration is being 1652/// declared. 1653/// 1654/// \returns true if PrevDecl is an out-of-scope previous declaration 1655/// for a new delcaration with the same name. 1656static bool 1657isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1658 ASTContext &Context) { 1659 if (!PrevDecl) 1660 return 0; 1661 1662 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1663 // case we need to check each of the overloaded functions. 1664 if (!PrevDecl->hasLinkage()) 1665 return false; 1666 1667 if (Context.getLangOptions().CPlusPlus) { 1668 // C++ [basic.link]p6: 1669 // If there is a visible declaration of an entity with linkage 1670 // having the same name and type, ignoring entities declared 1671 // outside the innermost enclosing namespace scope, the block 1672 // scope declaration declares that same entity and receives the 1673 // linkage of the previous declaration. 1674 DeclContext *OuterContext = DC->getLookupContext(); 1675 if (!OuterContext->isFunctionOrMethod()) 1676 // This rule only applies to block-scope declarations. 1677 return false; 1678 else { 1679 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1680 if (PrevOuterContext->isRecord()) 1681 // We found a member function: ignore it. 1682 return false; 1683 else { 1684 // Find the innermost enclosing namespace for the new and 1685 // previous declarations. 1686 while (!OuterContext->isFileContext()) 1687 OuterContext = OuterContext->getParent(); 1688 while (!PrevOuterContext->isFileContext()) 1689 PrevOuterContext = PrevOuterContext->getParent(); 1690 1691 // The previous declaration is in a different namespace, so it 1692 // isn't the same function. 1693 if (OuterContext->getPrimaryContext() != 1694 PrevOuterContext->getPrimaryContext()) 1695 return false; 1696 } 1697 } 1698 } 1699 1700 return true; 1701} 1702 1703NamedDecl* 1704Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1705 QualType R,NamedDecl* PrevDecl, 1706 bool &Redeclaration) { 1707 DeclarationName Name = GetNameForDeclarator(D); 1708 1709 // Check that there are no default arguments (C++ only). 1710 if (getLangOptions().CPlusPlus) 1711 CheckExtraCXXDefaultArguments(D); 1712 1713 VarDecl *NewVD; 1714 VarDecl::StorageClass SC; 1715 switch (D.getDeclSpec().getStorageClassSpec()) { 1716 default: assert(0 && "Unknown storage class!"); 1717 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1718 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1719 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1720 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1721 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1722 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1723 case DeclSpec::SCS_mutable: 1724 // mutable can only appear on non-static class members, so it's always 1725 // an error here 1726 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1727 D.setInvalidType(); 1728 SC = VarDecl::None; 1729 break; 1730 } 1731 1732 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1733 if (!II) { 1734 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1735 << Name.getAsString(); 1736 return 0; 1737 } 1738 1739 DiagnoseFunctionSpecifiers(D); 1740 1741 if (!DC->isRecord() && S->getFnParent() == 0) { 1742 // C99 6.9p2: The storage-class specifiers auto and register shall not 1743 // appear in the declaration specifiers in an external declaration. 1744 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1745 1746 // If this is a register variable with an asm label specified, then this 1747 // is a GNU extension. 1748 if (SC == VarDecl::Register && D.getAsmLabel()) 1749 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1750 else 1751 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1752 D.setInvalidType(); 1753 } 1754 } 1755 if (DC->isRecord() && !CurContext->isRecord()) { 1756 // This is an out-of-line definition of a static data member. 1757 if (SC == VarDecl::Static) { 1758 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1759 diag::err_static_out_of_line) 1760 << CodeModificationHint::CreateRemoval( 1761 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1762 } else if (SC == VarDecl::None) 1763 SC = VarDecl::Static; 1764 } 1765 1766 // The variable can not 1767 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1768 II, R, SC, 1769 // FIXME: Move to DeclGroup... 1770 D.getDeclSpec().getSourceRange().getBegin()); 1771 1772 if (D.isInvalidType()) 1773 NewVD->setInvalidDecl(); 1774 1775 if (D.getDeclSpec().isThreadSpecified()) { 1776 if (NewVD->hasLocalStorage()) 1777 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1778 else if (!Context.Target.isTLSSupported()) 1779 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1780 else 1781 NewVD->setThreadSpecified(true); 1782 } 1783 1784 // Set the lexical context. If the declarator has a C++ scope specifier, the 1785 // lexical context will be different from the semantic context. 1786 NewVD->setLexicalDeclContext(CurContext); 1787 1788 // Handle attributes prior to checking for duplicates in MergeVarDecl 1789 ProcessDeclAttributes(NewVD, D); 1790 1791 // Handle GNU asm-label extension (encoded as an attribute). 1792 if (Expr *E = (Expr*) D.getAsmLabel()) { 1793 // The parser guarantees this is a string. 1794 StringLiteral *SE = cast<StringLiteral>(E); 1795 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1796 SE->getByteLength()))); 1797 } 1798 1799 // If name lookup finds a previous declaration that is not in the 1800 // same scope as the new declaration, this may still be an 1801 // acceptable redeclaration. 1802 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1803 !(NewVD->hasLinkage() && 1804 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1805 PrevDecl = 0; 1806 1807 // Merge the decl with the existing one if appropriate. 1808 if (PrevDecl) { 1809 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1810 // The user tried to define a non-static data member 1811 // out-of-line (C++ [dcl.meaning]p1). 1812 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1813 << D.getCXXScopeSpec().getRange(); 1814 PrevDecl = 0; 1815 NewVD->setInvalidDecl(); 1816 } 1817 } else if (D.getCXXScopeSpec().isSet()) { 1818 // No previous declaration in the qualifying scope. 1819 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1820 << Name << D.getCXXScopeSpec().getRange(); 1821 NewVD->setInvalidDecl(); 1822 } 1823 1824 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1825 1826 // If this is a locally-scoped extern C variable, update the map of 1827 // such variables. 1828 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1829 !NewVD->isInvalidDecl()) 1830 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1831 1832 return NewVD; 1833} 1834 1835/// \brief Perform semantic checking on a newly-created variable 1836/// declaration. 1837/// 1838/// This routine performs all of the type-checking required for a 1839/// variable declaration once it has been built. It is used both to 1840/// check variables after they have been parsed and their declarators 1841/// have been translated into a declaration, and to check variables 1842/// that have been instantiated from a template. 1843/// 1844/// Sets NewVD->isInvalidDecl() if an error was encountered. 1845void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1846 bool &Redeclaration) { 1847 // If the decl is already known invalid, don't check it. 1848 if (NewVD->isInvalidDecl()) 1849 return; 1850 1851 QualType T = NewVD->getType(); 1852 1853 if (T->isObjCInterfaceType()) { 1854 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1855 return NewVD->setInvalidDecl(); 1856 } 1857 1858 // The variable can not have an abstract class type. 1859 if (RequireNonAbstractType(NewVD->getLocation(), T, 1860 diag::err_abstract_type_in_decl, 1861 AbstractVariableType)) 1862 return NewVD->setInvalidDecl(); 1863 1864 // Emit an error if an address space was applied to decl with local storage. 1865 // This includes arrays of objects with address space qualifiers, but not 1866 // automatic variables that point to other address spaces. 1867 // ISO/IEC TR 18037 S5.1.2 1868 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1869 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1870 return NewVD->setInvalidDecl(); 1871 } 1872 1873 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1874 && !NewVD->hasAttr<BlocksAttr>()) 1875 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1876 1877 bool isVM = T->isVariablyModifiedType(); 1878 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1879 CurFunctionNeedsScopeChecking = true; 1880 1881 if ((isVM && NewVD->hasLinkage()) || 1882 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1883 bool SizeIsNegative; 1884 QualType FixedTy = 1885 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1886 1887 if (FixedTy.isNull() && T->isVariableArrayType()) { 1888 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1889 // FIXME: This won't give the correct result for 1890 // int a[10][n]; 1891 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1892 1893 if (NewVD->isFileVarDecl()) 1894 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1895 << SizeRange; 1896 else if (NewVD->getStorageClass() == VarDecl::Static) 1897 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1898 << SizeRange; 1899 else 1900 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1901 << SizeRange; 1902 return NewVD->setInvalidDecl(); 1903 } 1904 1905 if (FixedTy.isNull()) { 1906 if (NewVD->isFileVarDecl()) 1907 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1908 else 1909 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1910 return NewVD->setInvalidDecl(); 1911 } 1912 1913 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1914 NewVD->setType(FixedTy); 1915 } 1916 1917 if (!PrevDecl && NewVD->isExternC(Context)) { 1918 // Since we did not find anything by this name and we're declaring 1919 // an extern "C" variable, look for a non-visible extern "C" 1920 // declaration with the same name. 1921 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1922 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1923 if (Pos != LocallyScopedExternalDecls.end()) 1924 PrevDecl = Pos->second; 1925 } 1926 1927 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1928 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1929 << T; 1930 return NewVD->setInvalidDecl(); 1931 } 1932 1933 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 1934 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 1935 return NewVD->setInvalidDecl(); 1936 } 1937 1938 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 1939 Diag(NewVD->getLocation(), diag::err_block_on_vm); 1940 return NewVD->setInvalidDecl(); 1941 } 1942 1943 if (PrevDecl) { 1944 Redeclaration = true; 1945 MergeVarDecl(NewVD, PrevDecl); 1946 } 1947} 1948 1949NamedDecl* 1950Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1951 QualType R, NamedDecl* PrevDecl, 1952 bool IsFunctionDefinition, bool &Redeclaration) { 1953 assert(R.getTypePtr()->isFunctionType()); 1954 1955 DeclarationName Name = GetNameForDeclarator(D); 1956 FunctionDecl::StorageClass SC = FunctionDecl::None; 1957 switch (D.getDeclSpec().getStorageClassSpec()) { 1958 default: assert(0 && "Unknown storage class!"); 1959 case DeclSpec::SCS_auto: 1960 case DeclSpec::SCS_register: 1961 case DeclSpec::SCS_mutable: 1962 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1963 diag::err_typecheck_sclass_func); 1964 D.setInvalidType(); 1965 break; 1966 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1967 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1968 case DeclSpec::SCS_static: { 1969 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1970 // C99 6.7.1p5: 1971 // The declaration of an identifier for a function that has 1972 // block scope shall have no explicit storage-class specifier 1973 // other than extern 1974 // See also (C++ [dcl.stc]p4). 1975 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1976 diag::err_static_block_func); 1977 SC = FunctionDecl::None; 1978 } else 1979 SC = FunctionDecl::Static; 1980 break; 1981 } 1982 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1983 } 1984 1985 if (D.getDeclSpec().isThreadSpecified()) 1986 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1987 1988 bool isInline = D.getDeclSpec().isInlineSpecified(); 1989 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1990 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1991 1992 // Check that the return type is not an abstract class type. 1993 // For record types, this is done by the AbstractClassUsageDiagnoser once 1994 // the class has been completely parsed. 1995 if (!DC->isRecord() && 1996 RequireNonAbstractType(D.getIdentifierLoc(), 1997 R->getAsFunctionType()->getResultType(), 1998 diag::err_abstract_type_in_decl, 1999 AbstractReturnType)) 2000 D.setInvalidType(); 2001 2002 // Do not allow returning a objc interface by-value. 2003 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2004 Diag(D.getIdentifierLoc(), 2005 diag::err_object_cannot_be_passed_returned_by_value) << 0 2006 << R->getAsFunctionType()->getResultType(); 2007 D.setInvalidType(); 2008 } 2009 2010 bool isVirtualOkay = false; 2011 FunctionDecl *NewFD; 2012 if (D.getKind() == Declarator::DK_Constructor) { 2013 // This is a C++ constructor declaration. 2014 assert(DC->isRecord() && 2015 "Constructors can only be declared in a member context"); 2016 2017 R = CheckConstructorDeclarator(D, R, SC); 2018 2019 // Create the new declaration 2020 NewFD = CXXConstructorDecl::Create(Context, 2021 cast<CXXRecordDecl>(DC), 2022 D.getIdentifierLoc(), Name, R, 2023 isExplicit, isInline, 2024 /*isImplicitlyDeclared=*/false); 2025 } else if (D.getKind() == Declarator::DK_Destructor) { 2026 // This is a C++ destructor declaration. 2027 if (DC->isRecord()) { 2028 R = CheckDestructorDeclarator(D, SC); 2029 2030 NewFD = CXXDestructorDecl::Create(Context, 2031 cast<CXXRecordDecl>(DC), 2032 D.getIdentifierLoc(), Name, R, 2033 isInline, 2034 /*isImplicitlyDeclared=*/false); 2035 2036 isVirtualOkay = true; 2037 } else { 2038 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2039 2040 // Create a FunctionDecl to satisfy the function definition parsing 2041 // code path. 2042 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2043 Name, R, SC, isInline, 2044 /*hasPrototype=*/true, 2045 // FIXME: Move to DeclGroup... 2046 D.getDeclSpec().getSourceRange().getBegin()); 2047 D.setInvalidType(); 2048 } 2049 } else if (D.getKind() == Declarator::DK_Conversion) { 2050 if (!DC->isRecord()) { 2051 Diag(D.getIdentifierLoc(), 2052 diag::err_conv_function_not_member); 2053 return 0; 2054 } 2055 2056 CheckConversionDeclarator(D, R, SC); 2057 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2058 D.getIdentifierLoc(), Name, R, 2059 isInline, isExplicit); 2060 2061 isVirtualOkay = true; 2062 } else if (DC->isRecord()) { 2063 // If the of the function is the same as the name of the record, then this 2064 // must be an invalid constructor that has a return type. 2065 // (The parser checks for a return type and makes the declarator a 2066 // constructor if it has no return type). 2067 // must have an invalid constructor that has a return type 2068 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2069 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2070 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2071 << SourceRange(D.getIdentifierLoc()); 2072 return 0; 2073 } 2074 2075 // This is a C++ method declaration. 2076 2077 // FIXME: All inline method declarations are semantically inline. We 2078 // should add a new bit to keep track of whether they were declared with an 2079 // inline keyword as well. 2080 if (CurContext == DC && IsFunctionDefinition) 2081 isInline = true; 2082 2083 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2084 D.getIdentifierLoc(), Name, R, 2085 (SC == FunctionDecl::Static), isInline); 2086 2087 isVirtualOkay = (SC != FunctionDecl::Static); 2088 } else { 2089 // Determine whether the function was written with a 2090 // prototype. This true when: 2091 // - we're in C++ (where every function has a prototype), 2092 // - there is a prototype in the declarator, or 2093 // - the type R of the function is some kind of typedef or other reference 2094 // to a type name (which eventually refers to a function type). 2095 bool HasPrototype = 2096 getLangOptions().CPlusPlus || 2097 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2098 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2099 2100 NewFD = FunctionDecl::Create(Context, DC, 2101 D.getIdentifierLoc(), 2102 Name, R, SC, isInline, HasPrototype, 2103 // FIXME: Move to DeclGroup... 2104 D.getDeclSpec().getSourceRange().getBegin()); 2105 } 2106 2107 if (D.isInvalidType()) 2108 NewFD->setInvalidDecl(); 2109 2110 // Set the lexical context. If the declarator has a C++ 2111 // scope specifier, the lexical context will be different 2112 // from the semantic context. 2113 NewFD->setLexicalDeclContext(CurContext); 2114 2115 // C++ [dcl.fct.spec]p5: 2116 // The virtual specifier shall only be used in declarations of 2117 // nonstatic class member functions that appear within a 2118 // member-specification of a class declaration; see 10.3. 2119 // 2120 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2121 // function is also virtual if it overrides an already virtual 2122 // function. This is important to do here because it's part of the 2123 // declaration. 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)->setVirtual(); 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 (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2145 !CurContext->isRecord()) { 2146 // C++ [class.static]p1: 2147 // A data or function member of a class may be declared static 2148 // in a class definition, in which case it is a static member of 2149 // the class. 2150 2151 // Complain about the 'static' specifier if it's on an out-of-line 2152 // member function definition. 2153 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2154 diag::err_static_out_of_line) 2155 << CodeModificationHint::CreateRemoval( 2156 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2157 } 2158 2159 // Handle GNU asm-label extension (encoded as an attribute). 2160 if (Expr *E = (Expr*) D.getAsmLabel()) { 2161 // The parser guarantees this is a string. 2162 StringLiteral *SE = cast<StringLiteral>(E); 2163 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2164 SE->getByteLength()))); 2165 } 2166 2167 // Copy the parameter declarations from the declarator D to the function 2168 // declaration NewFD, if they are available. First scavenge them into Params. 2169 llvm::SmallVector<ParmVarDecl*, 16> Params; 2170 if (D.getNumTypeObjects() > 0) { 2171 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2172 2173 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2174 // function that takes no arguments, not a function that takes a 2175 // single void argument. 2176 // We let through "const void" here because Sema::GetTypeForDeclarator 2177 // already checks for that case. 2178 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2179 FTI.ArgInfo[0].Param && 2180 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2181 // Empty arg list, don't push any params. 2182 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2183 2184 // In C++, the empty parameter-type-list must be spelled "void"; a 2185 // typedef of void is not permitted. 2186 if (getLangOptions().CPlusPlus && 2187 Param->getType().getUnqualifiedType() != Context.VoidTy) 2188 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2189 // FIXME: Leaks decl? 2190 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2191 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2192 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2193 } 2194 2195 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2196 // When we're declaring a function with a typedef, typeof, etc as in the 2197 // following example, we'll need to synthesize (unnamed) 2198 // parameters for use in the declaration. 2199 // 2200 // @code 2201 // typedef void fn(int); 2202 // fn f; 2203 // @endcode 2204 2205 // Synthesize a parameter for each argument type. 2206 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2207 AE = FT->arg_type_end(); AI != AE; ++AI) { 2208 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2209 SourceLocation(), 0, 2210 *AI, VarDecl::None, 0); 2211 Param->setImplicit(); 2212 Params.push_back(Param); 2213 } 2214 } else { 2215 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2216 "Should not need args for typedef of non-prototype fn"); 2217 } 2218 // Finally, we know we have the right number of parameters, install them. 2219 NewFD->setParams(Context, &Params[0], Params.size()); 2220 2221 2222 2223 // If name lookup finds a previous declaration that is not in the 2224 // same scope as the new declaration, this may still be an 2225 // acceptable redeclaration. 2226 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2227 !(NewFD->hasLinkage() && 2228 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2229 PrevDecl = 0; 2230 2231 // Perform semantic checking on the function declaration. 2232 bool OverloadableAttrRequired = false; // FIXME: HACK! 2233 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2234 /*FIXME:*/OverloadableAttrRequired); 2235 2236 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2237 // An out-of-line member function declaration must also be a 2238 // definition (C++ [dcl.meaning]p1). 2239 if (!IsFunctionDefinition) { 2240 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2241 << D.getCXXScopeSpec().getRange(); 2242 NewFD->setInvalidDecl(); 2243 } else if (!Redeclaration) { 2244 // The user tried to provide an out-of-line definition for a 2245 // function that is a member of a class or namespace, but there 2246 // was no such member function declared (C++ [class.mfct]p2, 2247 // C++ [namespace.memdef]p2). For example: 2248 // 2249 // class X { 2250 // void f() const; 2251 // }; 2252 // 2253 // void X::f() { } // ill-formed 2254 // 2255 // Complain about this problem, and attempt to suggest close 2256 // matches (e.g., those that differ only in cv-qualifiers and 2257 // whether the parameter types are references). 2258 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2259 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2260 NewFD->setInvalidDecl(); 2261 2262 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2263 true); 2264 assert(!Prev.isAmbiguous() && 2265 "Cannot have an ambiguity in previous-declaration lookup"); 2266 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2267 Func != FuncEnd; ++Func) { 2268 if (isa<FunctionDecl>(*Func) && 2269 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2270 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2271 } 2272 2273 PrevDecl = 0; 2274 } 2275 } 2276 2277 // Handle attributes. We need to have merged decls when handling attributes 2278 // (for example to check for conflicts, etc). 2279 // FIXME: This needs to happen before we merge declarations. Then, 2280 // let attribute merging cope with attribute conflicts. 2281 ProcessDeclAttributes(NewFD, D); 2282 AddKnownFunctionAttributes(NewFD); 2283 2284 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2285 // If a function name is overloadable in C, then every function 2286 // with that name must be marked "overloadable". 2287 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2288 << Redeclaration << NewFD; 2289 if (PrevDecl) 2290 Diag(PrevDecl->getLocation(), 2291 diag::note_attribute_overloadable_prev_overload); 2292 NewFD->addAttr(::new (Context) OverloadableAttr()); 2293 } 2294 2295 // If this is a locally-scoped extern C function, update the 2296 // map of such names. 2297 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2298 && !NewFD->isInvalidDecl()) 2299 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2300 2301 return NewFD; 2302} 2303 2304/// \brief Perform semantic checking of a new function declaration. 2305/// 2306/// Performs semantic analysis of the new function declaration 2307/// NewFD. This routine performs all semantic checking that does not 2308/// require the actual declarator involved in the declaration, and is 2309/// used both for the declaration of functions as they are parsed 2310/// (called via ActOnDeclarator) and for the declaration of functions 2311/// that have been instantiated via C++ template instantiation (called 2312/// via InstantiateDecl). 2313/// 2314/// This sets NewFD->isInvalidDecl() to true if there was an error. 2315void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2316 bool &Redeclaration, 2317 bool &OverloadableAttrRequired) { 2318 // If NewFD is already known erroneous, don't do any of this checking. 2319 if (NewFD->isInvalidDecl()) 2320 return; 2321 2322 // Semantic checking for this function declaration (in isolation). 2323 if (getLangOptions().CPlusPlus) { 2324 // C++-specific checks. 2325 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2326 CheckConstructor(Constructor); 2327 } else if (isa<CXXDestructorDecl>(NewFD)) { 2328 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2329 Record->setUserDeclaredDestructor(true); 2330 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2331 // user-defined destructor. 2332 Record->setPOD(false); 2333 2334 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2335 // declared destructor. 2336 Record->setHasTrivialDestructor(false); 2337 } else if (CXXConversionDecl *Conversion 2338 = dyn_cast<CXXConversionDecl>(NewFD)) 2339 ActOnConversionDeclarator(Conversion); 2340 2341 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2342 if (NewFD->isOverloadedOperator() && 2343 CheckOverloadedOperatorDeclaration(NewFD)) 2344 return NewFD->setInvalidDecl(); 2345 } 2346 2347 // C99 6.7.4p6: 2348 // [... ] For a function with external linkage, the following 2349 // restrictions apply: [...] If all of the file scope declarations 2350 // for a function in a translation unit include the inline 2351 // function specifier without extern, then the definition in that 2352 // translation unit is an inline definition. An inline definition 2353 // does not provide an external definition for the function, and 2354 // does not forbid an external definition in another translation 2355 // unit. 2356 // 2357 // Here we determine whether this function, in isolation, would be a 2358 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2359 // previous declarations. 2360 if (NewFD->isInline() && getLangOptions().C99 && 2361 NewFD->getStorageClass() == FunctionDecl::None && 2362 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2363 NewFD->setC99InlineDefinition(true); 2364 2365 // Check for a previous declaration of this name. 2366 if (!PrevDecl && NewFD->isExternC(Context)) { 2367 // Since we did not find anything by this name and we're declaring 2368 // an extern "C" function, look for a non-visible extern "C" 2369 // declaration with the same name. 2370 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2371 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2372 if (Pos != LocallyScopedExternalDecls.end()) 2373 PrevDecl = Pos->second; 2374 } 2375 2376 // Merge or overload the declaration with an existing declaration of 2377 // the same name, if appropriate. 2378 if (PrevDecl) { 2379 // Determine whether NewFD is an overload of PrevDecl or 2380 // a declaration that requires merging. If it's an overload, 2381 // there's no more work to do here; we'll just add the new 2382 // function to the scope. 2383 OverloadedFunctionDecl::function_iterator MatchedDecl; 2384 2385 if (!getLangOptions().CPlusPlus && 2386 AllowOverloadingOfFunction(PrevDecl, Context)) { 2387 OverloadableAttrRequired = true; 2388 2389 // Functions marked "overloadable" must have a prototype (that 2390 // we can't get through declaration merging). 2391 if (!NewFD->getType()->getAsFunctionProtoType()) { 2392 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2393 << NewFD; 2394 Redeclaration = true; 2395 2396 // Turn this into a variadic function with no parameters. 2397 QualType R = Context.getFunctionType( 2398 NewFD->getType()->getAsFunctionType()->getResultType(), 2399 0, 0, true, 0); 2400 NewFD->setType(R); 2401 return NewFD->setInvalidDecl(); 2402 } 2403 } 2404 2405 if (PrevDecl && 2406 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2407 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2408 Redeclaration = true; 2409 Decl *OldDecl = PrevDecl; 2410 2411 // If PrevDecl was an overloaded function, extract the 2412 // FunctionDecl that matched. 2413 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2414 OldDecl = *MatchedDecl; 2415 2416 // NewFD and OldDecl represent declarations that need to be 2417 // merged. 2418 if (MergeFunctionDecl(NewFD, OldDecl)) 2419 return NewFD->setInvalidDecl(); 2420 2421 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2422 } 2423 } 2424 2425 // In C++, check default arguments now that we have merged decls. Unless 2426 // the lexical context is the class, because in this case this is done 2427 // during delayed parsing anyway. 2428 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2429 CheckCXXDefaultArguments(NewFD); 2430} 2431 2432bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2433 // FIXME: Need strict checking. In C89, we need to check for 2434 // any assignment, increment, decrement, function-calls, or 2435 // commas outside of a sizeof. In C99, it's the same list, 2436 // except that the aforementioned are allowed in unevaluated 2437 // expressions. Everything else falls under the 2438 // "may accept other forms of constant expressions" exception. 2439 // (We never end up here for C++, so the constant expression 2440 // rules there don't matter.) 2441 if (Init->isConstantInitializer(Context)) 2442 return false; 2443 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2444 << Init->getSourceRange(); 2445 return true; 2446} 2447 2448void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2449 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2450} 2451 2452/// AddInitializerToDecl - Adds the initializer Init to the 2453/// declaration dcl. If DirectInit is true, this is C++ direct 2454/// initialization rather than copy initialization. 2455void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2456 Decl *RealDecl = dcl.getAs<Decl>(); 2457 // If there is no declaration, there was an error parsing it. Just ignore 2458 // the initializer. 2459 if (RealDecl == 0) 2460 return; 2461 2462 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2463 // With declarators parsed the way they are, the parser cannot 2464 // distinguish between a normal initializer and a pure-specifier. 2465 // Thus this grotesque test. 2466 IntegerLiteral *IL; 2467 Expr *Init = static_cast<Expr *>(init.get()); 2468 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2469 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2470 if (Method->isVirtual()) { 2471 Method->setPure(); 2472 2473 // A class is abstract if at least one function is pure virtual. 2474 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2475 } else if (!Method->isInvalidDecl()) { 2476 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2477 << Method->getDeclName() << Init->getSourceRange(); 2478 Method->setInvalidDecl(); 2479 } 2480 } else { 2481 Diag(Method->getLocation(), diag::err_member_function_initialization) 2482 << Method->getDeclName() << Init->getSourceRange(); 2483 Method->setInvalidDecl(); 2484 } 2485 return; 2486 } 2487 2488 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2489 if (!VDecl) { 2490 if (getLangOptions().CPlusPlus && 2491 RealDecl->getLexicalDeclContext()->isRecord() && 2492 isa<NamedDecl>(RealDecl)) 2493 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2494 << cast<NamedDecl>(RealDecl)->getDeclName(); 2495 else 2496 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2497 RealDecl->setInvalidDecl(); 2498 return; 2499 } 2500 2501 if (!VDecl->getType()->isArrayType() && 2502 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2503 diag::err_typecheck_decl_incomplete_type)) { 2504 RealDecl->setInvalidDecl(); 2505 return; 2506 } 2507 2508 const VarDecl *Def = 0; 2509 if (VDecl->getDefinition(Def)) { 2510 Diag(VDecl->getLocation(), diag::err_redefinition) 2511 << VDecl->getDeclName(); 2512 Diag(Def->getLocation(), diag::note_previous_definition); 2513 VDecl->setInvalidDecl(); 2514 return; 2515 } 2516 2517 // Take ownership of the expression, now that we're sure we have somewhere 2518 // to put it. 2519 Expr *Init = init.takeAs<Expr>(); 2520 assert(Init && "missing initializer"); 2521 2522 // Get the decls type and save a reference for later, since 2523 // CheckInitializerTypes may change it. 2524 QualType DclT = VDecl->getType(), SavT = DclT; 2525 if (VDecl->isBlockVarDecl()) { 2526 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2527 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2528 VDecl->setInvalidDecl(); 2529 } else if (!VDecl->isInvalidDecl()) { 2530 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2531 VDecl->getDeclName(), DirectInit)) 2532 VDecl->setInvalidDecl(); 2533 2534 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2535 // Don't check invalid declarations to avoid emitting useless diagnostics. 2536 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2537 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2538 CheckForConstantInitializer(Init, DclT); 2539 } 2540 } 2541 } else if (VDecl->isStaticDataMember() && 2542 VDecl->getLexicalDeclContext()->isRecord()) { 2543 // This is an in-class initialization for a static data member, e.g., 2544 // 2545 // struct S { 2546 // static const int value = 17; 2547 // }; 2548 2549 // Attach the initializer 2550 VDecl->setInit(Init); 2551 2552 // C++ [class.mem]p4: 2553 // A member-declarator can contain a constant-initializer only 2554 // if it declares a static member (9.4) of const integral or 2555 // const enumeration type, see 9.4.2. 2556 QualType T = VDecl->getType(); 2557 if (!T->isDependentType() && 2558 (!Context.getCanonicalType(T).isConstQualified() || 2559 !T->isIntegralType())) { 2560 Diag(VDecl->getLocation(), diag::err_member_initialization) 2561 << VDecl->getDeclName() << Init->getSourceRange(); 2562 VDecl->setInvalidDecl(); 2563 } else { 2564 // C++ [class.static.data]p4: 2565 // If a static data member is of const integral or const 2566 // enumeration type, its declaration in the class definition 2567 // can specify a constant-initializer which shall be an 2568 // integral constant expression (5.19). 2569 if (!Init->isTypeDependent() && 2570 !Init->getType()->isIntegralType()) { 2571 // We have a non-dependent, non-integral or enumeration type. 2572 Diag(Init->getSourceRange().getBegin(), 2573 diag::err_in_class_initializer_non_integral_type) 2574 << Init->getType() << Init->getSourceRange(); 2575 VDecl->setInvalidDecl(); 2576 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2577 // Check whether the expression is a constant expression. 2578 llvm::APSInt Value; 2579 SourceLocation Loc; 2580 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2581 Diag(Loc, diag::err_in_class_initializer_non_constant) 2582 << Init->getSourceRange(); 2583 VDecl->setInvalidDecl(); 2584 } else if (!VDecl->getType()->isDependentType()) 2585 ImpCastExprToType(Init, VDecl->getType()); 2586 } 2587 } 2588 } else if (VDecl->isFileVarDecl()) { 2589 if (VDecl->getStorageClass() == VarDecl::Extern) 2590 Diag(VDecl->getLocation(), diag::warn_extern_init); 2591 if (!VDecl->isInvalidDecl()) 2592 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2593 VDecl->getDeclName(), DirectInit)) 2594 VDecl->setInvalidDecl(); 2595 2596 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2597 // Don't check invalid declarations to avoid emitting useless diagnostics. 2598 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2599 // C99 6.7.8p4. All file scoped initializers need to be constant. 2600 CheckForConstantInitializer(Init, DclT); 2601 } 2602 } 2603 // If the type changed, it means we had an incomplete type that was 2604 // completed by the initializer. For example: 2605 // int ary[] = { 1, 3, 5 }; 2606 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2607 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2608 VDecl->setType(DclT); 2609 Init->setType(DclT); 2610 } 2611 2612 // Attach the initializer to the decl. 2613 VDecl->setInit(Init); 2614 2615 // If the previous declaration of VDecl was a tentative definition, 2616 // remove it from the set of tentative definitions. 2617 if (VDecl->getPreviousDeclaration() && 2618 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2619 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2620 = TentativeDefinitions.find(VDecl->getDeclName()); 2621 assert(Pos != TentativeDefinitions.end() && 2622 "Unrecorded tentative definition?"); 2623 TentativeDefinitions.erase(Pos); 2624 } 2625 2626 return; 2627} 2628 2629void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2630 Decl *RealDecl = dcl.getAs<Decl>(); 2631 2632 // If there is no declaration, there was an error parsing it. Just ignore it. 2633 if (RealDecl == 0) 2634 return; 2635 2636 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2637 QualType Type = Var->getType(); 2638 2639 // Record tentative definitions. 2640 if (Var->isTentativeDefinition(Context)) 2641 TentativeDefinitions[Var->getDeclName()] = Var; 2642 2643 // C++ [dcl.init.ref]p3: 2644 // The initializer can be omitted for a reference only in a 2645 // parameter declaration (8.3.5), in the declaration of a 2646 // function return type, in the declaration of a class member 2647 // within its class declaration (9.2), and where the extern 2648 // specifier is explicitly used. 2649 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2650 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2651 << Var->getDeclName() 2652 << SourceRange(Var->getLocation(), Var->getLocation()); 2653 Var->setInvalidDecl(); 2654 return; 2655 } 2656 2657 // C++ [dcl.init]p9: 2658 // 2659 // If no initializer is specified for an object, and the object 2660 // is of (possibly cv-qualified) non-POD class type (or array 2661 // thereof), the object shall be default-initialized; if the 2662 // object is of const-qualified type, the underlying class type 2663 // shall have a user-declared default constructor. 2664 if (getLangOptions().CPlusPlus) { 2665 QualType InitType = Type; 2666 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2667 InitType = Array->getElementType(); 2668 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2669 CXXRecordDecl *RD = 2670 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2671 CXXConstructorDecl *Constructor = 0; 2672 if (!RequireCompleteType(Var->getLocation(), InitType, 2673 diag::err_invalid_incomplete_type_use)) 2674 Constructor 2675 = PerformInitializationByConstructor(InitType, 0, 0, 2676 Var->getLocation(), 2677 SourceRange(Var->getLocation(), 2678 Var->getLocation()), 2679 Var->getDeclName(), 2680 IK_Default); 2681 if (!Constructor) 2682 Var->setInvalidDecl(); 2683 else if (!RD->hasTrivialConstructor()) 2684 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2685 } 2686 } 2687 2688#if 0 2689 // FIXME: Temporarily disabled because we are not properly parsing 2690 // linkage specifications on declarations, e.g., 2691 // 2692 // extern "C" const CGPoint CGPointerZero; 2693 // 2694 // C++ [dcl.init]p9: 2695 // 2696 // If no initializer is specified for an object, and the 2697 // object is of (possibly cv-qualified) non-POD class type (or 2698 // array thereof), the object shall be default-initialized; if 2699 // the object is of const-qualified type, the underlying class 2700 // type shall have a user-declared default 2701 // constructor. Otherwise, if no initializer is specified for 2702 // an object, the object and its subobjects, if any, have an 2703 // indeterminate initial value; if the object or any of its 2704 // subobjects are of const-qualified type, the program is 2705 // ill-formed. 2706 // 2707 // This isn't technically an error in C, so we don't diagnose it. 2708 // 2709 // FIXME: Actually perform the POD/user-defined default 2710 // constructor check. 2711 if (getLangOptions().CPlusPlus && 2712 Context.getCanonicalType(Type).isConstQualified() && 2713 !Var->hasExternalStorage()) 2714 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2715 << Var->getName() 2716 << SourceRange(Var->getLocation(), Var->getLocation()); 2717#endif 2718 } 2719} 2720 2721Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2722 unsigned NumDecls) { 2723 llvm::SmallVector<Decl*, 8> Decls; 2724 2725 for (unsigned i = 0; i != NumDecls; ++i) 2726 if (Decl *D = Group[i].getAs<Decl>()) 2727 Decls.push_back(D); 2728 2729 // Perform semantic analysis that depends on having fully processed both 2730 // the declarator and initializer. 2731 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2732 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2733 if (!IDecl) 2734 continue; 2735 QualType T = IDecl->getType(); 2736 2737 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2738 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2739 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2740 if (!IDecl->isInvalidDecl() && 2741 RequireCompleteType(IDecl->getLocation(), T, 2742 diag::err_typecheck_decl_incomplete_type)) 2743 IDecl->setInvalidDecl(); 2744 } 2745 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2746 // object that has file scope without an initializer, and without a 2747 // storage-class specifier or with the storage-class specifier "static", 2748 // constitutes a tentative definition. Note: A tentative definition with 2749 // external linkage is valid (C99 6.2.2p5). 2750 if (IDecl->isTentativeDefinition(Context)) { 2751 QualType CheckType = T; 2752 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2753 2754 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2755 if (ArrayT) { 2756 CheckType = ArrayT->getElementType(); 2757 DiagID = diag::err_illegal_decl_array_incomplete_type; 2758 } 2759 2760 if (IDecl->isInvalidDecl()) { 2761 // Do nothing with invalid declarations 2762 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2763 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2764 // C99 6.9.2p3: If the declaration of an identifier for an object is 2765 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2766 // declared type shall not be an incomplete type. 2767 IDecl->setInvalidDecl(); 2768 } 2769 } 2770 } 2771 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2772 &Decls[0], Decls.size())); 2773} 2774 2775 2776/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2777/// to introduce parameters into function prototype scope. 2778Sema::DeclPtrTy 2779Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2780 const DeclSpec &DS = D.getDeclSpec(); 2781 2782 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2783 VarDecl::StorageClass StorageClass = VarDecl::None; 2784 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2785 StorageClass = VarDecl::Register; 2786 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2787 Diag(DS.getStorageClassSpecLoc(), 2788 diag::err_invalid_storage_class_in_func_decl); 2789 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2790 } 2791 2792 if (D.getDeclSpec().isThreadSpecified()) 2793 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2794 2795 DiagnoseFunctionSpecifiers(D); 2796 2797 // Check that there are no default arguments inside the type of this 2798 // parameter (C++ only). 2799 if (getLangOptions().CPlusPlus) 2800 CheckExtraCXXDefaultArguments(D); 2801 2802 QualType parmDeclType = GetTypeForDeclarator(D, S); 2803 2804 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2805 // Can this happen for params? We already checked that they don't conflict 2806 // among each other. Here they can only shadow globals, which is ok. 2807 IdentifierInfo *II = D.getIdentifier(); 2808 if (II) { 2809 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2810 if (PrevDecl->isTemplateParameter()) { 2811 // Maybe we will complain about the shadowed template parameter. 2812 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2813 // Just pretend that we didn't see the previous declaration. 2814 PrevDecl = 0; 2815 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2816 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2817 2818 // Recover by removing the name 2819 II = 0; 2820 D.SetIdentifier(0, D.getIdentifierLoc()); 2821 } 2822 } 2823 } 2824 2825 // Parameters can not be abstract class types. 2826 // For record types, this is done by the AbstractClassUsageDiagnoser once 2827 // the class has been completely parsed. 2828 if (!CurContext->isRecord() && 2829 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2830 diag::err_abstract_type_in_decl, 2831 AbstractParamType)) 2832 D.setInvalidType(true); 2833 2834 QualType T = adjustParameterType(parmDeclType); 2835 2836 ParmVarDecl *New; 2837 if (T == parmDeclType) // parameter type did not need adjustment 2838 New = ParmVarDecl::Create(Context, CurContext, 2839 D.getIdentifierLoc(), II, 2840 parmDeclType, StorageClass, 2841 0); 2842 else // keep track of both the adjusted and unadjusted types 2843 New = OriginalParmVarDecl::Create(Context, CurContext, 2844 D.getIdentifierLoc(), II, T, 2845 parmDeclType, StorageClass, 0); 2846 2847 if (D.isInvalidType()) 2848 New->setInvalidDecl(); 2849 2850 // Parameter declarators cannot be interface types. All ObjC objects are 2851 // passed by reference. 2852 if (T->isObjCInterfaceType()) { 2853 Diag(D.getIdentifierLoc(), 2854 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2855 New->setInvalidDecl(); 2856 } 2857 2858 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2859 if (D.getCXXScopeSpec().isSet()) { 2860 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2861 << D.getCXXScopeSpec().getRange(); 2862 New->setInvalidDecl(); 2863 } 2864 2865 // Add the parameter declaration into this scope. 2866 S->AddDecl(DeclPtrTy::make(New)); 2867 if (II) 2868 IdResolver.AddDecl(New); 2869 2870 ProcessDeclAttributes(New, D); 2871 2872 if (New->hasAttr<BlocksAttr>()) { 2873 Diag(New->getLocation(), diag::err_block_on_nonlocal); 2874 } 2875 return DeclPtrTy::make(New); 2876} 2877 2878void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2879 SourceLocation LocAfterDecls) { 2880 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2881 "Not a function declarator!"); 2882 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2883 2884 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2885 // for a K&R function. 2886 if (!FTI.hasPrototype) { 2887 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2888 --i; 2889 if (FTI.ArgInfo[i].Param == 0) { 2890 std::string Code = " int "; 2891 Code += FTI.ArgInfo[i].Ident->getName(); 2892 Code += ";\n"; 2893 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2894 << FTI.ArgInfo[i].Ident 2895 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2896 2897 // Implicitly declare the argument as type 'int' for lack of a better 2898 // type. 2899 DeclSpec DS; 2900 const char* PrevSpec; // unused 2901 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2902 PrevSpec); 2903 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2904 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2905 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2906 } 2907 } 2908 } 2909} 2910 2911Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2912 Declarator &D) { 2913 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2914 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2915 "Not a function declarator!"); 2916 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2917 2918 if (FTI.hasPrototype) { 2919 // FIXME: Diagnose arguments without names in C. 2920 } 2921 2922 Scope *ParentScope = FnBodyScope->getParent(); 2923 2924 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2925 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2926} 2927 2928Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2929 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2930 2931 CurFunctionNeedsScopeChecking = false; 2932 2933 // See if this is a redefinition. 2934 const FunctionDecl *Definition; 2935 if (FD->getBody(Context, Definition)) { 2936 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2937 Diag(Definition->getLocation(), diag::note_previous_definition); 2938 } 2939 2940 // Builtin functions cannot be defined. 2941 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2942 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2943 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2944 FD->setInvalidDecl(); 2945 } 2946 } 2947 2948 // The return type of a function definition must be complete 2949 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2950 QualType ResultType = FD->getResultType(); 2951 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2952 !FD->isInvalidDecl() && 2953 RequireCompleteType(FD->getLocation(), ResultType, 2954 diag::err_func_def_incomplete_result)) 2955 FD->setInvalidDecl(); 2956 2957 // GNU warning -Wmissing-prototypes: 2958 // Warn if a global function is defined without a previous 2959 // prototype declaration. This warning is issued even if the 2960 // definition itself provides a prototype. The aim is to detect 2961 // global functions that fail to be declared in header files. 2962 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2963 !FD->isMain()) { 2964 bool MissingPrototype = true; 2965 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2966 Prev; Prev = Prev->getPreviousDeclaration()) { 2967 // Ignore any declarations that occur in function or method 2968 // scope, because they aren't visible from the header. 2969 if (Prev->getDeclContext()->isFunctionOrMethod()) 2970 continue; 2971 2972 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2973 break; 2974 } 2975 2976 if (MissingPrototype) 2977 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2978 } 2979 2980 PushDeclContext(FnBodyScope, FD); 2981 2982 // Check the validity of our function parameters 2983 CheckParmsForFunctionDef(FD); 2984 2985 // Introduce our parameters into the function scope 2986 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2987 ParmVarDecl *Param = FD->getParamDecl(p); 2988 Param->setOwningFunction(FD); 2989 2990 // If this has an identifier, add it to the scope stack. 2991 if (Param->getIdentifier()) 2992 PushOnScopeChains(Param, FnBodyScope); 2993 } 2994 2995 // Checking attributes of current function definition 2996 // dllimport attribute. 2997 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2998 // dllimport attribute cannot be applied to definition. 2999 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3000 Diag(FD->getLocation(), 3001 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3002 << "dllimport"; 3003 FD->setInvalidDecl(); 3004 return DeclPtrTy::make(FD); 3005 } else { 3006 // If a symbol previously declared dllimport is later defined, the 3007 // attribute is ignored in subsequent references, and a warning is 3008 // emitted. 3009 Diag(FD->getLocation(), 3010 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3011 << FD->getNameAsCString() << "dllimport"; 3012 } 3013 } 3014 return DeclPtrTy::make(FD); 3015} 3016 3017 3018Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3019 Decl *dcl = D.getAs<Decl>(); 3020 Stmt *Body = BodyArg.takeAs<Stmt>(); 3021 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3022 FD->setBody(Body); 3023 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3024 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3025 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3026 MD->setBody(Body); 3027 } else { 3028 Body->Destroy(Context); 3029 return DeclPtrTy(); 3030 } 3031 PopDeclContext(); 3032 // Verify and clean out per-function state. 3033 3034 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3035 3036 // Check goto/label use. 3037 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3038 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3039 LabelStmt *L = I->second; 3040 3041 // Verify that we have no forward references left. If so, there was a goto 3042 // or address of a label taken, but no definition of it. Label fwd 3043 // definitions are indicated with a null substmt. 3044 if (L->getSubStmt() != 0) 3045 continue; 3046 3047 // Emit error. 3048 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3049 3050 // At this point, we have gotos that use the bogus label. Stitch it into 3051 // the function body so that they aren't leaked and that the AST is well 3052 // formed. 3053 if (Body == 0) { 3054 // The whole function wasn't parsed correctly, just delete this. 3055 L->Destroy(Context); 3056 continue; 3057 } 3058 3059 // Otherwise, the body is valid: we want to stitch the label decl into the 3060 // function somewhere so that it is properly owned and so that the goto 3061 // has a valid target. Do this by creating a new compound stmt with the 3062 // label in it. 3063 3064 // Give the label a sub-statement. 3065 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3066 3067 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3068 cast<CXXTryStmt>(Body)->getTryBlock() : 3069 cast<CompoundStmt>(Body); 3070 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3071 Elements.push_back(L); 3072 Compound->setStmts(Context, &Elements[0], Elements.size()); 3073 } 3074 FunctionLabelMap.clear(); 3075 3076 if (!Body) return D; 3077 3078 // Verify that that gotos and switch cases don't jump into scopes illegally. 3079 if (CurFunctionNeedsScopeChecking) 3080 DiagnoseInvalidJumps(Body); 3081 3082 // C++ constructors that have function-try-blocks can't have return statements 3083 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3084 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3085 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3086 3087 return D; 3088} 3089 3090/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3091/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3092NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3093 IdentifierInfo &II, Scope *S) { 3094 // Before we produce a declaration for an implicitly defined 3095 // function, see whether there was a locally-scoped declaration of 3096 // this name as a function or variable. If so, use that 3097 // (non-visible) declaration, and complain about it. 3098 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3099 = LocallyScopedExternalDecls.find(&II); 3100 if (Pos != LocallyScopedExternalDecls.end()) { 3101 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3102 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3103 return Pos->second; 3104 } 3105 3106 // Extension in C99. Legal in C90, but warn about it. 3107 if (getLangOptions().C99) 3108 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3109 else 3110 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3111 3112 // FIXME: handle stuff like: 3113 // void foo() { extern float X(); } 3114 // void bar() { X(); } <-- implicit decl for X in another scope. 3115 3116 // Set a Declarator for the implicit definition: int foo(); 3117 const char *Dummy; 3118 DeclSpec DS; 3119 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3120 Error = Error; // Silence warning. 3121 assert(!Error && "Error setting up implicit decl!"); 3122 Declarator D(DS, Declarator::BlockContext); 3123 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3124 0, 0, false, false, 0, 0, Loc, D), 3125 SourceLocation()); 3126 D.SetIdentifier(&II, Loc); 3127 3128 // Insert this function into translation-unit scope. 3129 3130 DeclContext *PrevDC = CurContext; 3131 CurContext = Context.getTranslationUnitDecl(); 3132 3133 FunctionDecl *FD = 3134 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3135 FD->setImplicit(); 3136 3137 CurContext = PrevDC; 3138 3139 AddKnownFunctionAttributes(FD); 3140 3141 return FD; 3142} 3143 3144/// \brief Adds any function attributes that we know a priori based on 3145/// the declaration of this function. 3146/// 3147/// These attributes can apply both to implicitly-declared builtins 3148/// (like __builtin___printf_chk) or to library-declared functions 3149/// like NSLog or printf. 3150void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3151 if (FD->isInvalidDecl()) 3152 return; 3153 3154 // If this is a built-in function, map its builtin attributes to 3155 // actual attributes. 3156 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3157 // Handle printf-formatting attributes. 3158 unsigned FormatIdx; 3159 bool HasVAListArg; 3160 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3161 if (!FD->getAttr<FormatAttr>()) 3162 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3163 FormatIdx + 2)); 3164 } 3165 3166 // Mark const if we don't care about errno and that is the only 3167 // thing preventing the function from being const. This allows 3168 // IRgen to use LLVM intrinsics for such functions. 3169 if (!getLangOptions().MathErrno && 3170 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3171 if (!FD->getAttr<ConstAttr>()) 3172 FD->addAttr(::new (Context) ConstAttr()); 3173 } 3174 } 3175 3176 IdentifierInfo *Name = FD->getIdentifier(); 3177 if (!Name) 3178 return; 3179 if ((!getLangOptions().CPlusPlus && 3180 FD->getDeclContext()->isTranslationUnit()) || 3181 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3182 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3183 LinkageSpecDecl::lang_c)) { 3184 // Okay: this could be a libc/libm/Objective-C function we know 3185 // about. 3186 } else 3187 return; 3188 3189 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3190 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3191 // FIXME: We known better than our headers. 3192 const_cast<FormatAttr *>(Format)->setType("printf"); 3193 } else 3194 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3195 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3196 if (!FD->getAttr<FormatAttr>()) 3197 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3198 } 3199} 3200 3201TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3202 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3203 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3204 3205 // Scope manipulation handled by caller. 3206 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3207 D.getIdentifierLoc(), 3208 D.getIdentifier(), 3209 T); 3210 3211 if (TagType *TT = dyn_cast<TagType>(T)) { 3212 TagDecl *TD = TT->getDecl(); 3213 3214 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3215 // keep track of the TypedefDecl. 3216 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3217 TD->setTypedefForAnonDecl(NewTD); 3218 } 3219 3220 if (D.isInvalidType()) 3221 NewTD->setInvalidDecl(); 3222 return NewTD; 3223} 3224 3225/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3226/// former case, Name will be non-null. In the later case, Name will be null. 3227/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3228/// reference/declaration/definition of a tag. 3229Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3230 SourceLocation KWLoc, const CXXScopeSpec &SS, 3231 IdentifierInfo *Name, SourceLocation NameLoc, 3232 AttributeList *Attr, AccessSpecifier AS) { 3233 // If this is not a definition, it must have a name. 3234 assert((Name != 0 || TK == TK_Definition) && 3235 "Nameless record must be a definition!"); 3236 3237 TagDecl::TagKind Kind; 3238 switch (TagSpec) { 3239 default: assert(0 && "Unknown tag type!"); 3240 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3241 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3242 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3243 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3244 } 3245 3246 DeclContext *SearchDC = CurContext; 3247 DeclContext *DC = CurContext; 3248 NamedDecl *PrevDecl = 0; 3249 3250 bool Invalid = false; 3251 3252 if (Name && SS.isNotEmpty()) { 3253 // We have a nested-name tag ('struct foo::bar'). 3254 3255 // Check for invalid 'foo::'. 3256 if (SS.isInvalid()) { 3257 Name = 0; 3258 goto CreateNewDecl; 3259 } 3260 3261 // FIXME: RequireCompleteDeclContext(SS)? 3262 DC = computeDeclContext(SS); 3263 SearchDC = DC; 3264 // Look-up name inside 'foo::'. 3265 PrevDecl = dyn_cast_or_null<TagDecl>( 3266 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3267 3268 // A tag 'foo::bar' must already exist. 3269 if (PrevDecl == 0) { 3270 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3271 Name = 0; 3272 goto CreateNewDecl; 3273 } 3274 } else if (Name) { 3275 // If this is a named struct, check to see if there was a previous forward 3276 // declaration or definition. 3277 // FIXME: We're looking into outer scopes here, even when we 3278 // shouldn't be. Doing so can result in ambiguities that we 3279 // shouldn't be diagnosing. 3280 LookupResult R = LookupName(S, Name, LookupTagName, 3281 /*RedeclarationOnly=*/(TK != TK_Reference)); 3282 if (R.isAmbiguous()) { 3283 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3284 // FIXME: This is not best way to recover from case like: 3285 // 3286 // struct S s; 3287 // 3288 // causes needless "incomplete type" error later. 3289 Name = 0; 3290 PrevDecl = 0; 3291 Invalid = true; 3292 } 3293 else 3294 PrevDecl = R; 3295 3296 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3297 // FIXME: This makes sure that we ignore the contexts associated 3298 // with C structs, unions, and enums when looking for a matching 3299 // tag declaration or definition. See the similar lookup tweak 3300 // in Sema::LookupName; is there a better way to deal with this? 3301 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3302 SearchDC = SearchDC->getParent(); 3303 } 3304 } 3305 3306 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3307 // Maybe we will complain about the shadowed template parameter. 3308 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3309 // Just pretend that we didn't see the previous declaration. 3310 PrevDecl = 0; 3311 } 3312 3313 if (PrevDecl) { 3314 // Check whether the previous declaration is usable. 3315 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3316 3317 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3318 // If this is a use of a previous tag, or if the tag is already declared 3319 // in the same scope (so that the definition/declaration completes or 3320 // rementions the tag), reuse the decl. 3321 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3322 // Make sure that this wasn't declared as an enum and now used as a 3323 // struct or something similar. 3324 if (!isAcceptableTagRedeclaration(PrevTagDecl->getTagKind(), Kind)) { 3325 bool SafeToContinue 3326 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3327 Kind != TagDecl::TK_enum); 3328 if (SafeToContinue) 3329 Diag(KWLoc, diag::err_use_with_wrong_tag) 3330 << Name 3331 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3332 PrevTagDecl->getKindName()); 3333 else 3334 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3335 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3336 3337 if (SafeToContinue) 3338 Kind = PrevTagDecl->getTagKind(); 3339 else { 3340 // Recover by making this an anonymous redefinition. 3341 Name = 0; 3342 PrevDecl = 0; 3343 Invalid = true; 3344 } 3345 } 3346 3347 if (!Invalid) { 3348 // If this is a use, just return the declaration we found. 3349 3350 // FIXME: In the future, return a variant or some other clue 3351 // for the consumer of this Decl to know it doesn't own it. 3352 // For our current ASTs this shouldn't be a problem, but will 3353 // need to be changed with DeclGroups. 3354 if (TK == TK_Reference) 3355 return DeclPtrTy::make(PrevDecl); 3356 3357 // Diagnose attempts to redefine a tag. 3358 if (TK == TK_Definition) { 3359 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3360 Diag(NameLoc, diag::err_redefinition) << Name; 3361 Diag(Def->getLocation(), diag::note_previous_definition); 3362 // If this is a redefinition, recover by making this 3363 // struct be anonymous, which will make any later 3364 // references get the previous definition. 3365 Name = 0; 3366 PrevDecl = 0; 3367 Invalid = true; 3368 } else { 3369 // If the type is currently being defined, complain 3370 // about a nested redefinition. 3371 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3372 if (Tag->isBeingDefined()) { 3373 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3374 Diag(PrevTagDecl->getLocation(), 3375 diag::note_previous_definition); 3376 Name = 0; 3377 PrevDecl = 0; 3378 Invalid = true; 3379 } 3380 } 3381 3382 // Okay, this is definition of a previously declared or referenced 3383 // tag PrevDecl. We're going to create a new Decl for it. 3384 } 3385 } 3386 // If we get here we have (another) forward declaration or we 3387 // have a definition. Just create a new decl. 3388 } else { 3389 // If we get here, this is a definition of a new tag type in a nested 3390 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3391 // new decl/type. We set PrevDecl to NULL so that the entities 3392 // have distinct types. 3393 PrevDecl = 0; 3394 } 3395 // If we get here, we're going to create a new Decl. If PrevDecl 3396 // is non-NULL, it's a definition of the tag declared by 3397 // PrevDecl. If it's NULL, we have a new definition. 3398 } else { 3399 // PrevDecl is a namespace, template, or anything else 3400 // that lives in the IDNS_Tag identifier namespace. 3401 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3402 // The tag name clashes with a namespace name, issue an error and 3403 // recover by making this tag be anonymous. 3404 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3405 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3406 Name = 0; 3407 PrevDecl = 0; 3408 Invalid = true; 3409 } else { 3410 // The existing declaration isn't relevant to us; we're in a 3411 // new scope, so clear out the previous declaration. 3412 PrevDecl = 0; 3413 } 3414 } 3415 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3416 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3417 // C++ [basic.scope.pdecl]p5: 3418 // -- for an elaborated-type-specifier of the form 3419 // 3420 // class-key identifier 3421 // 3422 // if the elaborated-type-specifier is used in the 3423 // decl-specifier-seq or parameter-declaration-clause of a 3424 // function defined in namespace scope, the identifier is 3425 // declared as a class-name in the namespace that contains 3426 // the declaration; otherwise, except as a friend 3427 // declaration, the identifier is declared in the smallest 3428 // non-class, non-function-prototype scope that contains the 3429 // declaration. 3430 // 3431 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3432 // C structs and unions. 3433 // 3434 // GNU C also supports this behavior as part of its incomplete 3435 // enum types extension, while GNU C++ does not. 3436 // 3437 // Find the context where we'll be declaring the tag. 3438 // FIXME: We would like to maintain the current DeclContext as the 3439 // lexical context, 3440 while (SearchDC->isRecord()) 3441 SearchDC = SearchDC->getParent(); 3442 3443 // Find the scope where we'll be declaring the tag. 3444 while (S->isClassScope() || 3445 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3446 ((S->getFlags() & Scope::DeclScope) == 0) || 3447 (S->getEntity() && 3448 ((DeclContext *)S->getEntity())->isTransparentContext())) 3449 S = S->getParent(); 3450 } 3451 3452CreateNewDecl: 3453 3454 // If there is an identifier, use the location of the identifier as the 3455 // location of the decl, otherwise use the location of the struct/union 3456 // keyword. 3457 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3458 3459 // Otherwise, create a new declaration. If there is a previous 3460 // declaration of the same entity, the two will be linked via 3461 // PrevDecl. 3462 TagDecl *New; 3463 3464 if (Kind == TagDecl::TK_enum) { 3465 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3466 // enum X { A, B, C } D; D should chain to X. 3467 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3468 cast_or_null<EnumDecl>(PrevDecl)); 3469 // If this is an undefined enum, warn. 3470 if (TK != TK_Definition && !Invalid) { 3471 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3472 : diag::ext_forward_ref_enum; 3473 Diag(Loc, DK); 3474 } 3475 } else { 3476 // struct/union/class 3477 3478 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3479 // struct X { int A; } D; D should chain to X. 3480 if (getLangOptions().CPlusPlus) 3481 // FIXME: Look for a way to use RecordDecl for simple structs. 3482 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3483 cast_or_null<CXXRecordDecl>(PrevDecl)); 3484 else 3485 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3486 cast_or_null<RecordDecl>(PrevDecl)); 3487 } 3488 3489 if (Kind != TagDecl::TK_enum) { 3490 // Handle #pragma pack: if the #pragma pack stack has non-default 3491 // alignment, make up a packed attribute for this decl. These 3492 // attributes are checked when the ASTContext lays out the 3493 // structure. 3494 // 3495 // It is important for implementing the correct semantics that this 3496 // happen here (in act on tag decl). The #pragma pack stack is 3497 // maintained as a result of parser callbacks which can occur at 3498 // many points during the parsing of a struct declaration (because 3499 // the #pragma tokens are effectively skipped over during the 3500 // parsing of the struct). 3501 if (unsigned Alignment = getPragmaPackAlignment()) 3502 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3503 } 3504 3505 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3506 // C++ [dcl.typedef]p3: 3507 // [...] Similarly, in a given scope, a class or enumeration 3508 // shall not be declared with the same name as a typedef-name 3509 // that is declared in that scope and refers to a type other 3510 // than the class or enumeration itself. 3511 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3512 TypedefDecl *PrevTypedef = 0; 3513 if (Lookup.getKind() == LookupResult::Found) 3514 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3515 3516 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3517 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3518 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3519 Diag(Loc, diag::err_tag_definition_of_typedef) 3520 << Context.getTypeDeclType(New) 3521 << PrevTypedef->getUnderlyingType(); 3522 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3523 Invalid = true; 3524 } 3525 } 3526 3527 if (Invalid) 3528 New->setInvalidDecl(); 3529 3530 if (Attr) 3531 ProcessDeclAttributeList(New, Attr); 3532 3533 // If we're declaring or defining a tag in function prototype scope 3534 // in C, note that this type can only be used within the function. 3535 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3536 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3537 3538 // Set the lexical context. If the tag has a C++ scope specifier, the 3539 // lexical context will be different from the semantic context. 3540 New->setLexicalDeclContext(CurContext); 3541 3542 // Set the access specifier. 3543 SetMemberAccessSpecifier(New, PrevDecl, AS); 3544 3545 if (TK == TK_Definition) 3546 New->startDefinition(); 3547 3548 // If this has an identifier, add it to the scope stack. 3549 if (Name) { 3550 S = getNonFieldDeclScope(S); 3551 PushOnScopeChains(New, S); 3552 } else { 3553 CurContext->addDecl(Context, New); 3554 } 3555 3556 return DeclPtrTy::make(New); 3557} 3558 3559void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3560 AdjustDeclIfTemplate(TagD); 3561 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3562 3563 // Enter the tag context. 3564 PushDeclContext(S, Tag); 3565 3566 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3567 FieldCollector->StartClass(); 3568 3569 if (Record->getIdentifier()) { 3570 // C++ [class]p2: 3571 // [...] The class-name is also inserted into the scope of the 3572 // class itself; this is known as the injected-class-name. For 3573 // purposes of access checking, the injected-class-name is treated 3574 // as if it were a public member name. 3575 CXXRecordDecl *InjectedClassName 3576 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3577 CurContext, Record->getLocation(), 3578 Record->getIdentifier(), Record); 3579 InjectedClassName->setImplicit(); 3580 InjectedClassName->setAccess(AS_public); 3581 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3582 InjectedClassName->setDescribedClassTemplate(Template); 3583 PushOnScopeChains(InjectedClassName, S); 3584 assert(InjectedClassName->isInjectedClassName() && 3585 "Broken injected-class-name"); 3586 } 3587 } 3588} 3589 3590void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3591 AdjustDeclIfTemplate(TagD); 3592 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3593 3594 if (isa<CXXRecordDecl>(Tag)) 3595 FieldCollector->FinishClass(); 3596 3597 // Exit this scope of this tag's definition. 3598 PopDeclContext(); 3599 3600 // Notify the consumer that we've defined a tag. 3601 Consumer.HandleTagDeclDefinition(Tag); 3602} 3603 3604// Note that FieldName may be null for anonymous bitfields. 3605bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3606 QualType FieldTy, const Expr *BitWidth) { 3607 3608 // C99 6.7.2.1p4 - verify the field type. 3609 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3610 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3611 // Handle incomplete types with specific error. 3612 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3613 return true; 3614 if (FieldName) 3615 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3616 << FieldName << FieldTy << BitWidth->getSourceRange(); 3617 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3618 << FieldTy << BitWidth->getSourceRange(); 3619 } 3620 3621 // If the bit-width is type- or value-dependent, don't try to check 3622 // it now. 3623 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3624 return false; 3625 3626 llvm::APSInt Value; 3627 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3628 return true; 3629 3630 // Zero-width bitfield is ok for anonymous field. 3631 if (Value == 0 && FieldName) 3632 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3633 3634 if (Value.isSigned() && Value.isNegative()) { 3635 if (FieldName) 3636 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3637 << FieldName << Value.toString(10); 3638 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3639 << Value.toString(10); 3640 } 3641 3642 if (!FieldTy->isDependentType()) { 3643 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3644 if (Value.getZExtValue() > TypeSize) { 3645 if (FieldName) 3646 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3647 << FieldName << (unsigned)TypeSize; 3648 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3649 << (unsigned)TypeSize; 3650 } 3651 } 3652 3653 return false; 3654} 3655 3656/// ActOnField - Each field of a struct/union/class is passed into this in order 3657/// to create a FieldDecl object for it. 3658Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3659 SourceLocation DeclStart, 3660 Declarator &D, ExprTy *BitfieldWidth) { 3661 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3662 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3663 AS_public); 3664 return DeclPtrTy::make(Res); 3665} 3666 3667/// HandleField - Analyze a field of a C struct or a C++ data member. 3668/// 3669FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3670 SourceLocation DeclStart, 3671 Declarator &D, Expr *BitWidth, 3672 AccessSpecifier AS) { 3673 IdentifierInfo *II = D.getIdentifier(); 3674 SourceLocation Loc = DeclStart; 3675 if (II) Loc = D.getIdentifierLoc(); 3676 3677 QualType T = GetTypeForDeclarator(D, S); 3678 if (getLangOptions().CPlusPlus) 3679 CheckExtraCXXDefaultArguments(D); 3680 3681 DiagnoseFunctionSpecifiers(D); 3682 3683 if (D.getDeclSpec().isThreadSpecified()) 3684 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3685 3686 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3687 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3688 PrevDecl = 0; 3689 3690 FieldDecl *NewFD 3691 = CheckFieldDecl(II, T, Record, Loc, 3692 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3693 BitWidth, AS, PrevDecl, &D); 3694 if (NewFD->isInvalidDecl() && PrevDecl) { 3695 // Don't introduce NewFD into scope; there's already something 3696 // with the same name in the same scope. 3697 } else if (II) { 3698 PushOnScopeChains(NewFD, S); 3699 } else 3700 Record->addDecl(Context, NewFD); 3701 3702 return NewFD; 3703} 3704 3705/// \brief Build a new FieldDecl and check its well-formedness. 3706/// 3707/// This routine builds a new FieldDecl given the fields name, type, 3708/// record, etc. \p PrevDecl should refer to any previous declaration 3709/// with the same name and in the same scope as the field to be 3710/// created. 3711/// 3712/// \returns a new FieldDecl. 3713/// 3714/// \todo The Declarator argument is a hack. It will be removed once 3715FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3716 RecordDecl *Record, SourceLocation Loc, 3717 bool Mutable, Expr *BitWidth, 3718 AccessSpecifier AS, NamedDecl *PrevDecl, 3719 Declarator *D) { 3720 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3721 bool InvalidDecl = false; 3722 if (D) InvalidDecl = D->isInvalidType(); 3723 3724 // If we receive a broken type, recover by assuming 'int' and 3725 // marking this declaration as invalid. 3726 if (T.isNull()) { 3727 InvalidDecl = true; 3728 T = Context.IntTy; 3729 } 3730 3731 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3732 // than a variably modified type. 3733 if (T->isVariablyModifiedType()) { 3734 bool SizeIsNegative; 3735 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3736 SizeIsNegative); 3737 if (!FixedTy.isNull()) { 3738 Diag(Loc, diag::warn_illegal_constant_array_size); 3739 T = FixedTy; 3740 } else { 3741 if (SizeIsNegative) 3742 Diag(Loc, diag::err_typecheck_negative_array_size); 3743 else 3744 Diag(Loc, diag::err_typecheck_field_variable_size); 3745 T = Context.IntTy; 3746 InvalidDecl = true; 3747 } 3748 } 3749 3750 // Fields can not have abstract class types 3751 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3752 AbstractFieldType)) 3753 InvalidDecl = true; 3754 3755 // If this is declared as a bit-field, check the bit-field. 3756 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3757 InvalidDecl = true; 3758 DeleteExpr(BitWidth); 3759 BitWidth = 0; 3760 } 3761 3762 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3763 Mutable); 3764 if (InvalidDecl) 3765 NewFD->setInvalidDecl(); 3766 3767 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3768 Diag(Loc, diag::err_duplicate_member) << II; 3769 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3770 NewFD->setInvalidDecl(); 3771 } 3772 3773 if (getLangOptions().CPlusPlus && !T->isPODType()) 3774 cast<CXXRecordDecl>(Record)->setPOD(false); 3775 3776 // FIXME: We need to pass in the attributes given an AST 3777 // representation, not a parser representation. 3778 if (D) 3779 ProcessDeclAttributes(NewFD, *D); 3780 3781 if (T.isObjCGCWeak()) 3782 Diag(Loc, diag::warn_attribute_weak_on_field); 3783 3784 NewFD->setAccess(AS); 3785 3786 // C++ [dcl.init.aggr]p1: 3787 // An aggregate is an array or a class (clause 9) with [...] no 3788 // private or protected non-static data members (clause 11). 3789 // A POD must be an aggregate. 3790 if (getLangOptions().CPlusPlus && 3791 (AS == AS_private || AS == AS_protected)) { 3792 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3793 CXXRecord->setAggregate(false); 3794 CXXRecord->setPOD(false); 3795 } 3796 3797 return NewFD; 3798} 3799 3800/// TranslateIvarVisibility - Translate visibility from a token ID to an 3801/// AST enum value. 3802static ObjCIvarDecl::AccessControl 3803TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3804 switch (ivarVisibility) { 3805 default: assert(0 && "Unknown visitibility kind"); 3806 case tok::objc_private: return ObjCIvarDecl::Private; 3807 case tok::objc_public: return ObjCIvarDecl::Public; 3808 case tok::objc_protected: return ObjCIvarDecl::Protected; 3809 case tok::objc_package: return ObjCIvarDecl::Package; 3810 } 3811} 3812 3813/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3814/// in order to create an IvarDecl object for it. 3815Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3816 SourceLocation DeclStart, 3817 Declarator &D, ExprTy *BitfieldWidth, 3818 tok::ObjCKeywordKind Visibility) { 3819 3820 IdentifierInfo *II = D.getIdentifier(); 3821 Expr *BitWidth = (Expr*)BitfieldWidth; 3822 SourceLocation Loc = DeclStart; 3823 if (II) Loc = D.getIdentifierLoc(); 3824 3825 // FIXME: Unnamed fields can be handled in various different ways, for 3826 // example, unnamed unions inject all members into the struct namespace! 3827 3828 QualType T = GetTypeForDeclarator(D, S); 3829 3830 if (BitWidth) { 3831 // 6.7.2.1p3, 6.7.2.1p4 3832 if (VerifyBitField(Loc, II, T, BitWidth)) { 3833 D.setInvalidType(); 3834 DeleteExpr(BitWidth); 3835 BitWidth = 0; 3836 } 3837 } else { 3838 // Not a bitfield. 3839 3840 // validate II. 3841 3842 } 3843 3844 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3845 // than a variably modified type. 3846 if (T->isVariablyModifiedType()) { 3847 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3848 D.setInvalidType(); 3849 } 3850 3851 // Get the visibility (access control) for this ivar. 3852 ObjCIvarDecl::AccessControl ac = 3853 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3854 : ObjCIvarDecl::None; 3855 3856 // Construct the decl. 3857 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3858 (Expr *)BitfieldWidth); 3859 3860 if (II) { 3861 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3862 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3863 && !isa<TagDecl>(PrevDecl)) { 3864 Diag(Loc, diag::err_duplicate_member) << II; 3865 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3866 NewID->setInvalidDecl(); 3867 } 3868 } 3869 3870 // Process attributes attached to the ivar. 3871 ProcessDeclAttributes(NewID, D); 3872 3873 if (D.isInvalidType()) 3874 NewID->setInvalidDecl(); 3875 3876 if (II) { 3877 // FIXME: When interfaces are DeclContexts, we'll need to add 3878 // these to the interface. 3879 S->AddDecl(DeclPtrTy::make(NewID)); 3880 IdResolver.AddDecl(NewID); 3881 } 3882 3883 return DeclPtrTy::make(NewID); 3884} 3885 3886void Sema::ActOnFields(Scope* S, 3887 SourceLocation RecLoc, DeclPtrTy RecDecl, 3888 DeclPtrTy *Fields, unsigned NumFields, 3889 SourceLocation LBrac, SourceLocation RBrac, 3890 AttributeList *Attr) { 3891 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3892 assert(EnclosingDecl && "missing record or interface decl"); 3893 3894 // If the decl this is being inserted into is invalid, then it may be a 3895 // redeclaration or some other bogus case. Don't try to add fields to it. 3896 if (EnclosingDecl->isInvalidDecl()) { 3897 // FIXME: Deallocate fields? 3898 return; 3899 } 3900 3901 3902 // Verify that all the fields are okay. 3903 unsigned NumNamedMembers = 0; 3904 llvm::SmallVector<FieldDecl*, 32> RecFields; 3905 3906 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3907 for (unsigned i = 0; i != NumFields; ++i) { 3908 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3909 3910 // Get the type for the field. 3911 Type *FDTy = FD->getType().getTypePtr(); 3912 3913 if (!FD->isAnonymousStructOrUnion()) { 3914 // Remember all fields written by the user. 3915 RecFields.push_back(FD); 3916 } 3917 3918 // If the field is already invalid for some reason, don't emit more 3919 // diagnostics about it. 3920 if (FD->isInvalidDecl()) 3921 continue; 3922 3923 // C99 6.7.2.1p2: 3924 // A structure or union shall not contain a member with 3925 // incomplete or function type (hence, a structure shall not 3926 // contain an instance of itself, but may contain a pointer to 3927 // an instance of itself), except that the last member of a 3928 // structure with more than one named member may have incomplete 3929 // array type; such a structure (and any union containing, 3930 // possibly recursively, a member that is such a structure) 3931 // shall not be a member of a structure or an element of an 3932 // array. 3933 if (FDTy->isFunctionType()) { 3934 // Field declared as a function. 3935 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3936 << FD->getDeclName(); 3937 FD->setInvalidDecl(); 3938 EnclosingDecl->setInvalidDecl(); 3939 continue; 3940 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3941 Record && Record->isStruct()) { 3942 // Flexible array member. 3943 if (NumNamedMembers < 1) { 3944 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3945 << FD->getDeclName(); 3946 FD->setInvalidDecl(); 3947 EnclosingDecl->setInvalidDecl(); 3948 continue; 3949 } 3950 // Okay, we have a legal flexible array member at the end of the struct. 3951 if (Record) 3952 Record->setHasFlexibleArrayMember(true); 3953 } else if (!FDTy->isDependentType() && 3954 RequireCompleteType(FD->getLocation(), FD->getType(), 3955 diag::err_field_incomplete)) { 3956 // Incomplete type 3957 FD->setInvalidDecl(); 3958 EnclosingDecl->setInvalidDecl(); 3959 continue; 3960 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3961 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3962 // If this is a member of a union, then entire union becomes "flexible". 3963 if (Record && Record->isUnion()) { 3964 Record->setHasFlexibleArrayMember(true); 3965 } else { 3966 // If this is a struct/class and this is not the last element, reject 3967 // it. Note that GCC supports variable sized arrays in the middle of 3968 // structures. 3969 if (i != NumFields-1) 3970 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3971 << FD->getDeclName() << FD->getType(); 3972 else { 3973 // We support flexible arrays at the end of structs in 3974 // other structs as an extension. 3975 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3976 << FD->getDeclName(); 3977 if (Record) 3978 Record->setHasFlexibleArrayMember(true); 3979 } 3980 } 3981 } 3982 } else if (FDTy->isObjCInterfaceType()) { 3983 /// A field cannot be an Objective-c object 3984 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3985 FD->setInvalidDecl(); 3986 EnclosingDecl->setInvalidDecl(); 3987 continue; 3988 } 3989 // Keep track of the number of named members. 3990 if (FD->getIdentifier()) 3991 ++NumNamedMembers; 3992 } 3993 3994 // Okay, we successfully defined 'Record'. 3995 if (Record) { 3996 Record->completeDefinition(Context); 3997 } else { 3998 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3999 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4000 ID->setIVarList(ClsFields, RecFields.size(), Context); 4001 ID->setLocEnd(RBrac); 4002 4003 // Must enforce the rule that ivars in the base classes may not be 4004 // duplicates. 4005 if (ID->getSuperClass()) { 4006 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4007 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4008 ObjCIvarDecl* Ivar = (*IVI); 4009 4010 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4011 ObjCIvarDecl* prevIvar = 4012 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4013 if (prevIvar) { 4014 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4015 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4016 } 4017 } 4018 } 4019 } 4020 } else if (ObjCImplementationDecl *IMPDecl = 4021 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4022 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4023 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 4024 // FIXME: Set the DeclContext correctly when we build the 4025 // declarations. 4026 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4027 IMPDecl->addDecl(Context, ClsFields[I]); 4028 } 4029 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4030 } 4031 } 4032 4033 if (Attr) 4034 ProcessDeclAttributeList(Record, Attr); 4035} 4036 4037EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4038 EnumConstantDecl *LastEnumConst, 4039 SourceLocation IdLoc, 4040 IdentifierInfo *Id, 4041 ExprArg val) { 4042 Expr *Val = (Expr *)val.get(); 4043 4044 llvm::APSInt EnumVal(32); 4045 QualType EltTy; 4046 if (Val && !Val->isTypeDependent()) { 4047 // Make sure to promote the operand type to int. 4048 UsualUnaryConversions(Val); 4049 if (Val != val.get()) { 4050 val.release(); 4051 val = Val; 4052 } 4053 4054 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4055 SourceLocation ExpLoc; 4056 if (!Val->isValueDependent() && 4057 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4058 Val = 0; 4059 } else { 4060 EltTy = Val->getType(); 4061 } 4062 } 4063 4064 if (!Val) { 4065 if (LastEnumConst) { 4066 // Assign the last value + 1. 4067 EnumVal = LastEnumConst->getInitVal(); 4068 ++EnumVal; 4069 4070 // Check for overflow on increment. 4071 if (EnumVal < LastEnumConst->getInitVal()) 4072 Diag(IdLoc, diag::warn_enum_value_overflow); 4073 4074 EltTy = LastEnumConst->getType(); 4075 } else { 4076 // First value, set to zero. 4077 EltTy = Context.IntTy; 4078 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4079 } 4080 } 4081 4082 val.release(); 4083 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4084 Val, EnumVal); 4085} 4086 4087 4088Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4089 DeclPtrTy lastEnumConst, 4090 SourceLocation IdLoc, 4091 IdentifierInfo *Id, 4092 SourceLocation EqualLoc, ExprTy *val) { 4093 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4094 EnumConstantDecl *LastEnumConst = 4095 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4096 Expr *Val = static_cast<Expr*>(val); 4097 4098 // The scope passed in may not be a decl scope. Zip up the scope tree until 4099 // we find one that is. 4100 S = getNonFieldDeclScope(S); 4101 4102 // Verify that there isn't already something declared with this name in this 4103 // scope. 4104 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4105 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4106 // Maybe we will complain about the shadowed template parameter. 4107 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4108 // Just pretend that we didn't see the previous declaration. 4109 PrevDecl = 0; 4110 } 4111 4112 if (PrevDecl) { 4113 // When in C++, we may get a TagDecl with the same name; in this case the 4114 // enum constant will 'hide' the tag. 4115 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4116 "Received TagDecl when not in C++!"); 4117 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4118 if (isa<EnumConstantDecl>(PrevDecl)) 4119 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4120 else 4121 Diag(IdLoc, diag::err_redefinition) << Id; 4122 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4123 if (Val) Val->Destroy(Context); 4124 return DeclPtrTy(); 4125 } 4126 } 4127 4128 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4129 IdLoc, Id, Owned(Val)); 4130 4131 // Register this decl in the current scope stack. 4132 if (New) 4133 PushOnScopeChains(New, S); 4134 4135 return DeclPtrTy::make(New); 4136} 4137 4138// FIXME: For consistency with ActOnFields(), we should have the parser 4139// pass in the source location for the left/right braces. 4140void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4141 DeclPtrTy *Elements, unsigned NumElements) { 4142 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4143 QualType EnumType = Context.getTypeDeclType(Enum); 4144 4145 // TODO: If the result value doesn't fit in an int, it must be a long or long 4146 // long value. ISO C does not support this, but GCC does as an extension, 4147 // emit a warning. 4148 unsigned IntWidth = Context.Target.getIntWidth(); 4149 4150 // Verify that all the values are okay, compute the size of the values, and 4151 // reverse the list. 4152 unsigned NumNegativeBits = 0; 4153 unsigned NumPositiveBits = 0; 4154 4155 // Keep track of whether all elements have type int. 4156 bool AllElementsInt = true; 4157 4158 for (unsigned i = 0; i != NumElements; ++i) { 4159 EnumConstantDecl *ECD = 4160 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4161 if (!ECD) continue; // Already issued a diagnostic. 4162 4163 // If the enum value doesn't fit in an int, emit an extension warning. 4164 const llvm::APSInt &InitVal = ECD->getInitVal(); 4165 assert(InitVal.getBitWidth() >= IntWidth && 4166 "Should have promoted value to int"); 4167 if (InitVal.getBitWidth() > IntWidth) { 4168 llvm::APSInt V(InitVal); 4169 V.trunc(IntWidth); 4170 V.extend(InitVal.getBitWidth()); 4171 if (V != InitVal) 4172 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4173 << InitVal.toString(10); 4174 } 4175 4176 // Keep track of the size of positive and negative values. 4177 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4178 NumPositiveBits = std::max(NumPositiveBits, 4179 (unsigned)InitVal.getActiveBits()); 4180 else 4181 NumNegativeBits = std::max(NumNegativeBits, 4182 (unsigned)InitVal.getMinSignedBits()); 4183 4184 // Keep track of whether every enum element has type int (very commmon). 4185 if (AllElementsInt) 4186 AllElementsInt = ECD->getType() == Context.IntTy; 4187 } 4188 4189 // Figure out the type that should be used for this enum. 4190 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4191 QualType BestType; 4192 unsigned BestWidth; 4193 4194 if (NumNegativeBits) { 4195 // If there is a negative value, figure out the smallest integer type (of 4196 // int/long/longlong) that fits. 4197 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4198 BestType = Context.IntTy; 4199 BestWidth = IntWidth; 4200 } else { 4201 BestWidth = Context.Target.getLongWidth(); 4202 4203 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4204 BestType = Context.LongTy; 4205 else { 4206 BestWidth = Context.Target.getLongLongWidth(); 4207 4208 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4209 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4210 BestType = Context.LongLongTy; 4211 } 4212 } 4213 } else { 4214 // If there is no negative value, figure out which of uint, ulong, ulonglong 4215 // fits. 4216 if (NumPositiveBits <= IntWidth) { 4217 BestType = Context.UnsignedIntTy; 4218 BestWidth = IntWidth; 4219 } else if (NumPositiveBits <= 4220 (BestWidth = Context.Target.getLongWidth())) { 4221 BestType = Context.UnsignedLongTy; 4222 } else { 4223 BestWidth = Context.Target.getLongLongWidth(); 4224 assert(NumPositiveBits <= BestWidth && 4225 "How could an initializer get larger than ULL?"); 4226 BestType = Context.UnsignedLongLongTy; 4227 } 4228 } 4229 4230 // Loop over all of the enumerator constants, changing their types to match 4231 // the type of the enum if needed. 4232 for (unsigned i = 0; i != NumElements; ++i) { 4233 EnumConstantDecl *ECD = 4234 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4235 if (!ECD) continue; // Already issued a diagnostic. 4236 4237 // Standard C says the enumerators have int type, but we allow, as an 4238 // extension, the enumerators to be larger than int size. If each 4239 // enumerator value fits in an int, type it as an int, otherwise type it the 4240 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4241 // that X has type 'int', not 'unsigned'. 4242 if (ECD->getType() == Context.IntTy) { 4243 // Make sure the init value is signed. 4244 llvm::APSInt IV = ECD->getInitVal(); 4245 IV.setIsSigned(true); 4246 ECD->setInitVal(IV); 4247 4248 if (getLangOptions().CPlusPlus) 4249 // C++ [dcl.enum]p4: Following the closing brace of an 4250 // enum-specifier, each enumerator has the type of its 4251 // enumeration. 4252 ECD->setType(EnumType); 4253 continue; // Already int type. 4254 } 4255 4256 // Determine whether the value fits into an int. 4257 llvm::APSInt InitVal = ECD->getInitVal(); 4258 bool FitsInInt; 4259 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4260 FitsInInt = InitVal.getActiveBits() < IntWidth; 4261 else 4262 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4263 4264 // If it fits into an integer type, force it. Otherwise force it to match 4265 // the enum decl type. 4266 QualType NewTy; 4267 unsigned NewWidth; 4268 bool NewSign; 4269 if (FitsInInt) { 4270 NewTy = Context.IntTy; 4271 NewWidth = IntWidth; 4272 NewSign = true; 4273 } else if (ECD->getType() == BestType) { 4274 // Already the right type! 4275 if (getLangOptions().CPlusPlus) 4276 // C++ [dcl.enum]p4: Following the closing brace of an 4277 // enum-specifier, each enumerator has the type of its 4278 // enumeration. 4279 ECD->setType(EnumType); 4280 continue; 4281 } else { 4282 NewTy = BestType; 4283 NewWidth = BestWidth; 4284 NewSign = BestType->isSignedIntegerType(); 4285 } 4286 4287 // Adjust the APSInt value. 4288 InitVal.extOrTrunc(NewWidth); 4289 InitVal.setIsSigned(NewSign); 4290 ECD->setInitVal(InitVal); 4291 4292 // Adjust the Expr initializer and type. 4293 if (ECD->getInitExpr()) 4294 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4295 /*isLvalue=*/false)); 4296 if (getLangOptions().CPlusPlus) 4297 // C++ [dcl.enum]p4: Following the closing brace of an 4298 // enum-specifier, each enumerator has the type of its 4299 // enumeration. 4300 ECD->setType(EnumType); 4301 else 4302 ECD->setType(NewTy); 4303 } 4304 4305 Enum->completeDefinition(Context, BestType); 4306} 4307 4308Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4309 ExprArg expr) { 4310 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4311 4312 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4313 Loc, AsmString)); 4314} 4315