SemaDecl.cpp revision 2c59d3c19715cb318a0a5939c735b8345d14d281
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/Analysis/CFG.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Basic/PartialDiagnostic.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/Basic/TargetInfo.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/BitVector.h" 33#include "llvm/ADT/STLExtras.h" 34#include <algorithm> 35#include <functional> 36#include <queue> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, const CXXScopeSpec *SS, 65 bool isClassName) { 66 // C++ [temp.res]p3: 67 // A qualified-id that refers to a type and in which the 68 // nested-name-specifier depends on a template-parameter (14.6.2) 69 // shall be prefixed by the keyword typename to indicate that the 70 // qualified-id denotes a type, forming an 71 // elaborated-type-specifier (7.1.5.3). 72 // 73 // We therefore do not perform any name lookup if the result would 74 // refer to a member of an unknown specialization. 75 if (SS && isUnknownSpecialization(*SS)) { 76 if (!isClassName) 77 return 0; 78 79 // We know from the grammar that this name refers to a type, so build a 80 // TypenameType node to describe the type. 81 // FIXME: Record somewhere that this TypenameType node has no "typename" 82 // keyword associated with it. 83 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 84 II, SS->getRange()).getAsOpaquePtr(); 85 } 86 87 LookupResult Result 88 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 89 90 NamedDecl *IIDecl = 0; 91 switch (Result.getKind()) { 92 case LookupResult::NotFound: 93 case LookupResult::FoundOverloaded: 94 return 0; 95 96 case LookupResult::AmbiguousBaseSubobjectTypes: 97 case LookupResult::AmbiguousBaseSubobjects: 98 case LookupResult::AmbiguousReference: { 99 // Look to see if we have a type anywhere in the list of results. 100 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 101 Res != ResEnd; ++Res) { 102 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 103 if (!IIDecl || 104 (*Res)->getLocation().getRawEncoding() < 105 IIDecl->getLocation().getRawEncoding()) 106 IIDecl = *Res; 107 } 108 } 109 110 if (!IIDecl) { 111 // None of the entities we found is a type, so there is no way 112 // to even assume that the result is a type. In this case, don't 113 // complain about the ambiguity. The parser will either try to 114 // perform this lookup again (e.g., as an object name), which 115 // will produce the ambiguity, or will complain that it expected 116 // a type name. 117 Result.Destroy(); 118 return 0; 119 } 120 121 // We found a type within the ambiguous lookup; diagnose the 122 // ambiguity and then return that type. This might be the right 123 // answer, or it might not be, but it suppresses any attempt to 124 // perform the name lookup again. 125 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 126 break; 127 } 128 129 case LookupResult::Found: 130 IIDecl = Result.getAsDecl(); 131 break; 132 } 133 134 if (IIDecl) { 135 QualType T; 136 137 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 138 // Check whether we can use this type 139 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 140 141 if (getLangOptions().CPlusPlus) { 142 // C++ [temp.local]p2: 143 // Within the scope of a class template specialization or 144 // partial specialization, when the injected-class-name is 145 // not followed by a <, it is equivalent to the 146 // injected-class-name followed by the template-argument s 147 // of the class template specialization or partial 148 // specialization enclosed in <>. 149 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 150 if (RD->isInjectedClassName()) 151 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 152 T = Template->getInjectedClassNameType(Context); 153 } 154 155 if (T.isNull()) 156 T = Context.getTypeDeclType(TD); 157 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 158 // Check whether we can use this interface. 159 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 160 161 T = Context.getObjCInterfaceType(IDecl); 162 } else 163 return 0; 164 165 if (SS) 166 T = getQualifiedNameType(*SS, T); 167 168 return T.getAsOpaquePtr(); 169 } 170 171 return 0; 172} 173 174/// isTagName() - This method is called *for error recovery purposes only* 175/// to determine if the specified name is a valid tag name ("struct foo"). If 176/// so, this returns the TST for the tag corresponding to it (TST_enum, 177/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 178/// where the user forgot to specify the tag. 179DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 180 // Do a tag name lookup in this scope. 181 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 182 if (R.getKind() == LookupResult::Found) 183 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 184 switch (TD->getTagKind()) { 185 case TagDecl::TK_struct: return DeclSpec::TST_struct; 186 case TagDecl::TK_union: return DeclSpec::TST_union; 187 case TagDecl::TK_class: return DeclSpec::TST_class; 188 case TagDecl::TK_enum: return DeclSpec::TST_enum; 189 } 190 } 191 192 return DeclSpec::TST_unspecified; 193} 194 195 196// Determines the context to return to after temporarily entering a 197// context. This depends in an unnecessarily complicated way on the 198// exact ordering of callbacks from the parser. 199DeclContext *Sema::getContainingDC(DeclContext *DC) { 200 201 // Functions defined inline within classes aren't parsed until we've 202 // finished parsing the top-level class, so the top-level class is 203 // the context we'll need to return to. 204 if (isa<FunctionDecl>(DC)) { 205 DC = DC->getLexicalParent(); 206 207 // A function not defined within a class will always return to its 208 // lexical context. 209 if (!isa<CXXRecordDecl>(DC)) 210 return DC; 211 212 // A C++ inline method/friend is parsed *after* the topmost class 213 // it was declared in is fully parsed ("complete"); the topmost 214 // class is the context we need to return to. 215 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 216 DC = RD; 217 218 // Return the declaration context of the topmost class the inline method is 219 // declared in. 220 return DC; 221 } 222 223 if (isa<ObjCMethodDecl>(DC)) 224 return Context.getTranslationUnitDecl(); 225 226 return DC->getLexicalParent(); 227} 228 229void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 230 assert(getContainingDC(DC) == CurContext && 231 "The next DeclContext should be lexically contained in the current one."); 232 CurContext = DC; 233 S->setEntity(DC); 234} 235 236void Sema::PopDeclContext() { 237 assert(CurContext && "DeclContext imbalance!"); 238 239 CurContext = getContainingDC(CurContext); 240} 241 242/// EnterDeclaratorContext - Used when we must lookup names in the context 243/// of a declarator's nested name specifier. 244void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 245 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 246 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 247 CurContext = DC; 248 assert(CurContext && "No context?"); 249 S->setEntity(CurContext); 250} 251 252void Sema::ExitDeclaratorContext(Scope *S) { 253 S->setEntity(PreDeclaratorDC); 254 PreDeclaratorDC = 0; 255 256 // Reset CurContext to the nearest enclosing context. 257 while (!S->getEntity() && S->getParent()) 258 S = S->getParent(); 259 CurContext = static_cast<DeclContext*>(S->getEntity()); 260 assert(CurContext && "No context?"); 261} 262 263/// \brief Determine whether we allow overloading of the function 264/// PrevDecl with another declaration. 265/// 266/// This routine determines whether overloading is possible, not 267/// whether some new function is actually an overload. It will return 268/// true in C++ (where we can always provide overloads) or, as an 269/// extension, in C when the previous function is already an 270/// overloaded function declaration or has the "overloadable" 271/// attribute. 272static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 273 if (Context.getLangOptions().CPlusPlus) 274 return true; 275 276 if (isa<OverloadedFunctionDecl>(PrevDecl)) 277 return true; 278 279 return PrevDecl->getAttr<OverloadableAttr>() != 0; 280} 281 282/// Add this decl to the scope shadowed decl chains. 283void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 284 // Move up the scope chain until we find the nearest enclosing 285 // non-transparent context. The declaration will be introduced into this 286 // scope. 287 while (S->getEntity() && 288 ((DeclContext *)S->getEntity())->isTransparentContext()) 289 S = S->getParent(); 290 291 S->AddDecl(DeclPtrTy::make(D)); 292 293 // Add scoped declarations into their context, so that they can be 294 // found later. Declarations without a context won't be inserted 295 // into any context. 296 if (AddToContext) 297 CurContext->addDecl(D); 298 299 // C++ [basic.scope]p4: 300 // -- exactly one declaration shall declare a class name or 301 // enumeration name that is not a typedef name and the other 302 // declarations shall all refer to the same object or 303 // enumerator, or all refer to functions and function templates; 304 // in this case the class name or enumeration name is hidden. 305 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 306 // We are pushing the name of a tag (enum or class). 307 if (CurContext->getLookupContext() 308 == TD->getDeclContext()->getLookupContext()) { 309 // We're pushing the tag into the current context, which might 310 // require some reshuffling in the identifier resolver. 311 IdentifierResolver::iterator 312 I = IdResolver.begin(TD->getDeclName()), 313 IEnd = IdResolver.end(); 314 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 315 NamedDecl *PrevDecl = *I; 316 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 317 PrevDecl = *I, ++I) { 318 if (TD->declarationReplaces(*I)) { 319 // This is a redeclaration. Remove it from the chain and 320 // break out, so that we'll add in the shadowed 321 // declaration. 322 S->RemoveDecl(DeclPtrTy::make(*I)); 323 if (PrevDecl == *I) { 324 IdResolver.RemoveDecl(*I); 325 IdResolver.AddDecl(TD); 326 return; 327 } else { 328 IdResolver.RemoveDecl(*I); 329 break; 330 } 331 } 332 } 333 334 // There is already a declaration with the same name in the same 335 // scope, which is not a tag declaration. It must be found 336 // before we find the new declaration, so insert the new 337 // declaration at the end of the chain. 338 IdResolver.AddShadowedDecl(TD, PrevDecl); 339 340 return; 341 } 342 } 343 } else if ((isa<FunctionDecl>(D) && 344 AllowOverloadingOfFunction(D, Context)) || 345 isa<FunctionTemplateDecl>(D)) { 346 // We are pushing the name of a function or function template, 347 // which might be an overloaded name. 348 IdentifierResolver::iterator Redecl 349 = std::find_if(IdResolver.begin(D->getDeclName()), 350 IdResolver.end(), 351 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 352 D)); 353 if (Redecl != IdResolver.end() && 354 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 355 // There is already a declaration of a function on our 356 // IdResolver chain. Replace it with this declaration. 357 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 358 IdResolver.RemoveDecl(*Redecl); 359 } 360 } else if (isa<ObjCInterfaceDecl>(D)) { 361 // We're pushing an Objective-C interface into the current 362 // context. If there is already an alias declaration, remove it first. 363 for (IdentifierResolver::iterator 364 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 365 I != IEnd; ++I) { 366 if (isa<ObjCCompatibleAliasDecl>(*I)) { 367 S->RemoveDecl(DeclPtrTy::make(*I)); 368 IdResolver.RemoveDecl(*I); 369 break; 370 } 371 } 372 } 373 374 IdResolver.AddDecl(D); 375} 376 377void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 378 if (S->decl_empty()) return; 379 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 380 "Scope shouldn't contain decls!"); 381 382 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 383 I != E; ++I) { 384 Decl *TmpD = (*I).getAs<Decl>(); 385 assert(TmpD && "This decl didn't get pushed??"); 386 387 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 388 NamedDecl *D = cast<NamedDecl>(TmpD); 389 390 if (!D->getDeclName()) continue; 391 392 // Remove this name from our lexical scope. 393 IdResolver.RemoveDecl(D); 394 } 395} 396 397/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 398/// return 0 if one not found. 399ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 400 // The third "scope" argument is 0 since we aren't enabling lazy built-in 401 // creation from this context. 402 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 403 404 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 405} 406 407/// getNonFieldDeclScope - Retrieves the innermost scope, starting 408/// from S, where a non-field would be declared. This routine copes 409/// with the difference between C and C++ scoping rules in structs and 410/// unions. For example, the following code is well-formed in C but 411/// ill-formed in C++: 412/// @code 413/// struct S6 { 414/// enum { BAR } e; 415/// }; 416/// 417/// void test_S6() { 418/// struct S6 a; 419/// a.e = BAR; 420/// } 421/// @endcode 422/// For the declaration of BAR, this routine will return a different 423/// scope. The scope S will be the scope of the unnamed enumeration 424/// within S6. In C++, this routine will return the scope associated 425/// with S6, because the enumeration's scope is a transparent 426/// context but structures can contain non-field names. In C, this 427/// routine will return the translation unit scope, since the 428/// enumeration's scope is a transparent context and structures cannot 429/// contain non-field names. 430Scope *Sema::getNonFieldDeclScope(Scope *S) { 431 while (((S->getFlags() & Scope::DeclScope) == 0) || 432 (S->getEntity() && 433 ((DeclContext *)S->getEntity())->isTransparentContext()) || 434 (S->isClassScope() && !getLangOptions().CPlusPlus)) 435 S = S->getParent(); 436 return S; 437} 438 439void Sema::InitBuiltinVaListType() { 440 if (!Context.getBuiltinVaListType().isNull()) 441 return; 442 443 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 444 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 445 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 446 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 447} 448 449/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 450/// file scope. lazily create a decl for it. ForRedeclaration is true 451/// if we're creating this built-in in anticipation of redeclaring the 452/// built-in. 453NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 454 Scope *S, bool ForRedeclaration, 455 SourceLocation Loc) { 456 Builtin::ID BID = (Builtin::ID)bid; 457 458 if (Context.BuiltinInfo.hasVAListUse(BID)) 459 InitBuiltinVaListType(); 460 461 ASTContext::GetBuiltinTypeError Error; 462 QualType R = Context.GetBuiltinType(BID, Error); 463 switch (Error) { 464 case ASTContext::GE_None: 465 // Okay 466 break; 467 468 case ASTContext::GE_Missing_stdio: 469 if (ForRedeclaration) 470 Diag(Loc, diag::err_implicit_decl_requires_stdio) 471 << Context.BuiltinInfo.GetName(BID); 472 return 0; 473 474 case ASTContext::GE_Missing_setjmp: 475 if (ForRedeclaration) 476 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 477 << Context.BuiltinInfo.GetName(BID); 478 return 0; 479 } 480 481 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 482 Diag(Loc, diag::ext_implicit_lib_function_decl) 483 << Context.BuiltinInfo.GetName(BID) 484 << R; 485 if (Context.BuiltinInfo.getHeaderName(BID) && 486 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 487 != Diagnostic::Ignored) 488 Diag(Loc, diag::note_please_include_header) 489 << Context.BuiltinInfo.getHeaderName(BID) 490 << Context.BuiltinInfo.GetName(BID); 491 } 492 493 FunctionDecl *New = FunctionDecl::Create(Context, 494 Context.getTranslationUnitDecl(), 495 Loc, II, R, /*DInfo=*/0, 496 FunctionDecl::Extern, false, 497 /*hasPrototype=*/true); 498 New->setImplicit(); 499 500 // Create Decl objects for each parameter, adding them to the 501 // FunctionDecl. 502 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 503 llvm::SmallVector<ParmVarDecl*, 16> Params; 504 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 505 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 506 FT->getArgType(i), /*DInfo=*/0, 507 VarDecl::None, 0)); 508 New->setParams(Context, Params.data(), Params.size()); 509 } 510 511 AddKnownFunctionAttributes(New); 512 513 // TUScope is the translation-unit scope to insert this function into. 514 // FIXME: This is hideous. We need to teach PushOnScopeChains to 515 // relate Scopes to DeclContexts, and probably eliminate CurContext 516 // entirely, but we're not there yet. 517 DeclContext *SavedContext = CurContext; 518 CurContext = Context.getTranslationUnitDecl(); 519 PushOnScopeChains(New, TUScope); 520 CurContext = SavedContext; 521 return New; 522} 523 524/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 525/// everything from the standard library is defined. 526NamespaceDecl *Sema::GetStdNamespace() { 527 if (!StdNamespace) { 528 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 529 DeclContext *Global = Context.getTranslationUnitDecl(); 530 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 531 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 532 } 533 return StdNamespace; 534} 535 536/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 537/// same name and scope as a previous declaration 'Old'. Figure out 538/// how to resolve this situation, merging decls or emitting 539/// diagnostics as appropriate. If there was an error, set New to be invalid. 540/// 541void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 542 // If either decl is known invalid already, set the new one to be invalid and 543 // don't bother doing any merging checks. 544 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 545 return New->setInvalidDecl(); 546 547 // Allow multiple definitions for ObjC built-in typedefs. 548 // FIXME: Verify the underlying types are equivalent! 549 if (getLangOptions().ObjC1) { 550 const IdentifierInfo *TypeID = New->getIdentifier(); 551 switch (TypeID->getLength()) { 552 default: break; 553 case 2: 554 if (!TypeID->isStr("id")) 555 break; 556 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 557 // Install the built-in type for 'id', ignoring the current definition. 558 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 559 return; 560 case 5: 561 if (!TypeID->isStr("Class")) 562 break; 563 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 564 // Install the built-in type for 'Class', ignoring the current definition. 565 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 566 return; 567 case 3: 568 if (!TypeID->isStr("SEL")) 569 break; 570 Context.setObjCSelType(Context.getTypeDeclType(New)); 571 return; 572 case 8: 573 if (!TypeID->isStr("Protocol")) 574 break; 575 Context.setObjCProtoType(New->getUnderlyingType()); 576 return; 577 } 578 // Fall through - the typedef name was not a builtin type. 579 } 580 // Verify the old decl was also a type. 581 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 582 if (!Old) { 583 Diag(New->getLocation(), diag::err_redefinition_different_kind) 584 << New->getDeclName(); 585 if (OldD->getLocation().isValid()) 586 Diag(OldD->getLocation(), diag::note_previous_definition); 587 return New->setInvalidDecl(); 588 } 589 590 // Determine the "old" type we'll use for checking and diagnostics. 591 QualType OldType; 592 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 593 OldType = OldTypedef->getUnderlyingType(); 594 else 595 OldType = Context.getTypeDeclType(Old); 596 597 // If the typedef types are not identical, reject them in all languages and 598 // with any extensions enabled. 599 600 if (OldType != New->getUnderlyingType() && 601 Context.getCanonicalType(OldType) != 602 Context.getCanonicalType(New->getUnderlyingType())) { 603 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 604 << New->getUnderlyingType() << OldType; 605 if (Old->getLocation().isValid()) 606 Diag(Old->getLocation(), diag::note_previous_definition); 607 return New->setInvalidDecl(); 608 } 609 610 if (getLangOptions().Microsoft) 611 return; 612 613 // C++ [dcl.typedef]p2: 614 // In a given non-class scope, a typedef specifier can be used to 615 // redefine the name of any type declared in that scope to refer 616 // to the type to which it already refers. 617 if (getLangOptions().CPlusPlus) { 618 if (!isa<CXXRecordDecl>(CurContext)) 619 return; 620 Diag(New->getLocation(), diag::err_redefinition) 621 << New->getDeclName(); 622 Diag(Old->getLocation(), diag::note_previous_definition); 623 return New->setInvalidDecl(); 624 } 625 626 // If we have a redefinition of a typedef in C, emit a warning. This warning 627 // is normally mapped to an error, but can be controlled with 628 // -Wtypedef-redefinition. If either the original or the redefinition is 629 // in a system header, don't emit this for compatibility with GCC. 630 if (PP.getDiagnostics().getSuppressSystemWarnings() && 631 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 632 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 633 return; 634 635 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 636 << New->getDeclName(); 637 Diag(Old->getLocation(), diag::note_previous_definition); 638 return; 639} 640 641/// DeclhasAttr - returns true if decl Declaration already has the target 642/// attribute. 643static bool 644DeclHasAttr(const Decl *decl, const Attr *target) { 645 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 646 if (attr->getKind() == target->getKind()) 647 return true; 648 649 return false; 650} 651 652/// MergeAttributes - append attributes from the Old decl to the New one. 653static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 654 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 655 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 656 Attr *NewAttr = attr->clone(C); 657 NewAttr->setInherited(true); 658 New->addAttr(NewAttr); 659 } 660 } 661} 662 663/// Used in MergeFunctionDecl to keep track of function parameters in 664/// C. 665struct GNUCompatibleParamWarning { 666 ParmVarDecl *OldParm; 667 ParmVarDecl *NewParm; 668 QualType PromotedType; 669}; 670 671/// MergeFunctionDecl - We just parsed a function 'New' from 672/// declarator D which has the same name and scope as a previous 673/// declaration 'Old'. Figure out how to resolve this situation, 674/// merging decls or emitting diagnostics as appropriate. 675/// 676/// In C++, New and Old must be declarations that are not 677/// overloaded. Use IsOverload to determine whether New and Old are 678/// overloaded, and to select the Old declaration that New should be 679/// merged with. 680/// 681/// Returns true if there was an error, false otherwise. 682bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 683 assert(!isa<OverloadedFunctionDecl>(OldD) && 684 "Cannot merge with an overloaded function declaration"); 685 686 // Verify the old decl was also a function. 687 FunctionDecl *Old = 0; 688 if (FunctionTemplateDecl *OldFunctionTemplate 689 = dyn_cast<FunctionTemplateDecl>(OldD)) 690 Old = OldFunctionTemplate->getTemplatedDecl(); 691 else 692 Old = dyn_cast<FunctionDecl>(OldD); 693 if (!Old) { 694 Diag(New->getLocation(), diag::err_redefinition_different_kind) 695 << New->getDeclName(); 696 Diag(OldD->getLocation(), diag::note_previous_definition); 697 return true; 698 } 699 700 // Determine whether the previous declaration was a definition, 701 // implicit declaration, or a declaration. 702 diag::kind PrevDiag; 703 if (Old->isThisDeclarationADefinition()) 704 PrevDiag = diag::note_previous_definition; 705 else if (Old->isImplicit()) 706 PrevDiag = diag::note_previous_implicit_declaration; 707 else 708 PrevDiag = diag::note_previous_declaration; 709 710 QualType OldQType = Context.getCanonicalType(Old->getType()); 711 QualType NewQType = Context.getCanonicalType(New->getType()); 712 713 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 714 New->getStorageClass() == FunctionDecl::Static && 715 Old->getStorageClass() != FunctionDecl::Static) { 716 Diag(New->getLocation(), diag::err_static_non_static) 717 << New; 718 Diag(Old->getLocation(), PrevDiag); 719 return true; 720 } 721 722 if (getLangOptions().CPlusPlus) { 723 // (C++98 13.1p2): 724 // Certain function declarations cannot be overloaded: 725 // -- Function declarations that differ only in the return type 726 // cannot be overloaded. 727 QualType OldReturnType 728 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 729 QualType NewReturnType 730 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 731 if (OldReturnType != NewReturnType) { 732 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 733 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 734 return true; 735 } 736 737 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 738 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 739 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 740 NewMethod->getLexicalDeclContext()->isRecord()) { 741 // -- Member function declarations with the same name and the 742 // same parameter types cannot be overloaded if any of them 743 // is a static member function declaration. 744 if (OldMethod->isStatic() || NewMethod->isStatic()) { 745 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 746 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 747 return true; 748 } 749 750 // C++ [class.mem]p1: 751 // [...] A member shall not be declared twice in the 752 // member-specification, except that a nested class or member 753 // class template can be declared and then later defined. 754 unsigned NewDiag; 755 if (isa<CXXConstructorDecl>(OldMethod)) 756 NewDiag = diag::err_constructor_redeclared; 757 else if (isa<CXXDestructorDecl>(NewMethod)) 758 NewDiag = diag::err_destructor_redeclared; 759 else if (isa<CXXConversionDecl>(NewMethod)) 760 NewDiag = diag::err_conv_function_redeclared; 761 else 762 NewDiag = diag::err_member_redeclared; 763 764 Diag(New->getLocation(), NewDiag); 765 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 766 } 767 768 // (C++98 8.3.5p3): 769 // All declarations for a function shall agree exactly in both the 770 // return type and the parameter-type-list. 771 if (OldQType == NewQType) 772 return MergeCompatibleFunctionDecls(New, Old); 773 774 // Fall through for conflicting redeclarations and redefinitions. 775 } 776 777 // C: Function types need to be compatible, not identical. This handles 778 // duplicate function decls like "void f(int); void f(enum X);" properly. 779 if (!getLangOptions().CPlusPlus && 780 Context.typesAreCompatible(OldQType, NewQType)) { 781 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 782 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 783 const FunctionProtoType *OldProto = 0; 784 if (isa<FunctionNoProtoType>(NewFuncType) && 785 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 786 // The old declaration provided a function prototype, but the 787 // new declaration does not. Merge in the prototype. 788 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 789 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 790 OldProto->arg_type_end()); 791 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 792 ParamTypes.data(), ParamTypes.size(), 793 OldProto->isVariadic(), 794 OldProto->getTypeQuals()); 795 New->setType(NewQType); 796 New->setHasInheritedPrototype(); 797 798 // Synthesize a parameter for each argument type. 799 llvm::SmallVector<ParmVarDecl*, 16> Params; 800 for (FunctionProtoType::arg_type_iterator 801 ParamType = OldProto->arg_type_begin(), 802 ParamEnd = OldProto->arg_type_end(); 803 ParamType != ParamEnd; ++ParamType) { 804 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 805 SourceLocation(), 0, 806 *ParamType, /*DInfo=*/0, 807 VarDecl::None, 0); 808 Param->setImplicit(); 809 Params.push_back(Param); 810 } 811 812 New->setParams(Context, Params.data(), Params.size()); 813 } 814 815 return MergeCompatibleFunctionDecls(New, Old); 816 } 817 818 // GNU C permits a K&R definition to follow a prototype declaration 819 // if the declared types of the parameters in the K&R definition 820 // match the types in the prototype declaration, even when the 821 // promoted types of the parameters from the K&R definition differ 822 // from the types in the prototype. GCC then keeps the types from 823 // the prototype. 824 // 825 // If a variadic prototype is followed by a non-variadic K&R definition, 826 // the K&R definition becomes variadic. This is sort of an edge case, but 827 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 828 // C99 6.9.1p8. 829 if (!getLangOptions().CPlusPlus && 830 Old->hasPrototype() && !New->hasPrototype() && 831 New->getType()->getAsFunctionProtoType() && 832 Old->getNumParams() == New->getNumParams()) { 833 llvm::SmallVector<QualType, 16> ArgTypes; 834 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 835 const FunctionProtoType *OldProto 836 = Old->getType()->getAsFunctionProtoType(); 837 const FunctionProtoType *NewProto 838 = New->getType()->getAsFunctionProtoType(); 839 840 // Determine whether this is the GNU C extension. 841 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 842 NewProto->getResultType()); 843 bool LooseCompatible = !MergedReturn.isNull(); 844 for (unsigned Idx = 0, End = Old->getNumParams(); 845 LooseCompatible && Idx != End; ++Idx) { 846 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 847 ParmVarDecl *NewParm = New->getParamDecl(Idx); 848 if (Context.typesAreCompatible(OldParm->getType(), 849 NewProto->getArgType(Idx))) { 850 ArgTypes.push_back(NewParm->getType()); 851 } else if (Context.typesAreCompatible(OldParm->getType(), 852 NewParm->getType())) { 853 GNUCompatibleParamWarning Warn 854 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 855 Warnings.push_back(Warn); 856 ArgTypes.push_back(NewParm->getType()); 857 } else 858 LooseCompatible = false; 859 } 860 861 if (LooseCompatible) { 862 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 863 Diag(Warnings[Warn].NewParm->getLocation(), 864 diag::ext_param_promoted_not_compatible_with_prototype) 865 << Warnings[Warn].PromotedType 866 << Warnings[Warn].OldParm->getType(); 867 Diag(Warnings[Warn].OldParm->getLocation(), 868 diag::note_previous_declaration); 869 } 870 871 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 872 ArgTypes.size(), 873 OldProto->isVariadic(), 0)); 874 return MergeCompatibleFunctionDecls(New, Old); 875 } 876 877 // Fall through to diagnose conflicting types. 878 } 879 880 // A function that has already been declared has been redeclared or defined 881 // with a different type- show appropriate diagnostic 882 if (unsigned BuiltinID = Old->getBuiltinID()) { 883 // The user has declared a builtin function with an incompatible 884 // signature. 885 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 886 // The function the user is redeclaring is a library-defined 887 // function like 'malloc' or 'printf'. Warn about the 888 // redeclaration, then pretend that we don't know about this 889 // library built-in. 890 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 891 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 892 << Old << Old->getType(); 893 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 894 Old->setInvalidDecl(); 895 return false; 896 } 897 898 PrevDiag = diag::note_previous_builtin_declaration; 899 } 900 901 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 902 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 903 return true; 904} 905 906/// \brief Completes the merge of two function declarations that are 907/// known to be compatible. 908/// 909/// This routine handles the merging of attributes and other 910/// properties of function declarations form the old declaration to 911/// the new declaration, once we know that New is in fact a 912/// redeclaration of Old. 913/// 914/// \returns false 915bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 916 // Merge the attributes 917 MergeAttributes(New, Old, Context); 918 919 // Merge the storage class. 920 if (Old->getStorageClass() != FunctionDecl::Extern && 921 Old->getStorageClass() != FunctionDecl::None) 922 New->setStorageClass(Old->getStorageClass()); 923 924 // Merge "pure" flag. 925 if (Old->isPure()) 926 New->setPure(); 927 928 // Merge the "deleted" flag. 929 if (Old->isDeleted()) 930 New->setDeleted(); 931 932 if (getLangOptions().CPlusPlus) 933 return MergeCXXFunctionDecl(New, Old); 934 935 return false; 936} 937 938/// MergeVarDecl - We just parsed a variable 'New' which has the same name 939/// and scope as a previous declaration 'Old'. Figure out how to resolve this 940/// situation, merging decls or emitting diagnostics as appropriate. 941/// 942/// Tentative definition rules (C99 6.9.2p2) are checked by 943/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 944/// definitions here, since the initializer hasn't been attached. 945/// 946void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 947 // If either decl is invalid, make sure the new one is marked invalid and 948 // don't do any other checking. 949 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 950 return New->setInvalidDecl(); 951 952 // Verify the old decl was also a variable. 953 VarDecl *Old = dyn_cast<VarDecl>(OldD); 954 if (!Old) { 955 Diag(New->getLocation(), diag::err_redefinition_different_kind) 956 << New->getDeclName(); 957 Diag(OldD->getLocation(), diag::note_previous_definition); 958 return New->setInvalidDecl(); 959 } 960 961 MergeAttributes(New, Old, Context); 962 963 // Merge the types 964 QualType MergedT; 965 if (getLangOptions().CPlusPlus) { 966 if (Context.hasSameType(New->getType(), Old->getType())) 967 MergedT = New->getType(); 968 // C++ [basic.types]p7: 969 // [...] The declared type of an array object might be an array of 970 // unknown size and therefore be incomplete at one point in a 971 // translation unit and complete later on; [...] 972 else if (Old->getType()->isIncompleteArrayType() && 973 New->getType()->isArrayType()) { 974 CanQual<ArrayType> OldArray 975 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 976 CanQual<ArrayType> NewArray 977 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 978 if (OldArray->getElementType() == NewArray->getElementType()) 979 MergedT = New->getType(); 980 } 981 } else { 982 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 983 } 984 if (MergedT.isNull()) { 985 Diag(New->getLocation(), diag::err_redefinition_different_type) 986 << New->getDeclName(); 987 Diag(Old->getLocation(), diag::note_previous_definition); 988 return New->setInvalidDecl(); 989 } 990 New->setType(MergedT); 991 992 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 993 if (New->getStorageClass() == VarDecl::Static && 994 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 995 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 996 Diag(Old->getLocation(), diag::note_previous_definition); 997 return New->setInvalidDecl(); 998 } 999 // C99 6.2.2p4: 1000 // For an identifier declared with the storage-class specifier 1001 // extern in a scope in which a prior declaration of that 1002 // identifier is visible,23) if the prior declaration specifies 1003 // internal or external linkage, the linkage of the identifier at 1004 // the later declaration is the same as the linkage specified at 1005 // the prior declaration. If no prior declaration is visible, or 1006 // if the prior declaration specifies no linkage, then the 1007 // identifier has external linkage. 1008 if (New->hasExternalStorage() && Old->hasLinkage()) 1009 /* Okay */; 1010 else if (New->getStorageClass() != VarDecl::Static && 1011 Old->getStorageClass() == VarDecl::Static) { 1012 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1013 Diag(Old->getLocation(), diag::note_previous_definition); 1014 return New->setInvalidDecl(); 1015 } 1016 1017 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1018 1019 // FIXME: The test for external storage here seems wrong? We still 1020 // need to check for mismatches. 1021 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1022 // Don't complain about out-of-line definitions of static members. 1023 !(Old->getLexicalDeclContext()->isRecord() && 1024 !New->getLexicalDeclContext()->isRecord())) { 1025 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1026 Diag(Old->getLocation(), diag::note_previous_definition); 1027 return New->setInvalidDecl(); 1028 } 1029 1030 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1031 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1032 Diag(Old->getLocation(), diag::note_previous_definition); 1033 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1034 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1035 Diag(Old->getLocation(), diag::note_previous_definition); 1036 } 1037 1038 // Keep a chain of previous declarations. 1039 New->setPreviousDeclaration(Old); 1040} 1041 1042/// CheckFallThrough - Check that we don't fall off the end of a 1043/// Statement that should return a value. 1044/// 1045/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1046/// MaybeFallThrough iff we might or might not fall off the end and 1047/// NeverFallThrough iff we never fall off the end of the statement. We assume 1048/// that functions not marked noreturn will return. 1049Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1050 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1051 1052 // FIXME: They should never return 0, fix that, delete this code. 1053 if (cfg == 0) 1054 return NeverFallThrough; 1055 // The CFG leaves in dead things, and we don't want to dead code paths to 1056 // confuse us, so we mark all live things first. 1057 std::queue<CFGBlock*> workq; 1058 llvm::BitVector live(cfg->getNumBlockIDs()); 1059 // Prep work queue 1060 workq.push(&cfg->getEntry()); 1061 // Solve 1062 while (!workq.empty()) { 1063 CFGBlock *item = workq.front(); 1064 workq.pop(); 1065 live.set(item->getBlockID()); 1066 for (CFGBlock::succ_iterator I=item->succ_begin(), 1067 E=item->succ_end(); 1068 I != E; 1069 ++I) { 1070 if ((*I) && !live[(*I)->getBlockID()]) { 1071 live.set((*I)->getBlockID()); 1072 workq.push(*I); 1073 } 1074 } 1075 } 1076 1077 // Now we know what is live, we check the live precessors of the exit block 1078 // and look for fall through paths, being careful to ignore normal returns, 1079 // and exceptional paths. 1080 bool HasLiveReturn = false; 1081 bool HasFakeEdge = false; 1082 bool HasPlainEdge = false; 1083 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1084 E = cfg->getExit().pred_end(); 1085 I != E; 1086 ++I) { 1087 CFGBlock& B = **I; 1088 if (!live[B.getBlockID()]) 1089 continue; 1090 if (B.size() == 0) { 1091 // A labeled empty statement, or the entry block... 1092 HasPlainEdge = true; 1093 continue; 1094 } 1095 Stmt *S = B[B.size()-1]; 1096 if (isa<ReturnStmt>(S)) { 1097 HasLiveReturn = true; 1098 continue; 1099 } 1100 if (isa<ObjCAtThrowStmt>(S)) { 1101 HasFakeEdge = true; 1102 continue; 1103 } 1104 if (isa<CXXThrowExpr>(S)) { 1105 HasFakeEdge = true; 1106 continue; 1107 } 1108 bool NoReturnEdge = false; 1109 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1110 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1111 if (CEE->getType().getNoReturnAttr()) { 1112 NoReturnEdge = true; 1113 HasFakeEdge = true; 1114 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1115 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1116 if (FD->hasAttr<NoReturnAttr>()) { 1117 NoReturnEdge = true; 1118 HasFakeEdge = true; 1119 } 1120 } 1121 } 1122 } 1123 // FIXME: Add noreturn message sends. 1124 if (NoReturnEdge == false) 1125 HasPlainEdge = true; 1126 } 1127 if (!HasPlainEdge) 1128 return NeverFallThrough; 1129 if (HasFakeEdge || HasLiveReturn) 1130 return MaybeFallThrough; 1131 // This says AlwaysFallThrough for calls to functions that are not marked 1132 // noreturn, that don't return. If people would like this warning to be more 1133 // accurate, such functions should be marked as noreturn. 1134 return AlwaysFallThrough; 1135} 1136 1137/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1138/// function that should return a value. Check that we don't fall off the end 1139/// of a noreturn function. We assume that functions and blocks not marked 1140/// noreturn will return. 1141void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1142 // FIXME: Would be nice if we had a better way to control cascading errors, 1143 // but for now, avoid them. The problem is that when Parse sees: 1144 // int foo() { return a; } 1145 // The return is eaten and the Sema code sees just: 1146 // int foo() { } 1147 // which this code would then warn about. 1148 if (getDiagnostics().hasErrorOccurred()) 1149 return; 1150 bool ReturnsVoid = false; 1151 bool HasNoReturn = false; 1152 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1153 if (FD->getResultType()->isVoidType()) 1154 ReturnsVoid = true; 1155 if (FD->hasAttr<NoReturnAttr>()) 1156 HasNoReturn = true; 1157 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1158 if (MD->getResultType()->isVoidType()) 1159 ReturnsVoid = true; 1160 if (MD->hasAttr<NoReturnAttr>()) 1161 HasNoReturn = true; 1162 } 1163 1164 // Short circuit for compilation speed. 1165 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1166 == Diagnostic::Ignored || ReturnsVoid) 1167 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1168 == Diagnostic::Ignored || !HasNoReturn) 1169 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1170 == Diagnostic::Ignored || !ReturnsVoid)) 1171 return; 1172 // FIXME: Funtion try block 1173 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1174 switch (CheckFallThrough(Body)) { 1175 case MaybeFallThrough: 1176 if (HasNoReturn) 1177 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1178 else if (!ReturnsVoid) 1179 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1180 break; 1181 case AlwaysFallThrough: 1182 if (HasNoReturn) 1183 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1184 else if (!ReturnsVoid) 1185 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1186 break; 1187 case NeverFallThrough: 1188 if (ReturnsVoid) 1189 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1190 break; 1191 } 1192 } 1193} 1194 1195/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1196/// that should return a value. Check that we don't fall off the end of a 1197/// noreturn block. We assume that functions and blocks not marked noreturn 1198/// will return. 1199void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1200 // FIXME: Would be nice if we had a better way to control cascading errors, 1201 // but for now, avoid them. The problem is that when Parse sees: 1202 // int foo() { return a; } 1203 // The return is eaten and the Sema code sees just: 1204 // int foo() { } 1205 // which this code would then warn about. 1206 if (getDiagnostics().hasErrorOccurred()) 1207 return; 1208 bool ReturnsVoid = false; 1209 bool HasNoReturn = false; 1210 if (const FunctionType *FT = BlockTy->getPointeeType()->getAsFunctionType()) { 1211 if (FT->getResultType()->isVoidType()) 1212 ReturnsVoid = true; 1213 if (FT->getNoReturnAttr()) 1214 HasNoReturn = true; 1215 } 1216 1217 // Short circuit for compilation speed. 1218 if (ReturnsVoid 1219 && !HasNoReturn 1220 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1221 == Diagnostic::Ignored || !ReturnsVoid)) 1222 return; 1223 // FIXME: Funtion try block 1224 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1225 switch (CheckFallThrough(Body)) { 1226 case MaybeFallThrough: 1227 if (HasNoReturn) 1228 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1229 else if (!ReturnsVoid) 1230 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1231 break; 1232 case AlwaysFallThrough: 1233 if (HasNoReturn) 1234 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1235 else if (!ReturnsVoid) 1236 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1237 break; 1238 case NeverFallThrough: 1239 if (ReturnsVoid) 1240 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1241 break; 1242 } 1243 } 1244} 1245 1246/// CheckParmsForFunctionDef - Check that the parameters of the given 1247/// function are appropriate for the definition of a function. This 1248/// takes care of any checks that cannot be performed on the 1249/// declaration itself, e.g., that the types of each of the function 1250/// parameters are complete. 1251bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1252 bool HasInvalidParm = false; 1253 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1254 ParmVarDecl *Param = FD->getParamDecl(p); 1255 1256 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1257 // function declarator that is part of a function definition of 1258 // that function shall not have incomplete type. 1259 // 1260 // This is also C++ [dcl.fct]p6. 1261 if (!Param->isInvalidDecl() && 1262 RequireCompleteType(Param->getLocation(), Param->getType(), 1263 diag::err_typecheck_decl_incomplete_type)) { 1264 Param->setInvalidDecl(); 1265 HasInvalidParm = true; 1266 } 1267 1268 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1269 // declaration of each parameter shall include an identifier. 1270 if (Param->getIdentifier() == 0 && 1271 !Param->isImplicit() && 1272 !getLangOptions().CPlusPlus) 1273 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1274 } 1275 1276 return HasInvalidParm; 1277} 1278 1279/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1280/// no declarator (e.g. "struct foo;") is parsed. 1281Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1282 // FIXME: Error on auto/register at file scope 1283 // FIXME: Error on inline/virtual/explicit 1284 // FIXME: Error on invalid restrict 1285 // FIXME: Warn on useless __thread 1286 // FIXME: Warn on useless const/volatile 1287 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1288 // FIXME: Warn on useless attributes 1289 TagDecl *Tag = 0; 1290 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1291 DS.getTypeSpecType() == DeclSpec::TST_struct || 1292 DS.getTypeSpecType() == DeclSpec::TST_union || 1293 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1294 if (!DS.getTypeRep()) // We probably had an error 1295 return DeclPtrTy(); 1296 1297 // Note that the above type specs guarantee that the 1298 // type rep is a Decl, whereas in many of the others 1299 // it's a Type. 1300 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1301 } 1302 1303 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1304 if (!Record->getDeclName() && Record->isDefinition() && 1305 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1306 if (getLangOptions().CPlusPlus || 1307 Record->getDeclContext()->isRecord()) 1308 return BuildAnonymousStructOrUnion(S, DS, Record); 1309 1310 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1311 << DS.getSourceRange(); 1312 } 1313 1314 // Microsoft allows unnamed struct/union fields. Don't complain 1315 // about them. 1316 // FIXME: Should we support Microsoft's extensions in this area? 1317 if (Record->getDeclName() && getLangOptions().Microsoft) 1318 return DeclPtrTy::make(Tag); 1319 } 1320 1321 if (!DS.isMissingDeclaratorOk() && 1322 DS.getTypeSpecType() != DeclSpec::TST_error) { 1323 // Warn about typedefs of enums without names, since this is an 1324 // extension in both Microsoft an GNU. 1325 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1326 Tag && isa<EnumDecl>(Tag)) { 1327 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1328 << DS.getSourceRange(); 1329 return DeclPtrTy::make(Tag); 1330 } 1331 1332 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1333 << DS.getSourceRange(); 1334 return DeclPtrTy(); 1335 } 1336 1337 return DeclPtrTy::make(Tag); 1338} 1339 1340/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1341/// anonymous struct or union AnonRecord into the owning context Owner 1342/// and scope S. This routine will be invoked just after we realize 1343/// that an unnamed union or struct is actually an anonymous union or 1344/// struct, e.g., 1345/// 1346/// @code 1347/// union { 1348/// int i; 1349/// float f; 1350/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1351/// // f into the surrounding scope.x 1352/// @endcode 1353/// 1354/// This routine is recursive, injecting the names of nested anonymous 1355/// structs/unions into the owning context and scope as well. 1356bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1357 RecordDecl *AnonRecord) { 1358 bool Invalid = false; 1359 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1360 FEnd = AnonRecord->field_end(); 1361 F != FEnd; ++F) { 1362 if ((*F)->getDeclName()) { 1363 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1364 LookupOrdinaryName, true); 1365 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1366 // C++ [class.union]p2: 1367 // The names of the members of an anonymous union shall be 1368 // distinct from the names of any other entity in the 1369 // scope in which the anonymous union is declared. 1370 unsigned diagKind 1371 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1372 : diag::err_anonymous_struct_member_redecl; 1373 Diag((*F)->getLocation(), diagKind) 1374 << (*F)->getDeclName(); 1375 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1376 Invalid = true; 1377 } else { 1378 // C++ [class.union]p2: 1379 // For the purpose of name lookup, after the anonymous union 1380 // definition, the members of the anonymous union are 1381 // considered to have been defined in the scope in which the 1382 // anonymous union is declared. 1383 Owner->makeDeclVisibleInContext(*F); 1384 S->AddDecl(DeclPtrTy::make(*F)); 1385 IdResolver.AddDecl(*F); 1386 } 1387 } else if (const RecordType *InnerRecordType 1388 = (*F)->getType()->getAs<RecordType>()) { 1389 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1390 if (InnerRecord->isAnonymousStructOrUnion()) 1391 Invalid = Invalid || 1392 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1393 } 1394 } 1395 1396 return Invalid; 1397} 1398 1399/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1400/// anonymous structure or union. Anonymous unions are a C++ feature 1401/// (C++ [class.union]) and a GNU C extension; anonymous structures 1402/// are a GNU C and GNU C++ extension. 1403Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1404 RecordDecl *Record) { 1405 DeclContext *Owner = Record->getDeclContext(); 1406 1407 // Diagnose whether this anonymous struct/union is an extension. 1408 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1409 Diag(Record->getLocation(), diag::ext_anonymous_union); 1410 else if (!Record->isUnion()) 1411 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1412 1413 // C and C++ require different kinds of checks for anonymous 1414 // structs/unions. 1415 bool Invalid = false; 1416 if (getLangOptions().CPlusPlus) { 1417 const char* PrevSpec = 0; 1418 unsigned DiagID; 1419 // C++ [class.union]p3: 1420 // Anonymous unions declared in a named namespace or in the 1421 // global namespace shall be declared static. 1422 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1423 (isa<TranslationUnitDecl>(Owner) || 1424 (isa<NamespaceDecl>(Owner) && 1425 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1426 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1427 Invalid = true; 1428 1429 // Recover by adding 'static'. 1430 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1431 PrevSpec, DiagID); 1432 } 1433 // C++ [class.union]p3: 1434 // A storage class is not allowed in a declaration of an 1435 // anonymous union in a class scope. 1436 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1437 isa<RecordDecl>(Owner)) { 1438 Diag(DS.getStorageClassSpecLoc(), 1439 diag::err_anonymous_union_with_storage_spec); 1440 Invalid = true; 1441 1442 // Recover by removing the storage specifier. 1443 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1444 PrevSpec, DiagID); 1445 } 1446 1447 // C++ [class.union]p2: 1448 // The member-specification of an anonymous union shall only 1449 // define non-static data members. [Note: nested types and 1450 // functions cannot be declared within an anonymous union. ] 1451 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1452 MemEnd = Record->decls_end(); 1453 Mem != MemEnd; ++Mem) { 1454 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1455 // C++ [class.union]p3: 1456 // An anonymous union shall not have private or protected 1457 // members (clause 11). 1458 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1459 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1460 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1461 Invalid = true; 1462 } 1463 } else if ((*Mem)->isImplicit()) { 1464 // Any implicit members are fine. 1465 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1466 // This is a type that showed up in an 1467 // elaborated-type-specifier inside the anonymous struct or 1468 // union, but which actually declares a type outside of the 1469 // anonymous struct or union. It's okay. 1470 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1471 if (!MemRecord->isAnonymousStructOrUnion() && 1472 MemRecord->getDeclName()) { 1473 // This is a nested type declaration. 1474 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1475 << (int)Record->isUnion(); 1476 Invalid = true; 1477 } 1478 } else { 1479 // We have something that isn't a non-static data 1480 // member. Complain about it. 1481 unsigned DK = diag::err_anonymous_record_bad_member; 1482 if (isa<TypeDecl>(*Mem)) 1483 DK = diag::err_anonymous_record_with_type; 1484 else if (isa<FunctionDecl>(*Mem)) 1485 DK = diag::err_anonymous_record_with_function; 1486 else if (isa<VarDecl>(*Mem)) 1487 DK = diag::err_anonymous_record_with_static; 1488 Diag((*Mem)->getLocation(), DK) 1489 << (int)Record->isUnion(); 1490 Invalid = true; 1491 } 1492 } 1493 } 1494 1495 if (!Record->isUnion() && !Owner->isRecord()) { 1496 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1497 << (int)getLangOptions().CPlusPlus; 1498 Invalid = true; 1499 } 1500 1501 // Create a declaration for this anonymous struct/union. 1502 NamedDecl *Anon = 0; 1503 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1504 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1505 /*IdentifierInfo=*/0, 1506 Context.getTypeDeclType(Record), 1507 // FIXME: Type source info. 1508 /*DInfo=*/0, 1509 /*BitWidth=*/0, /*Mutable=*/false); 1510 Anon->setAccess(AS_public); 1511 if (getLangOptions().CPlusPlus) 1512 FieldCollector->Add(cast<FieldDecl>(Anon)); 1513 } else { 1514 VarDecl::StorageClass SC; 1515 switch (DS.getStorageClassSpec()) { 1516 default: assert(0 && "Unknown storage class!"); 1517 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1518 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1519 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1520 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1521 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1522 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1523 case DeclSpec::SCS_mutable: 1524 // mutable can only appear on non-static class members, so it's always 1525 // an error here 1526 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1527 Invalid = true; 1528 SC = VarDecl::None; 1529 break; 1530 } 1531 1532 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1533 /*IdentifierInfo=*/0, 1534 Context.getTypeDeclType(Record), 1535 // FIXME: Type source info. 1536 /*DInfo=*/0, 1537 SC); 1538 } 1539 Anon->setImplicit(); 1540 1541 // Add the anonymous struct/union object to the current 1542 // context. We'll be referencing this object when we refer to one of 1543 // its members. 1544 Owner->addDecl(Anon); 1545 1546 // Inject the members of the anonymous struct/union into the owning 1547 // context and into the identifier resolver chain for name lookup 1548 // purposes. 1549 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1550 Invalid = true; 1551 1552 // Mark this as an anonymous struct/union type. Note that we do not 1553 // do this until after we have already checked and injected the 1554 // members of this anonymous struct/union type, because otherwise 1555 // the members could be injected twice: once by DeclContext when it 1556 // builds its lookup table, and once by 1557 // InjectAnonymousStructOrUnionMembers. 1558 Record->setAnonymousStructOrUnion(true); 1559 1560 if (Invalid) 1561 Anon->setInvalidDecl(); 1562 1563 return DeclPtrTy::make(Anon); 1564} 1565 1566 1567/// GetNameForDeclarator - Determine the full declaration name for the 1568/// given Declarator. 1569DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1570 switch (D.getKind()) { 1571 case Declarator::DK_Abstract: 1572 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1573 return DeclarationName(); 1574 1575 case Declarator::DK_Normal: 1576 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1577 return DeclarationName(D.getIdentifier()); 1578 1579 case Declarator::DK_Constructor: { 1580 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1581 return Context.DeclarationNames.getCXXConstructorName( 1582 Context.getCanonicalType(Ty)); 1583 } 1584 1585 case Declarator::DK_Destructor: { 1586 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1587 return Context.DeclarationNames.getCXXDestructorName( 1588 Context.getCanonicalType(Ty)); 1589 } 1590 1591 case Declarator::DK_Conversion: { 1592 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1593 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1594 return Context.DeclarationNames.getCXXConversionFunctionName( 1595 Context.getCanonicalType(Ty)); 1596 } 1597 1598 case Declarator::DK_Operator: 1599 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1600 return Context.DeclarationNames.getCXXOperatorName( 1601 D.getOverloadedOperator()); 1602 } 1603 1604 assert(false && "Unknown name kind"); 1605 return DeclarationName(); 1606} 1607 1608/// isNearlyMatchingFunction - Determine whether the C++ functions 1609/// Declaration and Definition are "nearly" matching. This heuristic 1610/// is used to improve diagnostics in the case where an out-of-line 1611/// function definition doesn't match any declaration within 1612/// the class or namespace. 1613static bool isNearlyMatchingFunction(ASTContext &Context, 1614 FunctionDecl *Declaration, 1615 FunctionDecl *Definition) { 1616 if (Declaration->param_size() != Definition->param_size()) 1617 return false; 1618 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1619 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1620 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1621 1622 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1623 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1624 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1625 return false; 1626 } 1627 1628 return true; 1629} 1630 1631Sema::DeclPtrTy 1632Sema::HandleDeclarator(Scope *S, Declarator &D, 1633 MultiTemplateParamsArg TemplateParamLists, 1634 bool IsFunctionDefinition) { 1635 DeclarationName Name = GetNameForDeclarator(D); 1636 1637 // All of these full declarators require an identifier. If it doesn't have 1638 // one, the ParsedFreeStandingDeclSpec action should be used. 1639 if (!Name) { 1640 if (!D.isInvalidType()) // Reject this if we think it is valid. 1641 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1642 diag::err_declarator_need_ident) 1643 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1644 return DeclPtrTy(); 1645 } 1646 1647 // The scope passed in may not be a decl scope. Zip up the scope tree until 1648 // we find one that is. 1649 while ((S->getFlags() & Scope::DeclScope) == 0 || 1650 (S->getFlags() & Scope::TemplateParamScope) != 0) 1651 S = S->getParent(); 1652 1653 // If this is an out-of-line definition of a member of a class template 1654 // or class template partial specialization, we may need to rebuild the 1655 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1656 // for more information. 1657 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1658 // handle expressions properly. 1659 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1660 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1661 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1662 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1663 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1664 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1665 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1666 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1667 // FIXME: Preserve type source info. 1668 QualType T = GetTypeFromParser(DS.getTypeRep()); 1669 EnterDeclaratorContext(S, DC); 1670 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1671 ExitDeclaratorContext(S); 1672 if (T.isNull()) 1673 return DeclPtrTy(); 1674 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1675 } 1676 } 1677 1678 DeclContext *DC; 1679 NamedDecl *PrevDecl; 1680 NamedDecl *New; 1681 1682 DeclaratorInfo *DInfo = 0; 1683 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1684 1685 // See if this is a redefinition of a variable in the same scope. 1686 if (D.getCXXScopeSpec().isInvalid()) { 1687 DC = CurContext; 1688 PrevDecl = 0; 1689 D.setInvalidType(); 1690 } else if (!D.getCXXScopeSpec().isSet()) { 1691 LookupNameKind NameKind = LookupOrdinaryName; 1692 1693 // If the declaration we're planning to build will be a function 1694 // or object with linkage, then look for another declaration with 1695 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1696 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1697 /* Do nothing*/; 1698 else if (R->isFunctionType()) { 1699 if (CurContext->isFunctionOrMethod() || 1700 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1701 NameKind = LookupRedeclarationWithLinkage; 1702 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1703 NameKind = LookupRedeclarationWithLinkage; 1704 else if (CurContext->getLookupContext()->isTranslationUnit() && 1705 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1706 NameKind = LookupRedeclarationWithLinkage; 1707 1708 DC = CurContext; 1709 PrevDecl = LookupName(S, Name, NameKind, true, 1710 NameKind == LookupRedeclarationWithLinkage, 1711 D.getIdentifierLoc()); 1712 } else { // Something like "int foo::x;" 1713 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1714 1715 if (!DC) { 1716 // If we could not compute the declaration context, it's because the 1717 // declaration context is dependent but does not refer to a class, 1718 // class template, or class template partial specialization. Complain 1719 // and return early, to avoid the coming semantic disaster. 1720 Diag(D.getIdentifierLoc(), 1721 diag::err_template_qualified_declarator_no_match) 1722 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1723 << D.getCXXScopeSpec().getRange(); 1724 return DeclPtrTy(); 1725 } 1726 1727 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1728 1729 // C++ 7.3.1.2p2: 1730 // Members (including explicit specializations of templates) of a named 1731 // namespace can also be defined outside that namespace by explicit 1732 // qualification of the name being defined, provided that the entity being 1733 // defined was already declared in the namespace and the definition appears 1734 // after the point of declaration in a namespace that encloses the 1735 // declarations namespace. 1736 // 1737 // Note that we only check the context at this point. We don't yet 1738 // have enough information to make sure that PrevDecl is actually 1739 // the declaration we want to match. For example, given: 1740 // 1741 // class X { 1742 // void f(); 1743 // void f(float); 1744 // }; 1745 // 1746 // void X::f(int) { } // ill-formed 1747 // 1748 // In this case, PrevDecl will point to the overload set 1749 // containing the two f's declared in X, but neither of them 1750 // matches. 1751 1752 // First check whether we named the global scope. 1753 if (isa<TranslationUnitDecl>(DC)) { 1754 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1755 << Name << D.getCXXScopeSpec().getRange(); 1756 } else if (!CurContext->Encloses(DC)) { 1757 // The qualifying scope doesn't enclose the original declaration. 1758 // Emit diagnostic based on current scope. 1759 SourceLocation L = D.getIdentifierLoc(); 1760 SourceRange R = D.getCXXScopeSpec().getRange(); 1761 if (isa<FunctionDecl>(CurContext)) 1762 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1763 else 1764 Diag(L, diag::err_invalid_declarator_scope) 1765 << Name << cast<NamedDecl>(DC) << R; 1766 D.setInvalidType(); 1767 } 1768 } 1769 1770 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1771 // Maybe we will complain about the shadowed template parameter. 1772 if (!D.isInvalidType()) 1773 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1774 D.setInvalidType(); 1775 1776 // Just pretend that we didn't see the previous declaration. 1777 PrevDecl = 0; 1778 } 1779 1780 // In C++, the previous declaration we find might be a tag type 1781 // (class or enum). In this case, the new declaration will hide the 1782 // tag type. Note that this does does not apply if we're declaring a 1783 // typedef (C++ [dcl.typedef]p4). 1784 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1785 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1786 PrevDecl = 0; 1787 1788 bool Redeclaration = false; 1789 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1790 if (TemplateParamLists.size()) { 1791 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1792 return DeclPtrTy(); 1793 } 1794 1795 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1796 } else if (R->isFunctionType()) { 1797 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1798 move(TemplateParamLists), 1799 IsFunctionDefinition, Redeclaration); 1800 } else { 1801 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1802 move(TemplateParamLists), 1803 Redeclaration); 1804 } 1805 1806 if (New == 0) 1807 return DeclPtrTy(); 1808 1809 // If this has an identifier and is not an invalid redeclaration, 1810 // add it to the scope stack. 1811 if (Name && !(Redeclaration && New->isInvalidDecl())) 1812 PushOnScopeChains(New, S); 1813 1814 return DeclPtrTy::make(New); 1815} 1816 1817/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1818/// types into constant array types in certain situations which would otherwise 1819/// be errors (for GCC compatibility). 1820static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1821 ASTContext &Context, 1822 bool &SizeIsNegative) { 1823 // This method tries to turn a variable array into a constant 1824 // array even when the size isn't an ICE. This is necessary 1825 // for compatibility with code that depends on gcc's buggy 1826 // constant expression folding, like struct {char x[(int)(char*)2];} 1827 SizeIsNegative = false; 1828 1829 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1830 QualType Pointee = PTy->getPointeeType(); 1831 QualType FixedType = 1832 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1833 if (FixedType.isNull()) return FixedType; 1834 FixedType = Context.getPointerType(FixedType); 1835 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1836 return FixedType; 1837 } 1838 1839 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1840 if (!VLATy) 1841 return QualType(); 1842 // FIXME: We should probably handle this case 1843 if (VLATy->getElementType()->isVariablyModifiedType()) 1844 return QualType(); 1845 1846 Expr::EvalResult EvalResult; 1847 if (!VLATy->getSizeExpr() || 1848 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1849 !EvalResult.Val.isInt()) 1850 return QualType(); 1851 1852 llvm::APSInt &Res = EvalResult.Val.getInt(); 1853 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1854 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1855 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1856 // so as to transfer ownership to the ConstantArrayWithExpr. 1857 // Alternatively, we could "clone" it (how?). 1858 // Since we don't know how to do things above, we just use the 1859 // very same Expr*. 1860 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1861 Res, ArySizeExpr, 1862 ArrayType::Normal, 0, 1863 VLATy->getBracketsRange()); 1864 } 1865 1866 SizeIsNegative = true; 1867 return QualType(); 1868} 1869 1870/// \brief Register the given locally-scoped external C declaration so 1871/// that it can be found later for redeclarations 1872void 1873Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1874 Scope *S) { 1875 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1876 "Decl is not a locally-scoped decl!"); 1877 // Note that we have a locally-scoped external with this name. 1878 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1879 1880 if (!PrevDecl) 1881 return; 1882 1883 // If there was a previous declaration of this variable, it may be 1884 // in our identifier chain. Update the identifier chain with the new 1885 // declaration. 1886 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1887 // The previous declaration was found on the identifer resolver 1888 // chain, so remove it from its scope. 1889 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1890 S = S->getParent(); 1891 1892 if (S) 1893 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1894 } 1895} 1896 1897/// \brief Diagnose function specifiers on a declaration of an identifier that 1898/// does not identify a function. 1899void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1900 // FIXME: We should probably indicate the identifier in question to avoid 1901 // confusion for constructs like "inline int a(), b;" 1902 if (D.getDeclSpec().isInlineSpecified()) 1903 Diag(D.getDeclSpec().getInlineSpecLoc(), 1904 diag::err_inline_non_function); 1905 1906 if (D.getDeclSpec().isVirtualSpecified()) 1907 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1908 diag::err_virtual_non_function); 1909 1910 if (D.getDeclSpec().isExplicitSpecified()) 1911 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1912 diag::err_explicit_non_function); 1913} 1914 1915NamedDecl* 1916Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1917 QualType R, DeclaratorInfo *DInfo, 1918 Decl* PrevDecl, bool &Redeclaration) { 1919 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1920 if (D.getCXXScopeSpec().isSet()) { 1921 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1922 << D.getCXXScopeSpec().getRange(); 1923 D.setInvalidType(); 1924 // Pretend we didn't see the scope specifier. 1925 DC = 0; 1926 } 1927 1928 if (getLangOptions().CPlusPlus) { 1929 // Check that there are no default arguments (C++ only). 1930 CheckExtraCXXDefaultArguments(D); 1931 } 1932 1933 DiagnoseFunctionSpecifiers(D); 1934 1935 if (D.getDeclSpec().isThreadSpecified()) 1936 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1937 1938 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1939 if (!NewTD) return 0; 1940 1941 if (D.isInvalidType()) 1942 NewTD->setInvalidDecl(); 1943 1944 // Handle attributes prior to checking for duplicates in MergeVarDecl 1945 ProcessDeclAttributes(S, NewTD, D); 1946 // Merge the decl with the existing one if appropriate. If the decl is 1947 // in an outer scope, it isn't the same thing. 1948 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1949 Redeclaration = true; 1950 MergeTypeDefDecl(NewTD, PrevDecl); 1951 } 1952 1953 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1954 // then it shall have block scope. 1955 QualType T = NewTD->getUnderlyingType(); 1956 if (T->isVariablyModifiedType()) { 1957 CurFunctionNeedsScopeChecking = true; 1958 1959 if (S->getFnParent() == 0) { 1960 bool SizeIsNegative; 1961 QualType FixedTy = 1962 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1963 if (!FixedTy.isNull()) { 1964 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1965 NewTD->setUnderlyingType(FixedTy); 1966 } else { 1967 if (SizeIsNegative) 1968 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1969 else if (T->isVariableArrayType()) 1970 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1971 else 1972 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1973 NewTD->setInvalidDecl(); 1974 } 1975 } 1976 } 1977 1978 // If this is the C FILE type, notify the AST context. 1979 if (IdentifierInfo *II = NewTD->getIdentifier()) 1980 if (!NewTD->isInvalidDecl() && 1981 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1982 if (II->isStr("FILE")) 1983 Context.setFILEDecl(NewTD); 1984 else if (II->isStr("jmp_buf")) 1985 Context.setjmp_bufDecl(NewTD); 1986 else if (II->isStr("sigjmp_buf")) 1987 Context.setsigjmp_bufDecl(NewTD); 1988 } 1989 1990 return NewTD; 1991} 1992 1993/// \brief Determines whether the given declaration is an out-of-scope 1994/// previous declaration. 1995/// 1996/// This routine should be invoked when name lookup has found a 1997/// previous declaration (PrevDecl) that is not in the scope where a 1998/// new declaration by the same name is being introduced. If the new 1999/// declaration occurs in a local scope, previous declarations with 2000/// linkage may still be considered previous declarations (C99 2001/// 6.2.2p4-5, C++ [basic.link]p6). 2002/// 2003/// \param PrevDecl the previous declaration found by name 2004/// lookup 2005/// 2006/// \param DC the context in which the new declaration is being 2007/// declared. 2008/// 2009/// \returns true if PrevDecl is an out-of-scope previous declaration 2010/// for a new delcaration with the same name. 2011static bool 2012isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2013 ASTContext &Context) { 2014 if (!PrevDecl) 2015 return 0; 2016 2017 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2018 // case we need to check each of the overloaded functions. 2019 if (!PrevDecl->hasLinkage()) 2020 return false; 2021 2022 if (Context.getLangOptions().CPlusPlus) { 2023 // C++ [basic.link]p6: 2024 // If there is a visible declaration of an entity with linkage 2025 // having the same name and type, ignoring entities declared 2026 // outside the innermost enclosing namespace scope, the block 2027 // scope declaration declares that same entity and receives the 2028 // linkage of the previous declaration. 2029 DeclContext *OuterContext = DC->getLookupContext(); 2030 if (!OuterContext->isFunctionOrMethod()) 2031 // This rule only applies to block-scope declarations. 2032 return false; 2033 else { 2034 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2035 if (PrevOuterContext->isRecord()) 2036 // We found a member function: ignore it. 2037 return false; 2038 else { 2039 // Find the innermost enclosing namespace for the new and 2040 // previous declarations. 2041 while (!OuterContext->isFileContext()) 2042 OuterContext = OuterContext->getParent(); 2043 while (!PrevOuterContext->isFileContext()) 2044 PrevOuterContext = PrevOuterContext->getParent(); 2045 2046 // The previous declaration is in a different namespace, so it 2047 // isn't the same function. 2048 if (OuterContext->getPrimaryContext() != 2049 PrevOuterContext->getPrimaryContext()) 2050 return false; 2051 } 2052 } 2053 } 2054 2055 return true; 2056} 2057 2058NamedDecl* 2059Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2060 QualType R, DeclaratorInfo *DInfo, 2061 NamedDecl* PrevDecl, 2062 MultiTemplateParamsArg TemplateParamLists, 2063 bool &Redeclaration) { 2064 DeclarationName Name = GetNameForDeclarator(D); 2065 2066 // Check that there are no default arguments (C++ only). 2067 if (getLangOptions().CPlusPlus) 2068 CheckExtraCXXDefaultArguments(D); 2069 2070 VarDecl *NewVD; 2071 VarDecl::StorageClass SC; 2072 switch (D.getDeclSpec().getStorageClassSpec()) { 2073 default: assert(0 && "Unknown storage class!"); 2074 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2075 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2076 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2077 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2078 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2079 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2080 case DeclSpec::SCS_mutable: 2081 // mutable can only appear on non-static class members, so it's always 2082 // an error here 2083 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2084 D.setInvalidType(); 2085 SC = VarDecl::None; 2086 break; 2087 } 2088 2089 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2090 if (!II) { 2091 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2092 << Name.getAsString(); 2093 return 0; 2094 } 2095 2096 DiagnoseFunctionSpecifiers(D); 2097 2098 if (!DC->isRecord() && S->getFnParent() == 0) { 2099 // C99 6.9p2: The storage-class specifiers auto and register shall not 2100 // appear in the declaration specifiers in an external declaration. 2101 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2102 2103 // If this is a register variable with an asm label specified, then this 2104 // is a GNU extension. 2105 if (SC == VarDecl::Register && D.getAsmLabel()) 2106 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2107 else 2108 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2109 D.setInvalidType(); 2110 } 2111 } 2112 if (DC->isRecord() && !CurContext->isRecord()) { 2113 // This is an out-of-line definition of a static data member. 2114 if (SC == VarDecl::Static) { 2115 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2116 diag::err_static_out_of_line) 2117 << CodeModificationHint::CreateRemoval( 2118 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2119 } else if (SC == VarDecl::None) 2120 SC = VarDecl::Static; 2121 } 2122 if (SC == VarDecl::Static) { 2123 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2124 if (RD->isLocalClass()) 2125 Diag(D.getIdentifierLoc(), 2126 diag::err_static_data_member_not_allowed_in_local_class) 2127 << Name << RD->getDeclName(); 2128 } 2129 } 2130 2131 // Match up the template parameter lists with the scope specifier, then 2132 // determine whether we have a template or a template specialization. 2133 if (TemplateParameterList *TemplateParams 2134 = MatchTemplateParametersToScopeSpecifier( 2135 D.getDeclSpec().getSourceRange().getBegin(), 2136 D.getCXXScopeSpec(), 2137 (TemplateParameterList**)TemplateParamLists.get(), 2138 TemplateParamLists.size())) { 2139 if (TemplateParams->size() > 0) { 2140 // There is no such thing as a variable template. 2141 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2142 << II 2143 << SourceRange(TemplateParams->getTemplateLoc(), 2144 TemplateParams->getRAngleLoc()); 2145 return 0; 2146 } else { 2147 // There is an extraneous 'template<>' for this variable. Complain 2148 // about it, but allow the declaration of the variable. 2149 Diag(TemplateParams->getTemplateLoc(), 2150 diag::err_template_variable_noparams) 2151 << II 2152 << SourceRange(TemplateParams->getTemplateLoc(), 2153 TemplateParams->getRAngleLoc()); 2154 } 2155 } 2156 2157 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2158 II, R, DInfo, SC); 2159 2160 if (D.isInvalidType()) 2161 NewVD->setInvalidDecl(); 2162 2163 if (D.getDeclSpec().isThreadSpecified()) { 2164 if (NewVD->hasLocalStorage()) 2165 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2166 else if (!Context.Target.isTLSSupported()) 2167 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2168 else 2169 NewVD->setThreadSpecified(true); 2170 } 2171 2172 // Set the lexical context. If the declarator has a C++ scope specifier, the 2173 // lexical context will be different from the semantic context. 2174 NewVD->setLexicalDeclContext(CurContext); 2175 2176 // Handle attributes prior to checking for duplicates in MergeVarDecl 2177 ProcessDeclAttributes(S, NewVD, D); 2178 2179 // Handle GNU asm-label extension (encoded as an attribute). 2180 if (Expr *E = (Expr*) D.getAsmLabel()) { 2181 // The parser guarantees this is a string. 2182 StringLiteral *SE = cast<StringLiteral>(E); 2183 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2184 SE->getByteLength()))); 2185 } 2186 2187 // If name lookup finds a previous declaration that is not in the 2188 // same scope as the new declaration, this may still be an 2189 // acceptable redeclaration. 2190 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2191 !(NewVD->hasLinkage() && 2192 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2193 PrevDecl = 0; 2194 2195 // Merge the decl with the existing one if appropriate. 2196 if (PrevDecl) { 2197 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2198 // The user tried to define a non-static data member 2199 // out-of-line (C++ [dcl.meaning]p1). 2200 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2201 << D.getCXXScopeSpec().getRange(); 2202 PrevDecl = 0; 2203 NewVD->setInvalidDecl(); 2204 } 2205 } else if (D.getCXXScopeSpec().isSet()) { 2206 // No previous declaration in the qualifying scope. 2207 NestedNameSpecifier *NNS = 2208 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2209 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2210 D.getCXXScopeSpec().getRange()); 2211 NewVD->setInvalidDecl(); 2212 } 2213 2214 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2215 2216 // attributes declared post-definition are currently ignored 2217 if (PrevDecl) { 2218 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2219 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2220 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2221 Diag(Def->getLocation(), diag::note_previous_definition); 2222 } 2223 } 2224 2225 // If this is a locally-scoped extern C variable, update the map of 2226 // such variables. 2227 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2228 !NewVD->isInvalidDecl()) 2229 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2230 2231 return NewVD; 2232} 2233 2234/// \brief Perform semantic checking on a newly-created variable 2235/// declaration. 2236/// 2237/// This routine performs all of the type-checking required for a 2238/// variable declaration once it has been built. It is used both to 2239/// check variables after they have been parsed and their declarators 2240/// have been translated into a declaration, and to check variables 2241/// that have been instantiated from a template. 2242/// 2243/// Sets NewVD->isInvalidDecl() if an error was encountered. 2244void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2245 bool &Redeclaration) { 2246 // If the decl is already known invalid, don't check it. 2247 if (NewVD->isInvalidDecl()) 2248 return; 2249 2250 QualType T = NewVD->getType(); 2251 2252 if (T->isObjCInterfaceType()) { 2253 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2254 return NewVD->setInvalidDecl(); 2255 } 2256 2257 // The variable can not have an abstract class type. 2258 if (RequireNonAbstractType(NewVD->getLocation(), T, 2259 diag::err_abstract_type_in_decl, 2260 AbstractVariableType)) 2261 return NewVD->setInvalidDecl(); 2262 2263 // Emit an error if an address space was applied to decl with local storage. 2264 // This includes arrays of objects with address space qualifiers, but not 2265 // automatic variables that point to other address spaces. 2266 // ISO/IEC TR 18037 S5.1.2 2267 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2268 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2269 return NewVD->setInvalidDecl(); 2270 } 2271 2272 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2273 && !NewVD->hasAttr<BlocksAttr>()) 2274 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2275 2276 bool isVM = T->isVariablyModifiedType(); 2277 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2278 NewVD->hasAttr<BlocksAttr>()) 2279 CurFunctionNeedsScopeChecking = true; 2280 2281 if ((isVM && NewVD->hasLinkage()) || 2282 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2283 bool SizeIsNegative; 2284 QualType FixedTy = 2285 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2286 2287 if (FixedTy.isNull() && T->isVariableArrayType()) { 2288 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2289 // FIXME: This won't give the correct result for 2290 // int a[10][n]; 2291 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2292 2293 if (NewVD->isFileVarDecl()) 2294 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2295 << SizeRange; 2296 else if (NewVD->getStorageClass() == VarDecl::Static) 2297 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2298 << SizeRange; 2299 else 2300 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2301 << SizeRange; 2302 return NewVD->setInvalidDecl(); 2303 } 2304 2305 if (FixedTy.isNull()) { 2306 if (NewVD->isFileVarDecl()) 2307 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2308 else 2309 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2310 return NewVD->setInvalidDecl(); 2311 } 2312 2313 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2314 NewVD->setType(FixedTy); 2315 } 2316 2317 if (!PrevDecl && NewVD->isExternC()) { 2318 // Since we did not find anything by this name and we're declaring 2319 // an extern "C" variable, look for a non-visible extern "C" 2320 // declaration with the same name. 2321 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2322 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2323 if (Pos != LocallyScopedExternalDecls.end()) 2324 PrevDecl = Pos->second; 2325 } 2326 2327 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2328 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2329 << T; 2330 return NewVD->setInvalidDecl(); 2331 } 2332 2333 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2334 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2335 return NewVD->setInvalidDecl(); 2336 } 2337 2338 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2339 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2340 return NewVD->setInvalidDecl(); 2341 } 2342 2343 if (PrevDecl) { 2344 Redeclaration = true; 2345 MergeVarDecl(NewVD, PrevDecl); 2346 } 2347} 2348 2349static bool isUsingDecl(Decl *D) { 2350 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2351} 2352 2353NamedDecl* 2354Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2355 QualType R, DeclaratorInfo *DInfo, 2356 NamedDecl* PrevDecl, 2357 MultiTemplateParamsArg TemplateParamLists, 2358 bool IsFunctionDefinition, bool &Redeclaration) { 2359 assert(R.getTypePtr()->isFunctionType()); 2360 2361 DeclarationName Name = GetNameForDeclarator(D); 2362 FunctionDecl::StorageClass SC = FunctionDecl::None; 2363 switch (D.getDeclSpec().getStorageClassSpec()) { 2364 default: assert(0 && "Unknown storage class!"); 2365 case DeclSpec::SCS_auto: 2366 case DeclSpec::SCS_register: 2367 case DeclSpec::SCS_mutable: 2368 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2369 diag::err_typecheck_sclass_func); 2370 D.setInvalidType(); 2371 break; 2372 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2373 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2374 case DeclSpec::SCS_static: { 2375 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2376 // C99 6.7.1p5: 2377 // The declaration of an identifier for a function that has 2378 // block scope shall have no explicit storage-class specifier 2379 // other than extern 2380 // See also (C++ [dcl.stc]p4). 2381 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2382 diag::err_static_block_func); 2383 SC = FunctionDecl::None; 2384 } else 2385 SC = FunctionDecl::Static; 2386 break; 2387 } 2388 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2389 } 2390 2391 if (D.getDeclSpec().isThreadSpecified()) 2392 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2393 2394 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2395 bool isInline = D.getDeclSpec().isInlineSpecified(); 2396 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2397 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2398 2399 // Check that the return type is not an abstract class type. 2400 // For record types, this is done by the AbstractClassUsageDiagnoser once 2401 // the class has been completely parsed. 2402 if (!DC->isRecord() && 2403 RequireNonAbstractType(D.getIdentifierLoc(), 2404 R->getAsFunctionType()->getResultType(), 2405 diag::err_abstract_type_in_decl, 2406 AbstractReturnType)) 2407 D.setInvalidType(); 2408 2409 // Do not allow returning a objc interface by-value. 2410 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2411 Diag(D.getIdentifierLoc(), 2412 diag::err_object_cannot_be_passed_returned_by_value) << 0 2413 << R->getAsFunctionType()->getResultType(); 2414 D.setInvalidType(); 2415 } 2416 2417 bool isVirtualOkay = false; 2418 FunctionDecl *NewFD; 2419 2420 if (isFriend) { 2421 // DC is the namespace in which the function is being declared. 2422 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2423 "friend function being created in a non-namespace context"); 2424 2425 // C++ [class.friend]p5 2426 // A function can be defined in a friend declaration of a 2427 // class . . . . Such a function is implicitly inline. 2428 isInline |= IsFunctionDefinition; 2429 } 2430 2431 if (D.getKind() == Declarator::DK_Constructor) { 2432 // This is a C++ constructor declaration. 2433 assert(DC->isRecord() && 2434 "Constructors can only be declared in a member context"); 2435 2436 R = CheckConstructorDeclarator(D, R, SC); 2437 2438 // Create the new declaration 2439 NewFD = CXXConstructorDecl::Create(Context, 2440 cast<CXXRecordDecl>(DC), 2441 D.getIdentifierLoc(), Name, R, DInfo, 2442 isExplicit, isInline, 2443 /*isImplicitlyDeclared=*/false); 2444 } else if (D.getKind() == Declarator::DK_Destructor) { 2445 // This is a C++ destructor declaration. 2446 if (DC->isRecord()) { 2447 R = CheckDestructorDeclarator(D, SC); 2448 2449 NewFD = CXXDestructorDecl::Create(Context, 2450 cast<CXXRecordDecl>(DC), 2451 D.getIdentifierLoc(), Name, R, 2452 isInline, 2453 /*isImplicitlyDeclared=*/false); 2454 2455 isVirtualOkay = true; 2456 } else { 2457 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2458 2459 // Create a FunctionDecl to satisfy the function definition parsing 2460 // code path. 2461 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2462 Name, R, DInfo, SC, isInline, 2463 /*hasPrototype=*/true); 2464 D.setInvalidType(); 2465 } 2466 } else if (D.getKind() == Declarator::DK_Conversion) { 2467 if (!DC->isRecord()) { 2468 Diag(D.getIdentifierLoc(), 2469 diag::err_conv_function_not_member); 2470 return 0; 2471 } 2472 2473 CheckConversionDeclarator(D, R, SC); 2474 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2475 D.getIdentifierLoc(), Name, R, DInfo, 2476 isInline, isExplicit); 2477 2478 isVirtualOkay = true; 2479 } else if (DC->isRecord()) { 2480 // If the of the function is the same as the name of the record, then this 2481 // must be an invalid constructor that has a return type. 2482 // (The parser checks for a return type and makes the declarator a 2483 // constructor if it has no return type). 2484 // must have an invalid constructor that has a return type 2485 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2486 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2487 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2488 << SourceRange(D.getIdentifierLoc()); 2489 return 0; 2490 } 2491 2492 // This is a C++ method declaration. 2493 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2494 D.getIdentifierLoc(), Name, R, DInfo, 2495 (SC == FunctionDecl::Static), isInline); 2496 2497 isVirtualOkay = (SC != FunctionDecl::Static); 2498 } else { 2499 // Determine whether the function was written with a 2500 // prototype. This true when: 2501 // - we're in C++ (where every function has a prototype), 2502 // - there is a prototype in the declarator, or 2503 // - the type R of the function is some kind of typedef or other reference 2504 // to a type name (which eventually refers to a function type). 2505 bool HasPrototype = 2506 getLangOptions().CPlusPlus || 2507 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2508 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2509 2510 NewFD = FunctionDecl::Create(Context, DC, 2511 D.getIdentifierLoc(), 2512 Name, R, DInfo, SC, isInline, HasPrototype); 2513 } 2514 2515 if (D.isInvalidType()) 2516 NewFD->setInvalidDecl(); 2517 2518 // Set the lexical context. If the declarator has a C++ 2519 // scope specifier, or is the object of a friend declaration, the 2520 // lexical context will be different from the semantic context. 2521 NewFD->setLexicalDeclContext(CurContext); 2522 2523 if (isFriend) 2524 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2525 2526 // Match up the template parameter lists with the scope specifier, then 2527 // determine whether we have a template or a template specialization. 2528 FunctionTemplateDecl *FunctionTemplate = 0; 2529 if (TemplateParameterList *TemplateParams 2530 = MatchTemplateParametersToScopeSpecifier( 2531 D.getDeclSpec().getSourceRange().getBegin(), 2532 D.getCXXScopeSpec(), 2533 (TemplateParameterList**)TemplateParamLists.get(), 2534 TemplateParamLists.size())) { 2535 if (TemplateParams->size() > 0) { 2536 // This is a function template 2537 2538 // Check that we can declare a template here. 2539 if (CheckTemplateDeclScope(S, TemplateParams)) 2540 return 0; 2541 2542 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2543 NewFD->getLocation(), 2544 Name, TemplateParams, 2545 NewFD); 2546 FunctionTemplate->setLexicalDeclContext(CurContext); 2547 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2548 } else { 2549 // FIXME: Handle function template specializations 2550 } 2551 2552 // FIXME: Free this memory properly. 2553 TemplateParamLists.release(); 2554 } 2555 2556 // C++ [dcl.fct.spec]p5: 2557 // The virtual specifier shall only be used in declarations of 2558 // nonstatic class member functions that appear within a 2559 // member-specification of a class declaration; see 10.3. 2560 // 2561 if (isVirtual && !NewFD->isInvalidDecl()) { 2562 if (!isVirtualOkay) { 2563 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2564 diag::err_virtual_non_function); 2565 } else if (!CurContext->isRecord()) { 2566 // 'virtual' was specified outside of the class. 2567 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2568 << CodeModificationHint::CreateRemoval( 2569 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2570 } else { 2571 // Okay: Add virtual to the method. 2572 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2573 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2574 CurClass->setAggregate(false); 2575 CurClass->setPOD(false); 2576 CurClass->setEmpty(false); 2577 CurClass->setPolymorphic(true); 2578 CurClass->setHasTrivialConstructor(false); 2579 CurClass->setHasTrivialCopyConstructor(false); 2580 CurClass->setHasTrivialCopyAssignment(false); 2581 } 2582 } 2583 2584 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2585 // Look for virtual methods in base classes that this method might override. 2586 2587 BasePaths Paths; 2588 if (LookupInBases(cast<CXXRecordDecl>(DC), 2589 MemberLookupCriteria(NewMD), Paths)) { 2590 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2591 E = Paths.found_decls_end(); I != E; ++I) { 2592 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2593 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2594 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2595 NewMD->addOverriddenMethod(OldMD); 2596 } 2597 } 2598 } 2599 } 2600 2601 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2602 !CurContext->isRecord()) { 2603 // C++ [class.static]p1: 2604 // A data or function member of a class may be declared static 2605 // in a class definition, in which case it is a static member of 2606 // the class. 2607 2608 // Complain about the 'static' specifier if it's on an out-of-line 2609 // member function definition. 2610 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2611 diag::err_static_out_of_line) 2612 << CodeModificationHint::CreateRemoval( 2613 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2614 } 2615 2616 // Handle GNU asm-label extension (encoded as an attribute). 2617 if (Expr *E = (Expr*) D.getAsmLabel()) { 2618 // The parser guarantees this is a string. 2619 StringLiteral *SE = cast<StringLiteral>(E); 2620 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2621 SE->getByteLength()))); 2622 } 2623 2624 // Copy the parameter declarations from the declarator D to the function 2625 // declaration NewFD, if they are available. First scavenge them into Params. 2626 llvm::SmallVector<ParmVarDecl*, 16> Params; 2627 if (D.getNumTypeObjects() > 0) { 2628 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2629 2630 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2631 // function that takes no arguments, not a function that takes a 2632 // single void argument. 2633 // We let through "const void" here because Sema::GetTypeForDeclarator 2634 // already checks for that case. 2635 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2636 FTI.ArgInfo[0].Param && 2637 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2638 // Empty arg list, don't push any params. 2639 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2640 2641 // In C++, the empty parameter-type-list must be spelled "void"; a 2642 // typedef of void is not permitted. 2643 if (getLangOptions().CPlusPlus && 2644 Param->getType().getUnqualifiedType() != Context.VoidTy) 2645 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2646 // FIXME: Leaks decl? 2647 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2648 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2649 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2650 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2651 Param->setDeclContext(NewFD); 2652 Params.push_back(Param); 2653 } 2654 } 2655 2656 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2657 // When we're declaring a function with a typedef, typeof, etc as in the 2658 // following example, we'll need to synthesize (unnamed) 2659 // parameters for use in the declaration. 2660 // 2661 // @code 2662 // typedef void fn(int); 2663 // fn f; 2664 // @endcode 2665 2666 // Synthesize a parameter for each argument type. 2667 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2668 AE = FT->arg_type_end(); AI != AE; ++AI) { 2669 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2670 SourceLocation(), 0, 2671 *AI, /*DInfo=*/0, 2672 VarDecl::None, 0); 2673 Param->setImplicit(); 2674 Params.push_back(Param); 2675 } 2676 } else { 2677 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2678 "Should not need args for typedef of non-prototype fn"); 2679 } 2680 // Finally, we know we have the right number of parameters, install them. 2681 NewFD->setParams(Context, Params.data(), Params.size()); 2682 2683 // If name lookup finds a previous declaration that is not in the 2684 // same scope as the new declaration, this may still be an 2685 // acceptable redeclaration. 2686 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2687 !(NewFD->hasLinkage() && 2688 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2689 PrevDecl = 0; 2690 2691 // Perform semantic checking on the function declaration. 2692 bool OverloadableAttrRequired = false; // FIXME: HACK! 2693 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2694 /*FIXME:*/OverloadableAttrRequired); 2695 2696 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2697 // An out-of-line member function declaration must also be a 2698 // definition (C++ [dcl.meaning]p1). 2699 if (!IsFunctionDefinition && !isFriend) { 2700 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2701 << D.getCXXScopeSpec().getRange(); 2702 NewFD->setInvalidDecl(); 2703 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2704 // The user tried to provide an out-of-line definition for a 2705 // function that is a member of a class or namespace, but there 2706 // was no such member function declared (C++ [class.mfct]p2, 2707 // C++ [namespace.memdef]p2). For example: 2708 // 2709 // class X { 2710 // void f() const; 2711 // }; 2712 // 2713 // void X::f() { } // ill-formed 2714 // 2715 // Complain about this problem, and attempt to suggest close 2716 // matches (e.g., those that differ only in cv-qualifiers and 2717 // whether the parameter types are references). 2718 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2719 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2720 NewFD->setInvalidDecl(); 2721 2722 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2723 true); 2724 assert(!Prev.isAmbiguous() && 2725 "Cannot have an ambiguity in previous-declaration lookup"); 2726 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2727 Func != FuncEnd; ++Func) { 2728 if (isa<FunctionDecl>(*Func) && 2729 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2730 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2731 } 2732 2733 PrevDecl = 0; 2734 } 2735 } 2736 2737 // Handle attributes. We need to have merged decls when handling attributes 2738 // (for example to check for conflicts, etc). 2739 // FIXME: This needs to happen before we merge declarations. Then, 2740 // let attribute merging cope with attribute conflicts. 2741 ProcessDeclAttributes(S, NewFD, D); 2742 2743 // attributes declared post-definition are currently ignored 2744 if (Redeclaration && PrevDecl) { 2745 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2746 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2747 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2748 Diag(Def->getLocation(), diag::note_previous_definition); 2749 } 2750 } 2751 2752 AddKnownFunctionAttributes(NewFD); 2753 2754 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2755 // If a function name is overloadable in C, then every function 2756 // with that name must be marked "overloadable". 2757 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2758 << Redeclaration << NewFD; 2759 if (PrevDecl) 2760 Diag(PrevDecl->getLocation(), 2761 diag::note_attribute_overloadable_prev_overload); 2762 NewFD->addAttr(::new (Context) OverloadableAttr()); 2763 } 2764 2765 // If this is a locally-scoped extern C function, update the 2766 // map of such names. 2767 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2768 && !NewFD->isInvalidDecl()) 2769 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2770 2771 // Set this FunctionDecl's range up to the right paren. 2772 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2773 2774 if (FunctionTemplate && NewFD->isInvalidDecl()) 2775 FunctionTemplate->setInvalidDecl(); 2776 2777 if (FunctionTemplate) 2778 return FunctionTemplate; 2779 2780 return NewFD; 2781} 2782 2783/// \brief Perform semantic checking of a new function declaration. 2784/// 2785/// Performs semantic analysis of the new function declaration 2786/// NewFD. This routine performs all semantic checking that does not 2787/// require the actual declarator involved in the declaration, and is 2788/// used both for the declaration of functions as they are parsed 2789/// (called via ActOnDeclarator) and for the declaration of functions 2790/// that have been instantiated via C++ template instantiation (called 2791/// via InstantiateDecl). 2792/// 2793/// This sets NewFD->isInvalidDecl() to true if there was an error. 2794void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2795 bool &Redeclaration, 2796 bool &OverloadableAttrRequired) { 2797 // If NewFD is already known erroneous, don't do any of this checking. 2798 if (NewFD->isInvalidDecl()) 2799 return; 2800 2801 if (NewFD->getResultType()->isVariablyModifiedType()) { 2802 // Functions returning a variably modified type violate C99 6.7.5.2p2 2803 // because all functions have linkage. 2804 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2805 return NewFD->setInvalidDecl(); 2806 } 2807 2808 if (NewFD->isMain()) 2809 CheckMain(NewFD); 2810 2811 // Check for a previous declaration of this name. 2812 if (!PrevDecl && NewFD->isExternC()) { 2813 // Since we did not find anything by this name and we're declaring 2814 // an extern "C" function, look for a non-visible extern "C" 2815 // declaration with the same name. 2816 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2817 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2818 if (Pos != LocallyScopedExternalDecls.end()) 2819 PrevDecl = Pos->second; 2820 } 2821 2822 // Merge or overload the declaration with an existing declaration of 2823 // the same name, if appropriate. 2824 if (PrevDecl) { 2825 // Determine whether NewFD is an overload of PrevDecl or 2826 // a declaration that requires merging. If it's an overload, 2827 // there's no more work to do here; we'll just add the new 2828 // function to the scope. 2829 OverloadedFunctionDecl::function_iterator MatchedDecl; 2830 2831 if (!getLangOptions().CPlusPlus && 2832 AllowOverloadingOfFunction(PrevDecl, Context)) { 2833 OverloadableAttrRequired = true; 2834 2835 // Functions marked "overloadable" must have a prototype (that 2836 // we can't get through declaration merging). 2837 if (!NewFD->getType()->getAsFunctionProtoType()) { 2838 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2839 << NewFD; 2840 Redeclaration = true; 2841 2842 // Turn this into a variadic function with no parameters. 2843 QualType R = Context.getFunctionType( 2844 NewFD->getType()->getAsFunctionType()->getResultType(), 2845 0, 0, true, 0); 2846 NewFD->setType(R); 2847 return NewFD->setInvalidDecl(); 2848 } 2849 } 2850 2851 if (PrevDecl && 2852 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2853 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2854 Redeclaration = true; 2855 Decl *OldDecl = PrevDecl; 2856 2857 // If PrevDecl was an overloaded function, extract the 2858 // FunctionDecl that matched. 2859 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2860 OldDecl = *MatchedDecl; 2861 2862 // NewFD and OldDecl represent declarations that need to be 2863 // merged. 2864 if (MergeFunctionDecl(NewFD, OldDecl)) 2865 return NewFD->setInvalidDecl(); 2866 2867 if (FunctionTemplateDecl *OldTemplateDecl 2868 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2869 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2870 else { 2871 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2872 NewFD->setAccess(OldDecl->getAccess()); 2873 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2874 } 2875 } 2876 } 2877 2878 // Semantic checking for this function declaration (in isolation). 2879 if (getLangOptions().CPlusPlus) { 2880 // C++-specific checks. 2881 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2882 CheckConstructor(Constructor); 2883 } else if (isa<CXXDestructorDecl>(NewFD)) { 2884 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2885 QualType ClassType = Context.getTypeDeclType(Record); 2886 if (!ClassType->isDependentType()) { 2887 DeclarationName Name 2888 = Context.DeclarationNames.getCXXDestructorName( 2889 Context.getCanonicalType(ClassType)); 2890 if (NewFD->getDeclName() != Name) { 2891 Diag(NewFD->getLocation(), diag::err_destructor_name); 2892 return NewFD->setInvalidDecl(); 2893 } 2894 } 2895 Record->setUserDeclaredDestructor(true); 2896 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2897 // user-defined destructor. 2898 Record->setPOD(false); 2899 2900 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2901 // declared destructor. 2902 // FIXME: C++0x: don't do this for "= default" destructors 2903 Record->setHasTrivialDestructor(false); 2904 } else if (CXXConversionDecl *Conversion 2905 = dyn_cast<CXXConversionDecl>(NewFD)) 2906 ActOnConversionDeclarator(Conversion); 2907 2908 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2909 if (NewFD->isOverloadedOperator() && 2910 CheckOverloadedOperatorDeclaration(NewFD)) 2911 return NewFD->setInvalidDecl(); 2912 2913 // In C++, check default arguments now that we have merged decls. Unless 2914 // the lexical context is the class, because in this case this is done 2915 // during delayed parsing anyway. 2916 if (!CurContext->isRecord()) 2917 CheckCXXDefaultArguments(NewFD); 2918 } 2919} 2920 2921void Sema::CheckMain(FunctionDecl* FD) { 2922 // C++ [basic.start.main]p3: A program that declares main to be inline 2923 // or static is ill-formed. 2924 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2925 // shall not appear in a declaration of main. 2926 // static main is not an error under C99, but we should warn about it. 2927 bool isInline = FD->isInline(); 2928 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2929 if (isInline || isStatic) { 2930 unsigned diagID = diag::warn_unusual_main_decl; 2931 if (isInline || getLangOptions().CPlusPlus) 2932 diagID = diag::err_unusual_main_decl; 2933 2934 int which = isStatic + (isInline << 1) - 1; 2935 Diag(FD->getLocation(), diagID) << which; 2936 } 2937 2938 QualType T = FD->getType(); 2939 assert(T->isFunctionType() && "function decl is not of function type"); 2940 const FunctionType* FT = T->getAsFunctionType(); 2941 2942 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2943 // TODO: add a replacement fixit to turn the return type into 'int'. 2944 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2945 FD->setInvalidDecl(true); 2946 } 2947 2948 // Treat protoless main() as nullary. 2949 if (isa<FunctionNoProtoType>(FT)) return; 2950 2951 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2952 unsigned nparams = FTP->getNumArgs(); 2953 assert(FD->getNumParams() == nparams); 2954 2955 if (nparams > 3) { 2956 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2957 FD->setInvalidDecl(true); 2958 nparams = 3; 2959 } 2960 2961 // FIXME: a lot of the following diagnostics would be improved 2962 // if we had some location information about types. 2963 2964 QualType CharPP = 2965 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2966 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2967 2968 for (unsigned i = 0; i < nparams; ++i) { 2969 QualType AT = FTP->getArgType(i); 2970 2971 bool mismatch = true; 2972 2973 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2974 mismatch = false; 2975 else if (Expected[i] == CharPP) { 2976 // As an extension, the following forms are okay: 2977 // char const ** 2978 // char const * const * 2979 // char * const * 2980 2981 QualifierSet qs; 2982 const PointerType* PT; 2983 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 2984 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 2985 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 2986 qs.removeConst(); 2987 mismatch = !qs.empty(); 2988 } 2989 } 2990 2991 if (mismatch) { 2992 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 2993 // TODO: suggest replacing given type with expected type 2994 FD->setInvalidDecl(true); 2995 } 2996 } 2997 2998 if (nparams == 1 && !FD->isInvalidDecl()) { 2999 Diag(FD->getLocation(), diag::warn_main_one_arg); 3000 } 3001} 3002 3003bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3004 // FIXME: Need strict checking. In C89, we need to check for 3005 // any assignment, increment, decrement, function-calls, or 3006 // commas outside of a sizeof. In C99, it's the same list, 3007 // except that the aforementioned are allowed in unevaluated 3008 // expressions. Everything else falls under the 3009 // "may accept other forms of constant expressions" exception. 3010 // (We never end up here for C++, so the constant expression 3011 // rules there don't matter.) 3012 if (Init->isConstantInitializer(Context)) 3013 return false; 3014 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3015 << Init->getSourceRange(); 3016 return true; 3017} 3018 3019void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3020 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3021} 3022 3023/// AddInitializerToDecl - Adds the initializer Init to the 3024/// declaration dcl. If DirectInit is true, this is C++ direct 3025/// initialization rather than copy initialization. 3026void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3027 Decl *RealDecl = dcl.getAs<Decl>(); 3028 // If there is no declaration, there was an error parsing it. Just ignore 3029 // the initializer. 3030 if (RealDecl == 0) 3031 return; 3032 3033 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3034 // With declarators parsed the way they are, the parser cannot 3035 // distinguish between a normal initializer and a pure-specifier. 3036 // Thus this grotesque test. 3037 IntegerLiteral *IL; 3038 Expr *Init = static_cast<Expr *>(init.get()); 3039 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3040 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3041 if (Method->isVirtualAsWritten()) { 3042 Method->setPure(); 3043 3044 // A class is abstract if at least one function is pure virtual. 3045 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3046 } else if (!Method->isInvalidDecl()) { 3047 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3048 << Method->getDeclName() << Init->getSourceRange(); 3049 Method->setInvalidDecl(); 3050 } 3051 } else { 3052 Diag(Method->getLocation(), diag::err_member_function_initialization) 3053 << Method->getDeclName() << Init->getSourceRange(); 3054 Method->setInvalidDecl(); 3055 } 3056 return; 3057 } 3058 3059 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3060 if (!VDecl) { 3061 if (getLangOptions().CPlusPlus && 3062 RealDecl->getLexicalDeclContext()->isRecord() && 3063 isa<NamedDecl>(RealDecl)) 3064 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3065 << cast<NamedDecl>(RealDecl)->getDeclName(); 3066 else 3067 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3068 RealDecl->setInvalidDecl(); 3069 return; 3070 } 3071 3072 if (!VDecl->getType()->isArrayType() && 3073 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3074 diag::err_typecheck_decl_incomplete_type)) { 3075 RealDecl->setInvalidDecl(); 3076 return; 3077 } 3078 3079 const VarDecl *Def = 0; 3080 if (VDecl->getDefinition(Def)) { 3081 Diag(VDecl->getLocation(), diag::err_redefinition) 3082 << VDecl->getDeclName(); 3083 Diag(Def->getLocation(), diag::note_previous_definition); 3084 VDecl->setInvalidDecl(); 3085 return; 3086 } 3087 3088 // Take ownership of the expression, now that we're sure we have somewhere 3089 // to put it. 3090 Expr *Init = init.takeAs<Expr>(); 3091 assert(Init && "missing initializer"); 3092 3093 // Get the decls type and save a reference for later, since 3094 // CheckInitializerTypes may change it. 3095 QualType DclT = VDecl->getType(), SavT = DclT; 3096 if (VDecl->isBlockVarDecl()) { 3097 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3098 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3099 VDecl->setInvalidDecl(); 3100 } else if (!VDecl->isInvalidDecl()) { 3101 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3102 VDecl->getDeclName(), DirectInit)) 3103 VDecl->setInvalidDecl(); 3104 3105 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3106 // Don't check invalid declarations to avoid emitting useless diagnostics. 3107 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3108 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3109 CheckForConstantInitializer(Init, DclT); 3110 } 3111 } 3112 } else if (VDecl->isStaticDataMember() && 3113 VDecl->getLexicalDeclContext()->isRecord()) { 3114 // This is an in-class initialization for a static data member, e.g., 3115 // 3116 // struct S { 3117 // static const int value = 17; 3118 // }; 3119 3120 // Attach the initializer 3121 VDecl->setInit(Context, Init); 3122 3123 // C++ [class.mem]p4: 3124 // A member-declarator can contain a constant-initializer only 3125 // if it declares a static member (9.4) of const integral or 3126 // const enumeration type, see 9.4.2. 3127 QualType T = VDecl->getType(); 3128 if (!T->isDependentType() && 3129 (!Context.getCanonicalType(T).isConstQualified() || 3130 !T->isIntegralType())) { 3131 Diag(VDecl->getLocation(), diag::err_member_initialization) 3132 << VDecl->getDeclName() << Init->getSourceRange(); 3133 VDecl->setInvalidDecl(); 3134 } else { 3135 // C++ [class.static.data]p4: 3136 // If a static data member is of const integral or const 3137 // enumeration type, its declaration in the class definition 3138 // can specify a constant-initializer which shall be an 3139 // integral constant expression (5.19). 3140 if (!Init->isTypeDependent() && 3141 !Init->getType()->isIntegralType()) { 3142 // We have a non-dependent, non-integral or enumeration type. 3143 Diag(Init->getSourceRange().getBegin(), 3144 diag::err_in_class_initializer_non_integral_type) 3145 << Init->getType() << Init->getSourceRange(); 3146 VDecl->setInvalidDecl(); 3147 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3148 // Check whether the expression is a constant expression. 3149 llvm::APSInt Value; 3150 SourceLocation Loc; 3151 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3152 Diag(Loc, diag::err_in_class_initializer_non_constant) 3153 << Init->getSourceRange(); 3154 VDecl->setInvalidDecl(); 3155 } else if (!VDecl->getType()->isDependentType()) 3156 ImpCastExprToType(Init, VDecl->getType()); 3157 } 3158 } 3159 } else if (VDecl->isFileVarDecl()) { 3160 if (VDecl->getStorageClass() == VarDecl::Extern) 3161 Diag(VDecl->getLocation(), diag::warn_extern_init); 3162 if (!VDecl->isInvalidDecl()) 3163 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3164 VDecl->getDeclName(), DirectInit)) 3165 VDecl->setInvalidDecl(); 3166 3167 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3168 // Don't check invalid declarations to avoid emitting useless diagnostics. 3169 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3170 // C99 6.7.8p4. All file scoped initializers need to be constant. 3171 CheckForConstantInitializer(Init, DclT); 3172 } 3173 } 3174 // If the type changed, it means we had an incomplete type that was 3175 // completed by the initializer. For example: 3176 // int ary[] = { 1, 3, 5 }; 3177 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3178 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3179 VDecl->setType(DclT); 3180 Init->setType(DclT); 3181 } 3182 3183 Init = MaybeCreateCXXExprWithTemporaries(Init, 3184 /*ShouldDestroyTemporaries=*/true); 3185 // Attach the initializer to the decl. 3186 VDecl->setInit(Context, Init); 3187 3188 // If the previous declaration of VDecl was a tentative definition, 3189 // remove it from the set of tentative definitions. 3190 if (VDecl->getPreviousDeclaration() && 3191 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3192 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3193 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3194 } 3195 3196 return; 3197} 3198 3199void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3200 bool TypeContainsUndeducedAuto) { 3201 Decl *RealDecl = dcl.getAs<Decl>(); 3202 3203 // If there is no declaration, there was an error parsing it. Just ignore it. 3204 if (RealDecl == 0) 3205 return; 3206 3207 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3208 QualType Type = Var->getType(); 3209 3210 // Record tentative definitions. 3211 if (Var->isTentativeDefinition(Context)) { 3212 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3213 InsertPair = 3214 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3215 3216 // Keep the latest definition in the map. If we see 'int i; int i;' we 3217 // want the second one in the map. 3218 InsertPair.first->second = Var; 3219 3220 // However, for the list, we don't care about the order, just make sure 3221 // that there are no dupes for a given declaration name. 3222 if (InsertPair.second) 3223 TentativeDefinitionList.push_back(Var->getDeclName()); 3224 } 3225 3226 // C++ [dcl.init.ref]p3: 3227 // The initializer can be omitted for a reference only in a 3228 // parameter declaration (8.3.5), in the declaration of a 3229 // function return type, in the declaration of a class member 3230 // within its class declaration (9.2), and where the extern 3231 // specifier is explicitly used. 3232 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3233 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3234 << Var->getDeclName() 3235 << SourceRange(Var->getLocation(), Var->getLocation()); 3236 Var->setInvalidDecl(); 3237 return; 3238 } 3239 3240 // C++0x [dcl.spec.auto]p3 3241 if (TypeContainsUndeducedAuto) { 3242 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3243 << Var->getDeclName() << Type; 3244 Var->setInvalidDecl(); 3245 return; 3246 } 3247 3248 // C++ [dcl.init]p9: 3249 // If no initializer is specified for an object, and the object 3250 // is of (possibly cv-qualified) non-POD class type (or array 3251 // thereof), the object shall be default-initialized; if the 3252 // object is of const-qualified type, the underlying class type 3253 // shall have a user-declared default constructor. 3254 // 3255 // FIXME: Diagnose the "user-declared default constructor" bit. 3256 if (getLangOptions().CPlusPlus) { 3257 QualType InitType = Type; 3258 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3259 InitType = Array->getElementType(); 3260 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3261 InitType->isRecordType() && !InitType->isDependentType()) { 3262 if (!RequireCompleteType(Var->getLocation(), InitType, 3263 diag::err_invalid_incomplete_type_use)) { 3264 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3265 3266 CXXConstructorDecl *Constructor 3267 = PerformInitializationByConstructor(InitType, 3268 MultiExprArg(*this, 0, 0), 3269 Var->getLocation(), 3270 SourceRange(Var->getLocation(), 3271 Var->getLocation()), 3272 Var->getDeclName(), 3273 IK_Default, 3274 ConstructorArgs); 3275 3276 // FIXME: Location info for the variable initialization? 3277 if (!Constructor) 3278 Var->setInvalidDecl(); 3279 else { 3280 // FIXME: Cope with initialization of arrays 3281 if (!Constructor->isTrivial() && 3282 InitializeVarWithConstructor(Var, Constructor, InitType, 3283 move_arg(ConstructorArgs))) 3284 Var->setInvalidDecl(); 3285 3286 FinalizeVarWithDestructor(Var, InitType); 3287 } 3288 } 3289 } 3290 } 3291 3292#if 0 3293 // FIXME: Temporarily disabled because we are not properly parsing 3294 // linkage specifications on declarations, e.g., 3295 // 3296 // extern "C" const CGPoint CGPointerZero; 3297 // 3298 // C++ [dcl.init]p9: 3299 // 3300 // If no initializer is specified for an object, and the 3301 // object is of (possibly cv-qualified) non-POD class type (or 3302 // array thereof), the object shall be default-initialized; if 3303 // the object is of const-qualified type, the underlying class 3304 // type shall have a user-declared default 3305 // constructor. Otherwise, if no initializer is specified for 3306 // an object, the object and its subobjects, if any, have an 3307 // indeterminate initial value; if the object or any of its 3308 // subobjects are of const-qualified type, the program is 3309 // ill-formed. 3310 // 3311 // This isn't technically an error in C, so we don't diagnose it. 3312 // 3313 // FIXME: Actually perform the POD/user-defined default 3314 // constructor check. 3315 if (getLangOptions().CPlusPlus && 3316 Context.getCanonicalType(Type).isConstQualified() && 3317 !Var->hasExternalStorage()) 3318 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3319 << Var->getName() 3320 << SourceRange(Var->getLocation(), Var->getLocation()); 3321#endif 3322 } 3323} 3324 3325Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3326 DeclPtrTy *Group, 3327 unsigned NumDecls) { 3328 llvm::SmallVector<Decl*, 8> Decls; 3329 3330 if (DS.isTypeSpecOwned()) 3331 Decls.push_back((Decl*)DS.getTypeRep()); 3332 3333 for (unsigned i = 0; i != NumDecls; ++i) 3334 if (Decl *D = Group[i].getAs<Decl>()) 3335 Decls.push_back(D); 3336 3337 // Perform semantic analysis that depends on having fully processed both 3338 // the declarator and initializer. 3339 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3340 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3341 if (!IDecl) 3342 continue; 3343 QualType T = IDecl->getType(); 3344 3345 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3346 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3347 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3348 if (!IDecl->isInvalidDecl() && 3349 RequireCompleteType(IDecl->getLocation(), T, 3350 diag::err_typecheck_decl_incomplete_type)) 3351 IDecl->setInvalidDecl(); 3352 } 3353 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3354 // object that has file scope without an initializer, and without a 3355 // storage-class specifier or with the storage-class specifier "static", 3356 // constitutes a tentative definition. Note: A tentative definition with 3357 // external linkage is valid (C99 6.2.2p5). 3358 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3359 if (const IncompleteArrayType *ArrayT 3360 = Context.getAsIncompleteArrayType(T)) { 3361 if (RequireCompleteType(IDecl->getLocation(), 3362 ArrayT->getElementType(), 3363 diag::err_illegal_decl_array_incomplete_type)) 3364 IDecl->setInvalidDecl(); 3365 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3366 // C99 6.9.2p3: If the declaration of an identifier for an object is 3367 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3368 // declared type shall not be an incomplete type. 3369 // NOTE: code such as the following 3370 // static struct s; 3371 // struct s { int a; }; 3372 // is accepted by gcc. Hence here we issue a warning instead of 3373 // an error and we do not invalidate the static declaration. 3374 // NOTE: to avoid multiple warnings, only check the first declaration. 3375 if (IDecl->getPreviousDeclaration() == 0) 3376 RequireCompleteType(IDecl->getLocation(), T, 3377 diag::ext_typecheck_decl_incomplete_type); 3378 } 3379 } 3380 } 3381 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3382 Decls.data(), Decls.size())); 3383} 3384 3385 3386/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3387/// to introduce parameters into function prototype scope. 3388Sema::DeclPtrTy 3389Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3390 const DeclSpec &DS = D.getDeclSpec(); 3391 3392 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3393 VarDecl::StorageClass StorageClass = VarDecl::None; 3394 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3395 StorageClass = VarDecl::Register; 3396 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3397 Diag(DS.getStorageClassSpecLoc(), 3398 diag::err_invalid_storage_class_in_func_decl); 3399 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3400 } 3401 3402 if (D.getDeclSpec().isThreadSpecified()) 3403 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3404 3405 DiagnoseFunctionSpecifiers(D); 3406 3407 // Check that there are no default arguments inside the type of this 3408 // parameter (C++ only). 3409 if (getLangOptions().CPlusPlus) 3410 CheckExtraCXXDefaultArguments(D); 3411 3412 DeclaratorInfo *DInfo = 0; 3413 TagDecl *OwnedDecl = 0; 3414 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3415 &OwnedDecl); 3416 3417 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3418 // C++ [dcl.fct]p6: 3419 // Types shall not be defined in return or parameter types. 3420 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3421 << Context.getTypeDeclType(OwnedDecl); 3422 } 3423 3424 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3425 // Can this happen for params? We already checked that they don't conflict 3426 // among each other. Here they can only shadow globals, which is ok. 3427 IdentifierInfo *II = D.getIdentifier(); 3428 if (II) { 3429 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3430 if (PrevDecl->isTemplateParameter()) { 3431 // Maybe we will complain about the shadowed template parameter. 3432 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3433 // Just pretend that we didn't see the previous declaration. 3434 PrevDecl = 0; 3435 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3436 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3437 3438 // Recover by removing the name 3439 II = 0; 3440 D.SetIdentifier(0, D.getIdentifierLoc()); 3441 } 3442 } 3443 } 3444 3445 // Parameters can not be abstract class types. 3446 // For record types, this is done by the AbstractClassUsageDiagnoser once 3447 // the class has been completely parsed. 3448 if (!CurContext->isRecord() && 3449 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3450 diag::err_abstract_type_in_decl, 3451 AbstractParamType)) 3452 D.setInvalidType(true); 3453 3454 QualType T = adjustParameterType(parmDeclType); 3455 3456 ParmVarDecl *New; 3457 if (T == parmDeclType) // parameter type did not need adjustment 3458 New = ParmVarDecl::Create(Context, CurContext, 3459 D.getIdentifierLoc(), II, 3460 parmDeclType, DInfo, StorageClass, 3461 0); 3462 else // keep track of both the adjusted and unadjusted types 3463 New = OriginalParmVarDecl::Create(Context, CurContext, 3464 D.getIdentifierLoc(), II, T, DInfo, 3465 parmDeclType, StorageClass, 0); 3466 3467 if (D.isInvalidType()) 3468 New->setInvalidDecl(); 3469 3470 // Parameter declarators cannot be interface types. All ObjC objects are 3471 // passed by reference. 3472 if (T->isObjCInterfaceType()) { 3473 Diag(D.getIdentifierLoc(), 3474 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3475 New->setInvalidDecl(); 3476 } 3477 3478 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3479 if (D.getCXXScopeSpec().isSet()) { 3480 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3481 << D.getCXXScopeSpec().getRange(); 3482 New->setInvalidDecl(); 3483 } 3484 3485 // Add the parameter declaration into this scope. 3486 S->AddDecl(DeclPtrTy::make(New)); 3487 if (II) 3488 IdResolver.AddDecl(New); 3489 3490 ProcessDeclAttributes(S, New, D); 3491 3492 if (New->hasAttr<BlocksAttr>()) { 3493 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3494 } 3495 return DeclPtrTy::make(New); 3496} 3497 3498void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3499 SourceLocation LocAfterDecls) { 3500 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3501 "Not a function declarator!"); 3502 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3503 3504 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3505 // for a K&R function. 3506 if (!FTI.hasPrototype) { 3507 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3508 --i; 3509 if (FTI.ArgInfo[i].Param == 0) { 3510 std::string Code = " int "; 3511 Code += FTI.ArgInfo[i].Ident->getName(); 3512 Code += ";\n"; 3513 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3514 << FTI.ArgInfo[i].Ident 3515 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3516 3517 // Implicitly declare the argument as type 'int' for lack of a better 3518 // type. 3519 DeclSpec DS; 3520 const char* PrevSpec; // unused 3521 unsigned DiagID; // unused 3522 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3523 PrevSpec, DiagID); 3524 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3525 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3526 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3527 } 3528 } 3529 } 3530} 3531 3532Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3533 Declarator &D) { 3534 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3535 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3536 "Not a function declarator!"); 3537 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3538 3539 if (FTI.hasPrototype) { 3540 // FIXME: Diagnose arguments without names in C. 3541 } 3542 3543 Scope *ParentScope = FnBodyScope->getParent(); 3544 3545 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3546 MultiTemplateParamsArg(*this), 3547 /*IsFunctionDefinition=*/true); 3548 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3549} 3550 3551Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3552 if (!D) 3553 return D; 3554 FunctionDecl *FD = 0; 3555 3556 if (FunctionTemplateDecl *FunTmpl 3557 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3558 FD = FunTmpl->getTemplatedDecl(); 3559 else 3560 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3561 3562 CurFunctionNeedsScopeChecking = false; 3563 3564 // See if this is a redefinition. 3565 const FunctionDecl *Definition; 3566 if (FD->getBody(Definition)) { 3567 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3568 Diag(Definition->getLocation(), diag::note_previous_definition); 3569 } 3570 3571 // Builtin functions cannot be defined. 3572 if (unsigned BuiltinID = FD->getBuiltinID()) { 3573 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3574 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3575 FD->setInvalidDecl(); 3576 } 3577 } 3578 3579 // The return type of a function definition must be complete 3580 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3581 QualType ResultType = FD->getResultType(); 3582 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3583 !FD->isInvalidDecl() && 3584 RequireCompleteType(FD->getLocation(), ResultType, 3585 diag::err_func_def_incomplete_result)) 3586 FD->setInvalidDecl(); 3587 3588 // GNU warning -Wmissing-prototypes: 3589 // Warn if a global function is defined without a previous 3590 // prototype declaration. This warning is issued even if the 3591 // definition itself provides a prototype. The aim is to detect 3592 // global functions that fail to be declared in header files. 3593 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3594 !FD->isMain()) { 3595 bool MissingPrototype = true; 3596 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3597 Prev; Prev = Prev->getPreviousDeclaration()) { 3598 // Ignore any declarations that occur in function or method 3599 // scope, because they aren't visible from the header. 3600 if (Prev->getDeclContext()->isFunctionOrMethod()) 3601 continue; 3602 3603 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3604 break; 3605 } 3606 3607 if (MissingPrototype) 3608 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3609 } 3610 3611 if (FnBodyScope) 3612 PushDeclContext(FnBodyScope, FD); 3613 3614 // Check the validity of our function parameters 3615 CheckParmsForFunctionDef(FD); 3616 3617 // Introduce our parameters into the function scope 3618 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3619 ParmVarDecl *Param = FD->getParamDecl(p); 3620 Param->setOwningFunction(FD); 3621 3622 // If this has an identifier, add it to the scope stack. 3623 if (Param->getIdentifier() && FnBodyScope) 3624 PushOnScopeChains(Param, FnBodyScope); 3625 } 3626 3627 // Checking attributes of current function definition 3628 // dllimport attribute. 3629 if (FD->getAttr<DLLImportAttr>() && 3630 (!FD->getAttr<DLLExportAttr>())) { 3631 // dllimport attribute cannot be applied to definition. 3632 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3633 Diag(FD->getLocation(), 3634 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3635 << "dllimport"; 3636 FD->setInvalidDecl(); 3637 return DeclPtrTy::make(FD); 3638 } else { 3639 // If a symbol previously declared dllimport is later defined, the 3640 // attribute is ignored in subsequent references, and a warning is 3641 // emitted. 3642 Diag(FD->getLocation(), 3643 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3644 << FD->getNameAsCString() << "dllimport"; 3645 } 3646 } 3647 return DeclPtrTy::make(FD); 3648} 3649 3650Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3651 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3652} 3653 3654Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3655 bool IsInstantiation) { 3656 Decl *dcl = D.getAs<Decl>(); 3657 Stmt *Body = BodyArg.takeAs<Stmt>(); 3658 3659 FunctionDecl *FD = 0; 3660 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3661 if (FunTmpl) 3662 FD = FunTmpl->getTemplatedDecl(); 3663 else 3664 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3665 3666 if (FD) { 3667 FD->setBody(Body); 3668 if (FD->isMain()) 3669 // C and C++ allow for main to automagically return 0. 3670 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3671 FD->setHasImplicitReturnZero(true); 3672 else 3673 CheckFallThroughForFunctionDef(FD, Body); 3674 3675 if (!FD->isInvalidDecl()) 3676 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3677 3678 // C++ [basic.def.odr]p2: 3679 // [...] A virtual member function is used if it is not pure. [...] 3680 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3681 if (Method->isVirtual() && !Method->isPure()) 3682 MarkDeclarationReferenced(Method->getLocation(), Method); 3683 3684 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3685 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3686 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3687 MD->setBody(Body); 3688 CheckFallThroughForFunctionDef(MD, Body); 3689 MD->setEndLoc(Body->getLocEnd()); 3690 3691 if (!MD->isInvalidDecl()) 3692 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3693 } else { 3694 Body->Destroy(Context); 3695 return DeclPtrTy(); 3696 } 3697 if (!IsInstantiation) 3698 PopDeclContext(); 3699 3700 // Verify and clean out per-function state. 3701 3702 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3703 3704 // Check goto/label use. 3705 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3706 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3707 LabelStmt *L = I->second; 3708 3709 // Verify that we have no forward references left. If so, there was a goto 3710 // or address of a label taken, but no definition of it. Label fwd 3711 // definitions are indicated with a null substmt. 3712 if (L->getSubStmt() != 0) 3713 continue; 3714 3715 // Emit error. 3716 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3717 3718 // At this point, we have gotos that use the bogus label. Stitch it into 3719 // the function body so that they aren't leaked and that the AST is well 3720 // formed. 3721 if (Body == 0) { 3722 // The whole function wasn't parsed correctly, just delete this. 3723 L->Destroy(Context); 3724 continue; 3725 } 3726 3727 // Otherwise, the body is valid: we want to stitch the label decl into the 3728 // function somewhere so that it is properly owned and so that the goto 3729 // has a valid target. Do this by creating a new compound stmt with the 3730 // label in it. 3731 3732 // Give the label a sub-statement. 3733 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3734 3735 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3736 cast<CXXTryStmt>(Body)->getTryBlock() : 3737 cast<CompoundStmt>(Body); 3738 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3739 Elements.push_back(L); 3740 Compound->setStmts(Context, &Elements[0], Elements.size()); 3741 } 3742 FunctionLabelMap.clear(); 3743 3744 if (!Body) return D; 3745 3746 // Verify that that gotos and switch cases don't jump into scopes illegally. 3747 if (CurFunctionNeedsScopeChecking) 3748 DiagnoseInvalidJumps(Body); 3749 3750 // C++ constructors that have function-try-blocks can't have return 3751 // statements in the handlers of that block. (C++ [except.handle]p14) 3752 // Verify this. 3753 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3754 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3755 3756 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3757 computeBaseOrMembersToDestroy(Destructor); 3758 return D; 3759} 3760 3761/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3762/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3763NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3764 IdentifierInfo &II, Scope *S) { 3765 // Before we produce a declaration for an implicitly defined 3766 // function, see whether there was a locally-scoped declaration of 3767 // this name as a function or variable. If so, use that 3768 // (non-visible) declaration, and complain about it. 3769 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3770 = LocallyScopedExternalDecls.find(&II); 3771 if (Pos != LocallyScopedExternalDecls.end()) { 3772 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3773 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3774 return Pos->second; 3775 } 3776 3777 // Extension in C99. Legal in C90, but warn about it. 3778 if (getLangOptions().C99) 3779 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3780 else 3781 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3782 3783 // FIXME: handle stuff like: 3784 // void foo() { extern float X(); } 3785 // void bar() { X(); } <-- implicit decl for X in another scope. 3786 3787 // Set a Declarator for the implicit definition: int foo(); 3788 const char *Dummy; 3789 DeclSpec DS; 3790 unsigned DiagID; 3791 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3792 Error = Error; // Silence warning. 3793 assert(!Error && "Error setting up implicit decl!"); 3794 Declarator D(DS, Declarator::BlockContext); 3795 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3796 0, 0, false, SourceLocation(), 3797 false, 0,0,0, Loc, Loc, D), 3798 SourceLocation()); 3799 D.SetIdentifier(&II, Loc); 3800 3801 // Insert this function into translation-unit scope. 3802 3803 DeclContext *PrevDC = CurContext; 3804 CurContext = Context.getTranslationUnitDecl(); 3805 3806 FunctionDecl *FD = 3807 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3808 FD->setImplicit(); 3809 3810 CurContext = PrevDC; 3811 3812 AddKnownFunctionAttributes(FD); 3813 3814 return FD; 3815} 3816 3817/// \brief Adds any function attributes that we know a priori based on 3818/// the declaration of this function. 3819/// 3820/// These attributes can apply both to implicitly-declared builtins 3821/// (like __builtin___printf_chk) or to library-declared functions 3822/// like NSLog or printf. 3823void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3824 if (FD->isInvalidDecl()) 3825 return; 3826 3827 // If this is a built-in function, map its builtin attributes to 3828 // actual attributes. 3829 if (unsigned BuiltinID = FD->getBuiltinID()) { 3830 // Handle printf-formatting attributes. 3831 unsigned FormatIdx; 3832 bool HasVAListArg; 3833 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3834 if (!FD->getAttr<FormatAttr>()) 3835 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3836 HasVAListArg ? 0 : FormatIdx + 2)); 3837 } 3838 3839 // Mark const if we don't care about errno and that is the only 3840 // thing preventing the function from being const. This allows 3841 // IRgen to use LLVM intrinsics for such functions. 3842 if (!getLangOptions().MathErrno && 3843 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3844 if (!FD->getAttr<ConstAttr>()) 3845 FD->addAttr(::new (Context) ConstAttr()); 3846 } 3847 3848 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3849 FD->addAttr(::new (Context) NoReturnAttr()); 3850 } 3851 3852 IdentifierInfo *Name = FD->getIdentifier(); 3853 if (!Name) 3854 return; 3855 if ((!getLangOptions().CPlusPlus && 3856 FD->getDeclContext()->isTranslationUnit()) || 3857 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3858 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3859 LinkageSpecDecl::lang_c)) { 3860 // Okay: this could be a libc/libm/Objective-C function we know 3861 // about. 3862 } else 3863 return; 3864 3865 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3866 // FIXME: NSLog and NSLogv should be target specific 3867 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3868 // FIXME: We known better than our headers. 3869 const_cast<FormatAttr *>(Format)->setType("printf"); 3870 } else 3871 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3872 Name->isStr("NSLogv") ? 0 : 2)); 3873 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3874 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3875 // target-specific builtins, perhaps? 3876 if (!FD->getAttr<FormatAttr>()) 3877 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3878 Name->isStr("vasprintf") ? 0 : 3)); 3879 } 3880} 3881 3882TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3883 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3884 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3885 3886 // Scope manipulation handled by caller. 3887 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3888 D.getIdentifierLoc(), 3889 D.getIdentifier(), 3890 T); 3891 3892 if (const TagType *TT = T->getAs<TagType>()) { 3893 TagDecl *TD = TT->getDecl(); 3894 3895 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3896 // keep track of the TypedefDecl. 3897 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3898 TD->setTypedefForAnonDecl(NewTD); 3899 } 3900 3901 if (D.isInvalidType()) 3902 NewTD->setInvalidDecl(); 3903 return NewTD; 3904} 3905 3906 3907/// \brief Determine whether a tag with a given kind is acceptable 3908/// as a redeclaration of the given tag declaration. 3909/// 3910/// \returns true if the new tag kind is acceptable, false otherwise. 3911bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3912 TagDecl::TagKind NewTag, 3913 SourceLocation NewTagLoc, 3914 const IdentifierInfo &Name) { 3915 // C++ [dcl.type.elab]p3: 3916 // The class-key or enum keyword present in the 3917 // elaborated-type-specifier shall agree in kind with the 3918 // declaration to which the name in theelaborated-type-specifier 3919 // refers. This rule also applies to the form of 3920 // elaborated-type-specifier that declares a class-name or 3921 // friend class since it can be construed as referring to the 3922 // definition of the class. Thus, in any 3923 // elaborated-type-specifier, the enum keyword shall be used to 3924 // refer to an enumeration (7.2), the union class-keyshall be 3925 // used to refer to a union (clause 9), and either the class or 3926 // struct class-key shall be used to refer to a class (clause 9) 3927 // declared using the class or struct class-key. 3928 TagDecl::TagKind OldTag = Previous->getTagKind(); 3929 if (OldTag == NewTag) 3930 return true; 3931 3932 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3933 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3934 // Warn about the struct/class tag mismatch. 3935 bool isTemplate = false; 3936 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3937 isTemplate = Record->getDescribedClassTemplate(); 3938 3939 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3940 << (NewTag == TagDecl::TK_class) 3941 << isTemplate << &Name 3942 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3943 OldTag == TagDecl::TK_class? "class" : "struct"); 3944 Diag(Previous->getLocation(), diag::note_previous_use); 3945 return true; 3946 } 3947 return false; 3948} 3949 3950/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3951/// former case, Name will be non-null. In the later case, Name will be null. 3952/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3953/// reference/declaration/definition of a tag. 3954Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3955 SourceLocation KWLoc, const CXXScopeSpec &SS, 3956 IdentifierInfo *Name, SourceLocation NameLoc, 3957 AttributeList *Attr, AccessSpecifier AS, 3958 MultiTemplateParamsArg TemplateParameterLists, 3959 bool &OwnedDecl, bool &IsDependent) { 3960 // If this is not a definition, it must have a name. 3961 assert((Name != 0 || TUK == TUK_Definition) && 3962 "Nameless record must be a definition!"); 3963 3964 OwnedDecl = false; 3965 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 3966 3967 if (TUK != TUK_Reference) { 3968 if (TemplateParameterList *TemplateParams 3969 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3970 (TemplateParameterList**)TemplateParameterLists.get(), 3971 TemplateParameterLists.size())) { 3972 if (TemplateParams->size() > 0) { 3973 // This is a declaration or definition of a class template (which may 3974 // be a member of another template). 3975 OwnedDecl = false; 3976 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 3977 SS, Name, NameLoc, Attr, 3978 TemplateParams, 3979 AS); 3980 TemplateParameterLists.release(); 3981 return Result.get(); 3982 } else { 3983 // FIXME: diagnose the extraneous 'template<>', once we recover 3984 // slightly better in ParseTemplate.cpp from bogus template 3985 // parameters. 3986 } 3987 } 3988 } 3989 3990 DeclContext *SearchDC = CurContext; 3991 DeclContext *DC = CurContext; 3992 NamedDecl *PrevDecl = 0; 3993 3994 bool Invalid = false; 3995 3996 if (Name && SS.isNotEmpty()) { 3997 // We have a nested-name tag ('struct foo::bar'). 3998 3999 // Check for invalid 'foo::'. 4000 if (SS.isInvalid()) { 4001 Name = 0; 4002 goto CreateNewDecl; 4003 } 4004 4005 // If this is a friend or a reference to a class in a dependent 4006 // context, don't try to make a decl for it. 4007 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4008 DC = computeDeclContext(SS, false); 4009 if (!DC) { 4010 IsDependent = true; 4011 return DeclPtrTy(); 4012 } 4013 } 4014 4015 if (RequireCompleteDeclContext(SS)) 4016 return DeclPtrTy::make((Decl *)0); 4017 4018 DC = computeDeclContext(SS, true); 4019 SearchDC = DC; 4020 // Look-up name inside 'foo::'. 4021 PrevDecl 4022 = dyn_cast_or_null<TagDecl>( 4023 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4024 4025 // A tag 'foo::bar' must already exist. 4026 if (PrevDecl == 0) { 4027 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4028 Name = 0; 4029 Invalid = true; 4030 goto CreateNewDecl; 4031 } 4032 } else if (Name) { 4033 // If this is a named struct, check to see if there was a previous forward 4034 // declaration or definition. 4035 // FIXME: We're looking into outer scopes here, even when we 4036 // shouldn't be. Doing so can result in ambiguities that we 4037 // shouldn't be diagnosing. 4038 LookupResult R = LookupName(S, Name, LookupTagName, 4039 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4040 if (R.isAmbiguous()) { 4041 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4042 // FIXME: This is not best way to recover from case like: 4043 // 4044 // struct S s; 4045 // 4046 // causes needless "incomplete type" error later. 4047 Name = 0; 4048 PrevDecl = 0; 4049 Invalid = true; 4050 } else 4051 PrevDecl = R; 4052 4053 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4054 // FIXME: This makes sure that we ignore the contexts associated 4055 // with C structs, unions, and enums when looking for a matching 4056 // tag declaration or definition. See the similar lookup tweak 4057 // in Sema::LookupName; is there a better way to deal with this? 4058 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4059 SearchDC = SearchDC->getParent(); 4060 } 4061 } 4062 4063 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4064 // Maybe we will complain about the shadowed template parameter. 4065 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4066 // Just pretend that we didn't see the previous declaration. 4067 PrevDecl = 0; 4068 } 4069 4070 if (PrevDecl) { 4071 // Check whether the previous declaration is usable. 4072 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4073 4074 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4075 // If this is a use of a previous tag, or if the tag is already declared 4076 // in the same scope (so that the definition/declaration completes or 4077 // rementions the tag), reuse the decl. 4078 if (TUK == TUK_Reference || TUK == TUK_Friend || 4079 isDeclInScope(PrevDecl, SearchDC, S)) { 4080 // Make sure that this wasn't declared as an enum and now used as a 4081 // struct or something similar. 4082 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4083 bool SafeToContinue 4084 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4085 Kind != TagDecl::TK_enum); 4086 if (SafeToContinue) 4087 Diag(KWLoc, diag::err_use_with_wrong_tag) 4088 << Name 4089 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4090 PrevTagDecl->getKindName()); 4091 else 4092 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4093 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4094 4095 if (SafeToContinue) 4096 Kind = PrevTagDecl->getTagKind(); 4097 else { 4098 // Recover by making this an anonymous redefinition. 4099 Name = 0; 4100 PrevDecl = 0; 4101 Invalid = true; 4102 } 4103 } 4104 4105 if (!Invalid) { 4106 // If this is a use, just return the declaration we found. 4107 4108 // FIXME: In the future, return a variant or some other clue 4109 // for the consumer of this Decl to know it doesn't own it. 4110 // For our current ASTs this shouldn't be a problem, but will 4111 // need to be changed with DeclGroups. 4112 if (TUK == TUK_Reference) 4113 return DeclPtrTy::make(PrevDecl); 4114 4115 // If this is a friend, make sure we create the new 4116 // declaration in the appropriate semantic context. 4117 if (TUK == TUK_Friend) 4118 SearchDC = PrevDecl->getDeclContext(); 4119 4120 // Diagnose attempts to redefine a tag. 4121 if (TUK == TUK_Definition) { 4122 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4123 Diag(NameLoc, diag::err_redefinition) << Name; 4124 Diag(Def->getLocation(), diag::note_previous_definition); 4125 // If this is a redefinition, recover by making this 4126 // struct be anonymous, which will make any later 4127 // references get the previous definition. 4128 Name = 0; 4129 PrevDecl = 0; 4130 Invalid = true; 4131 } else { 4132 // If the type is currently being defined, complain 4133 // about a nested redefinition. 4134 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4135 if (Tag->isBeingDefined()) { 4136 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4137 Diag(PrevTagDecl->getLocation(), 4138 diag::note_previous_definition); 4139 Name = 0; 4140 PrevDecl = 0; 4141 Invalid = true; 4142 } 4143 } 4144 4145 // Okay, this is definition of a previously declared or referenced 4146 // tag PrevDecl. We're going to create a new Decl for it. 4147 } 4148 } 4149 // If we get here we have (another) forward declaration or we 4150 // have a definition. Just create a new decl. 4151 4152 } else { 4153 // If we get here, this is a definition of a new tag type in a nested 4154 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4155 // new decl/type. We set PrevDecl to NULL so that the entities 4156 // have distinct types. 4157 PrevDecl = 0; 4158 } 4159 // If we get here, we're going to create a new Decl. If PrevDecl 4160 // is non-NULL, it's a definition of the tag declared by 4161 // PrevDecl. If it's NULL, we have a new definition. 4162 } else { 4163 // PrevDecl is a namespace, template, or anything else 4164 // that lives in the IDNS_Tag identifier namespace. 4165 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4166 // The tag name clashes with a namespace name, issue an error and 4167 // recover by making this tag be anonymous. 4168 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4169 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4170 Name = 0; 4171 PrevDecl = 0; 4172 Invalid = true; 4173 } else { 4174 // The existing declaration isn't relevant to us; we're in a 4175 // new scope, so clear out the previous declaration. 4176 PrevDecl = 0; 4177 } 4178 } 4179 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4180 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4181 // C++ [basic.scope.pdecl]p5: 4182 // -- for an elaborated-type-specifier of the form 4183 // 4184 // class-key identifier 4185 // 4186 // if the elaborated-type-specifier is used in the 4187 // decl-specifier-seq or parameter-declaration-clause of a 4188 // function defined in namespace scope, the identifier is 4189 // declared as a class-name in the namespace that contains 4190 // the declaration; otherwise, except as a friend 4191 // declaration, the identifier is declared in the smallest 4192 // non-class, non-function-prototype scope that contains the 4193 // declaration. 4194 // 4195 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4196 // C structs and unions. 4197 // 4198 // GNU C also supports this behavior as part of its incomplete 4199 // enum types extension, while GNU C++ does not. 4200 // 4201 // Find the context where we'll be declaring the tag. 4202 // FIXME: We would like to maintain the current DeclContext as the 4203 // lexical context, 4204 while (SearchDC->isRecord()) 4205 SearchDC = SearchDC->getParent(); 4206 4207 // Find the scope where we'll be declaring the tag. 4208 while (S->isClassScope() || 4209 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4210 ((S->getFlags() & Scope::DeclScope) == 0) || 4211 (S->getEntity() && 4212 ((DeclContext *)S->getEntity())->isTransparentContext())) 4213 S = S->getParent(); 4214 4215 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4216 // C++ [namespace.memdef]p3: 4217 // If a friend declaration in a non-local class first declares a 4218 // class or function, the friend class or function is a member of 4219 // the innermost enclosing namespace. 4220 while (!SearchDC->isFileContext()) 4221 SearchDC = SearchDC->getParent(); 4222 4223 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4224 while (S->getEntity() != SearchDC) 4225 S = S->getParent(); 4226 } 4227 4228CreateNewDecl: 4229 4230 // If there is an identifier, use the location of the identifier as the 4231 // location of the decl, otherwise use the location of the struct/union 4232 // keyword. 4233 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4234 4235 // Otherwise, create a new declaration. If there is a previous 4236 // declaration of the same entity, the two will be linked via 4237 // PrevDecl. 4238 TagDecl *New; 4239 4240 if (Kind == TagDecl::TK_enum) { 4241 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4242 // enum X { A, B, C } D; D should chain to X. 4243 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4244 cast_or_null<EnumDecl>(PrevDecl)); 4245 // If this is an undefined enum, warn. 4246 if (TUK != TUK_Definition && !Invalid) { 4247 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4248 : diag::ext_forward_ref_enum; 4249 Diag(Loc, DK); 4250 } 4251 } else { 4252 // struct/union/class 4253 4254 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4255 // struct X { int A; } D; D should chain to X. 4256 if (getLangOptions().CPlusPlus) 4257 // FIXME: Look for a way to use RecordDecl for simple structs. 4258 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4259 cast_or_null<CXXRecordDecl>(PrevDecl)); 4260 else 4261 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4262 cast_or_null<RecordDecl>(PrevDecl)); 4263 } 4264 4265 if (Kind != TagDecl::TK_enum) { 4266 // Handle #pragma pack: if the #pragma pack stack has non-default 4267 // alignment, make up a packed attribute for this decl. These 4268 // attributes are checked when the ASTContext lays out the 4269 // structure. 4270 // 4271 // It is important for implementing the correct semantics that this 4272 // happen here (in act on tag decl). The #pragma pack stack is 4273 // maintained as a result of parser callbacks which can occur at 4274 // many points during the parsing of a struct declaration (because 4275 // the #pragma tokens are effectively skipped over during the 4276 // parsing of the struct). 4277 if (unsigned Alignment = getPragmaPackAlignment()) 4278 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4279 } 4280 4281 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4282 // C++ [dcl.typedef]p3: 4283 // [...] Similarly, in a given scope, a class or enumeration 4284 // shall not be declared with the same name as a typedef-name 4285 // that is declared in that scope and refers to a type other 4286 // than the class or enumeration itself. 4287 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4288 TypedefDecl *PrevTypedef = 0; 4289 if (Lookup.getKind() == LookupResult::Found) 4290 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4291 4292 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4293 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4294 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4295 Diag(Loc, diag::err_tag_definition_of_typedef) 4296 << Context.getTypeDeclType(New) 4297 << PrevTypedef->getUnderlyingType(); 4298 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4299 Invalid = true; 4300 } 4301 } 4302 4303 if (Invalid) 4304 New->setInvalidDecl(); 4305 4306 if (Attr) 4307 ProcessDeclAttributeList(S, New, Attr); 4308 4309 // If we're declaring or defining a tag in function prototype scope 4310 // in C, note that this type can only be used within the function. 4311 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4312 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4313 4314 // Set the lexical context. If the tag has a C++ scope specifier, the 4315 // lexical context will be different from the semantic context. 4316 New->setLexicalDeclContext(CurContext); 4317 4318 // Mark this as a friend decl if applicable. 4319 if (TUK == TUK_Friend) 4320 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4321 4322 // Set the access specifier. 4323 if (!Invalid && TUK != TUK_Friend) 4324 SetMemberAccessSpecifier(New, PrevDecl, AS); 4325 4326 if (TUK == TUK_Definition) 4327 New->startDefinition(); 4328 4329 // If this has an identifier, add it to the scope stack. 4330 if (TUK == TUK_Friend) { 4331 // We might be replacing an existing declaration in the lookup tables; 4332 // if so, borrow its access specifier. 4333 if (PrevDecl) 4334 New->setAccess(PrevDecl->getAccess()); 4335 4336 // Friend tag decls are visible in fairly strange ways. 4337 if (!CurContext->isDependentContext()) { 4338 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4339 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4340 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4341 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4342 } 4343 } else if (Name) { 4344 S = getNonFieldDeclScope(S); 4345 PushOnScopeChains(New, S); 4346 } else { 4347 CurContext->addDecl(New); 4348 } 4349 4350 // If this is the C FILE type, notify the AST context. 4351 if (IdentifierInfo *II = New->getIdentifier()) 4352 if (!New->isInvalidDecl() && 4353 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4354 II->isStr("FILE")) 4355 Context.setFILEDecl(New); 4356 4357 OwnedDecl = true; 4358 return DeclPtrTy::make(New); 4359} 4360 4361void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4362 AdjustDeclIfTemplate(TagD); 4363 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4364 4365 // Enter the tag context. 4366 PushDeclContext(S, Tag); 4367 4368 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4369 FieldCollector->StartClass(); 4370 4371 if (Record->getIdentifier()) { 4372 // C++ [class]p2: 4373 // [...] The class-name is also inserted into the scope of the 4374 // class itself; this is known as the injected-class-name. For 4375 // purposes of access checking, the injected-class-name is treated 4376 // as if it were a public member name. 4377 CXXRecordDecl *InjectedClassName 4378 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4379 CurContext, Record->getLocation(), 4380 Record->getIdentifier(), 4381 Record->getTagKeywordLoc(), 4382 Record); 4383 InjectedClassName->setImplicit(); 4384 InjectedClassName->setAccess(AS_public); 4385 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4386 InjectedClassName->setDescribedClassTemplate(Template); 4387 PushOnScopeChains(InjectedClassName, S); 4388 assert(InjectedClassName->isInjectedClassName() && 4389 "Broken injected-class-name"); 4390 } 4391 } 4392} 4393 4394void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4395 SourceLocation RBraceLoc) { 4396 AdjustDeclIfTemplate(TagD); 4397 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4398 Tag->setRBraceLoc(RBraceLoc); 4399 4400 if (isa<CXXRecordDecl>(Tag)) 4401 FieldCollector->FinishClass(); 4402 4403 // Exit this scope of this tag's definition. 4404 PopDeclContext(); 4405 4406 // Notify the consumer that we've defined a tag. 4407 Consumer.HandleTagDeclDefinition(Tag); 4408} 4409 4410// Note that FieldName may be null for anonymous bitfields. 4411bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4412 QualType FieldTy, const Expr *BitWidth, 4413 bool *ZeroWidth) { 4414 // Default to true; that shouldn't confuse checks for emptiness 4415 if (ZeroWidth) 4416 *ZeroWidth = true; 4417 4418 // C99 6.7.2.1p4 - verify the field type. 4419 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4420 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4421 // Handle incomplete types with specific error. 4422 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4423 return true; 4424 if (FieldName) 4425 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4426 << FieldName << FieldTy << BitWidth->getSourceRange(); 4427 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4428 << FieldTy << BitWidth->getSourceRange(); 4429 } 4430 4431 // If the bit-width is type- or value-dependent, don't try to check 4432 // it now. 4433 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4434 return false; 4435 4436 llvm::APSInt Value; 4437 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4438 return true; 4439 4440 if (Value != 0 && ZeroWidth) 4441 *ZeroWidth = false; 4442 4443 // Zero-width bitfield is ok for anonymous field. 4444 if (Value == 0 && FieldName) 4445 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4446 4447 if (Value.isSigned() && Value.isNegative()) { 4448 if (FieldName) 4449 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4450 << FieldName << Value.toString(10); 4451 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4452 << Value.toString(10); 4453 } 4454 4455 if (!FieldTy->isDependentType()) { 4456 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4457 if (Value.getZExtValue() > TypeSize) { 4458 if (FieldName) 4459 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4460 << FieldName << (unsigned)TypeSize; 4461 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4462 << (unsigned)TypeSize; 4463 } 4464 } 4465 4466 return false; 4467} 4468 4469/// ActOnField - Each field of a struct/union/class is passed into this in order 4470/// to create a FieldDecl object for it. 4471Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4472 SourceLocation DeclStart, 4473 Declarator &D, ExprTy *BitfieldWidth) { 4474 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4475 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4476 AS_public); 4477 return DeclPtrTy::make(Res); 4478} 4479 4480/// HandleField - Analyze a field of a C struct or a C++ data member. 4481/// 4482FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4483 SourceLocation DeclStart, 4484 Declarator &D, Expr *BitWidth, 4485 AccessSpecifier AS) { 4486 IdentifierInfo *II = D.getIdentifier(); 4487 SourceLocation Loc = DeclStart; 4488 if (II) Loc = D.getIdentifierLoc(); 4489 4490 DeclaratorInfo *DInfo = 0; 4491 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4492 if (getLangOptions().CPlusPlus) 4493 CheckExtraCXXDefaultArguments(D); 4494 4495 DiagnoseFunctionSpecifiers(D); 4496 4497 if (D.getDeclSpec().isThreadSpecified()) 4498 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4499 4500 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4501 4502 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4503 // Maybe we will complain about the shadowed template parameter. 4504 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4505 // Just pretend that we didn't see the previous declaration. 4506 PrevDecl = 0; 4507 } 4508 4509 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4510 PrevDecl = 0; 4511 4512 bool Mutable 4513 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4514 SourceLocation TSSL = D.getSourceRange().getBegin(); 4515 FieldDecl *NewFD 4516 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4517 AS, PrevDecl, &D); 4518 if (NewFD->isInvalidDecl() && PrevDecl) { 4519 // Don't introduce NewFD into scope; there's already something 4520 // with the same name in the same scope. 4521 } else if (II) { 4522 PushOnScopeChains(NewFD, S); 4523 } else 4524 Record->addDecl(NewFD); 4525 4526 return NewFD; 4527} 4528 4529/// \brief Build a new FieldDecl and check its well-formedness. 4530/// 4531/// This routine builds a new FieldDecl given the fields name, type, 4532/// record, etc. \p PrevDecl should refer to any previous declaration 4533/// with the same name and in the same scope as the field to be 4534/// created. 4535/// 4536/// \returns a new FieldDecl. 4537/// 4538/// \todo The Declarator argument is a hack. It will be removed once 4539FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4540 DeclaratorInfo *DInfo, 4541 RecordDecl *Record, SourceLocation Loc, 4542 bool Mutable, Expr *BitWidth, 4543 SourceLocation TSSL, 4544 AccessSpecifier AS, NamedDecl *PrevDecl, 4545 Declarator *D) { 4546 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4547 bool InvalidDecl = false; 4548 if (D) InvalidDecl = D->isInvalidType(); 4549 4550 // If we receive a broken type, recover by assuming 'int' and 4551 // marking this declaration as invalid. 4552 if (T.isNull()) { 4553 InvalidDecl = true; 4554 T = Context.IntTy; 4555 } 4556 4557 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4558 // than a variably modified type. 4559 if (T->isVariablyModifiedType()) { 4560 bool SizeIsNegative; 4561 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4562 SizeIsNegative); 4563 if (!FixedTy.isNull()) { 4564 Diag(Loc, diag::warn_illegal_constant_array_size); 4565 T = FixedTy; 4566 } else { 4567 if (SizeIsNegative) 4568 Diag(Loc, diag::err_typecheck_negative_array_size); 4569 else 4570 Diag(Loc, diag::err_typecheck_field_variable_size); 4571 InvalidDecl = true; 4572 } 4573 } 4574 4575 // Fields can not have abstract class types 4576 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4577 AbstractFieldType)) 4578 InvalidDecl = true; 4579 4580 bool ZeroWidth = false; 4581 // If this is declared as a bit-field, check the bit-field. 4582 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4583 InvalidDecl = true; 4584 DeleteExpr(BitWidth); 4585 BitWidth = 0; 4586 ZeroWidth = false; 4587 } 4588 4589 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4590 BitWidth, Mutable); 4591 if (InvalidDecl) 4592 NewFD->setInvalidDecl(); 4593 4594 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4595 Diag(Loc, diag::err_duplicate_member) << II; 4596 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4597 NewFD->setInvalidDecl(); 4598 } 4599 4600 if (getLangOptions().CPlusPlus) { 4601 QualType EltTy = Context.getBaseElementType(T); 4602 4603 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4604 4605 if (!T->isPODType()) 4606 CXXRecord->setPOD(false); 4607 if (!ZeroWidth) 4608 CXXRecord->setEmpty(false); 4609 4610 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4611 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4612 4613 if (!RDecl->hasTrivialConstructor()) 4614 CXXRecord->setHasTrivialConstructor(false); 4615 if (!RDecl->hasTrivialCopyConstructor()) 4616 CXXRecord->setHasTrivialCopyConstructor(false); 4617 if (!RDecl->hasTrivialCopyAssignment()) 4618 CXXRecord->setHasTrivialCopyAssignment(false); 4619 if (!RDecl->hasTrivialDestructor()) 4620 CXXRecord->setHasTrivialDestructor(false); 4621 4622 // C++ 9.5p1: An object of a class with a non-trivial 4623 // constructor, a non-trivial copy constructor, a non-trivial 4624 // destructor, or a non-trivial copy assignment operator 4625 // cannot be a member of a union, nor can an array of such 4626 // objects. 4627 // TODO: C++0x alters this restriction significantly. 4628 if (Record->isUnion()) { 4629 // We check for copy constructors before constructors 4630 // because otherwise we'll never get complaints about 4631 // copy constructors. 4632 4633 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4634 4635 CXXSpecialMember member; 4636 if (!RDecl->hasTrivialCopyConstructor()) 4637 member = CXXCopyConstructor; 4638 else if (!RDecl->hasTrivialConstructor()) 4639 member = CXXDefaultConstructor; 4640 else if (!RDecl->hasTrivialCopyAssignment()) 4641 member = CXXCopyAssignment; 4642 else if (!RDecl->hasTrivialDestructor()) 4643 member = CXXDestructor; 4644 else 4645 member = invalid; 4646 4647 if (member != invalid) { 4648 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4649 DiagnoseNontrivial(RT, member); 4650 NewFD->setInvalidDecl(); 4651 } 4652 } 4653 } 4654 } 4655 4656 // FIXME: We need to pass in the attributes given an AST 4657 // representation, not a parser representation. 4658 if (D) 4659 // FIXME: What to pass instead of TUScope? 4660 ProcessDeclAttributes(TUScope, NewFD, *D); 4661 4662 if (T.isObjCGCWeak()) 4663 Diag(Loc, diag::warn_attribute_weak_on_field); 4664 4665 NewFD->setAccess(AS); 4666 4667 // C++ [dcl.init.aggr]p1: 4668 // An aggregate is an array or a class (clause 9) with [...] no 4669 // private or protected non-static data members (clause 11). 4670 // A POD must be an aggregate. 4671 if (getLangOptions().CPlusPlus && 4672 (AS == AS_private || AS == AS_protected)) { 4673 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4674 CXXRecord->setAggregate(false); 4675 CXXRecord->setPOD(false); 4676 } 4677 4678 return NewFD; 4679} 4680 4681/// DiagnoseNontrivial - Given that a class has a non-trivial 4682/// special member, figure out why. 4683void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4684 QualType QT(T, 0U); 4685 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4686 4687 // Check whether the member was user-declared. 4688 switch (member) { 4689 case CXXDefaultConstructor: 4690 if (RD->hasUserDeclaredConstructor()) { 4691 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4692 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4693 if (!ci->isImplicitlyDefined(Context)) { 4694 SourceLocation CtorLoc = ci->getLocation(); 4695 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4696 return; 4697 } 4698 4699 assert(0 && "found no user-declared constructors"); 4700 return; 4701 } 4702 break; 4703 4704 case CXXCopyConstructor: 4705 if (RD->hasUserDeclaredCopyConstructor()) { 4706 SourceLocation CtorLoc = 4707 RD->getCopyConstructor(Context, 0)->getLocation(); 4708 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4709 return; 4710 } 4711 break; 4712 4713 case CXXCopyAssignment: 4714 if (RD->hasUserDeclaredCopyAssignment()) { 4715 // FIXME: this should use the location of the copy 4716 // assignment, not the type. 4717 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4718 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4719 return; 4720 } 4721 break; 4722 4723 case CXXDestructor: 4724 if (RD->hasUserDeclaredDestructor()) { 4725 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4726 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4727 return; 4728 } 4729 break; 4730 } 4731 4732 typedef CXXRecordDecl::base_class_iterator base_iter; 4733 4734 // Virtual bases and members inhibit trivial copying/construction, 4735 // but not trivial destruction. 4736 if (member != CXXDestructor) { 4737 // Check for virtual bases. vbases includes indirect virtual bases, 4738 // so we just iterate through the direct bases. 4739 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4740 if (bi->isVirtual()) { 4741 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4742 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4743 return; 4744 } 4745 4746 // Check for virtual methods. 4747 typedef CXXRecordDecl::method_iterator meth_iter; 4748 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4749 ++mi) { 4750 if (mi->isVirtual()) { 4751 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4752 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4753 return; 4754 } 4755 } 4756 } 4757 4758 bool (CXXRecordDecl::*hasTrivial)() const; 4759 switch (member) { 4760 case CXXDefaultConstructor: 4761 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4762 case CXXCopyConstructor: 4763 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4764 case CXXCopyAssignment: 4765 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4766 case CXXDestructor: 4767 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4768 default: 4769 assert(0 && "unexpected special member"); return; 4770 } 4771 4772 // Check for nontrivial bases (and recurse). 4773 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4774 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4775 assert(BaseRT); 4776 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4777 if (!(BaseRecTy->*hasTrivial)()) { 4778 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4779 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4780 DiagnoseNontrivial(BaseRT, member); 4781 return; 4782 } 4783 } 4784 4785 // Check for nontrivial members (and recurse). 4786 typedef RecordDecl::field_iterator field_iter; 4787 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4788 ++fi) { 4789 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4790 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4791 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4792 4793 if (!(EltRD->*hasTrivial)()) { 4794 SourceLocation FLoc = (*fi)->getLocation(); 4795 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4796 DiagnoseNontrivial(EltRT, member); 4797 return; 4798 } 4799 } 4800 } 4801 4802 assert(0 && "found no explanation for non-trivial member"); 4803} 4804 4805/// TranslateIvarVisibility - Translate visibility from a token ID to an 4806/// AST enum value. 4807static ObjCIvarDecl::AccessControl 4808TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4809 switch (ivarVisibility) { 4810 default: assert(0 && "Unknown visitibility kind"); 4811 case tok::objc_private: return ObjCIvarDecl::Private; 4812 case tok::objc_public: return ObjCIvarDecl::Public; 4813 case tok::objc_protected: return ObjCIvarDecl::Protected; 4814 case tok::objc_package: return ObjCIvarDecl::Package; 4815 } 4816} 4817 4818/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4819/// in order to create an IvarDecl object for it. 4820Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4821 SourceLocation DeclStart, 4822 DeclPtrTy IntfDecl, 4823 Declarator &D, ExprTy *BitfieldWidth, 4824 tok::ObjCKeywordKind Visibility) { 4825 4826 IdentifierInfo *II = D.getIdentifier(); 4827 Expr *BitWidth = (Expr*)BitfieldWidth; 4828 SourceLocation Loc = DeclStart; 4829 if (II) Loc = D.getIdentifierLoc(); 4830 4831 // FIXME: Unnamed fields can be handled in various different ways, for 4832 // example, unnamed unions inject all members into the struct namespace! 4833 4834 DeclaratorInfo *DInfo = 0; 4835 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4836 4837 if (BitWidth) { 4838 // 6.7.2.1p3, 6.7.2.1p4 4839 if (VerifyBitField(Loc, II, T, BitWidth)) { 4840 D.setInvalidType(); 4841 DeleteExpr(BitWidth); 4842 BitWidth = 0; 4843 } 4844 } else { 4845 // Not a bitfield. 4846 4847 // validate II. 4848 4849 } 4850 4851 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4852 // than a variably modified type. 4853 if (T->isVariablyModifiedType()) { 4854 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4855 D.setInvalidType(); 4856 } 4857 4858 // Get the visibility (access control) for this ivar. 4859 ObjCIvarDecl::AccessControl ac = 4860 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4861 : ObjCIvarDecl::None; 4862 // Must set ivar's DeclContext to its enclosing interface. 4863 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4864 DeclContext *EnclosingContext; 4865 if (ObjCImplementationDecl *IMPDecl = 4866 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4867 // Case of ivar declared in an implementation. Context is that of its class. 4868 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4869 assert(IDecl && "No class- ActOnIvar"); 4870 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4871 } else 4872 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4873 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4874 4875 // Construct the decl. 4876 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4877 EnclosingContext, Loc, II, T, 4878 DInfo, ac, (Expr *)BitfieldWidth); 4879 4880 if (II) { 4881 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4882 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4883 && !isa<TagDecl>(PrevDecl)) { 4884 Diag(Loc, diag::err_duplicate_member) << II; 4885 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4886 NewID->setInvalidDecl(); 4887 } 4888 } 4889 4890 // Process attributes attached to the ivar. 4891 ProcessDeclAttributes(S, NewID, D); 4892 4893 if (D.isInvalidType()) 4894 NewID->setInvalidDecl(); 4895 4896 if (II) { 4897 // FIXME: When interfaces are DeclContexts, we'll need to add 4898 // these to the interface. 4899 S->AddDecl(DeclPtrTy::make(NewID)); 4900 IdResolver.AddDecl(NewID); 4901 } 4902 4903 return DeclPtrTy::make(NewID); 4904} 4905 4906void Sema::ActOnFields(Scope* S, 4907 SourceLocation RecLoc, DeclPtrTy RecDecl, 4908 DeclPtrTy *Fields, unsigned NumFields, 4909 SourceLocation LBrac, SourceLocation RBrac, 4910 AttributeList *Attr) { 4911 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4912 assert(EnclosingDecl && "missing record or interface decl"); 4913 4914 // If the decl this is being inserted into is invalid, then it may be a 4915 // redeclaration or some other bogus case. Don't try to add fields to it. 4916 if (EnclosingDecl->isInvalidDecl()) { 4917 // FIXME: Deallocate fields? 4918 return; 4919 } 4920 4921 4922 // Verify that all the fields are okay. 4923 unsigned NumNamedMembers = 0; 4924 llvm::SmallVector<FieldDecl*, 32> RecFields; 4925 4926 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4927 for (unsigned i = 0; i != NumFields; ++i) { 4928 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4929 4930 // Get the type for the field. 4931 Type *FDTy = FD->getType().getTypePtr(); 4932 4933 if (!FD->isAnonymousStructOrUnion()) { 4934 // Remember all fields written by the user. 4935 RecFields.push_back(FD); 4936 } 4937 4938 // If the field is already invalid for some reason, don't emit more 4939 // diagnostics about it. 4940 if (FD->isInvalidDecl()) 4941 continue; 4942 4943 // C99 6.7.2.1p2: 4944 // A structure or union shall not contain a member with 4945 // incomplete or function type (hence, a structure shall not 4946 // contain an instance of itself, but may contain a pointer to 4947 // an instance of itself), except that the last member of a 4948 // structure with more than one named member may have incomplete 4949 // array type; such a structure (and any union containing, 4950 // possibly recursively, a member that is such a structure) 4951 // shall not be a member of a structure or an element of an 4952 // array. 4953 if (FDTy->isFunctionType()) { 4954 // Field declared as a function. 4955 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4956 << FD->getDeclName(); 4957 FD->setInvalidDecl(); 4958 EnclosingDecl->setInvalidDecl(); 4959 continue; 4960 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4961 Record && Record->isStruct()) { 4962 // Flexible array member. 4963 if (NumNamedMembers < 1) { 4964 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4965 << FD->getDeclName(); 4966 FD->setInvalidDecl(); 4967 EnclosingDecl->setInvalidDecl(); 4968 continue; 4969 } 4970 // Okay, we have a legal flexible array member at the end of the struct. 4971 if (Record) 4972 Record->setHasFlexibleArrayMember(true); 4973 } else if (!FDTy->isDependentType() && 4974 RequireCompleteType(FD->getLocation(), FD->getType(), 4975 diag::err_field_incomplete)) { 4976 // Incomplete type 4977 FD->setInvalidDecl(); 4978 EnclosingDecl->setInvalidDecl(); 4979 continue; 4980 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 4981 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4982 // If this is a member of a union, then entire union becomes "flexible". 4983 if (Record && Record->isUnion()) { 4984 Record->setHasFlexibleArrayMember(true); 4985 } else { 4986 // If this is a struct/class and this is not the last element, reject 4987 // it. Note that GCC supports variable sized arrays in the middle of 4988 // structures. 4989 if (i != NumFields-1) 4990 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4991 << FD->getDeclName() << FD->getType(); 4992 else { 4993 // We support flexible arrays at the end of structs in 4994 // other structs as an extension. 4995 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4996 << FD->getDeclName(); 4997 if (Record) 4998 Record->setHasFlexibleArrayMember(true); 4999 } 5000 } 5001 } 5002 if (Record && FDTTy->getDecl()->hasObjectMember()) 5003 Record->setHasObjectMember(true); 5004 } else if (FDTy->isObjCInterfaceType()) { 5005 /// A field cannot be an Objective-c object 5006 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5007 FD->setInvalidDecl(); 5008 EnclosingDecl->setInvalidDecl(); 5009 continue; 5010 } else if (getLangOptions().ObjC1 && 5011 getLangOptions().getGCMode() != LangOptions::NonGC && 5012 Record && 5013 (FD->getType()->isObjCObjectPointerType() || 5014 FD->getType().isObjCGCStrong())) 5015 Record->setHasObjectMember(true); 5016 // Keep track of the number of named members. 5017 if (FD->getIdentifier()) 5018 ++NumNamedMembers; 5019 } 5020 5021 // Okay, we successfully defined 'Record'. 5022 if (Record) { 5023 Record->completeDefinition(Context); 5024 } else { 5025 ObjCIvarDecl **ClsFields = 5026 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5027 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5028 ID->setIVarList(ClsFields, RecFields.size(), Context); 5029 ID->setLocEnd(RBrac); 5030 // Add ivar's to class's DeclContext. 5031 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5032 ClsFields[i]->setLexicalDeclContext(ID); 5033 ID->addDecl(ClsFields[i]); 5034 } 5035 // Must enforce the rule that ivars in the base classes may not be 5036 // duplicates. 5037 if (ID->getSuperClass()) { 5038 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5039 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5040 ObjCIvarDecl* Ivar = (*IVI); 5041 5042 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5043 ObjCIvarDecl* prevIvar = 5044 ID->getSuperClass()->lookupInstanceVariable(II); 5045 if (prevIvar) { 5046 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5047 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5048 } 5049 } 5050 } 5051 } 5052 } else if (ObjCImplementationDecl *IMPDecl = 5053 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5054 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5055 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5056 // Ivar declared in @implementation never belongs to the implementation. 5057 // Only it is in implementation's lexical context. 5058 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5059 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5060 } 5061 } 5062 5063 if (Attr) 5064 ProcessDeclAttributeList(S, Record, Attr); 5065} 5066 5067EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5068 EnumConstantDecl *LastEnumConst, 5069 SourceLocation IdLoc, 5070 IdentifierInfo *Id, 5071 ExprArg val) { 5072 Expr *Val = (Expr *)val.get(); 5073 5074 llvm::APSInt EnumVal(32); 5075 QualType EltTy; 5076 if (Val && !Val->isTypeDependent()) { 5077 // Make sure to promote the operand type to int. 5078 UsualUnaryConversions(Val); 5079 if (Val != val.get()) { 5080 val.release(); 5081 val = Val; 5082 } 5083 5084 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5085 SourceLocation ExpLoc; 5086 if (!Val->isValueDependent() && 5087 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5088 Val = 0; 5089 } else { 5090 EltTy = Val->getType(); 5091 } 5092 } 5093 5094 if (!Val) { 5095 if (LastEnumConst) { 5096 // Assign the last value + 1. 5097 EnumVal = LastEnumConst->getInitVal(); 5098 ++EnumVal; 5099 5100 // Check for overflow on increment. 5101 if (EnumVal < LastEnumConst->getInitVal()) 5102 Diag(IdLoc, diag::warn_enum_value_overflow); 5103 5104 EltTy = LastEnumConst->getType(); 5105 } else { 5106 // First value, set to zero. 5107 EltTy = Context.IntTy; 5108 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5109 } 5110 } 5111 5112 val.release(); 5113 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5114 Val, EnumVal); 5115} 5116 5117 5118Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5119 DeclPtrTy lastEnumConst, 5120 SourceLocation IdLoc, 5121 IdentifierInfo *Id, 5122 SourceLocation EqualLoc, ExprTy *val) { 5123 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5124 EnumConstantDecl *LastEnumConst = 5125 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5126 Expr *Val = static_cast<Expr*>(val); 5127 5128 // The scope passed in may not be a decl scope. Zip up the scope tree until 5129 // we find one that is. 5130 S = getNonFieldDeclScope(S); 5131 5132 // Verify that there isn't already something declared with this name in this 5133 // scope. 5134 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5135 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5136 // Maybe we will complain about the shadowed template parameter. 5137 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5138 // Just pretend that we didn't see the previous declaration. 5139 PrevDecl = 0; 5140 } 5141 5142 if (PrevDecl) { 5143 // When in C++, we may get a TagDecl with the same name; in this case the 5144 // enum constant will 'hide' the tag. 5145 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5146 "Received TagDecl when not in C++!"); 5147 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5148 if (isa<EnumConstantDecl>(PrevDecl)) 5149 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5150 else 5151 Diag(IdLoc, diag::err_redefinition) << Id; 5152 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5153 if (Val) Val->Destroy(Context); 5154 return DeclPtrTy(); 5155 } 5156 } 5157 5158 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5159 IdLoc, Id, Owned(Val)); 5160 5161 // Register this decl in the current scope stack. 5162 if (New) 5163 PushOnScopeChains(New, S); 5164 5165 return DeclPtrTy::make(New); 5166} 5167 5168void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5169 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5170 DeclPtrTy *Elements, unsigned NumElements, 5171 Scope *S, AttributeList *Attr) { 5172 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5173 QualType EnumType = Context.getTypeDeclType(Enum); 5174 5175 if (Attr) 5176 ProcessDeclAttributeList(S, Enum, Attr); 5177 5178 // TODO: If the result value doesn't fit in an int, it must be a long or long 5179 // long value. ISO C does not support this, but GCC does as an extension, 5180 // emit a warning. 5181 unsigned IntWidth = Context.Target.getIntWidth(); 5182 unsigned CharWidth = Context.Target.getCharWidth(); 5183 unsigned ShortWidth = Context.Target.getShortWidth(); 5184 5185 // Verify that all the values are okay, compute the size of the values, and 5186 // reverse the list. 5187 unsigned NumNegativeBits = 0; 5188 unsigned NumPositiveBits = 0; 5189 5190 // Keep track of whether all elements have type int. 5191 bool AllElementsInt = true; 5192 5193 for (unsigned i = 0; i != NumElements; ++i) { 5194 EnumConstantDecl *ECD = 5195 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5196 if (!ECD) continue; // Already issued a diagnostic. 5197 5198 // If the enum value doesn't fit in an int, emit an extension warning. 5199 const llvm::APSInt &InitVal = ECD->getInitVal(); 5200 assert(InitVal.getBitWidth() >= IntWidth && 5201 "Should have promoted value to int"); 5202 if (InitVal.getBitWidth() > IntWidth) { 5203 llvm::APSInt V(InitVal); 5204 V.trunc(IntWidth); 5205 V.extend(InitVal.getBitWidth()); 5206 if (V != InitVal) 5207 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5208 << InitVal.toString(10); 5209 } 5210 5211 // Keep track of the size of positive and negative values. 5212 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5213 NumPositiveBits = std::max(NumPositiveBits, 5214 (unsigned)InitVal.getActiveBits()); 5215 else 5216 NumNegativeBits = std::max(NumNegativeBits, 5217 (unsigned)InitVal.getMinSignedBits()); 5218 5219 // Keep track of whether every enum element has type int (very commmon). 5220 if (AllElementsInt) 5221 AllElementsInt = ECD->getType() == Context.IntTy; 5222 } 5223 5224 // Figure out the type that should be used for this enum. 5225 // FIXME: Support -fshort-enums. 5226 QualType BestType; 5227 unsigned BestWidth; 5228 5229 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5230 5231 if (NumNegativeBits) { 5232 // If there is a negative value, figure out the smallest integer type (of 5233 // int/long/longlong) that fits. 5234 // If it's packed, check also if it fits a char or a short. 5235 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5236 BestType = Context.SignedCharTy; 5237 BestWidth = CharWidth; 5238 } else if (Packed && NumNegativeBits <= ShortWidth && 5239 NumPositiveBits < ShortWidth) { 5240 BestType = Context.ShortTy; 5241 BestWidth = ShortWidth; 5242 } 5243 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5244 BestType = Context.IntTy; 5245 BestWidth = IntWidth; 5246 } else { 5247 BestWidth = Context.Target.getLongWidth(); 5248 5249 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5250 BestType = Context.LongTy; 5251 else { 5252 BestWidth = Context.Target.getLongLongWidth(); 5253 5254 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5255 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5256 BestType = Context.LongLongTy; 5257 } 5258 } 5259 } else { 5260 // If there is no negative value, figure out which of uint, ulong, ulonglong 5261 // fits. 5262 // If it's packed, check also if it fits a char or a short. 5263 if (Packed && NumPositiveBits <= CharWidth) { 5264 BestType = Context.UnsignedCharTy; 5265 BestWidth = CharWidth; 5266 } else if (Packed && NumPositiveBits <= ShortWidth) { 5267 BestType = Context.UnsignedShortTy; 5268 BestWidth = ShortWidth; 5269 } 5270 else if (NumPositiveBits <= IntWidth) { 5271 BestType = Context.UnsignedIntTy; 5272 BestWidth = IntWidth; 5273 } else if (NumPositiveBits <= 5274 (BestWidth = Context.Target.getLongWidth())) { 5275 BestType = Context.UnsignedLongTy; 5276 } else { 5277 BestWidth = Context.Target.getLongLongWidth(); 5278 assert(NumPositiveBits <= BestWidth && 5279 "How could an initializer get larger than ULL?"); 5280 BestType = Context.UnsignedLongLongTy; 5281 } 5282 } 5283 5284 // Loop over all of the enumerator constants, changing their types to match 5285 // the type of the enum if needed. 5286 for (unsigned i = 0; i != NumElements; ++i) { 5287 EnumConstantDecl *ECD = 5288 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5289 if (!ECD) continue; // Already issued a diagnostic. 5290 5291 // Standard C says the enumerators have int type, but we allow, as an 5292 // extension, the enumerators to be larger than int size. If each 5293 // enumerator value fits in an int, type it as an int, otherwise type it the 5294 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5295 // that X has type 'int', not 'unsigned'. 5296 if (ECD->getType() == Context.IntTy) { 5297 // Make sure the init value is signed. 5298 llvm::APSInt IV = ECD->getInitVal(); 5299 IV.setIsSigned(true); 5300 ECD->setInitVal(IV); 5301 5302 if (getLangOptions().CPlusPlus) 5303 // C++ [dcl.enum]p4: Following the closing brace of an 5304 // enum-specifier, each enumerator has the type of its 5305 // enumeration. 5306 ECD->setType(EnumType); 5307 continue; // Already int type. 5308 } 5309 5310 // Determine whether the value fits into an int. 5311 llvm::APSInt InitVal = ECD->getInitVal(); 5312 bool FitsInInt; 5313 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5314 FitsInInt = InitVal.getActiveBits() < IntWidth; 5315 else 5316 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5317 5318 // If it fits into an integer type, force it. Otherwise force it to match 5319 // the enum decl type. 5320 QualType NewTy; 5321 unsigned NewWidth; 5322 bool NewSign; 5323 if (FitsInInt) { 5324 NewTy = Context.IntTy; 5325 NewWidth = IntWidth; 5326 NewSign = true; 5327 } else if (ECD->getType() == BestType) { 5328 // Already the right type! 5329 if (getLangOptions().CPlusPlus) 5330 // C++ [dcl.enum]p4: Following the closing brace of an 5331 // enum-specifier, each enumerator has the type of its 5332 // enumeration. 5333 ECD->setType(EnumType); 5334 continue; 5335 } else { 5336 NewTy = BestType; 5337 NewWidth = BestWidth; 5338 NewSign = BestType->isSignedIntegerType(); 5339 } 5340 5341 // Adjust the APSInt value. 5342 InitVal.extOrTrunc(NewWidth); 5343 InitVal.setIsSigned(NewSign); 5344 ECD->setInitVal(InitVal); 5345 5346 // Adjust the Expr initializer and type. 5347 if (ECD->getInitExpr()) 5348 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5349 CastExpr::CK_Unknown, 5350 ECD->getInitExpr(), 5351 /*isLvalue=*/false)); 5352 if (getLangOptions().CPlusPlus) 5353 // C++ [dcl.enum]p4: Following the closing brace of an 5354 // enum-specifier, each enumerator has the type of its 5355 // enumeration. 5356 ECD->setType(EnumType); 5357 else 5358 ECD->setType(NewTy); 5359 } 5360 5361 Enum->completeDefinition(Context, BestType); 5362} 5363 5364Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5365 ExprArg expr) { 5366 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5367 5368 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5369 Loc, AsmString); 5370 CurContext->addDecl(New); 5371 return DeclPtrTy::make(New); 5372} 5373 5374void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5375 SourceLocation PragmaLoc, 5376 SourceLocation NameLoc) { 5377 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5378 5379 if (PrevDecl) { 5380 PrevDecl->addAttr(::new (Context) WeakAttr()); 5381 } else { 5382 (void)WeakUndeclaredIdentifiers.insert( 5383 std::pair<IdentifierInfo*,WeakInfo> 5384 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5385 } 5386} 5387 5388void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5389 IdentifierInfo* AliasName, 5390 SourceLocation PragmaLoc, 5391 SourceLocation NameLoc, 5392 SourceLocation AliasNameLoc) { 5393 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5394 WeakInfo W = WeakInfo(Name, NameLoc); 5395 5396 if (PrevDecl) { 5397 if (!PrevDecl->hasAttr<AliasAttr>()) 5398 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5399 DeclApplyPragmaWeak(TUScope, ND, W); 5400 } else { 5401 (void)WeakUndeclaredIdentifiers.insert( 5402 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5403 } 5404} 5405