SemaDecl.cpp revision 0b60d9e0097e2d6a1a5e62396967e207c4a772f2
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/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 525/// same name and scope as a previous declaration 'Old'. Figure out 526/// how to resolve this situation, merging decls or emitting 527/// diagnostics as appropriate. If there was an error, set New to be invalid. 528/// 529void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 530 // If either decl is known invalid already, set the new one to be invalid and 531 // don't bother doing any merging checks. 532 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 533 return New->setInvalidDecl(); 534 535 // Allow multiple definitions for ObjC built-in typedefs. 536 // FIXME: Verify the underlying types are equivalent! 537 if (getLangOptions().ObjC1) { 538 const IdentifierInfo *TypeID = New->getIdentifier(); 539 switch (TypeID->getLength()) { 540 default: break; 541 case 2: 542 if (!TypeID->isStr("id")) 543 break; 544 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 545 // Install the built-in type for 'id', ignoring the current definition. 546 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 547 return; 548 case 5: 549 if (!TypeID->isStr("Class")) 550 break; 551 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 552 // Install the built-in type for 'Class', ignoring the current definition. 553 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 554 return; 555 case 3: 556 if (!TypeID->isStr("SEL")) 557 break; 558 Context.setObjCSelType(Context.getTypeDeclType(New)); 559 return; 560 case 8: 561 if (!TypeID->isStr("Protocol")) 562 break; 563 Context.setObjCProtoType(New->getUnderlyingType()); 564 return; 565 } 566 // Fall through - the typedef name was not a builtin type. 567 } 568 // Verify the old decl was also a type. 569 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 570 if (!Old) { 571 Diag(New->getLocation(), diag::err_redefinition_different_kind) 572 << New->getDeclName(); 573 if (OldD->getLocation().isValid()) 574 Diag(OldD->getLocation(), diag::note_previous_definition); 575 return New->setInvalidDecl(); 576 } 577 578 // Determine the "old" type we'll use for checking and diagnostics. 579 QualType OldType; 580 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 581 OldType = OldTypedef->getUnderlyingType(); 582 else 583 OldType = Context.getTypeDeclType(Old); 584 585 // If the typedef types are not identical, reject them in all languages and 586 // with any extensions enabled. 587 588 if (OldType != New->getUnderlyingType() && 589 Context.getCanonicalType(OldType) != 590 Context.getCanonicalType(New->getUnderlyingType())) { 591 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 592 << New->getUnderlyingType() << OldType; 593 if (Old->getLocation().isValid()) 594 Diag(Old->getLocation(), diag::note_previous_definition); 595 return New->setInvalidDecl(); 596 } 597 598 if (getLangOptions().Microsoft) 599 return; 600 601 // C++ [dcl.typedef]p2: 602 // In a given non-class scope, a typedef specifier can be used to 603 // redefine the name of any type declared in that scope to refer 604 // to the type to which it already refers. 605 if (getLangOptions().CPlusPlus) { 606 if (!isa<CXXRecordDecl>(CurContext)) 607 return; 608 Diag(New->getLocation(), diag::err_redefinition) 609 << New->getDeclName(); 610 Diag(Old->getLocation(), diag::note_previous_definition); 611 return New->setInvalidDecl(); 612 } 613 614 // If we have a redefinition of a typedef in C, emit a warning. This warning 615 // is normally mapped to an error, but can be controlled with 616 // -Wtypedef-redefinition. If either the original or the redefinition is 617 // in a system header, don't emit this for compatibility with GCC. 618 if (PP.getDiagnostics().getSuppressSystemWarnings() && 619 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 620 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 621 return; 622 623 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 624 << New->getDeclName(); 625 Diag(Old->getLocation(), diag::note_previous_definition); 626 return; 627} 628 629/// DeclhasAttr - returns true if decl Declaration already has the target 630/// attribute. 631static bool 632DeclHasAttr(const Decl *decl, const Attr *target) { 633 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 634 if (attr->getKind() == target->getKind()) 635 return true; 636 637 return false; 638} 639 640/// MergeAttributes - append attributes from the Old decl to the New one. 641static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 642 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 643 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 644 Attr *NewAttr = attr->clone(C); 645 NewAttr->setInherited(true); 646 New->addAttr(NewAttr); 647 } 648 } 649} 650 651/// Used in MergeFunctionDecl to keep track of function parameters in 652/// C. 653struct GNUCompatibleParamWarning { 654 ParmVarDecl *OldParm; 655 ParmVarDecl *NewParm; 656 QualType PromotedType; 657}; 658 659/// MergeFunctionDecl - We just parsed a function 'New' from 660/// declarator D which has the same name and scope as a previous 661/// declaration 'Old'. Figure out how to resolve this situation, 662/// merging decls or emitting diagnostics as appropriate. 663/// 664/// In C++, New and Old must be declarations that are not 665/// overloaded. Use IsOverload to determine whether New and Old are 666/// overloaded, and to select the Old declaration that New should be 667/// merged with. 668/// 669/// Returns true if there was an error, false otherwise. 670bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 671 assert(!isa<OverloadedFunctionDecl>(OldD) && 672 "Cannot merge with an overloaded function declaration"); 673 674 // Verify the old decl was also a function. 675 FunctionDecl *Old = 0; 676 if (FunctionTemplateDecl *OldFunctionTemplate 677 = dyn_cast<FunctionTemplateDecl>(OldD)) 678 Old = OldFunctionTemplate->getTemplatedDecl(); 679 else 680 Old = dyn_cast<FunctionDecl>(OldD); 681 if (!Old) { 682 Diag(New->getLocation(), diag::err_redefinition_different_kind) 683 << New->getDeclName(); 684 Diag(OldD->getLocation(), diag::note_previous_definition); 685 return true; 686 } 687 688 // Determine whether the previous declaration was a definition, 689 // implicit declaration, or a declaration. 690 diag::kind PrevDiag; 691 if (Old->isThisDeclarationADefinition()) 692 PrevDiag = diag::note_previous_definition; 693 else if (Old->isImplicit()) 694 PrevDiag = diag::note_previous_implicit_declaration; 695 else 696 PrevDiag = diag::note_previous_declaration; 697 698 QualType OldQType = Context.getCanonicalType(Old->getType()); 699 QualType NewQType = Context.getCanonicalType(New->getType()); 700 701 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 702 New->getStorageClass() == FunctionDecl::Static && 703 Old->getStorageClass() != FunctionDecl::Static) { 704 Diag(New->getLocation(), diag::err_static_non_static) 705 << New; 706 Diag(Old->getLocation(), PrevDiag); 707 return true; 708 } 709 710 if (getLangOptions().CPlusPlus) { 711 // (C++98 13.1p2): 712 // Certain function declarations cannot be overloaded: 713 // -- Function declarations that differ only in the return type 714 // cannot be overloaded. 715 QualType OldReturnType 716 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 717 QualType NewReturnType 718 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 719 if (OldReturnType != NewReturnType) { 720 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 721 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 722 return true; 723 } 724 725 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 726 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 727 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 728 NewMethod->getLexicalDeclContext()->isRecord()) { 729 // -- Member function declarations with the same name and the 730 // same parameter types cannot be overloaded if any of them 731 // is a static member function declaration. 732 if (OldMethod->isStatic() || NewMethod->isStatic()) { 733 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 734 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 735 return true; 736 } 737 738 // C++ [class.mem]p1: 739 // [...] A member shall not be declared twice in the 740 // member-specification, except that a nested class or member 741 // class template can be declared and then later defined. 742 unsigned NewDiag; 743 if (isa<CXXConstructorDecl>(OldMethod)) 744 NewDiag = diag::err_constructor_redeclared; 745 else if (isa<CXXDestructorDecl>(NewMethod)) 746 NewDiag = diag::err_destructor_redeclared; 747 else if (isa<CXXConversionDecl>(NewMethod)) 748 NewDiag = diag::err_conv_function_redeclared; 749 else 750 NewDiag = diag::err_member_redeclared; 751 752 Diag(New->getLocation(), NewDiag); 753 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 754 } 755 756 // (C++98 8.3.5p3): 757 // All declarations for a function shall agree exactly in both the 758 // return type and the parameter-type-list. 759 if (OldQType == NewQType) 760 return MergeCompatibleFunctionDecls(New, Old); 761 762 // Fall through for conflicting redeclarations and redefinitions. 763 } 764 765 // C: Function types need to be compatible, not identical. This handles 766 // duplicate function decls like "void f(int); void f(enum X);" properly. 767 if (!getLangOptions().CPlusPlus && 768 Context.typesAreCompatible(OldQType, NewQType)) { 769 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 770 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 771 const FunctionProtoType *OldProto = 0; 772 if (isa<FunctionNoProtoType>(NewFuncType) && 773 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 774 // The old declaration provided a function prototype, but the 775 // new declaration does not. Merge in the prototype. 776 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 777 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 778 OldProto->arg_type_end()); 779 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 780 ParamTypes.data(), ParamTypes.size(), 781 OldProto->isVariadic(), 782 OldProto->getTypeQuals()); 783 New->setType(NewQType); 784 New->setHasInheritedPrototype(); 785 786 // Synthesize a parameter for each argument type. 787 llvm::SmallVector<ParmVarDecl*, 16> Params; 788 for (FunctionProtoType::arg_type_iterator 789 ParamType = OldProto->arg_type_begin(), 790 ParamEnd = OldProto->arg_type_end(); 791 ParamType != ParamEnd; ++ParamType) { 792 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 793 SourceLocation(), 0, 794 *ParamType, /*DInfo=*/0, 795 VarDecl::None, 0); 796 Param->setImplicit(); 797 Params.push_back(Param); 798 } 799 800 New->setParams(Context, Params.data(), Params.size()); 801 } 802 803 return MergeCompatibleFunctionDecls(New, Old); 804 } 805 806 // GNU C permits a K&R definition to follow a prototype declaration 807 // if the declared types of the parameters in the K&R definition 808 // match the types in the prototype declaration, even when the 809 // promoted types of the parameters from the K&R definition differ 810 // from the types in the prototype. GCC then keeps the types from 811 // the prototype. 812 // 813 // If a variadic prototype is followed by a non-variadic K&R definition, 814 // the K&R definition becomes variadic. This is sort of an edge case, but 815 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 816 // C99 6.9.1p8. 817 if (!getLangOptions().CPlusPlus && 818 Old->hasPrototype() && !New->hasPrototype() && 819 New->getType()->getAs<FunctionProtoType>() && 820 Old->getNumParams() == New->getNumParams()) { 821 llvm::SmallVector<QualType, 16> ArgTypes; 822 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 823 const FunctionProtoType *OldProto 824 = Old->getType()->getAs<FunctionProtoType>(); 825 const FunctionProtoType *NewProto 826 = New->getType()->getAs<FunctionProtoType>(); 827 828 // Determine whether this is the GNU C extension. 829 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 830 NewProto->getResultType()); 831 bool LooseCompatible = !MergedReturn.isNull(); 832 for (unsigned Idx = 0, End = Old->getNumParams(); 833 LooseCompatible && Idx != End; ++Idx) { 834 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 835 ParmVarDecl *NewParm = New->getParamDecl(Idx); 836 if (Context.typesAreCompatible(OldParm->getType(), 837 NewProto->getArgType(Idx))) { 838 ArgTypes.push_back(NewParm->getType()); 839 } else if (Context.typesAreCompatible(OldParm->getType(), 840 NewParm->getType())) { 841 GNUCompatibleParamWarning Warn 842 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 843 Warnings.push_back(Warn); 844 ArgTypes.push_back(NewParm->getType()); 845 } else 846 LooseCompatible = false; 847 } 848 849 if (LooseCompatible) { 850 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 851 Diag(Warnings[Warn].NewParm->getLocation(), 852 diag::ext_param_promoted_not_compatible_with_prototype) 853 << Warnings[Warn].PromotedType 854 << Warnings[Warn].OldParm->getType(); 855 Diag(Warnings[Warn].OldParm->getLocation(), 856 diag::note_previous_declaration); 857 } 858 859 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 860 ArgTypes.size(), 861 OldProto->isVariadic(), 0)); 862 return MergeCompatibleFunctionDecls(New, Old); 863 } 864 865 // Fall through to diagnose conflicting types. 866 } 867 868 // A function that has already been declared has been redeclared or defined 869 // with a different type- show appropriate diagnostic 870 if (unsigned BuiltinID = Old->getBuiltinID()) { 871 // The user has declared a builtin function with an incompatible 872 // signature. 873 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 874 // The function the user is redeclaring is a library-defined 875 // function like 'malloc' or 'printf'. Warn about the 876 // redeclaration, then pretend that we don't know about this 877 // library built-in. 878 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 879 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 880 << Old << Old->getType(); 881 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 882 Old->setInvalidDecl(); 883 return false; 884 } 885 886 PrevDiag = diag::note_previous_builtin_declaration; 887 } 888 889 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 890 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 891 return true; 892} 893 894/// \brief Completes the merge of two function declarations that are 895/// known to be compatible. 896/// 897/// This routine handles the merging of attributes and other 898/// properties of function declarations form the old declaration to 899/// the new declaration, once we know that New is in fact a 900/// redeclaration of Old. 901/// 902/// \returns false 903bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 904 // Merge the attributes 905 MergeAttributes(New, Old, Context); 906 907 // Merge the storage class. 908 if (Old->getStorageClass() != FunctionDecl::Extern && 909 Old->getStorageClass() != FunctionDecl::None) 910 New->setStorageClass(Old->getStorageClass()); 911 912 // Merge "pure" flag. 913 if (Old->isPure()) 914 New->setPure(); 915 916 // Merge the "deleted" flag. 917 if (Old->isDeleted()) 918 New->setDeleted(); 919 920 if (getLangOptions().CPlusPlus) 921 return MergeCXXFunctionDecl(New, Old); 922 923 return false; 924} 925 926/// MergeVarDecl - We just parsed a variable 'New' which has the same name 927/// and scope as a previous declaration 'Old'. Figure out how to resolve this 928/// situation, merging decls or emitting diagnostics as appropriate. 929/// 930/// Tentative definition rules (C99 6.9.2p2) are checked by 931/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 932/// definitions here, since the initializer hasn't been attached. 933/// 934void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 935 // If either decl is invalid, make sure the new one is marked invalid and 936 // don't do any other checking. 937 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 938 return New->setInvalidDecl(); 939 940 // Verify the old decl was also a variable. 941 VarDecl *Old = dyn_cast<VarDecl>(OldD); 942 if (!Old) { 943 Diag(New->getLocation(), diag::err_redefinition_different_kind) 944 << New->getDeclName(); 945 Diag(OldD->getLocation(), diag::note_previous_definition); 946 return New->setInvalidDecl(); 947 } 948 949 MergeAttributes(New, Old, Context); 950 951 // Merge the types 952 QualType MergedT; 953 if (getLangOptions().CPlusPlus) { 954 if (Context.hasSameType(New->getType(), Old->getType())) 955 MergedT = New->getType(); 956 // C++ [basic.types]p7: 957 // [...] The declared type of an array object might be an array of 958 // unknown size and therefore be incomplete at one point in a 959 // translation unit and complete later on; [...] 960 else if (Old->getType()->isIncompleteArrayType() && 961 New->getType()->isArrayType()) { 962 CanQual<ArrayType> OldArray 963 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 964 CanQual<ArrayType> NewArray 965 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 966 if (OldArray->getElementType() == NewArray->getElementType()) 967 MergedT = New->getType(); 968 } 969 } else { 970 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 971 } 972 if (MergedT.isNull()) { 973 Diag(New->getLocation(), diag::err_redefinition_different_type) 974 << New->getDeclName(); 975 Diag(Old->getLocation(), diag::note_previous_definition); 976 return New->setInvalidDecl(); 977 } 978 New->setType(MergedT); 979 980 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 981 if (New->getStorageClass() == VarDecl::Static && 982 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 983 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 984 Diag(Old->getLocation(), diag::note_previous_definition); 985 return New->setInvalidDecl(); 986 } 987 // C99 6.2.2p4: 988 // For an identifier declared with the storage-class specifier 989 // extern in a scope in which a prior declaration of that 990 // identifier is visible,23) if the prior declaration specifies 991 // internal or external linkage, the linkage of the identifier at 992 // the later declaration is the same as the linkage specified at 993 // the prior declaration. If no prior declaration is visible, or 994 // if the prior declaration specifies no linkage, then the 995 // identifier has external linkage. 996 if (New->hasExternalStorage() && Old->hasLinkage()) 997 /* Okay */; 998 else if (New->getStorageClass() != VarDecl::Static && 999 Old->getStorageClass() == VarDecl::Static) { 1000 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1001 Diag(Old->getLocation(), diag::note_previous_definition); 1002 return New->setInvalidDecl(); 1003 } 1004 1005 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1006 1007 // FIXME: The test for external storage here seems wrong? We still 1008 // need to check for mismatches. 1009 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1010 // Don't complain about out-of-line definitions of static members. 1011 !(Old->getLexicalDeclContext()->isRecord() && 1012 !New->getLexicalDeclContext()->isRecord())) { 1013 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1014 Diag(Old->getLocation(), diag::note_previous_definition); 1015 return New->setInvalidDecl(); 1016 } 1017 1018 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1019 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1020 Diag(Old->getLocation(), diag::note_previous_definition); 1021 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1022 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1023 Diag(Old->getLocation(), diag::note_previous_definition); 1024 } 1025 1026 // Keep a chain of previous declarations. 1027 New->setPreviousDeclaration(Old); 1028} 1029 1030/// CheckFallThrough - Check that we don't fall off the end of a 1031/// Statement that should return a value. 1032/// 1033/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1034/// MaybeFallThrough iff we might or might not fall off the end and 1035/// NeverFallThrough iff we never fall off the end of the statement. We assume 1036/// that functions not marked noreturn will return. 1037Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1038 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1039 1040 // FIXME: They should never return 0, fix that, delete this code. 1041 if (cfg == 0) 1042 return NeverFallThrough; 1043 // The CFG leaves in dead things, and we don't want to dead code paths to 1044 // confuse us, so we mark all live things first. 1045 std::queue<CFGBlock*> workq; 1046 llvm::BitVector live(cfg->getNumBlockIDs()); 1047 // Prep work queue 1048 workq.push(&cfg->getEntry()); 1049 // Solve 1050 while (!workq.empty()) { 1051 CFGBlock *item = workq.front(); 1052 workq.pop(); 1053 live.set(item->getBlockID()); 1054 for (CFGBlock::succ_iterator I=item->succ_begin(), 1055 E=item->succ_end(); 1056 I != E; 1057 ++I) { 1058 if ((*I) && !live[(*I)->getBlockID()]) { 1059 live.set((*I)->getBlockID()); 1060 workq.push(*I); 1061 } 1062 } 1063 } 1064 1065 // Now we know what is live, we check the live precessors of the exit block 1066 // and look for fall through paths, being careful to ignore normal returns, 1067 // and exceptional paths. 1068 bool HasLiveReturn = false; 1069 bool HasFakeEdge = false; 1070 bool HasPlainEdge = false; 1071 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1072 E = cfg->getExit().pred_end(); 1073 I != E; 1074 ++I) { 1075 CFGBlock& B = **I; 1076 if (!live[B.getBlockID()]) 1077 continue; 1078 if (B.size() == 0) { 1079 // A labeled empty statement, or the entry block... 1080 HasPlainEdge = true; 1081 continue; 1082 } 1083 Stmt *S = B[B.size()-1]; 1084 if (isa<ReturnStmt>(S)) { 1085 HasLiveReturn = true; 1086 continue; 1087 } 1088 if (isa<ObjCAtThrowStmt>(S)) { 1089 HasFakeEdge = true; 1090 continue; 1091 } 1092 if (isa<CXXThrowExpr>(S)) { 1093 HasFakeEdge = true; 1094 continue; 1095 } 1096 bool NoReturnEdge = false; 1097 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1098 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1099 if (CEE->getType().getNoReturnAttr()) { 1100 NoReturnEdge = true; 1101 HasFakeEdge = true; 1102 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1103 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1104 if (FD->hasAttr<NoReturnAttr>()) { 1105 NoReturnEdge = true; 1106 HasFakeEdge = true; 1107 } 1108 } 1109 } 1110 } 1111 // FIXME: Add noreturn message sends. 1112 if (NoReturnEdge == false) 1113 HasPlainEdge = true; 1114 } 1115 if (!HasPlainEdge) 1116 return NeverFallThrough; 1117 if (HasFakeEdge || HasLiveReturn) 1118 return MaybeFallThrough; 1119 // This says AlwaysFallThrough for calls to functions that are not marked 1120 // noreturn, that don't return. If people would like this warning to be more 1121 // accurate, such functions should be marked as noreturn. 1122 return AlwaysFallThrough; 1123} 1124 1125/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1126/// function that should return a value. Check that we don't fall off the end 1127/// of a noreturn function. We assume that functions and blocks not marked 1128/// noreturn will return. 1129void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1130 // FIXME: Would be nice if we had a better way to control cascading errors, 1131 // but for now, avoid them. The problem is that when Parse sees: 1132 // int foo() { return a; } 1133 // The return is eaten and the Sema code sees just: 1134 // int foo() { } 1135 // which this code would then warn about. 1136 if (getDiagnostics().hasErrorOccurred()) 1137 return; 1138 bool ReturnsVoid = false; 1139 bool HasNoReturn = false; 1140 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1141 if (FD->getResultType()->isVoidType()) 1142 ReturnsVoid = true; 1143 if (FD->hasAttr<NoReturnAttr>()) 1144 HasNoReturn = true; 1145 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1146 if (MD->getResultType()->isVoidType()) 1147 ReturnsVoid = true; 1148 if (MD->hasAttr<NoReturnAttr>()) 1149 HasNoReturn = true; 1150 } 1151 1152 // Short circuit for compilation speed. 1153 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1154 == Diagnostic::Ignored || ReturnsVoid) 1155 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1156 == Diagnostic::Ignored || !HasNoReturn) 1157 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1158 == Diagnostic::Ignored || !ReturnsVoid)) 1159 return; 1160 // FIXME: Funtion try block 1161 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1162 switch (CheckFallThrough(Body)) { 1163 case MaybeFallThrough: 1164 if (HasNoReturn) 1165 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1166 else if (!ReturnsVoid) 1167 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1168 break; 1169 case AlwaysFallThrough: 1170 if (HasNoReturn) 1171 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1172 else if (!ReturnsVoid) 1173 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1174 break; 1175 case NeverFallThrough: 1176 if (ReturnsVoid) 1177 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1178 break; 1179 } 1180 } 1181} 1182 1183/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1184/// that should return a value. Check that we don't fall off the end of a 1185/// noreturn block. We assume that functions and blocks not marked noreturn 1186/// will return. 1187void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1188 // FIXME: Would be nice if we had a better way to control cascading errors, 1189 // but for now, avoid them. The problem is that when Parse sees: 1190 // int foo() { return a; } 1191 // The return is eaten and the Sema code sees just: 1192 // int foo() { } 1193 // which this code would then warn about. 1194 if (getDiagnostics().hasErrorOccurred()) 1195 return; 1196 bool ReturnsVoid = false; 1197 bool HasNoReturn = false; 1198 if (const FunctionType *FT = BlockTy->getPointeeType()->getAs<FunctionType>()) { 1199 if (FT->getResultType()->isVoidType()) 1200 ReturnsVoid = true; 1201 if (FT->getNoReturnAttr()) 1202 HasNoReturn = true; 1203 } 1204 1205 // Short circuit for compilation speed. 1206 if (ReturnsVoid 1207 && !HasNoReturn 1208 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1209 == Diagnostic::Ignored || !ReturnsVoid)) 1210 return; 1211 // FIXME: Funtion try block 1212 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1213 switch (CheckFallThrough(Body)) { 1214 case MaybeFallThrough: 1215 if (HasNoReturn) 1216 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1217 else if (!ReturnsVoid) 1218 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1219 break; 1220 case AlwaysFallThrough: 1221 if (HasNoReturn) 1222 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1223 else if (!ReturnsVoid) 1224 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1225 break; 1226 case NeverFallThrough: 1227 if (ReturnsVoid) 1228 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1229 break; 1230 } 1231 } 1232} 1233 1234/// CheckParmsForFunctionDef - Check that the parameters of the given 1235/// function are appropriate for the definition of a function. This 1236/// takes care of any checks that cannot be performed on the 1237/// declaration itself, e.g., that the types of each of the function 1238/// parameters are complete. 1239bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1240 bool HasInvalidParm = false; 1241 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1242 ParmVarDecl *Param = FD->getParamDecl(p); 1243 1244 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1245 // function declarator that is part of a function definition of 1246 // that function shall not have incomplete type. 1247 // 1248 // This is also C++ [dcl.fct]p6. 1249 if (!Param->isInvalidDecl() && 1250 RequireCompleteType(Param->getLocation(), Param->getType(), 1251 diag::err_typecheck_decl_incomplete_type)) { 1252 Param->setInvalidDecl(); 1253 HasInvalidParm = true; 1254 } 1255 1256 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1257 // declaration of each parameter shall include an identifier. 1258 if (Param->getIdentifier() == 0 && 1259 !Param->isImplicit() && 1260 !getLangOptions().CPlusPlus) 1261 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1262 } 1263 1264 return HasInvalidParm; 1265} 1266 1267/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1268/// no declarator (e.g. "struct foo;") is parsed. 1269Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1270 // FIXME: Error on auto/register at file scope 1271 // FIXME: Error on inline/virtual/explicit 1272 // FIXME: Error on invalid restrict 1273 // FIXME: Warn on useless __thread 1274 // FIXME: Warn on useless const/volatile 1275 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1276 // FIXME: Warn on useless attributes 1277 TagDecl *Tag = 0; 1278 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1279 DS.getTypeSpecType() == DeclSpec::TST_struct || 1280 DS.getTypeSpecType() == DeclSpec::TST_union || 1281 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1282 if (!DS.getTypeRep()) // We probably had an error 1283 return DeclPtrTy(); 1284 1285 // Note that the above type specs guarantee that the 1286 // type rep is a Decl, whereas in many of the others 1287 // it's a Type. 1288 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1289 } 1290 1291 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1292 if (!Record->getDeclName() && Record->isDefinition() && 1293 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1294 if (getLangOptions().CPlusPlus || 1295 Record->getDeclContext()->isRecord()) 1296 return BuildAnonymousStructOrUnion(S, DS, Record); 1297 1298 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1299 << DS.getSourceRange(); 1300 } 1301 1302 // Microsoft allows unnamed struct/union fields. Don't complain 1303 // about them. 1304 // FIXME: Should we support Microsoft's extensions in this area? 1305 if (Record->getDeclName() && getLangOptions().Microsoft) 1306 return DeclPtrTy::make(Tag); 1307 } 1308 1309 if (!DS.isMissingDeclaratorOk() && 1310 DS.getTypeSpecType() != DeclSpec::TST_error) { 1311 // Warn about typedefs of enums without names, since this is an 1312 // extension in both Microsoft an GNU. 1313 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1314 Tag && isa<EnumDecl>(Tag)) { 1315 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1316 << DS.getSourceRange(); 1317 return DeclPtrTy::make(Tag); 1318 } 1319 1320 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1321 << DS.getSourceRange(); 1322 return DeclPtrTy(); 1323 } 1324 1325 return DeclPtrTy::make(Tag); 1326} 1327 1328/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1329/// anonymous struct or union AnonRecord into the owning context Owner 1330/// and scope S. This routine will be invoked just after we realize 1331/// that an unnamed union or struct is actually an anonymous union or 1332/// struct, e.g., 1333/// 1334/// @code 1335/// union { 1336/// int i; 1337/// float f; 1338/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1339/// // f into the surrounding scope.x 1340/// @endcode 1341/// 1342/// This routine is recursive, injecting the names of nested anonymous 1343/// structs/unions into the owning context and scope as well. 1344bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1345 RecordDecl *AnonRecord) { 1346 bool Invalid = false; 1347 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1348 FEnd = AnonRecord->field_end(); 1349 F != FEnd; ++F) { 1350 if ((*F)->getDeclName()) { 1351 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1352 LookupOrdinaryName, true); 1353 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1354 // C++ [class.union]p2: 1355 // The names of the members of an anonymous union shall be 1356 // distinct from the names of any other entity in the 1357 // scope in which the anonymous union is declared. 1358 unsigned diagKind 1359 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1360 : diag::err_anonymous_struct_member_redecl; 1361 Diag((*F)->getLocation(), diagKind) 1362 << (*F)->getDeclName(); 1363 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1364 Invalid = true; 1365 } else { 1366 // C++ [class.union]p2: 1367 // For the purpose of name lookup, after the anonymous union 1368 // definition, the members of the anonymous union are 1369 // considered to have been defined in the scope in which the 1370 // anonymous union is declared. 1371 Owner->makeDeclVisibleInContext(*F); 1372 S->AddDecl(DeclPtrTy::make(*F)); 1373 IdResolver.AddDecl(*F); 1374 } 1375 } else if (const RecordType *InnerRecordType 1376 = (*F)->getType()->getAs<RecordType>()) { 1377 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1378 if (InnerRecord->isAnonymousStructOrUnion()) 1379 Invalid = Invalid || 1380 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1381 } 1382 } 1383 1384 return Invalid; 1385} 1386 1387/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1388/// anonymous structure or union. Anonymous unions are a C++ feature 1389/// (C++ [class.union]) and a GNU C extension; anonymous structures 1390/// are a GNU C and GNU C++ extension. 1391Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1392 RecordDecl *Record) { 1393 DeclContext *Owner = Record->getDeclContext(); 1394 1395 // Diagnose whether this anonymous struct/union is an extension. 1396 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1397 Diag(Record->getLocation(), diag::ext_anonymous_union); 1398 else if (!Record->isUnion()) 1399 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1400 1401 // C and C++ require different kinds of checks for anonymous 1402 // structs/unions. 1403 bool Invalid = false; 1404 if (getLangOptions().CPlusPlus) { 1405 const char* PrevSpec = 0; 1406 unsigned DiagID; 1407 // C++ [class.union]p3: 1408 // Anonymous unions declared in a named namespace or in the 1409 // global namespace shall be declared static. 1410 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1411 (isa<TranslationUnitDecl>(Owner) || 1412 (isa<NamespaceDecl>(Owner) && 1413 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1414 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1415 Invalid = true; 1416 1417 // Recover by adding 'static'. 1418 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1419 PrevSpec, DiagID); 1420 } 1421 // C++ [class.union]p3: 1422 // A storage class is not allowed in a declaration of an 1423 // anonymous union in a class scope. 1424 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1425 isa<RecordDecl>(Owner)) { 1426 Diag(DS.getStorageClassSpecLoc(), 1427 diag::err_anonymous_union_with_storage_spec); 1428 Invalid = true; 1429 1430 // Recover by removing the storage specifier. 1431 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1432 PrevSpec, DiagID); 1433 } 1434 1435 // C++ [class.union]p2: 1436 // The member-specification of an anonymous union shall only 1437 // define non-static data members. [Note: nested types and 1438 // functions cannot be declared within an anonymous union. ] 1439 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1440 MemEnd = Record->decls_end(); 1441 Mem != MemEnd; ++Mem) { 1442 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1443 // C++ [class.union]p3: 1444 // An anonymous union shall not have private or protected 1445 // members (clause 11). 1446 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1447 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1448 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1449 Invalid = true; 1450 } 1451 } else if ((*Mem)->isImplicit()) { 1452 // Any implicit members are fine. 1453 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1454 // This is a type that showed up in an 1455 // elaborated-type-specifier inside the anonymous struct or 1456 // union, but which actually declares a type outside of the 1457 // anonymous struct or union. It's okay. 1458 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1459 if (!MemRecord->isAnonymousStructOrUnion() && 1460 MemRecord->getDeclName()) { 1461 // This is a nested type declaration. 1462 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1463 << (int)Record->isUnion(); 1464 Invalid = true; 1465 } 1466 } else { 1467 // We have something that isn't a non-static data 1468 // member. Complain about it. 1469 unsigned DK = diag::err_anonymous_record_bad_member; 1470 if (isa<TypeDecl>(*Mem)) 1471 DK = diag::err_anonymous_record_with_type; 1472 else if (isa<FunctionDecl>(*Mem)) 1473 DK = diag::err_anonymous_record_with_function; 1474 else if (isa<VarDecl>(*Mem)) 1475 DK = diag::err_anonymous_record_with_static; 1476 Diag((*Mem)->getLocation(), DK) 1477 << (int)Record->isUnion(); 1478 Invalid = true; 1479 } 1480 } 1481 } 1482 1483 if (!Record->isUnion() && !Owner->isRecord()) { 1484 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1485 << (int)getLangOptions().CPlusPlus; 1486 Invalid = true; 1487 } 1488 1489 // Create a declaration for this anonymous struct/union. 1490 NamedDecl *Anon = 0; 1491 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1492 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1493 /*IdentifierInfo=*/0, 1494 Context.getTypeDeclType(Record), 1495 // FIXME: Type source info. 1496 /*DInfo=*/0, 1497 /*BitWidth=*/0, /*Mutable=*/false); 1498 Anon->setAccess(AS_public); 1499 if (getLangOptions().CPlusPlus) 1500 FieldCollector->Add(cast<FieldDecl>(Anon)); 1501 } else { 1502 VarDecl::StorageClass SC; 1503 switch (DS.getStorageClassSpec()) { 1504 default: assert(0 && "Unknown storage class!"); 1505 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1506 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1507 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1508 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1509 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1510 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1511 case DeclSpec::SCS_mutable: 1512 // mutable can only appear on non-static class members, so it's always 1513 // an error here 1514 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1515 Invalid = true; 1516 SC = VarDecl::None; 1517 break; 1518 } 1519 1520 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1521 /*IdentifierInfo=*/0, 1522 Context.getTypeDeclType(Record), 1523 // FIXME: Type source info. 1524 /*DInfo=*/0, 1525 SC); 1526 } 1527 Anon->setImplicit(); 1528 1529 // Add the anonymous struct/union object to the current 1530 // context. We'll be referencing this object when we refer to one of 1531 // its members. 1532 Owner->addDecl(Anon); 1533 1534 // Inject the members of the anonymous struct/union into the owning 1535 // context and into the identifier resolver chain for name lookup 1536 // purposes. 1537 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1538 Invalid = true; 1539 1540 // Mark this as an anonymous struct/union type. Note that we do not 1541 // do this until after we have already checked and injected the 1542 // members of this anonymous struct/union type, because otherwise 1543 // the members could be injected twice: once by DeclContext when it 1544 // builds its lookup table, and once by 1545 // InjectAnonymousStructOrUnionMembers. 1546 Record->setAnonymousStructOrUnion(true); 1547 1548 if (Invalid) 1549 Anon->setInvalidDecl(); 1550 1551 return DeclPtrTy::make(Anon); 1552} 1553 1554 1555/// GetNameForDeclarator - Determine the full declaration name for the 1556/// given Declarator. 1557DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1558 switch (D.getKind()) { 1559 case Declarator::DK_Abstract: 1560 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1561 return DeclarationName(); 1562 1563 case Declarator::DK_Normal: 1564 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1565 return DeclarationName(D.getIdentifier()); 1566 1567 case Declarator::DK_Constructor: { 1568 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1569 return Context.DeclarationNames.getCXXConstructorName( 1570 Context.getCanonicalType(Ty)); 1571 } 1572 1573 case Declarator::DK_Destructor: { 1574 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1575 return Context.DeclarationNames.getCXXDestructorName( 1576 Context.getCanonicalType(Ty)); 1577 } 1578 1579 case Declarator::DK_Conversion: { 1580 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1581 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1582 return Context.DeclarationNames.getCXXConversionFunctionName( 1583 Context.getCanonicalType(Ty)); 1584 } 1585 1586 case Declarator::DK_Operator: 1587 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1588 return Context.DeclarationNames.getCXXOperatorName( 1589 D.getOverloadedOperator()); 1590 1591 case Declarator::DK_TemplateId: { 1592 TemplateName Name 1593 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1594 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1595 return Template->getDeclName(); 1596 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1597 return Ovl->getDeclName(); 1598 1599 return DeclarationName(); 1600 } 1601 } 1602 1603 assert(false && "Unknown name kind"); 1604 return DeclarationName(); 1605} 1606 1607/// isNearlyMatchingFunction - Determine whether the C++ functions 1608/// Declaration and Definition are "nearly" matching. This heuristic 1609/// is used to improve diagnostics in the case where an out-of-line 1610/// function definition doesn't match any declaration within 1611/// the class or namespace. 1612static bool isNearlyMatchingFunction(ASTContext &Context, 1613 FunctionDecl *Declaration, 1614 FunctionDecl *Definition) { 1615 if (Declaration->param_size() != Definition->param_size()) 1616 return false; 1617 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1618 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1619 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1620 1621 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1622 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1623 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1624 return false; 1625 } 1626 1627 return true; 1628} 1629 1630Sema::DeclPtrTy 1631Sema::HandleDeclarator(Scope *S, Declarator &D, 1632 MultiTemplateParamsArg TemplateParamLists, 1633 bool IsFunctionDefinition) { 1634 DeclarationName Name = GetNameForDeclarator(D); 1635 1636 // All of these full declarators require an identifier. If it doesn't have 1637 // one, the ParsedFreeStandingDeclSpec action should be used. 1638 if (!Name) { 1639 if (!D.isInvalidType()) // Reject this if we think it is valid. 1640 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1641 diag::err_declarator_need_ident) 1642 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1643 return DeclPtrTy(); 1644 } 1645 1646 // The scope passed in may not be a decl scope. Zip up the scope tree until 1647 // we find one that is. 1648 while ((S->getFlags() & Scope::DeclScope) == 0 || 1649 (S->getFlags() & Scope::TemplateParamScope) != 0) 1650 S = S->getParent(); 1651 1652 // If this is an out-of-line definition of a member of a class template 1653 // or class template partial specialization, we may need to rebuild the 1654 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1655 // for more information. 1656 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1657 // handle expressions properly. 1658 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1659 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1660 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1661 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1662 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1663 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1664 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1665 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1666 // FIXME: Preserve type source info. 1667 QualType T = GetTypeFromParser(DS.getTypeRep()); 1668 EnterDeclaratorContext(S, DC); 1669 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1670 ExitDeclaratorContext(S); 1671 if (T.isNull()) 1672 return DeclPtrTy(); 1673 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1674 } 1675 } 1676 1677 DeclContext *DC; 1678 NamedDecl *PrevDecl; 1679 NamedDecl *New; 1680 1681 DeclaratorInfo *DInfo = 0; 1682 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1683 1684 // See if this is a redefinition of a variable in the same scope. 1685 if (D.getCXXScopeSpec().isInvalid()) { 1686 DC = CurContext; 1687 PrevDecl = 0; 1688 D.setInvalidType(); 1689 } else if (!D.getCXXScopeSpec().isSet()) { 1690 LookupNameKind NameKind = LookupOrdinaryName; 1691 1692 // If the declaration we're planning to build will be a function 1693 // or object with linkage, then look for another declaration with 1694 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1695 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1696 /* Do nothing*/; 1697 else if (R->isFunctionType()) { 1698 if (CurContext->isFunctionOrMethod() || 1699 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1700 NameKind = LookupRedeclarationWithLinkage; 1701 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1702 NameKind = LookupRedeclarationWithLinkage; 1703 else if (CurContext->getLookupContext()->isTranslationUnit() && 1704 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1705 NameKind = LookupRedeclarationWithLinkage; 1706 1707 DC = CurContext; 1708 PrevDecl = LookupName(S, Name, NameKind, true, 1709 NameKind == LookupRedeclarationWithLinkage, 1710 D.getIdentifierLoc()); 1711 } else { // Something like "int foo::x;" 1712 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1713 1714 if (!DC) { 1715 // If we could not compute the declaration context, it's because the 1716 // declaration context is dependent but does not refer to a class, 1717 // class template, or class template partial specialization. Complain 1718 // and return early, to avoid the coming semantic disaster. 1719 Diag(D.getIdentifierLoc(), 1720 diag::err_template_qualified_declarator_no_match) 1721 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1722 << D.getCXXScopeSpec().getRange(); 1723 return DeclPtrTy(); 1724 } 1725 1726 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1727 1728 // C++ 7.3.1.2p2: 1729 // Members (including explicit specializations of templates) of a named 1730 // namespace can also be defined outside that namespace by explicit 1731 // qualification of the name being defined, provided that the entity being 1732 // defined was already declared in the namespace and the definition appears 1733 // after the point of declaration in a namespace that encloses the 1734 // declarations namespace. 1735 // 1736 // Note that we only check the context at this point. We don't yet 1737 // have enough information to make sure that PrevDecl is actually 1738 // the declaration we want to match. For example, given: 1739 // 1740 // class X { 1741 // void f(); 1742 // void f(float); 1743 // }; 1744 // 1745 // void X::f(int) { } // ill-formed 1746 // 1747 // In this case, PrevDecl will point to the overload set 1748 // containing the two f's declared in X, but neither of them 1749 // matches. 1750 1751 // First check whether we named the global scope. 1752 if (isa<TranslationUnitDecl>(DC)) { 1753 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1754 << Name << D.getCXXScopeSpec().getRange(); 1755 } else if (!CurContext->Encloses(DC)) { 1756 // The qualifying scope doesn't enclose the original declaration. 1757 // Emit diagnostic based on current scope. 1758 SourceLocation L = D.getIdentifierLoc(); 1759 SourceRange R = D.getCXXScopeSpec().getRange(); 1760 if (isa<FunctionDecl>(CurContext)) 1761 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1762 else 1763 Diag(L, diag::err_invalid_declarator_scope) 1764 << Name << cast<NamedDecl>(DC) << R; 1765 D.setInvalidType(); 1766 } 1767 } 1768 1769 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1770 // Maybe we will complain about the shadowed template parameter. 1771 if (!D.isInvalidType()) 1772 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1773 D.setInvalidType(); 1774 1775 // Just pretend that we didn't see the previous declaration. 1776 PrevDecl = 0; 1777 } 1778 1779 // In C++, the previous declaration we find might be a tag type 1780 // (class or enum). In this case, the new declaration will hide the 1781 // tag type. Note that this does does not apply if we're declaring a 1782 // typedef (C++ [dcl.typedef]p4). 1783 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1784 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1785 PrevDecl = 0; 1786 1787 bool Redeclaration = false; 1788 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1789 if (TemplateParamLists.size()) { 1790 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1791 return DeclPtrTy(); 1792 } 1793 1794 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1795 } else if (R->isFunctionType()) { 1796 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1797 move(TemplateParamLists), 1798 IsFunctionDefinition, Redeclaration); 1799 } else { 1800 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1801 move(TemplateParamLists), 1802 Redeclaration); 1803 } 1804 1805 if (New == 0) 1806 return DeclPtrTy(); 1807 1808 // If this has an identifier and is not an invalid redeclaration or 1809 // function template specialization, add it to the scope stack. 1810 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1811 !(isa<FunctionDecl>(New) && 1812 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1813 PushOnScopeChains(New, S); 1814 1815 return DeclPtrTy::make(New); 1816} 1817 1818/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1819/// types into constant array types in certain situations which would otherwise 1820/// be errors (for GCC compatibility). 1821static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1822 ASTContext &Context, 1823 bool &SizeIsNegative) { 1824 // This method tries to turn a variable array into a constant 1825 // array even when the size isn't an ICE. This is necessary 1826 // for compatibility with code that depends on gcc's buggy 1827 // constant expression folding, like struct {char x[(int)(char*)2];} 1828 SizeIsNegative = false; 1829 1830 QualifierCollector Qs; 1831 const Type *Ty = Qs.strip(T); 1832 1833 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1834 QualType Pointee = PTy->getPointeeType(); 1835 QualType FixedType = 1836 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1837 if (FixedType.isNull()) return FixedType; 1838 FixedType = Context.getPointerType(FixedType); 1839 return Qs.apply(FixedType); 1840 } 1841 1842 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1843 if (!VLATy) 1844 return QualType(); 1845 // FIXME: We should probably handle this case 1846 if (VLATy->getElementType()->isVariablyModifiedType()) 1847 return QualType(); 1848 1849 Expr::EvalResult EvalResult; 1850 if (!VLATy->getSizeExpr() || 1851 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1852 !EvalResult.Val.isInt()) 1853 return QualType(); 1854 1855 llvm::APSInt &Res = EvalResult.Val.getInt(); 1856 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1857 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1858 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1859 // so as to transfer ownership to the ConstantArrayWithExpr. 1860 // Alternatively, we could "clone" it (how?). 1861 // Since we don't know how to do things above, we just use the 1862 // very same Expr*. 1863 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1864 Res, ArySizeExpr, 1865 ArrayType::Normal, 0, 1866 VLATy->getBracketsRange()); 1867 } 1868 1869 SizeIsNegative = true; 1870 return QualType(); 1871} 1872 1873/// \brief Register the given locally-scoped external C declaration so 1874/// that it can be found later for redeclarations 1875void 1876Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1877 Scope *S) { 1878 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1879 "Decl is not a locally-scoped decl!"); 1880 // Note that we have a locally-scoped external with this name. 1881 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1882 1883 if (!PrevDecl) 1884 return; 1885 1886 // If there was a previous declaration of this variable, it may be 1887 // in our identifier chain. Update the identifier chain with the new 1888 // declaration. 1889 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1890 // The previous declaration was found on the identifer resolver 1891 // chain, so remove it from its scope. 1892 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1893 S = S->getParent(); 1894 1895 if (S) 1896 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1897 } 1898} 1899 1900/// \brief Diagnose function specifiers on a declaration of an identifier that 1901/// does not identify a function. 1902void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1903 // FIXME: We should probably indicate the identifier in question to avoid 1904 // confusion for constructs like "inline int a(), b;" 1905 if (D.getDeclSpec().isInlineSpecified()) 1906 Diag(D.getDeclSpec().getInlineSpecLoc(), 1907 diag::err_inline_non_function); 1908 1909 if (D.getDeclSpec().isVirtualSpecified()) 1910 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1911 diag::err_virtual_non_function); 1912 1913 if (D.getDeclSpec().isExplicitSpecified()) 1914 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1915 diag::err_explicit_non_function); 1916} 1917 1918NamedDecl* 1919Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1920 QualType R, DeclaratorInfo *DInfo, 1921 Decl* PrevDecl, bool &Redeclaration) { 1922 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1923 if (D.getCXXScopeSpec().isSet()) { 1924 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1925 << D.getCXXScopeSpec().getRange(); 1926 D.setInvalidType(); 1927 // Pretend we didn't see the scope specifier. 1928 DC = 0; 1929 } 1930 1931 if (getLangOptions().CPlusPlus) { 1932 // Check that there are no default arguments (C++ only). 1933 CheckExtraCXXDefaultArguments(D); 1934 } 1935 1936 DiagnoseFunctionSpecifiers(D); 1937 1938 if (D.getDeclSpec().isThreadSpecified()) 1939 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1940 1941 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1942 if (!NewTD) return 0; 1943 1944 if (D.isInvalidType()) 1945 NewTD->setInvalidDecl(); 1946 1947 // Handle attributes prior to checking for duplicates in MergeVarDecl 1948 ProcessDeclAttributes(S, NewTD, D); 1949 // Merge the decl with the existing one if appropriate. If the decl is 1950 // in an outer scope, it isn't the same thing. 1951 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1952 Redeclaration = true; 1953 MergeTypeDefDecl(NewTD, PrevDecl); 1954 } 1955 1956 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1957 // then it shall have block scope. 1958 QualType T = NewTD->getUnderlyingType(); 1959 if (T->isVariablyModifiedType()) { 1960 CurFunctionNeedsScopeChecking = true; 1961 1962 if (S->getFnParent() == 0) { 1963 bool SizeIsNegative; 1964 QualType FixedTy = 1965 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1966 if (!FixedTy.isNull()) { 1967 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1968 NewTD->setUnderlyingType(FixedTy); 1969 } else { 1970 if (SizeIsNegative) 1971 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1972 else if (T->isVariableArrayType()) 1973 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1974 else 1975 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1976 NewTD->setInvalidDecl(); 1977 } 1978 } 1979 } 1980 1981 // If this is the C FILE type, notify the AST context. 1982 if (IdentifierInfo *II = NewTD->getIdentifier()) 1983 if (!NewTD->isInvalidDecl() && 1984 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1985 if (II->isStr("FILE")) 1986 Context.setFILEDecl(NewTD); 1987 else if (II->isStr("jmp_buf")) 1988 Context.setjmp_bufDecl(NewTD); 1989 else if (II->isStr("sigjmp_buf")) 1990 Context.setsigjmp_bufDecl(NewTD); 1991 } 1992 1993 return NewTD; 1994} 1995 1996/// \brief Determines whether the given declaration is an out-of-scope 1997/// previous declaration. 1998/// 1999/// This routine should be invoked when name lookup has found a 2000/// previous declaration (PrevDecl) that is not in the scope where a 2001/// new declaration by the same name is being introduced. If the new 2002/// declaration occurs in a local scope, previous declarations with 2003/// linkage may still be considered previous declarations (C99 2004/// 6.2.2p4-5, C++ [basic.link]p6). 2005/// 2006/// \param PrevDecl the previous declaration found by name 2007/// lookup 2008/// 2009/// \param DC the context in which the new declaration is being 2010/// declared. 2011/// 2012/// \returns true if PrevDecl is an out-of-scope previous declaration 2013/// for a new delcaration with the same name. 2014static bool 2015isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2016 ASTContext &Context) { 2017 if (!PrevDecl) 2018 return 0; 2019 2020 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2021 // case we need to check each of the overloaded functions. 2022 if (!PrevDecl->hasLinkage()) 2023 return false; 2024 2025 if (Context.getLangOptions().CPlusPlus) { 2026 // C++ [basic.link]p6: 2027 // If there is a visible declaration of an entity with linkage 2028 // having the same name and type, ignoring entities declared 2029 // outside the innermost enclosing namespace scope, the block 2030 // scope declaration declares that same entity and receives the 2031 // linkage of the previous declaration. 2032 DeclContext *OuterContext = DC->getLookupContext(); 2033 if (!OuterContext->isFunctionOrMethod()) 2034 // This rule only applies to block-scope declarations. 2035 return false; 2036 else { 2037 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2038 if (PrevOuterContext->isRecord()) 2039 // We found a member function: ignore it. 2040 return false; 2041 else { 2042 // Find the innermost enclosing namespace for the new and 2043 // previous declarations. 2044 while (!OuterContext->isFileContext()) 2045 OuterContext = OuterContext->getParent(); 2046 while (!PrevOuterContext->isFileContext()) 2047 PrevOuterContext = PrevOuterContext->getParent(); 2048 2049 // The previous declaration is in a different namespace, so it 2050 // isn't the same function. 2051 if (OuterContext->getPrimaryContext() != 2052 PrevOuterContext->getPrimaryContext()) 2053 return false; 2054 } 2055 } 2056 } 2057 2058 return true; 2059} 2060 2061NamedDecl* 2062Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2063 QualType R, DeclaratorInfo *DInfo, 2064 NamedDecl* PrevDecl, 2065 MultiTemplateParamsArg TemplateParamLists, 2066 bool &Redeclaration) { 2067 DeclarationName Name = GetNameForDeclarator(D); 2068 2069 // Check that there are no default arguments (C++ only). 2070 if (getLangOptions().CPlusPlus) 2071 CheckExtraCXXDefaultArguments(D); 2072 2073 VarDecl *NewVD; 2074 VarDecl::StorageClass SC; 2075 switch (D.getDeclSpec().getStorageClassSpec()) { 2076 default: assert(0 && "Unknown storage class!"); 2077 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2078 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2079 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2080 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2081 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2082 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2083 case DeclSpec::SCS_mutable: 2084 // mutable can only appear on non-static class members, so it's always 2085 // an error here 2086 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2087 D.setInvalidType(); 2088 SC = VarDecl::None; 2089 break; 2090 } 2091 2092 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2093 if (!II) { 2094 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2095 << Name.getAsString(); 2096 return 0; 2097 } 2098 2099 DiagnoseFunctionSpecifiers(D); 2100 2101 if (!DC->isRecord() && S->getFnParent() == 0) { 2102 // C99 6.9p2: The storage-class specifiers auto and register shall not 2103 // appear in the declaration specifiers in an external declaration. 2104 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2105 2106 // If this is a register variable with an asm label specified, then this 2107 // is a GNU extension. 2108 if (SC == VarDecl::Register && D.getAsmLabel()) 2109 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2110 else 2111 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2112 D.setInvalidType(); 2113 } 2114 } 2115 if (DC->isRecord() && !CurContext->isRecord()) { 2116 // This is an out-of-line definition of a static data member. 2117 if (SC == VarDecl::Static) { 2118 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2119 diag::err_static_out_of_line) 2120 << CodeModificationHint::CreateRemoval( 2121 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2122 } else if (SC == VarDecl::None) 2123 SC = VarDecl::Static; 2124 } 2125 if (SC == VarDecl::Static) { 2126 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2127 if (RD->isLocalClass()) 2128 Diag(D.getIdentifierLoc(), 2129 diag::err_static_data_member_not_allowed_in_local_class) 2130 << Name << RD->getDeclName(); 2131 } 2132 } 2133 2134 // Match up the template parameter lists with the scope specifier, then 2135 // determine whether we have a template or a template specialization. 2136 if (TemplateParameterList *TemplateParams 2137 = MatchTemplateParametersToScopeSpecifier( 2138 D.getDeclSpec().getSourceRange().getBegin(), 2139 D.getCXXScopeSpec(), 2140 (TemplateParameterList**)TemplateParamLists.get(), 2141 TemplateParamLists.size())) { 2142 if (TemplateParams->size() > 0) { 2143 // There is no such thing as a variable template. 2144 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2145 << II 2146 << SourceRange(TemplateParams->getTemplateLoc(), 2147 TemplateParams->getRAngleLoc()); 2148 return 0; 2149 } else { 2150 // There is an extraneous 'template<>' for this variable. Complain 2151 // about it, but allow the declaration of the variable. 2152 Diag(TemplateParams->getTemplateLoc(), 2153 diag::err_template_variable_noparams) 2154 << II 2155 << SourceRange(TemplateParams->getTemplateLoc(), 2156 TemplateParams->getRAngleLoc()); 2157 } 2158 } 2159 2160 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2161 II, R, DInfo, SC); 2162 2163 if (D.isInvalidType()) 2164 NewVD->setInvalidDecl(); 2165 2166 if (D.getDeclSpec().isThreadSpecified()) { 2167 if (NewVD->hasLocalStorage()) 2168 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2169 else if (!Context.Target.isTLSSupported()) 2170 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2171 else 2172 NewVD->setThreadSpecified(true); 2173 } 2174 2175 // Set the lexical context. If the declarator has a C++ scope specifier, the 2176 // lexical context will be different from the semantic context. 2177 NewVD->setLexicalDeclContext(CurContext); 2178 2179 // Handle attributes prior to checking for duplicates in MergeVarDecl 2180 ProcessDeclAttributes(S, NewVD, D); 2181 2182 // Handle GNU asm-label extension (encoded as an attribute). 2183 if (Expr *E = (Expr*) D.getAsmLabel()) { 2184 // The parser guarantees this is a string. 2185 StringLiteral *SE = cast<StringLiteral>(E); 2186 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2187 SE->getByteLength()))); 2188 } 2189 2190 // If name lookup finds a previous declaration that is not in the 2191 // same scope as the new declaration, this may still be an 2192 // acceptable redeclaration. 2193 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2194 !(NewVD->hasLinkage() && 2195 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2196 PrevDecl = 0; 2197 2198 // Merge the decl with the existing one if appropriate. 2199 if (PrevDecl) { 2200 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2201 // The user tried to define a non-static data member 2202 // out-of-line (C++ [dcl.meaning]p1). 2203 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2204 << D.getCXXScopeSpec().getRange(); 2205 PrevDecl = 0; 2206 NewVD->setInvalidDecl(); 2207 } 2208 } else if (D.getCXXScopeSpec().isSet()) { 2209 // No previous declaration in the qualifying scope. 2210 NestedNameSpecifier *NNS = 2211 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2212 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2213 D.getCXXScopeSpec().getRange()); 2214 NewVD->setInvalidDecl(); 2215 } 2216 2217 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2218 2219 // attributes declared post-definition are currently ignored 2220 if (PrevDecl) { 2221 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2222 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2223 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2224 Diag(Def->getLocation(), diag::note_previous_definition); 2225 } 2226 } 2227 2228 // If this is a locally-scoped extern C variable, update the map of 2229 // such variables. 2230 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2231 !NewVD->isInvalidDecl()) 2232 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2233 2234 return NewVD; 2235} 2236 2237/// \brief Perform semantic checking on a newly-created variable 2238/// declaration. 2239/// 2240/// This routine performs all of the type-checking required for a 2241/// variable declaration once it has been built. It is used both to 2242/// check variables after they have been parsed and their declarators 2243/// have been translated into a declaration, and to check variables 2244/// that have been instantiated from a template. 2245/// 2246/// Sets NewVD->isInvalidDecl() if an error was encountered. 2247void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2248 bool &Redeclaration) { 2249 // If the decl is already known invalid, don't check it. 2250 if (NewVD->isInvalidDecl()) 2251 return; 2252 2253 QualType T = NewVD->getType(); 2254 2255 if (T->isObjCInterfaceType()) { 2256 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2257 return NewVD->setInvalidDecl(); 2258 } 2259 2260 // The variable can not have an abstract class type. 2261 if (RequireNonAbstractType(NewVD->getLocation(), T, 2262 diag::err_abstract_type_in_decl, 2263 AbstractVariableType)) 2264 return NewVD->setInvalidDecl(); 2265 2266 // Emit an error if an address space was applied to decl with local storage. 2267 // This includes arrays of objects with address space qualifiers, but not 2268 // automatic variables that point to other address spaces. 2269 // ISO/IEC TR 18037 S5.1.2 2270 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2271 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2272 return NewVD->setInvalidDecl(); 2273 } 2274 2275 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2276 && !NewVD->hasAttr<BlocksAttr>()) 2277 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2278 2279 bool isVM = T->isVariablyModifiedType(); 2280 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2281 NewVD->hasAttr<BlocksAttr>()) 2282 CurFunctionNeedsScopeChecking = true; 2283 2284 if ((isVM && NewVD->hasLinkage()) || 2285 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2286 bool SizeIsNegative; 2287 QualType FixedTy = 2288 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2289 2290 if (FixedTy.isNull() && T->isVariableArrayType()) { 2291 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2292 // FIXME: This won't give the correct result for 2293 // int a[10][n]; 2294 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2295 2296 if (NewVD->isFileVarDecl()) 2297 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2298 << SizeRange; 2299 else if (NewVD->getStorageClass() == VarDecl::Static) 2300 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2301 << SizeRange; 2302 else 2303 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2304 << SizeRange; 2305 return NewVD->setInvalidDecl(); 2306 } 2307 2308 if (FixedTy.isNull()) { 2309 if (NewVD->isFileVarDecl()) 2310 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2311 else 2312 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2313 return NewVD->setInvalidDecl(); 2314 } 2315 2316 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2317 NewVD->setType(FixedTy); 2318 } 2319 2320 if (!PrevDecl && NewVD->isExternC()) { 2321 // Since we did not find anything by this name and we're declaring 2322 // an extern "C" variable, look for a non-visible extern "C" 2323 // declaration with the same name. 2324 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2325 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2326 if (Pos != LocallyScopedExternalDecls.end()) 2327 PrevDecl = Pos->second; 2328 } 2329 2330 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2331 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2332 << T; 2333 return NewVD->setInvalidDecl(); 2334 } 2335 2336 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2337 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2338 return NewVD->setInvalidDecl(); 2339 } 2340 2341 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2342 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2343 return NewVD->setInvalidDecl(); 2344 } 2345 2346 if (PrevDecl) { 2347 Redeclaration = true; 2348 MergeVarDecl(NewVD, PrevDecl); 2349 } 2350} 2351 2352static bool isUsingDecl(Decl *D) { 2353 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2354} 2355 2356NamedDecl* 2357Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2358 QualType R, DeclaratorInfo *DInfo, 2359 NamedDecl* PrevDecl, 2360 MultiTemplateParamsArg TemplateParamLists, 2361 bool IsFunctionDefinition, bool &Redeclaration) { 2362 assert(R.getTypePtr()->isFunctionType()); 2363 2364 DeclarationName Name = GetNameForDeclarator(D); 2365 FunctionDecl::StorageClass SC = FunctionDecl::None; 2366 switch (D.getDeclSpec().getStorageClassSpec()) { 2367 default: assert(0 && "Unknown storage class!"); 2368 case DeclSpec::SCS_auto: 2369 case DeclSpec::SCS_register: 2370 case DeclSpec::SCS_mutable: 2371 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2372 diag::err_typecheck_sclass_func); 2373 D.setInvalidType(); 2374 break; 2375 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2376 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2377 case DeclSpec::SCS_static: { 2378 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2379 // C99 6.7.1p5: 2380 // The declaration of an identifier for a function that has 2381 // block scope shall have no explicit storage-class specifier 2382 // other than extern 2383 // See also (C++ [dcl.stc]p4). 2384 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2385 diag::err_static_block_func); 2386 SC = FunctionDecl::None; 2387 } else 2388 SC = FunctionDecl::Static; 2389 break; 2390 } 2391 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2392 } 2393 2394 if (D.getDeclSpec().isThreadSpecified()) 2395 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2396 2397 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2398 bool isInline = D.getDeclSpec().isInlineSpecified(); 2399 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2400 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2401 2402 // Check that the return type is not an abstract class type. 2403 // For record types, this is done by the AbstractClassUsageDiagnoser once 2404 // the class has been completely parsed. 2405 if (!DC->isRecord() && 2406 RequireNonAbstractType(D.getIdentifierLoc(), 2407 R->getAs<FunctionType>()->getResultType(), 2408 diag::err_abstract_type_in_decl, 2409 AbstractReturnType)) 2410 D.setInvalidType(); 2411 2412 // Do not allow returning a objc interface by-value. 2413 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2414 Diag(D.getIdentifierLoc(), 2415 diag::err_object_cannot_be_passed_returned_by_value) << 0 2416 << R->getAs<FunctionType>()->getResultType(); 2417 D.setInvalidType(); 2418 } 2419 2420 bool isVirtualOkay = false; 2421 FunctionDecl *NewFD; 2422 2423 if (isFriend) { 2424 // DC is the namespace in which the function is being declared. 2425 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2426 "friend function being created in a non-namespace context"); 2427 2428 // C++ [class.friend]p5 2429 // A function can be defined in a friend declaration of a 2430 // class . . . . Such a function is implicitly inline. 2431 isInline |= IsFunctionDefinition; 2432 } 2433 2434 if (D.getKind() == Declarator::DK_Constructor) { 2435 // This is a C++ constructor declaration. 2436 assert(DC->isRecord() && 2437 "Constructors can only be declared in a member context"); 2438 2439 R = CheckConstructorDeclarator(D, R, SC); 2440 2441 // Create the new declaration 2442 NewFD = CXXConstructorDecl::Create(Context, 2443 cast<CXXRecordDecl>(DC), 2444 D.getIdentifierLoc(), Name, R, DInfo, 2445 isExplicit, isInline, 2446 /*isImplicitlyDeclared=*/false); 2447 } else if (D.getKind() == Declarator::DK_Destructor) { 2448 // This is a C++ destructor declaration. 2449 if (DC->isRecord()) { 2450 R = CheckDestructorDeclarator(D, SC); 2451 2452 NewFD = CXXDestructorDecl::Create(Context, 2453 cast<CXXRecordDecl>(DC), 2454 D.getIdentifierLoc(), Name, R, 2455 isInline, 2456 /*isImplicitlyDeclared=*/false); 2457 2458 isVirtualOkay = true; 2459 } else { 2460 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2461 2462 // Create a FunctionDecl to satisfy the function definition parsing 2463 // code path. 2464 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2465 Name, R, DInfo, SC, isInline, 2466 /*hasPrototype=*/true); 2467 D.setInvalidType(); 2468 } 2469 } else if (D.getKind() == Declarator::DK_Conversion) { 2470 if (!DC->isRecord()) { 2471 Diag(D.getIdentifierLoc(), 2472 diag::err_conv_function_not_member); 2473 return 0; 2474 } 2475 2476 CheckConversionDeclarator(D, R, SC); 2477 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2478 D.getIdentifierLoc(), Name, R, DInfo, 2479 isInline, isExplicit); 2480 2481 isVirtualOkay = true; 2482 } else if (DC->isRecord()) { 2483 // If the of the function is the same as the name of the record, then this 2484 // must be an invalid constructor that has a return type. 2485 // (The parser checks for a return type and makes the declarator a 2486 // constructor if it has no return type). 2487 // must have an invalid constructor that has a return type 2488 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2489 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2490 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2491 << SourceRange(D.getIdentifierLoc()); 2492 return 0; 2493 } 2494 2495 // This is a C++ method declaration. 2496 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2497 D.getIdentifierLoc(), Name, R, DInfo, 2498 (SC == FunctionDecl::Static), isInline); 2499 2500 isVirtualOkay = (SC != FunctionDecl::Static); 2501 } else { 2502 // Determine whether the function was written with a 2503 // prototype. This true when: 2504 // - we're in C++ (where every function has a prototype), 2505 // - there is a prototype in the declarator, or 2506 // - the type R of the function is some kind of typedef or other reference 2507 // to a type name (which eventually refers to a function type). 2508 bool HasPrototype = 2509 getLangOptions().CPlusPlus || 2510 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2511 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2512 2513 NewFD = FunctionDecl::Create(Context, DC, 2514 D.getIdentifierLoc(), 2515 Name, R, DInfo, SC, isInline, HasPrototype); 2516 } 2517 2518 if (D.isInvalidType()) 2519 NewFD->setInvalidDecl(); 2520 2521 // Set the lexical context. If the declarator has a C++ 2522 // scope specifier, or is the object of a friend declaration, the 2523 // lexical context will be different from the semantic context. 2524 NewFD->setLexicalDeclContext(CurContext); 2525 2526 if (isFriend) 2527 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2528 2529 // Match up the template parameter lists with the scope specifier, then 2530 // determine whether we have a template or a template specialization. 2531 FunctionTemplateDecl *FunctionTemplate = 0; 2532 bool isFunctionTemplateSpecialization = false; 2533 if (TemplateParameterList *TemplateParams 2534 = MatchTemplateParametersToScopeSpecifier( 2535 D.getDeclSpec().getSourceRange().getBegin(), 2536 D.getCXXScopeSpec(), 2537 (TemplateParameterList**)TemplateParamLists.get(), 2538 TemplateParamLists.size())) { 2539 if (TemplateParams->size() > 0) { 2540 // This is a function template 2541 2542 // Check that we can declare a template here. 2543 if (CheckTemplateDeclScope(S, TemplateParams)) 2544 return 0; 2545 2546 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2547 NewFD->getLocation(), 2548 Name, TemplateParams, 2549 NewFD); 2550 FunctionTemplate->setLexicalDeclContext(CurContext); 2551 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2552 } else { 2553 // This is a function template specialization. 2554 isFunctionTemplateSpecialization = true; 2555 } 2556 2557 // FIXME: Free this memory properly. 2558 TemplateParamLists.release(); 2559 } 2560 2561 // C++ [dcl.fct.spec]p5: 2562 // The virtual specifier shall only be used in declarations of 2563 // nonstatic class member functions that appear within a 2564 // member-specification of a class declaration; see 10.3. 2565 // 2566 if (isVirtual && !NewFD->isInvalidDecl()) { 2567 if (!isVirtualOkay) { 2568 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2569 diag::err_virtual_non_function); 2570 } else if (!CurContext->isRecord()) { 2571 // 'virtual' was specified outside of the class. 2572 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2573 << CodeModificationHint::CreateRemoval( 2574 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2575 } else { 2576 // Okay: Add virtual to the method. 2577 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2578 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2579 CurClass->setAggregate(false); 2580 CurClass->setPOD(false); 2581 CurClass->setEmpty(false); 2582 CurClass->setPolymorphic(true); 2583 CurClass->setHasTrivialConstructor(false); 2584 CurClass->setHasTrivialCopyConstructor(false); 2585 CurClass->setHasTrivialCopyAssignment(false); 2586 } 2587 } 2588 2589 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2590 // Look for virtual methods in base classes that this method might override. 2591 2592 BasePaths Paths; 2593 if (LookupInBases(cast<CXXRecordDecl>(DC), 2594 MemberLookupCriteria(NewMD), Paths)) { 2595 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2596 E = Paths.found_decls_end(); I != E; ++I) { 2597 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2598 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2599 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2600 NewMD->addOverriddenMethod(OldMD); 2601 } 2602 } 2603 } 2604 } 2605 2606 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2607 !CurContext->isRecord()) { 2608 // C++ [class.static]p1: 2609 // A data or function member of a class may be declared static 2610 // in a class definition, in which case it is a static member of 2611 // the class. 2612 2613 // Complain about the 'static' specifier if it's on an out-of-line 2614 // member function definition. 2615 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2616 diag::err_static_out_of_line) 2617 << CodeModificationHint::CreateRemoval( 2618 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2619 } 2620 2621 // Handle GNU asm-label extension (encoded as an attribute). 2622 if (Expr *E = (Expr*) D.getAsmLabel()) { 2623 // The parser guarantees this is a string. 2624 StringLiteral *SE = cast<StringLiteral>(E); 2625 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2626 SE->getByteLength()))); 2627 } 2628 2629 // Copy the parameter declarations from the declarator D to the function 2630 // declaration NewFD, if they are available. First scavenge them into Params. 2631 llvm::SmallVector<ParmVarDecl*, 16> Params; 2632 if (D.getNumTypeObjects() > 0) { 2633 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2634 2635 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2636 // function that takes no arguments, not a function that takes a 2637 // single void argument. 2638 // We let through "const void" here because Sema::GetTypeForDeclarator 2639 // already checks for that case. 2640 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2641 FTI.ArgInfo[0].Param && 2642 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2643 // Empty arg list, don't push any params. 2644 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2645 2646 // In C++, the empty parameter-type-list must be spelled "void"; a 2647 // typedef of void is not permitted. 2648 if (getLangOptions().CPlusPlus && 2649 Param->getType().getUnqualifiedType() != Context.VoidTy) 2650 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2651 // FIXME: Leaks decl? 2652 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2653 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2654 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2655 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2656 Param->setDeclContext(NewFD); 2657 Params.push_back(Param); 2658 } 2659 } 2660 2661 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2662 // When we're declaring a function with a typedef, typeof, etc as in the 2663 // following example, we'll need to synthesize (unnamed) 2664 // parameters for use in the declaration. 2665 // 2666 // @code 2667 // typedef void fn(int); 2668 // fn f; 2669 // @endcode 2670 2671 // Synthesize a parameter for each argument type. 2672 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2673 AE = FT->arg_type_end(); AI != AE; ++AI) { 2674 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2675 SourceLocation(), 0, 2676 *AI, /*DInfo=*/0, 2677 VarDecl::None, 0); 2678 Param->setImplicit(); 2679 Params.push_back(Param); 2680 } 2681 } else { 2682 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2683 "Should not need args for typedef of non-prototype fn"); 2684 } 2685 // Finally, we know we have the right number of parameters, install them. 2686 NewFD->setParams(Context, Params.data(), Params.size()); 2687 2688 // If name lookup finds a previous declaration that is not in the 2689 // same scope as the new declaration, this may still be an 2690 // acceptable redeclaration. 2691 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2692 !(NewFD->hasLinkage() && 2693 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2694 PrevDecl = 0; 2695 2696 // If the declarator is a template-id, translate the parser's template 2697 // argument list into our AST format. 2698 bool HasExplicitTemplateArgs = false; 2699 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2700 SourceLocation LAngleLoc, RAngleLoc; 2701 if (D.getKind() == Declarator::DK_TemplateId) { 2702 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2703 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2704 TemplateId->getTemplateArgs(), 2705 TemplateId->getTemplateArgIsType(), 2706 TemplateId->NumArgs); 2707 translateTemplateArguments(TemplateArgsPtr, 2708 TemplateId->getTemplateArgLocations(), 2709 TemplateArgs); 2710 TemplateArgsPtr.release(); 2711 2712 HasExplicitTemplateArgs = true; 2713 LAngleLoc = TemplateId->LAngleLoc; 2714 RAngleLoc = TemplateId->RAngleLoc; 2715 2716 if (FunctionTemplate) { 2717 // FIXME: Diagnostic function template with explicit template 2718 // arguments. 2719 HasExplicitTemplateArgs = false; 2720 } else if (!isFunctionTemplateSpecialization && 2721 !D.getDeclSpec().isFriendSpecified()) { 2722 // We have encountered something that the user meant to be a 2723 // specialization (because it has explicitly-specified template 2724 // arguments) but that was not introduced with a "template<>" (or had 2725 // too few of them). 2726 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2727 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2728 << CodeModificationHint::CreateInsertion( 2729 D.getDeclSpec().getSourceRange().getBegin(), 2730 "template<> "); 2731 isFunctionTemplateSpecialization = true; 2732 } 2733 } 2734 2735 if (isFunctionTemplateSpecialization && 2736 CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2737 LAngleLoc, TemplateArgs.data(), 2738 TemplateArgs.size(), RAngleLoc, 2739 PrevDecl)) 2740 NewFD->setInvalidDecl(); 2741 2742 // Perform semantic checking on the function declaration. 2743 bool OverloadableAttrRequired = false; // FIXME: HACK! 2744 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2745 /*FIXME:*/OverloadableAttrRequired); 2746 2747 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2748 // An out-of-line member function declaration must also be a 2749 // definition (C++ [dcl.meaning]p1). 2750 // FIXME: Find a better way to recognize out-of-line specializations! 2751 if (!IsFunctionDefinition && !isFriend && 2752 !(TemplateParamLists.size() && !FunctionTemplate)) { 2753 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2754 << D.getCXXScopeSpec().getRange(); 2755 NewFD->setInvalidDecl(); 2756 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2757 // The user tried to provide an out-of-line definition for a 2758 // function that is a member of a class or namespace, but there 2759 // was no such member function declared (C++ [class.mfct]p2, 2760 // C++ [namespace.memdef]p2). For example: 2761 // 2762 // class X { 2763 // void f() const; 2764 // }; 2765 // 2766 // void X::f() { } // ill-formed 2767 // 2768 // Complain about this problem, and attempt to suggest close 2769 // matches (e.g., those that differ only in cv-qualifiers and 2770 // whether the parameter types are references). 2771 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2772 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2773 NewFD->setInvalidDecl(); 2774 2775 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2776 true); 2777 assert(!Prev.isAmbiguous() && 2778 "Cannot have an ambiguity in previous-declaration lookup"); 2779 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2780 Func != FuncEnd; ++Func) { 2781 if (isa<FunctionDecl>(*Func) && 2782 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2783 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2784 } 2785 2786 PrevDecl = 0; 2787 } 2788 } 2789 2790 // Handle attributes. We need to have merged decls when handling attributes 2791 // (for example to check for conflicts, etc). 2792 // FIXME: This needs to happen before we merge declarations. Then, 2793 // let attribute merging cope with attribute conflicts. 2794 ProcessDeclAttributes(S, NewFD, D); 2795 2796 // attributes declared post-definition are currently ignored 2797 if (Redeclaration && PrevDecl) { 2798 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2799 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2800 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2801 Diag(Def->getLocation(), diag::note_previous_definition); 2802 } 2803 } 2804 2805 AddKnownFunctionAttributes(NewFD); 2806 2807 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2808 // If a function name is overloadable in C, then every function 2809 // with that name must be marked "overloadable". 2810 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2811 << Redeclaration << NewFD; 2812 if (PrevDecl) 2813 Diag(PrevDecl->getLocation(), 2814 diag::note_attribute_overloadable_prev_overload); 2815 NewFD->addAttr(::new (Context) OverloadableAttr()); 2816 } 2817 2818 // If this is a locally-scoped extern C function, update the 2819 // map of such names. 2820 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2821 && !NewFD->isInvalidDecl()) 2822 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2823 2824 // Set this FunctionDecl's range up to the right paren. 2825 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2826 2827 if (FunctionTemplate && NewFD->isInvalidDecl()) 2828 FunctionTemplate->setInvalidDecl(); 2829 2830 if (FunctionTemplate) 2831 return FunctionTemplate; 2832 2833 return NewFD; 2834} 2835 2836/// \brief Perform semantic checking of a new function declaration. 2837/// 2838/// Performs semantic analysis of the new function declaration 2839/// NewFD. This routine performs all semantic checking that does not 2840/// require the actual declarator involved in the declaration, and is 2841/// used both for the declaration of functions as they are parsed 2842/// (called via ActOnDeclarator) and for the declaration of functions 2843/// that have been instantiated via C++ template instantiation (called 2844/// via InstantiateDecl). 2845/// 2846/// This sets NewFD->isInvalidDecl() to true if there was an error. 2847void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2848 bool &Redeclaration, 2849 bool &OverloadableAttrRequired) { 2850 // If NewFD is already known erroneous, don't do any of this checking. 2851 if (NewFD->isInvalidDecl()) 2852 return; 2853 2854 if (NewFD->getResultType()->isVariablyModifiedType()) { 2855 // Functions returning a variably modified type violate C99 6.7.5.2p2 2856 // because all functions have linkage. 2857 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2858 return NewFD->setInvalidDecl(); 2859 } 2860 2861 if (NewFD->isMain()) 2862 CheckMain(NewFD); 2863 2864 // Check for a previous declaration of this name. 2865 if (!PrevDecl && NewFD->isExternC()) { 2866 // Since we did not find anything by this name and we're declaring 2867 // an extern "C" function, look for a non-visible extern "C" 2868 // declaration with the same name. 2869 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2870 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2871 if (Pos != LocallyScopedExternalDecls.end()) 2872 PrevDecl = Pos->second; 2873 } 2874 2875 // Merge or overload the declaration with an existing declaration of 2876 // the same name, if appropriate. 2877 if (PrevDecl) { 2878 // Determine whether NewFD is an overload of PrevDecl or 2879 // a declaration that requires merging. If it's an overload, 2880 // there's no more work to do here; we'll just add the new 2881 // function to the scope. 2882 OverloadedFunctionDecl::function_iterator MatchedDecl; 2883 2884 if (!getLangOptions().CPlusPlus && 2885 AllowOverloadingOfFunction(PrevDecl, Context)) { 2886 OverloadableAttrRequired = true; 2887 2888 // Functions marked "overloadable" must have a prototype (that 2889 // we can't get through declaration merging). 2890 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2891 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2892 << NewFD; 2893 Redeclaration = true; 2894 2895 // Turn this into a variadic function with no parameters. 2896 QualType R = Context.getFunctionType( 2897 NewFD->getType()->getAs<FunctionType>()->getResultType(), 2898 0, 0, true, 0); 2899 NewFD->setType(R); 2900 return NewFD->setInvalidDecl(); 2901 } 2902 } 2903 2904 if (PrevDecl && 2905 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2906 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2907 Redeclaration = true; 2908 Decl *OldDecl = PrevDecl; 2909 2910 // If PrevDecl was an overloaded function, extract the 2911 // FunctionDecl that matched. 2912 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2913 OldDecl = *MatchedDecl; 2914 2915 // NewFD and OldDecl represent declarations that need to be 2916 // merged. 2917 if (MergeFunctionDecl(NewFD, OldDecl)) 2918 return NewFD->setInvalidDecl(); 2919 2920 if (FunctionTemplateDecl *OldTemplateDecl 2921 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2922 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2923 else { 2924 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2925 NewFD->setAccess(OldDecl->getAccess()); 2926 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2927 } 2928 } 2929 } 2930 2931 // Semantic checking for this function declaration (in isolation). 2932 if (getLangOptions().CPlusPlus) { 2933 // C++-specific checks. 2934 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2935 CheckConstructor(Constructor); 2936 } else if (isa<CXXDestructorDecl>(NewFD)) { 2937 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2938 QualType ClassType = Context.getTypeDeclType(Record); 2939 if (!ClassType->isDependentType()) { 2940 DeclarationName Name 2941 = Context.DeclarationNames.getCXXDestructorName( 2942 Context.getCanonicalType(ClassType)); 2943 if (NewFD->getDeclName() != Name) { 2944 Diag(NewFD->getLocation(), diag::err_destructor_name); 2945 return NewFD->setInvalidDecl(); 2946 } 2947 } 2948 Record->setUserDeclaredDestructor(true); 2949 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2950 // user-defined destructor. 2951 Record->setPOD(false); 2952 2953 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2954 // declared destructor. 2955 // FIXME: C++0x: don't do this for "= default" destructors 2956 Record->setHasTrivialDestructor(false); 2957 } else if (CXXConversionDecl *Conversion 2958 = dyn_cast<CXXConversionDecl>(NewFD)) 2959 ActOnConversionDeclarator(Conversion); 2960 2961 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2962 if (NewFD->isOverloadedOperator() && 2963 CheckOverloadedOperatorDeclaration(NewFD)) 2964 return NewFD->setInvalidDecl(); 2965 2966 // In C++, check default arguments now that we have merged decls. Unless 2967 // the lexical context is the class, because in this case this is done 2968 // during delayed parsing anyway. 2969 if (!CurContext->isRecord()) 2970 CheckCXXDefaultArguments(NewFD); 2971 } 2972} 2973 2974void Sema::CheckMain(FunctionDecl* FD) { 2975 // C++ [basic.start.main]p3: A program that declares main to be inline 2976 // or static is ill-formed. 2977 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2978 // shall not appear in a declaration of main. 2979 // static main is not an error under C99, but we should warn about it. 2980 bool isInline = FD->isInline(); 2981 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2982 if (isInline || isStatic) { 2983 unsigned diagID = diag::warn_unusual_main_decl; 2984 if (isInline || getLangOptions().CPlusPlus) 2985 diagID = diag::err_unusual_main_decl; 2986 2987 int which = isStatic + (isInline << 1) - 1; 2988 Diag(FD->getLocation(), diagID) << which; 2989 } 2990 2991 QualType T = FD->getType(); 2992 assert(T->isFunctionType() && "function decl is not of function type"); 2993 const FunctionType* FT = T->getAs<FunctionType>(); 2994 2995 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2996 // TODO: add a replacement fixit to turn the return type into 'int'. 2997 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2998 FD->setInvalidDecl(true); 2999 } 3000 3001 // Treat protoless main() as nullary. 3002 if (isa<FunctionNoProtoType>(FT)) return; 3003 3004 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3005 unsigned nparams = FTP->getNumArgs(); 3006 assert(FD->getNumParams() == nparams); 3007 3008 if (nparams > 3) { 3009 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3010 FD->setInvalidDecl(true); 3011 nparams = 3; 3012 } 3013 3014 // FIXME: a lot of the following diagnostics would be improved 3015 // if we had some location information about types. 3016 3017 QualType CharPP = 3018 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3019 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3020 3021 for (unsigned i = 0; i < nparams; ++i) { 3022 QualType AT = FTP->getArgType(i); 3023 3024 bool mismatch = true; 3025 3026 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3027 mismatch = false; 3028 else if (Expected[i] == CharPP) { 3029 // As an extension, the following forms are okay: 3030 // char const ** 3031 // char const * const * 3032 // char * const * 3033 3034 QualifierCollector qs; 3035 const PointerType* PT; 3036 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3037 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3038 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3039 qs.removeConst(); 3040 mismatch = !qs.empty(); 3041 } 3042 } 3043 3044 if (mismatch) { 3045 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3046 // TODO: suggest replacing given type with expected type 3047 FD->setInvalidDecl(true); 3048 } 3049 } 3050 3051 if (nparams == 1 && !FD->isInvalidDecl()) { 3052 Diag(FD->getLocation(), diag::warn_main_one_arg); 3053 } 3054} 3055 3056bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3057 // FIXME: Need strict checking. In C89, we need to check for 3058 // any assignment, increment, decrement, function-calls, or 3059 // commas outside of a sizeof. In C99, it's the same list, 3060 // except that the aforementioned are allowed in unevaluated 3061 // expressions. Everything else falls under the 3062 // "may accept other forms of constant expressions" exception. 3063 // (We never end up here for C++, so the constant expression 3064 // rules there don't matter.) 3065 if (Init->isConstantInitializer(Context)) 3066 return false; 3067 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3068 << Init->getSourceRange(); 3069 return true; 3070} 3071 3072void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3073 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3074} 3075 3076/// AddInitializerToDecl - Adds the initializer Init to the 3077/// declaration dcl. If DirectInit is true, this is C++ direct 3078/// initialization rather than copy initialization. 3079void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3080 Decl *RealDecl = dcl.getAs<Decl>(); 3081 // If there is no declaration, there was an error parsing it. Just ignore 3082 // the initializer. 3083 if (RealDecl == 0) 3084 return; 3085 3086 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3087 // With declarators parsed the way they are, the parser cannot 3088 // distinguish between a normal initializer and a pure-specifier. 3089 // Thus this grotesque test. 3090 IntegerLiteral *IL; 3091 Expr *Init = static_cast<Expr *>(init.get()); 3092 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3093 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3094 if (Method->isVirtualAsWritten()) { 3095 Method->setPure(); 3096 3097 // A class is abstract if at least one function is pure virtual. 3098 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3099 } else if (!Method->isInvalidDecl()) { 3100 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3101 << Method->getDeclName() << Init->getSourceRange(); 3102 Method->setInvalidDecl(); 3103 } 3104 } else { 3105 Diag(Method->getLocation(), diag::err_member_function_initialization) 3106 << Method->getDeclName() << Init->getSourceRange(); 3107 Method->setInvalidDecl(); 3108 } 3109 return; 3110 } 3111 3112 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3113 if (!VDecl) { 3114 if (getLangOptions().CPlusPlus && 3115 RealDecl->getLexicalDeclContext()->isRecord() && 3116 isa<NamedDecl>(RealDecl)) 3117 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3118 << cast<NamedDecl>(RealDecl)->getDeclName(); 3119 else 3120 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3121 RealDecl->setInvalidDecl(); 3122 return; 3123 } 3124 3125 if (!VDecl->getType()->isArrayType() && 3126 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3127 diag::err_typecheck_decl_incomplete_type)) { 3128 RealDecl->setInvalidDecl(); 3129 return; 3130 } 3131 3132 const VarDecl *Def = 0; 3133 if (VDecl->getDefinition(Def)) { 3134 Diag(VDecl->getLocation(), diag::err_redefinition) 3135 << VDecl->getDeclName(); 3136 Diag(Def->getLocation(), diag::note_previous_definition); 3137 VDecl->setInvalidDecl(); 3138 return; 3139 } 3140 3141 // Take ownership of the expression, now that we're sure we have somewhere 3142 // to put it. 3143 Expr *Init = init.takeAs<Expr>(); 3144 assert(Init && "missing initializer"); 3145 3146 // Get the decls type and save a reference for later, since 3147 // CheckInitializerTypes may change it. 3148 QualType DclT = VDecl->getType(), SavT = DclT; 3149 if (VDecl->isBlockVarDecl()) { 3150 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3151 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3152 VDecl->setInvalidDecl(); 3153 } else if (!VDecl->isInvalidDecl()) { 3154 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3155 VDecl->getDeclName(), DirectInit)) 3156 VDecl->setInvalidDecl(); 3157 3158 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3159 // Don't check invalid declarations to avoid emitting useless diagnostics. 3160 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3161 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3162 CheckForConstantInitializer(Init, DclT); 3163 } 3164 } 3165 } else if (VDecl->isStaticDataMember() && 3166 VDecl->getLexicalDeclContext()->isRecord()) { 3167 // This is an in-class initialization for a static data member, e.g., 3168 // 3169 // struct S { 3170 // static const int value = 17; 3171 // }; 3172 3173 // Attach the initializer 3174 VDecl->setInit(Context, Init); 3175 3176 // C++ [class.mem]p4: 3177 // A member-declarator can contain a constant-initializer only 3178 // if it declares a static member (9.4) of const integral or 3179 // const enumeration type, see 9.4.2. 3180 QualType T = VDecl->getType(); 3181 if (!T->isDependentType() && 3182 (!Context.getCanonicalType(T).isConstQualified() || 3183 !T->isIntegralType())) { 3184 Diag(VDecl->getLocation(), diag::err_member_initialization) 3185 << VDecl->getDeclName() << Init->getSourceRange(); 3186 VDecl->setInvalidDecl(); 3187 } else { 3188 // C++ [class.static.data]p4: 3189 // If a static data member is of const integral or const 3190 // enumeration type, its declaration in the class definition 3191 // can specify a constant-initializer which shall be an 3192 // integral constant expression (5.19). 3193 if (!Init->isTypeDependent() && 3194 !Init->getType()->isIntegralType()) { 3195 // We have a non-dependent, non-integral or enumeration type. 3196 Diag(Init->getSourceRange().getBegin(), 3197 diag::err_in_class_initializer_non_integral_type) 3198 << Init->getType() << Init->getSourceRange(); 3199 VDecl->setInvalidDecl(); 3200 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3201 // Check whether the expression is a constant expression. 3202 llvm::APSInt Value; 3203 SourceLocation Loc; 3204 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3205 Diag(Loc, diag::err_in_class_initializer_non_constant) 3206 << Init->getSourceRange(); 3207 VDecl->setInvalidDecl(); 3208 } else if (!VDecl->getType()->isDependentType()) 3209 ImpCastExprToType(Init, VDecl->getType()); 3210 } 3211 } 3212 } else if (VDecl->isFileVarDecl()) { 3213 if (VDecl->getStorageClass() == VarDecl::Extern) 3214 Diag(VDecl->getLocation(), diag::warn_extern_init); 3215 if (!VDecl->isInvalidDecl()) 3216 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3217 VDecl->getDeclName(), DirectInit)) 3218 VDecl->setInvalidDecl(); 3219 3220 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3221 // Don't check invalid declarations to avoid emitting useless diagnostics. 3222 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3223 // C99 6.7.8p4. All file scoped initializers need to be constant. 3224 CheckForConstantInitializer(Init, DclT); 3225 } 3226 } 3227 // If the type changed, it means we had an incomplete type that was 3228 // completed by the initializer. For example: 3229 // int ary[] = { 1, 3, 5 }; 3230 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3231 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3232 VDecl->setType(DclT); 3233 Init->setType(DclT); 3234 } 3235 3236 Init = MaybeCreateCXXExprWithTemporaries(Init, 3237 /*ShouldDestroyTemporaries=*/true); 3238 // Attach the initializer to the decl. 3239 VDecl->setInit(Context, Init); 3240 3241 // If the previous declaration of VDecl was a tentative definition, 3242 // remove it from the set of tentative definitions. 3243 if (VDecl->getPreviousDeclaration() && 3244 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3245 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3246 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3247 } 3248 3249 return; 3250} 3251 3252void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3253 bool TypeContainsUndeducedAuto) { 3254 Decl *RealDecl = dcl.getAs<Decl>(); 3255 3256 // If there is no declaration, there was an error parsing it. Just ignore it. 3257 if (RealDecl == 0) 3258 return; 3259 3260 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3261 QualType Type = Var->getType(); 3262 3263 // Record tentative definitions. 3264 if (Var->isTentativeDefinition(Context)) { 3265 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3266 InsertPair = 3267 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3268 3269 // Keep the latest definition in the map. If we see 'int i; int i;' we 3270 // want the second one in the map. 3271 InsertPair.first->second = Var; 3272 3273 // However, for the list, we don't care about the order, just make sure 3274 // that there are no dupes for a given declaration name. 3275 if (InsertPair.second) 3276 TentativeDefinitionList.push_back(Var->getDeclName()); 3277 } 3278 3279 // C++ [dcl.init.ref]p3: 3280 // The initializer can be omitted for a reference only in a 3281 // parameter declaration (8.3.5), in the declaration of a 3282 // function return type, in the declaration of a class member 3283 // within its class declaration (9.2), and where the extern 3284 // specifier is explicitly used. 3285 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3286 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3287 << Var->getDeclName() 3288 << SourceRange(Var->getLocation(), Var->getLocation()); 3289 Var->setInvalidDecl(); 3290 return; 3291 } 3292 3293 // C++0x [dcl.spec.auto]p3 3294 if (TypeContainsUndeducedAuto) { 3295 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3296 << Var->getDeclName() << Type; 3297 Var->setInvalidDecl(); 3298 return; 3299 } 3300 3301 // C++ [dcl.init]p9: 3302 // If no initializer is specified for an object, and the object 3303 // is of (possibly cv-qualified) non-POD class type (or array 3304 // thereof), the object shall be default-initialized; if the 3305 // object is of const-qualified type, the underlying class type 3306 // shall have a user-declared default constructor. 3307 // 3308 // FIXME: Diagnose the "user-declared default constructor" bit. 3309 if (getLangOptions().CPlusPlus) { 3310 QualType InitType = Type; 3311 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3312 InitType = Array->getElementType(); 3313 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3314 InitType->isRecordType() && !InitType->isDependentType()) { 3315 if (!RequireCompleteType(Var->getLocation(), InitType, 3316 diag::err_invalid_incomplete_type_use)) { 3317 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3318 3319 CXXConstructorDecl *Constructor 3320 = PerformInitializationByConstructor(InitType, 3321 MultiExprArg(*this, 0, 0), 3322 Var->getLocation(), 3323 SourceRange(Var->getLocation(), 3324 Var->getLocation()), 3325 Var->getDeclName(), 3326 IK_Default, 3327 ConstructorArgs); 3328 3329 // FIXME: Location info for the variable initialization? 3330 if (!Constructor) 3331 Var->setInvalidDecl(); 3332 else { 3333 // FIXME: Cope with initialization of arrays 3334 if (!Constructor->isTrivial() && 3335 InitializeVarWithConstructor(Var, Constructor, InitType, 3336 move_arg(ConstructorArgs))) 3337 Var->setInvalidDecl(); 3338 3339 FinalizeVarWithDestructor(Var, InitType); 3340 } 3341 } 3342 } 3343 } 3344 3345#if 0 3346 // FIXME: Temporarily disabled because we are not properly parsing 3347 // linkage specifications on declarations, e.g., 3348 // 3349 // extern "C" const CGPoint CGPointerZero; 3350 // 3351 // C++ [dcl.init]p9: 3352 // 3353 // If no initializer is specified for an object, and the 3354 // object is of (possibly cv-qualified) non-POD class type (or 3355 // array thereof), the object shall be default-initialized; if 3356 // the object is of const-qualified type, the underlying class 3357 // type shall have a user-declared default 3358 // constructor. Otherwise, if no initializer is specified for 3359 // an object, the object and its subobjects, if any, have an 3360 // indeterminate initial value; if the object or any of its 3361 // subobjects are of const-qualified type, the program is 3362 // ill-formed. 3363 // 3364 // This isn't technically an error in C, so we don't diagnose it. 3365 // 3366 // FIXME: Actually perform the POD/user-defined default 3367 // constructor check. 3368 if (getLangOptions().CPlusPlus && 3369 Context.getCanonicalType(Type).isConstQualified() && 3370 !Var->hasExternalStorage()) 3371 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3372 << Var->getName() 3373 << SourceRange(Var->getLocation(), Var->getLocation()); 3374#endif 3375 } 3376} 3377 3378Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3379 DeclPtrTy *Group, 3380 unsigned NumDecls) { 3381 llvm::SmallVector<Decl*, 8> Decls; 3382 3383 if (DS.isTypeSpecOwned()) 3384 Decls.push_back((Decl*)DS.getTypeRep()); 3385 3386 for (unsigned i = 0; i != NumDecls; ++i) 3387 if (Decl *D = Group[i].getAs<Decl>()) 3388 Decls.push_back(D); 3389 3390 // Perform semantic analysis that depends on having fully processed both 3391 // the declarator and initializer. 3392 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3393 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3394 if (!IDecl) 3395 continue; 3396 QualType T = IDecl->getType(); 3397 3398 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3399 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3400 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3401 if (!IDecl->isInvalidDecl() && 3402 RequireCompleteType(IDecl->getLocation(), T, 3403 diag::err_typecheck_decl_incomplete_type)) 3404 IDecl->setInvalidDecl(); 3405 } 3406 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3407 // object that has file scope without an initializer, and without a 3408 // storage-class specifier or with the storage-class specifier "static", 3409 // constitutes a tentative definition. Note: A tentative definition with 3410 // external linkage is valid (C99 6.2.2p5). 3411 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3412 if (const IncompleteArrayType *ArrayT 3413 = Context.getAsIncompleteArrayType(T)) { 3414 if (RequireCompleteType(IDecl->getLocation(), 3415 ArrayT->getElementType(), 3416 diag::err_illegal_decl_array_incomplete_type)) 3417 IDecl->setInvalidDecl(); 3418 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3419 // C99 6.9.2p3: If the declaration of an identifier for an object is 3420 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3421 // declared type shall not be an incomplete type. 3422 // NOTE: code such as the following 3423 // static struct s; 3424 // struct s { int a; }; 3425 // is accepted by gcc. Hence here we issue a warning instead of 3426 // an error and we do not invalidate the static declaration. 3427 // NOTE: to avoid multiple warnings, only check the first declaration. 3428 if (IDecl->getPreviousDeclaration() == 0) 3429 RequireCompleteType(IDecl->getLocation(), T, 3430 diag::ext_typecheck_decl_incomplete_type); 3431 } 3432 } 3433 } 3434 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3435 Decls.data(), Decls.size())); 3436} 3437 3438 3439/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3440/// to introduce parameters into function prototype scope. 3441Sema::DeclPtrTy 3442Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3443 const DeclSpec &DS = D.getDeclSpec(); 3444 3445 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3446 VarDecl::StorageClass StorageClass = VarDecl::None; 3447 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3448 StorageClass = VarDecl::Register; 3449 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3450 Diag(DS.getStorageClassSpecLoc(), 3451 diag::err_invalid_storage_class_in_func_decl); 3452 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3453 } 3454 3455 if (D.getDeclSpec().isThreadSpecified()) 3456 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3457 3458 DiagnoseFunctionSpecifiers(D); 3459 3460 // Check that there are no default arguments inside the type of this 3461 // parameter (C++ only). 3462 if (getLangOptions().CPlusPlus) 3463 CheckExtraCXXDefaultArguments(D); 3464 3465 DeclaratorInfo *DInfo = 0; 3466 TagDecl *OwnedDecl = 0; 3467 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3468 &OwnedDecl); 3469 3470 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3471 // C++ [dcl.fct]p6: 3472 // Types shall not be defined in return or parameter types. 3473 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3474 << Context.getTypeDeclType(OwnedDecl); 3475 } 3476 3477 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3478 // Can this happen for params? We already checked that they don't conflict 3479 // among each other. Here they can only shadow globals, which is ok. 3480 IdentifierInfo *II = D.getIdentifier(); 3481 if (II) { 3482 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3483 if (PrevDecl->isTemplateParameter()) { 3484 // Maybe we will complain about the shadowed template parameter. 3485 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3486 // Just pretend that we didn't see the previous declaration. 3487 PrevDecl = 0; 3488 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3489 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3490 3491 // Recover by removing the name 3492 II = 0; 3493 D.SetIdentifier(0, D.getIdentifierLoc()); 3494 } 3495 } 3496 } 3497 3498 // Parameters can not be abstract class types. 3499 // For record types, this is done by the AbstractClassUsageDiagnoser once 3500 // the class has been completely parsed. 3501 if (!CurContext->isRecord() && 3502 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3503 diag::err_abstract_type_in_decl, 3504 AbstractParamType)) 3505 D.setInvalidType(true); 3506 3507 QualType T = adjustParameterType(parmDeclType); 3508 3509 ParmVarDecl *New; 3510 if (T == parmDeclType) // parameter type did not need adjustment 3511 New = ParmVarDecl::Create(Context, CurContext, 3512 D.getIdentifierLoc(), II, 3513 parmDeclType, DInfo, StorageClass, 3514 0); 3515 else // keep track of both the adjusted and unadjusted types 3516 New = OriginalParmVarDecl::Create(Context, CurContext, 3517 D.getIdentifierLoc(), II, T, DInfo, 3518 parmDeclType, StorageClass, 0); 3519 3520 if (D.isInvalidType()) 3521 New->setInvalidDecl(); 3522 3523 // Parameter declarators cannot be interface types. All ObjC objects are 3524 // passed by reference. 3525 if (T->isObjCInterfaceType()) { 3526 Diag(D.getIdentifierLoc(), 3527 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3528 New->setInvalidDecl(); 3529 } 3530 3531 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3532 if (D.getCXXScopeSpec().isSet()) { 3533 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3534 << D.getCXXScopeSpec().getRange(); 3535 New->setInvalidDecl(); 3536 } 3537 3538 // Add the parameter declaration into this scope. 3539 S->AddDecl(DeclPtrTy::make(New)); 3540 if (II) 3541 IdResolver.AddDecl(New); 3542 3543 ProcessDeclAttributes(S, New, D); 3544 3545 if (New->hasAttr<BlocksAttr>()) { 3546 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3547 } 3548 return DeclPtrTy::make(New); 3549} 3550 3551void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3552 SourceLocation LocAfterDecls) { 3553 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3554 "Not a function declarator!"); 3555 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3556 3557 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3558 // for a K&R function. 3559 if (!FTI.hasPrototype) { 3560 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3561 --i; 3562 if (FTI.ArgInfo[i].Param == 0) { 3563 std::string Code = " int "; 3564 Code += FTI.ArgInfo[i].Ident->getName(); 3565 Code += ";\n"; 3566 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3567 << FTI.ArgInfo[i].Ident 3568 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3569 3570 // Implicitly declare the argument as type 'int' for lack of a better 3571 // type. 3572 DeclSpec DS; 3573 const char* PrevSpec; // unused 3574 unsigned DiagID; // unused 3575 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3576 PrevSpec, DiagID); 3577 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3578 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3579 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3580 } 3581 } 3582 } 3583} 3584 3585Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3586 Declarator &D) { 3587 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3588 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3589 "Not a function declarator!"); 3590 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3591 3592 if (FTI.hasPrototype) { 3593 // FIXME: Diagnose arguments without names in C. 3594 } 3595 3596 Scope *ParentScope = FnBodyScope->getParent(); 3597 3598 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3599 MultiTemplateParamsArg(*this), 3600 /*IsFunctionDefinition=*/true); 3601 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3602} 3603 3604Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3605 if (!D) 3606 return D; 3607 FunctionDecl *FD = 0; 3608 3609 if (FunctionTemplateDecl *FunTmpl 3610 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3611 FD = FunTmpl->getTemplatedDecl(); 3612 else 3613 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3614 3615 CurFunctionNeedsScopeChecking = false; 3616 3617 // See if this is a redefinition. 3618 const FunctionDecl *Definition; 3619 if (FD->getBody(Definition)) { 3620 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3621 Diag(Definition->getLocation(), diag::note_previous_definition); 3622 } 3623 3624 // Builtin functions cannot be defined. 3625 if (unsigned BuiltinID = FD->getBuiltinID()) { 3626 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3627 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3628 FD->setInvalidDecl(); 3629 } 3630 } 3631 3632 // The return type of a function definition must be complete 3633 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3634 QualType ResultType = FD->getResultType(); 3635 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3636 !FD->isInvalidDecl() && 3637 RequireCompleteType(FD->getLocation(), ResultType, 3638 diag::err_func_def_incomplete_result)) 3639 FD->setInvalidDecl(); 3640 3641 // GNU warning -Wmissing-prototypes: 3642 // Warn if a global function is defined without a previous 3643 // prototype declaration. This warning is issued even if the 3644 // definition itself provides a prototype. The aim is to detect 3645 // global functions that fail to be declared in header files. 3646 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3647 !FD->isMain()) { 3648 bool MissingPrototype = true; 3649 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3650 Prev; Prev = Prev->getPreviousDeclaration()) { 3651 // Ignore any declarations that occur in function or method 3652 // scope, because they aren't visible from the header. 3653 if (Prev->getDeclContext()->isFunctionOrMethod()) 3654 continue; 3655 3656 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3657 break; 3658 } 3659 3660 if (MissingPrototype) 3661 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3662 } 3663 3664 if (FnBodyScope) 3665 PushDeclContext(FnBodyScope, FD); 3666 3667 // Check the validity of our function parameters 3668 CheckParmsForFunctionDef(FD); 3669 3670 // Introduce our parameters into the function scope 3671 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3672 ParmVarDecl *Param = FD->getParamDecl(p); 3673 Param->setOwningFunction(FD); 3674 3675 // If this has an identifier, add it to the scope stack. 3676 if (Param->getIdentifier() && FnBodyScope) 3677 PushOnScopeChains(Param, FnBodyScope); 3678 } 3679 3680 // Checking attributes of current function definition 3681 // dllimport attribute. 3682 if (FD->getAttr<DLLImportAttr>() && 3683 (!FD->getAttr<DLLExportAttr>())) { 3684 // dllimport attribute cannot be applied to definition. 3685 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3686 Diag(FD->getLocation(), 3687 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3688 << "dllimport"; 3689 FD->setInvalidDecl(); 3690 return DeclPtrTy::make(FD); 3691 } else { 3692 // If a symbol previously declared dllimport is later defined, the 3693 // attribute is ignored in subsequent references, and a warning is 3694 // emitted. 3695 Diag(FD->getLocation(), 3696 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3697 << FD->getNameAsCString() << "dllimport"; 3698 } 3699 } 3700 return DeclPtrTy::make(FD); 3701} 3702 3703Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3704 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3705} 3706 3707Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3708 bool IsInstantiation) { 3709 Decl *dcl = D.getAs<Decl>(); 3710 Stmt *Body = BodyArg.takeAs<Stmt>(); 3711 3712 FunctionDecl *FD = 0; 3713 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3714 if (FunTmpl) 3715 FD = FunTmpl->getTemplatedDecl(); 3716 else 3717 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3718 3719 if (FD) { 3720 FD->setBody(Body); 3721 if (FD->isMain()) 3722 // C and C++ allow for main to automagically return 0. 3723 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3724 FD->setHasImplicitReturnZero(true); 3725 else 3726 CheckFallThroughForFunctionDef(FD, Body); 3727 3728 if (!FD->isInvalidDecl()) 3729 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3730 3731 // C++ [basic.def.odr]p2: 3732 // [...] A virtual member function is used if it is not pure. [...] 3733 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3734 if (Method->isVirtual() && !Method->isPure()) 3735 MarkDeclarationReferenced(Method->getLocation(), Method); 3736 3737 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3738 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3739 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3740 MD->setBody(Body); 3741 CheckFallThroughForFunctionDef(MD, Body); 3742 MD->setEndLoc(Body->getLocEnd()); 3743 3744 if (!MD->isInvalidDecl()) 3745 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3746 } else { 3747 Body->Destroy(Context); 3748 return DeclPtrTy(); 3749 } 3750 if (!IsInstantiation) 3751 PopDeclContext(); 3752 3753 // Verify and clean out per-function state. 3754 3755 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3756 3757 // Check goto/label use. 3758 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3759 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3760 LabelStmt *L = I->second; 3761 3762 // Verify that we have no forward references left. If so, there was a goto 3763 // or address of a label taken, but no definition of it. Label fwd 3764 // definitions are indicated with a null substmt. 3765 if (L->getSubStmt() != 0) 3766 continue; 3767 3768 // Emit error. 3769 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3770 3771 // At this point, we have gotos that use the bogus label. Stitch it into 3772 // the function body so that they aren't leaked and that the AST is well 3773 // formed. 3774 if (Body == 0) { 3775 // The whole function wasn't parsed correctly, just delete this. 3776 L->Destroy(Context); 3777 continue; 3778 } 3779 3780 // Otherwise, the body is valid: we want to stitch the label decl into the 3781 // function somewhere so that it is properly owned and so that the goto 3782 // has a valid target. Do this by creating a new compound stmt with the 3783 // label in it. 3784 3785 // Give the label a sub-statement. 3786 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3787 3788 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3789 cast<CXXTryStmt>(Body)->getTryBlock() : 3790 cast<CompoundStmt>(Body); 3791 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3792 Elements.push_back(L); 3793 Compound->setStmts(Context, &Elements[0], Elements.size()); 3794 } 3795 FunctionLabelMap.clear(); 3796 3797 if (!Body) return D; 3798 3799 // Verify that that gotos and switch cases don't jump into scopes illegally. 3800 if (CurFunctionNeedsScopeChecking) 3801 DiagnoseInvalidJumps(Body); 3802 3803 // C++ constructors that have function-try-blocks can't have return 3804 // statements in the handlers of that block. (C++ [except.handle]p14) 3805 // Verify this. 3806 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3807 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3808 3809 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3810 computeBaseOrMembersToDestroy(Destructor); 3811 return D; 3812} 3813 3814/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3815/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3816NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3817 IdentifierInfo &II, Scope *S) { 3818 // Before we produce a declaration for an implicitly defined 3819 // function, see whether there was a locally-scoped declaration of 3820 // this name as a function or variable. If so, use that 3821 // (non-visible) declaration, and complain about it. 3822 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3823 = LocallyScopedExternalDecls.find(&II); 3824 if (Pos != LocallyScopedExternalDecls.end()) { 3825 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3826 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3827 return Pos->second; 3828 } 3829 3830 // Extension in C99. Legal in C90, but warn about it. 3831 if (getLangOptions().C99) 3832 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3833 else 3834 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3835 3836 // FIXME: handle stuff like: 3837 // void foo() { extern float X(); } 3838 // void bar() { X(); } <-- implicit decl for X in another scope. 3839 3840 // Set a Declarator for the implicit definition: int foo(); 3841 const char *Dummy; 3842 DeclSpec DS; 3843 unsigned DiagID; 3844 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3845 Error = Error; // Silence warning. 3846 assert(!Error && "Error setting up implicit decl!"); 3847 Declarator D(DS, Declarator::BlockContext); 3848 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3849 0, 0, false, SourceLocation(), 3850 false, 0,0,0, Loc, Loc, D), 3851 SourceLocation()); 3852 D.SetIdentifier(&II, Loc); 3853 3854 // Insert this function into translation-unit scope. 3855 3856 DeclContext *PrevDC = CurContext; 3857 CurContext = Context.getTranslationUnitDecl(); 3858 3859 FunctionDecl *FD = 3860 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3861 FD->setImplicit(); 3862 3863 CurContext = PrevDC; 3864 3865 AddKnownFunctionAttributes(FD); 3866 3867 return FD; 3868} 3869 3870/// \brief Adds any function attributes that we know a priori based on 3871/// the declaration of this function. 3872/// 3873/// These attributes can apply both to implicitly-declared builtins 3874/// (like __builtin___printf_chk) or to library-declared functions 3875/// like NSLog or printf. 3876void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3877 if (FD->isInvalidDecl()) 3878 return; 3879 3880 // If this is a built-in function, map its builtin attributes to 3881 // actual attributes. 3882 if (unsigned BuiltinID = FD->getBuiltinID()) { 3883 // Handle printf-formatting attributes. 3884 unsigned FormatIdx; 3885 bool HasVAListArg; 3886 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3887 if (!FD->getAttr<FormatAttr>()) 3888 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3889 HasVAListArg ? 0 : FormatIdx + 2)); 3890 } 3891 3892 // Mark const if we don't care about errno and that is the only 3893 // thing preventing the function from being const. This allows 3894 // IRgen to use LLVM intrinsics for such functions. 3895 if (!getLangOptions().MathErrno && 3896 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3897 if (!FD->getAttr<ConstAttr>()) 3898 FD->addAttr(::new (Context) ConstAttr()); 3899 } 3900 3901 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3902 FD->addAttr(::new (Context) NoReturnAttr()); 3903 } 3904 3905 IdentifierInfo *Name = FD->getIdentifier(); 3906 if (!Name) 3907 return; 3908 if ((!getLangOptions().CPlusPlus && 3909 FD->getDeclContext()->isTranslationUnit()) || 3910 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3911 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3912 LinkageSpecDecl::lang_c)) { 3913 // Okay: this could be a libc/libm/Objective-C function we know 3914 // about. 3915 } else 3916 return; 3917 3918 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3919 // FIXME: NSLog and NSLogv should be target specific 3920 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3921 // FIXME: We known better than our headers. 3922 const_cast<FormatAttr *>(Format)->setType("printf"); 3923 } else 3924 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3925 Name->isStr("NSLogv") ? 0 : 2)); 3926 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3927 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3928 // target-specific builtins, perhaps? 3929 if (!FD->getAttr<FormatAttr>()) 3930 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3931 Name->isStr("vasprintf") ? 0 : 3)); 3932 } 3933} 3934 3935TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3936 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3937 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3938 3939 // Scope manipulation handled by caller. 3940 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3941 D.getIdentifierLoc(), 3942 D.getIdentifier(), 3943 T); 3944 3945 if (const TagType *TT = T->getAs<TagType>()) { 3946 TagDecl *TD = TT->getDecl(); 3947 3948 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3949 // keep track of the TypedefDecl. 3950 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3951 TD->setTypedefForAnonDecl(NewTD); 3952 } 3953 3954 if (D.isInvalidType()) 3955 NewTD->setInvalidDecl(); 3956 return NewTD; 3957} 3958 3959 3960/// \brief Determine whether a tag with a given kind is acceptable 3961/// as a redeclaration of the given tag declaration. 3962/// 3963/// \returns true if the new tag kind is acceptable, false otherwise. 3964bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3965 TagDecl::TagKind NewTag, 3966 SourceLocation NewTagLoc, 3967 const IdentifierInfo &Name) { 3968 // C++ [dcl.type.elab]p3: 3969 // The class-key or enum keyword present in the 3970 // elaborated-type-specifier shall agree in kind with the 3971 // declaration to which the name in theelaborated-type-specifier 3972 // refers. This rule also applies to the form of 3973 // elaborated-type-specifier that declares a class-name or 3974 // friend class since it can be construed as referring to the 3975 // definition of the class. Thus, in any 3976 // elaborated-type-specifier, the enum keyword shall be used to 3977 // refer to an enumeration (7.2), the union class-keyshall be 3978 // used to refer to a union (clause 9), and either the class or 3979 // struct class-key shall be used to refer to a class (clause 9) 3980 // declared using the class or struct class-key. 3981 TagDecl::TagKind OldTag = Previous->getTagKind(); 3982 if (OldTag == NewTag) 3983 return true; 3984 3985 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3986 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3987 // Warn about the struct/class tag mismatch. 3988 bool isTemplate = false; 3989 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3990 isTemplate = Record->getDescribedClassTemplate(); 3991 3992 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3993 << (NewTag == TagDecl::TK_class) 3994 << isTemplate << &Name 3995 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3996 OldTag == TagDecl::TK_class? "class" : "struct"); 3997 Diag(Previous->getLocation(), diag::note_previous_use); 3998 return true; 3999 } 4000 return false; 4001} 4002 4003/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4004/// former case, Name will be non-null. In the later case, Name will be null. 4005/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4006/// reference/declaration/definition of a tag. 4007Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4008 SourceLocation KWLoc, const CXXScopeSpec &SS, 4009 IdentifierInfo *Name, SourceLocation NameLoc, 4010 AttributeList *Attr, AccessSpecifier AS, 4011 MultiTemplateParamsArg TemplateParameterLists, 4012 bool &OwnedDecl, bool &IsDependent) { 4013 // If this is not a definition, it must have a name. 4014 assert((Name != 0 || TUK == TUK_Definition) && 4015 "Nameless record must be a definition!"); 4016 4017 OwnedDecl = false; 4018 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4019 4020 if (TUK != TUK_Reference) { 4021 if (TemplateParameterList *TemplateParams 4022 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4023 (TemplateParameterList**)TemplateParameterLists.get(), 4024 TemplateParameterLists.size())) { 4025 if (TUK == TUK_Friend) { 4026 // When declaring a friend template, we do want to match the 4027 // template parameters to the scope specifier, but don't go so far 4028 // as to try to declare a new template. 4029 } else if (TemplateParams->size() > 0) { 4030 // This is a declaration or definition of a class template (which may 4031 // be a member of another template). 4032 OwnedDecl = false; 4033 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4034 SS, Name, NameLoc, Attr, 4035 TemplateParams, 4036 AS); 4037 TemplateParameterLists.release(); 4038 return Result.get(); 4039 } else { 4040 // FIXME: diagnose the extraneous 'template<>', once we recover 4041 // slightly better in ParseTemplate.cpp from bogus template 4042 // parameters. 4043 } 4044 } 4045 } 4046 4047 DeclContext *SearchDC = CurContext; 4048 DeclContext *DC = CurContext; 4049 NamedDecl *PrevDecl = 0; 4050 bool isStdBadAlloc = false; 4051 bool Invalid = false; 4052 4053 if (Name && SS.isNotEmpty()) { 4054 // We have a nested-name tag ('struct foo::bar'). 4055 4056 // Check for invalid 'foo::'. 4057 if (SS.isInvalid()) { 4058 Name = 0; 4059 goto CreateNewDecl; 4060 } 4061 4062 // If this is a friend or a reference to a class in a dependent 4063 // context, don't try to make a decl for it. 4064 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4065 DC = computeDeclContext(SS, false); 4066 if (!DC) { 4067 IsDependent = true; 4068 return DeclPtrTy(); 4069 } 4070 } 4071 4072 if (RequireCompleteDeclContext(SS)) 4073 return DeclPtrTy::make((Decl *)0); 4074 4075 DC = computeDeclContext(SS, true); 4076 SearchDC = DC; 4077 // Look-up name inside 'foo::'. 4078 PrevDecl 4079 = dyn_cast_or_null<TagDecl>( 4080 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4081 4082 // A tag 'foo::bar' must already exist. 4083 if (PrevDecl == 0) { 4084 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4085 Name = 0; 4086 Invalid = true; 4087 goto CreateNewDecl; 4088 } 4089 } else if (Name) { 4090 // If this is a named struct, check to see if there was a previous forward 4091 // declaration or definition. 4092 // FIXME: We're looking into outer scopes here, even when we 4093 // shouldn't be. Doing so can result in ambiguities that we 4094 // shouldn't be diagnosing. 4095 LookupResult R = LookupName(S, Name, LookupTagName, 4096 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4097 if (R.isAmbiguous()) { 4098 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4099 // FIXME: This is not best way to recover from case like: 4100 // 4101 // struct S s; 4102 // 4103 // causes needless "incomplete type" error later. 4104 Name = 0; 4105 PrevDecl = 0; 4106 Invalid = true; 4107 } else 4108 PrevDecl = R; 4109 4110 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4111 // FIXME: This makes sure that we ignore the contexts associated 4112 // with C structs, unions, and enums when looking for a matching 4113 // tag declaration or definition. See the similar lookup tweak 4114 // in Sema::LookupName; is there a better way to deal with this? 4115 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4116 SearchDC = SearchDC->getParent(); 4117 } 4118 } 4119 4120 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4121 // Maybe we will complain about the shadowed template parameter. 4122 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4123 // Just pretend that we didn't see the previous declaration. 4124 PrevDecl = 0; 4125 } 4126 4127 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4128 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4129 // This is a declaration of or a reference to "std::bad_alloc". 4130 isStdBadAlloc = true; 4131 4132 if (!PrevDecl && StdBadAlloc) { 4133 // std::bad_alloc has been implicitly declared (but made invisible to 4134 // name lookup). Fill in this implicit declaration as the previous 4135 // declaration, so that the declarations get chained appropriately. 4136 PrevDecl = StdBadAlloc; 4137 } 4138 } 4139 4140 if (PrevDecl) { 4141 // Check whether the previous declaration is usable. 4142 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4143 4144 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4145 // If this is a use of a previous tag, or if the tag is already declared 4146 // in the same scope (so that the definition/declaration completes or 4147 // rementions the tag), reuse the decl. 4148 if (TUK == TUK_Reference || TUK == TUK_Friend || 4149 isDeclInScope(PrevDecl, SearchDC, S)) { 4150 // Make sure that this wasn't declared as an enum and now used as a 4151 // struct or something similar. 4152 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4153 bool SafeToContinue 4154 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4155 Kind != TagDecl::TK_enum); 4156 if (SafeToContinue) 4157 Diag(KWLoc, diag::err_use_with_wrong_tag) 4158 << Name 4159 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4160 PrevTagDecl->getKindName()); 4161 else 4162 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4163 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4164 4165 if (SafeToContinue) 4166 Kind = PrevTagDecl->getTagKind(); 4167 else { 4168 // Recover by making this an anonymous redefinition. 4169 Name = 0; 4170 PrevDecl = 0; 4171 Invalid = true; 4172 } 4173 } 4174 4175 if (!Invalid) { 4176 // If this is a use, just return the declaration we found. 4177 4178 // FIXME: In the future, return a variant or some other clue 4179 // for the consumer of this Decl to know it doesn't own it. 4180 // For our current ASTs this shouldn't be a problem, but will 4181 // need to be changed with DeclGroups. 4182 if (TUK == TUK_Reference) 4183 return DeclPtrTy::make(PrevDecl); 4184 4185 // If this is a friend, make sure we create the new 4186 // declaration in the appropriate semantic context. 4187 if (TUK == TUK_Friend) 4188 SearchDC = PrevDecl->getDeclContext(); 4189 4190 // Diagnose attempts to redefine a tag. 4191 if (TUK == TUK_Definition) { 4192 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4193 Diag(NameLoc, diag::err_redefinition) << Name; 4194 Diag(Def->getLocation(), diag::note_previous_definition); 4195 // If this is a redefinition, recover by making this 4196 // struct be anonymous, which will make any later 4197 // references get the previous definition. 4198 Name = 0; 4199 PrevDecl = 0; 4200 Invalid = true; 4201 } else { 4202 // If the type is currently being defined, complain 4203 // about a nested redefinition. 4204 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4205 if (Tag->isBeingDefined()) { 4206 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4207 Diag(PrevTagDecl->getLocation(), 4208 diag::note_previous_definition); 4209 Name = 0; 4210 PrevDecl = 0; 4211 Invalid = true; 4212 } 4213 } 4214 4215 // Okay, this is definition of a previously declared or referenced 4216 // tag PrevDecl. We're going to create a new Decl for it. 4217 } 4218 } 4219 // If we get here we have (another) forward declaration or we 4220 // have a definition. Just create a new decl. 4221 4222 } else { 4223 // If we get here, this is a definition of a new tag type in a nested 4224 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4225 // new decl/type. We set PrevDecl to NULL so that the entities 4226 // have distinct types. 4227 PrevDecl = 0; 4228 } 4229 // If we get here, we're going to create a new Decl. If PrevDecl 4230 // is non-NULL, it's a definition of the tag declared by 4231 // PrevDecl. If it's NULL, we have a new definition. 4232 } else { 4233 // PrevDecl is a namespace, template, or anything else 4234 // that lives in the IDNS_Tag identifier namespace. 4235 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4236 // The tag name clashes with a namespace name, issue an error and 4237 // recover by making this tag be anonymous. 4238 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4239 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4240 Name = 0; 4241 PrevDecl = 0; 4242 Invalid = true; 4243 } else { 4244 // The existing declaration isn't relevant to us; we're in a 4245 // new scope, so clear out the previous declaration. 4246 PrevDecl = 0; 4247 } 4248 } 4249 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4250 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4251 // C++ [basic.scope.pdecl]p5: 4252 // -- for an elaborated-type-specifier of the form 4253 // 4254 // class-key identifier 4255 // 4256 // if the elaborated-type-specifier is used in the 4257 // decl-specifier-seq or parameter-declaration-clause of a 4258 // function defined in namespace scope, the identifier is 4259 // declared as a class-name in the namespace that contains 4260 // the declaration; otherwise, except as a friend 4261 // declaration, the identifier is declared in the smallest 4262 // non-class, non-function-prototype scope that contains the 4263 // declaration. 4264 // 4265 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4266 // C structs and unions. 4267 // 4268 // GNU C also supports this behavior as part of its incomplete 4269 // enum types extension, while GNU C++ does not. 4270 // 4271 // Find the context where we'll be declaring the tag. 4272 // FIXME: We would like to maintain the current DeclContext as the 4273 // lexical context, 4274 while (SearchDC->isRecord()) 4275 SearchDC = SearchDC->getParent(); 4276 4277 // Find the scope where we'll be declaring the tag. 4278 while (S->isClassScope() || 4279 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4280 ((S->getFlags() & Scope::DeclScope) == 0) || 4281 (S->getEntity() && 4282 ((DeclContext *)S->getEntity())->isTransparentContext())) 4283 S = S->getParent(); 4284 4285 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4286 // C++ [namespace.memdef]p3: 4287 // If a friend declaration in a non-local class first declares a 4288 // class or function, the friend class or function is a member of 4289 // the innermost enclosing namespace. 4290 while (!SearchDC->isFileContext()) 4291 SearchDC = SearchDC->getParent(); 4292 4293 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4294 while (S->getEntity() != SearchDC) 4295 S = S->getParent(); 4296 } 4297 4298CreateNewDecl: 4299 4300 // If there is an identifier, use the location of the identifier as the 4301 // location of the decl, otherwise use the location of the struct/union 4302 // keyword. 4303 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4304 4305 // Otherwise, create a new declaration. If there is a previous 4306 // declaration of the same entity, the two will be linked via 4307 // PrevDecl. 4308 TagDecl *New; 4309 4310 if (Kind == TagDecl::TK_enum) { 4311 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4312 // enum X { A, B, C } D; D should chain to X. 4313 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4314 cast_or_null<EnumDecl>(PrevDecl)); 4315 // If this is an undefined enum, warn. 4316 if (TUK != TUK_Definition && !Invalid) { 4317 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4318 : diag::ext_forward_ref_enum; 4319 Diag(Loc, DK); 4320 } 4321 } else { 4322 // struct/union/class 4323 4324 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4325 // struct X { int A; } D; D should chain to X. 4326 if (getLangOptions().CPlusPlus) { 4327 // FIXME: Look for a way to use RecordDecl for simple structs. 4328 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4329 cast_or_null<CXXRecordDecl>(PrevDecl)); 4330 4331 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4332 StdBadAlloc = cast<CXXRecordDecl>(New); 4333 } else 4334 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4335 cast_or_null<RecordDecl>(PrevDecl)); 4336 } 4337 4338 if (Kind != TagDecl::TK_enum) { 4339 // Handle #pragma pack: if the #pragma pack stack has non-default 4340 // alignment, make up a packed attribute for this decl. These 4341 // attributes are checked when the ASTContext lays out the 4342 // structure. 4343 // 4344 // It is important for implementing the correct semantics that this 4345 // happen here (in act on tag decl). The #pragma pack stack is 4346 // maintained as a result of parser callbacks which can occur at 4347 // many points during the parsing of a struct declaration (because 4348 // the #pragma tokens are effectively skipped over during the 4349 // parsing of the struct). 4350 if (unsigned Alignment = getPragmaPackAlignment()) 4351 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4352 } 4353 4354 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4355 // C++ [dcl.typedef]p3: 4356 // [...] Similarly, in a given scope, a class or enumeration 4357 // shall not be declared with the same name as a typedef-name 4358 // that is declared in that scope and refers to a type other 4359 // than the class or enumeration itself. 4360 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4361 TypedefDecl *PrevTypedef = 0; 4362 if (Lookup.getKind() == LookupResult::Found) 4363 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4364 4365 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4366 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4367 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4368 Diag(Loc, diag::err_tag_definition_of_typedef) 4369 << Context.getTypeDeclType(New) 4370 << PrevTypedef->getUnderlyingType(); 4371 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4372 Invalid = true; 4373 } 4374 } 4375 4376 if (Invalid) 4377 New->setInvalidDecl(); 4378 4379 if (Attr) 4380 ProcessDeclAttributeList(S, New, Attr); 4381 4382 // If we're declaring or defining a tag in function prototype scope 4383 // in C, note that this type can only be used within the function. 4384 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4385 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4386 4387 // Set the lexical context. If the tag has a C++ scope specifier, the 4388 // lexical context will be different from the semantic context. 4389 New->setLexicalDeclContext(CurContext); 4390 4391 // Mark this as a friend decl if applicable. 4392 if (TUK == TUK_Friend) 4393 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4394 4395 // Set the access specifier. 4396 if (!Invalid && TUK != TUK_Friend) 4397 SetMemberAccessSpecifier(New, PrevDecl, AS); 4398 4399 if (TUK == TUK_Definition) 4400 New->startDefinition(); 4401 4402 // If this has an identifier, add it to the scope stack. 4403 if (TUK == TUK_Friend) { 4404 // We might be replacing an existing declaration in the lookup tables; 4405 // if so, borrow its access specifier. 4406 if (PrevDecl) 4407 New->setAccess(PrevDecl->getAccess()); 4408 4409 // Friend tag decls are visible in fairly strange ways. 4410 if (!CurContext->isDependentContext()) { 4411 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4412 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4413 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4414 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4415 } 4416 } else if (Name) { 4417 S = getNonFieldDeclScope(S); 4418 PushOnScopeChains(New, S); 4419 } else { 4420 CurContext->addDecl(New); 4421 } 4422 4423 // If this is the C FILE type, notify the AST context. 4424 if (IdentifierInfo *II = New->getIdentifier()) 4425 if (!New->isInvalidDecl() && 4426 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4427 II->isStr("FILE")) 4428 Context.setFILEDecl(New); 4429 4430 OwnedDecl = true; 4431 return DeclPtrTy::make(New); 4432} 4433 4434void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4435 AdjustDeclIfTemplate(TagD); 4436 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4437 4438 // Enter the tag context. 4439 PushDeclContext(S, Tag); 4440 4441 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4442 FieldCollector->StartClass(); 4443 4444 if (Record->getIdentifier()) { 4445 // C++ [class]p2: 4446 // [...] The class-name is also inserted into the scope of the 4447 // class itself; this is known as the injected-class-name. For 4448 // purposes of access checking, the injected-class-name is treated 4449 // as if it were a public member name. 4450 CXXRecordDecl *InjectedClassName 4451 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4452 CurContext, Record->getLocation(), 4453 Record->getIdentifier(), 4454 Record->getTagKeywordLoc(), 4455 Record); 4456 InjectedClassName->setImplicit(); 4457 InjectedClassName->setAccess(AS_public); 4458 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4459 InjectedClassName->setDescribedClassTemplate(Template); 4460 PushOnScopeChains(InjectedClassName, S); 4461 assert(InjectedClassName->isInjectedClassName() && 4462 "Broken injected-class-name"); 4463 } 4464 } 4465} 4466 4467void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4468 SourceLocation RBraceLoc) { 4469 AdjustDeclIfTemplate(TagD); 4470 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4471 Tag->setRBraceLoc(RBraceLoc); 4472 4473 if (isa<CXXRecordDecl>(Tag)) 4474 FieldCollector->FinishClass(); 4475 4476 // Exit this scope of this tag's definition. 4477 PopDeclContext(); 4478 4479 // Notify the consumer that we've defined a tag. 4480 Consumer.HandleTagDeclDefinition(Tag); 4481} 4482 4483// Note that FieldName may be null for anonymous bitfields. 4484bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4485 QualType FieldTy, const Expr *BitWidth, 4486 bool *ZeroWidth) { 4487 // Default to true; that shouldn't confuse checks for emptiness 4488 if (ZeroWidth) 4489 *ZeroWidth = true; 4490 4491 // C99 6.7.2.1p4 - verify the field type. 4492 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4493 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4494 // Handle incomplete types with specific error. 4495 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4496 return true; 4497 if (FieldName) 4498 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4499 << FieldName << FieldTy << BitWidth->getSourceRange(); 4500 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4501 << FieldTy << BitWidth->getSourceRange(); 4502 } 4503 4504 // If the bit-width is type- or value-dependent, don't try to check 4505 // it now. 4506 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4507 return false; 4508 4509 llvm::APSInt Value; 4510 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4511 return true; 4512 4513 if (Value != 0 && ZeroWidth) 4514 *ZeroWidth = false; 4515 4516 // Zero-width bitfield is ok for anonymous field. 4517 if (Value == 0 && FieldName) 4518 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4519 4520 if (Value.isSigned() && Value.isNegative()) { 4521 if (FieldName) 4522 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4523 << FieldName << Value.toString(10); 4524 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4525 << Value.toString(10); 4526 } 4527 4528 if (!FieldTy->isDependentType()) { 4529 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4530 if (Value.getZExtValue() > TypeSize) { 4531 if (FieldName) 4532 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4533 << FieldName << (unsigned)TypeSize; 4534 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4535 << (unsigned)TypeSize; 4536 } 4537 } 4538 4539 return false; 4540} 4541 4542/// ActOnField - Each field of a struct/union/class is passed into this in order 4543/// to create a FieldDecl object for it. 4544Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4545 SourceLocation DeclStart, 4546 Declarator &D, ExprTy *BitfieldWidth) { 4547 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4548 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4549 AS_public); 4550 return DeclPtrTy::make(Res); 4551} 4552 4553/// HandleField - Analyze a field of a C struct or a C++ data member. 4554/// 4555FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4556 SourceLocation DeclStart, 4557 Declarator &D, Expr *BitWidth, 4558 AccessSpecifier AS) { 4559 IdentifierInfo *II = D.getIdentifier(); 4560 SourceLocation Loc = DeclStart; 4561 if (II) Loc = D.getIdentifierLoc(); 4562 4563 DeclaratorInfo *DInfo = 0; 4564 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4565 if (getLangOptions().CPlusPlus) 4566 CheckExtraCXXDefaultArguments(D); 4567 4568 DiagnoseFunctionSpecifiers(D); 4569 4570 if (D.getDeclSpec().isThreadSpecified()) 4571 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4572 4573 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4574 4575 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4576 // Maybe we will complain about the shadowed template parameter. 4577 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4578 // Just pretend that we didn't see the previous declaration. 4579 PrevDecl = 0; 4580 } 4581 4582 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4583 PrevDecl = 0; 4584 4585 bool Mutable 4586 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4587 SourceLocation TSSL = D.getSourceRange().getBegin(); 4588 FieldDecl *NewFD 4589 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4590 AS, PrevDecl, &D); 4591 if (NewFD->isInvalidDecl() && PrevDecl) { 4592 // Don't introduce NewFD into scope; there's already something 4593 // with the same name in the same scope. 4594 } else if (II) { 4595 PushOnScopeChains(NewFD, S); 4596 } else 4597 Record->addDecl(NewFD); 4598 4599 return NewFD; 4600} 4601 4602/// \brief Build a new FieldDecl and check its well-formedness. 4603/// 4604/// This routine builds a new FieldDecl given the fields name, type, 4605/// record, etc. \p PrevDecl should refer to any previous declaration 4606/// with the same name and in the same scope as the field to be 4607/// created. 4608/// 4609/// \returns a new FieldDecl. 4610/// 4611/// \todo The Declarator argument is a hack. It will be removed once 4612FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4613 DeclaratorInfo *DInfo, 4614 RecordDecl *Record, SourceLocation Loc, 4615 bool Mutable, Expr *BitWidth, 4616 SourceLocation TSSL, 4617 AccessSpecifier AS, NamedDecl *PrevDecl, 4618 Declarator *D) { 4619 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4620 bool InvalidDecl = false; 4621 if (D) InvalidDecl = D->isInvalidType(); 4622 4623 // If we receive a broken type, recover by assuming 'int' and 4624 // marking this declaration as invalid. 4625 if (T.isNull()) { 4626 InvalidDecl = true; 4627 T = Context.IntTy; 4628 } 4629 4630 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4631 // than a variably modified type. 4632 if (T->isVariablyModifiedType()) { 4633 bool SizeIsNegative; 4634 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4635 SizeIsNegative); 4636 if (!FixedTy.isNull()) { 4637 Diag(Loc, diag::warn_illegal_constant_array_size); 4638 T = FixedTy; 4639 } else { 4640 if (SizeIsNegative) 4641 Diag(Loc, diag::err_typecheck_negative_array_size); 4642 else 4643 Diag(Loc, diag::err_typecheck_field_variable_size); 4644 InvalidDecl = true; 4645 } 4646 } 4647 4648 // Fields can not have abstract class types 4649 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4650 AbstractFieldType)) 4651 InvalidDecl = true; 4652 4653 bool ZeroWidth = false; 4654 // If this is declared as a bit-field, check the bit-field. 4655 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4656 InvalidDecl = true; 4657 DeleteExpr(BitWidth); 4658 BitWidth = 0; 4659 ZeroWidth = false; 4660 } 4661 4662 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4663 BitWidth, Mutable); 4664 if (InvalidDecl) 4665 NewFD->setInvalidDecl(); 4666 4667 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4668 Diag(Loc, diag::err_duplicate_member) << II; 4669 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4670 NewFD->setInvalidDecl(); 4671 } 4672 4673 if (getLangOptions().CPlusPlus) { 4674 QualType EltTy = Context.getBaseElementType(T); 4675 4676 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4677 4678 if (!T->isPODType()) 4679 CXXRecord->setPOD(false); 4680 if (!ZeroWidth) 4681 CXXRecord->setEmpty(false); 4682 4683 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4684 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4685 4686 if (!RDecl->hasTrivialConstructor()) 4687 CXXRecord->setHasTrivialConstructor(false); 4688 if (!RDecl->hasTrivialCopyConstructor()) 4689 CXXRecord->setHasTrivialCopyConstructor(false); 4690 if (!RDecl->hasTrivialCopyAssignment()) 4691 CXXRecord->setHasTrivialCopyAssignment(false); 4692 if (!RDecl->hasTrivialDestructor()) 4693 CXXRecord->setHasTrivialDestructor(false); 4694 4695 // C++ 9.5p1: An object of a class with a non-trivial 4696 // constructor, a non-trivial copy constructor, a non-trivial 4697 // destructor, or a non-trivial copy assignment operator 4698 // cannot be a member of a union, nor can an array of such 4699 // objects. 4700 // TODO: C++0x alters this restriction significantly. 4701 if (Record->isUnion()) { 4702 // We check for copy constructors before constructors 4703 // because otherwise we'll never get complaints about 4704 // copy constructors. 4705 4706 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4707 4708 CXXSpecialMember member; 4709 if (!RDecl->hasTrivialCopyConstructor()) 4710 member = CXXCopyConstructor; 4711 else if (!RDecl->hasTrivialConstructor()) 4712 member = CXXDefaultConstructor; 4713 else if (!RDecl->hasTrivialCopyAssignment()) 4714 member = CXXCopyAssignment; 4715 else if (!RDecl->hasTrivialDestructor()) 4716 member = CXXDestructor; 4717 else 4718 member = invalid; 4719 4720 if (member != invalid) { 4721 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4722 DiagnoseNontrivial(RT, member); 4723 NewFD->setInvalidDecl(); 4724 } 4725 } 4726 } 4727 } 4728 4729 // FIXME: We need to pass in the attributes given an AST 4730 // representation, not a parser representation. 4731 if (D) 4732 // FIXME: What to pass instead of TUScope? 4733 ProcessDeclAttributes(TUScope, NewFD, *D); 4734 4735 if (T.isObjCGCWeak()) 4736 Diag(Loc, diag::warn_attribute_weak_on_field); 4737 4738 NewFD->setAccess(AS); 4739 4740 // C++ [dcl.init.aggr]p1: 4741 // An aggregate is an array or a class (clause 9) with [...] no 4742 // private or protected non-static data members (clause 11). 4743 // A POD must be an aggregate. 4744 if (getLangOptions().CPlusPlus && 4745 (AS == AS_private || AS == AS_protected)) { 4746 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4747 CXXRecord->setAggregate(false); 4748 CXXRecord->setPOD(false); 4749 } 4750 4751 return NewFD; 4752} 4753 4754/// DiagnoseNontrivial - Given that a class has a non-trivial 4755/// special member, figure out why. 4756void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4757 QualType QT(T, 0U); 4758 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4759 4760 // Check whether the member was user-declared. 4761 switch (member) { 4762 case CXXDefaultConstructor: 4763 if (RD->hasUserDeclaredConstructor()) { 4764 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4765 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4766 if (!ci->isImplicitlyDefined(Context)) { 4767 SourceLocation CtorLoc = ci->getLocation(); 4768 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4769 return; 4770 } 4771 4772 assert(0 && "found no user-declared constructors"); 4773 return; 4774 } 4775 break; 4776 4777 case CXXCopyConstructor: 4778 if (RD->hasUserDeclaredCopyConstructor()) { 4779 SourceLocation CtorLoc = 4780 RD->getCopyConstructor(Context, 0)->getLocation(); 4781 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4782 return; 4783 } 4784 break; 4785 4786 case CXXCopyAssignment: 4787 if (RD->hasUserDeclaredCopyAssignment()) { 4788 // FIXME: this should use the location of the copy 4789 // assignment, not the type. 4790 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4791 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4792 return; 4793 } 4794 break; 4795 4796 case CXXDestructor: 4797 if (RD->hasUserDeclaredDestructor()) { 4798 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4799 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4800 return; 4801 } 4802 break; 4803 } 4804 4805 typedef CXXRecordDecl::base_class_iterator base_iter; 4806 4807 // Virtual bases and members inhibit trivial copying/construction, 4808 // but not trivial destruction. 4809 if (member != CXXDestructor) { 4810 // Check for virtual bases. vbases includes indirect virtual bases, 4811 // so we just iterate through the direct bases. 4812 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4813 if (bi->isVirtual()) { 4814 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4815 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4816 return; 4817 } 4818 4819 // Check for virtual methods. 4820 typedef CXXRecordDecl::method_iterator meth_iter; 4821 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4822 ++mi) { 4823 if (mi->isVirtual()) { 4824 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4825 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4826 return; 4827 } 4828 } 4829 } 4830 4831 bool (CXXRecordDecl::*hasTrivial)() const; 4832 switch (member) { 4833 case CXXDefaultConstructor: 4834 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4835 case CXXCopyConstructor: 4836 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4837 case CXXCopyAssignment: 4838 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4839 case CXXDestructor: 4840 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4841 default: 4842 assert(0 && "unexpected special member"); return; 4843 } 4844 4845 // Check for nontrivial bases (and recurse). 4846 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4847 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4848 assert(BaseRT); 4849 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4850 if (!(BaseRecTy->*hasTrivial)()) { 4851 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4852 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4853 DiagnoseNontrivial(BaseRT, member); 4854 return; 4855 } 4856 } 4857 4858 // Check for nontrivial members (and recurse). 4859 typedef RecordDecl::field_iterator field_iter; 4860 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4861 ++fi) { 4862 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4863 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4864 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4865 4866 if (!(EltRD->*hasTrivial)()) { 4867 SourceLocation FLoc = (*fi)->getLocation(); 4868 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4869 DiagnoseNontrivial(EltRT, member); 4870 return; 4871 } 4872 } 4873 } 4874 4875 assert(0 && "found no explanation for non-trivial member"); 4876} 4877 4878/// TranslateIvarVisibility - Translate visibility from a token ID to an 4879/// AST enum value. 4880static ObjCIvarDecl::AccessControl 4881TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4882 switch (ivarVisibility) { 4883 default: assert(0 && "Unknown visitibility kind"); 4884 case tok::objc_private: return ObjCIvarDecl::Private; 4885 case tok::objc_public: return ObjCIvarDecl::Public; 4886 case tok::objc_protected: return ObjCIvarDecl::Protected; 4887 case tok::objc_package: return ObjCIvarDecl::Package; 4888 } 4889} 4890 4891/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4892/// in order to create an IvarDecl object for it. 4893Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4894 SourceLocation DeclStart, 4895 DeclPtrTy IntfDecl, 4896 Declarator &D, ExprTy *BitfieldWidth, 4897 tok::ObjCKeywordKind Visibility) { 4898 4899 IdentifierInfo *II = D.getIdentifier(); 4900 Expr *BitWidth = (Expr*)BitfieldWidth; 4901 SourceLocation Loc = DeclStart; 4902 if (II) Loc = D.getIdentifierLoc(); 4903 4904 // FIXME: Unnamed fields can be handled in various different ways, for 4905 // example, unnamed unions inject all members into the struct namespace! 4906 4907 DeclaratorInfo *DInfo = 0; 4908 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4909 4910 if (BitWidth) { 4911 // 6.7.2.1p3, 6.7.2.1p4 4912 if (VerifyBitField(Loc, II, T, BitWidth)) { 4913 D.setInvalidType(); 4914 DeleteExpr(BitWidth); 4915 BitWidth = 0; 4916 } 4917 } else { 4918 // Not a bitfield. 4919 4920 // validate II. 4921 4922 } 4923 4924 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4925 // than a variably modified type. 4926 if (T->isVariablyModifiedType()) { 4927 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4928 D.setInvalidType(); 4929 } 4930 4931 // Get the visibility (access control) for this ivar. 4932 ObjCIvarDecl::AccessControl ac = 4933 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4934 : ObjCIvarDecl::None; 4935 // Must set ivar's DeclContext to its enclosing interface. 4936 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4937 DeclContext *EnclosingContext; 4938 if (ObjCImplementationDecl *IMPDecl = 4939 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4940 // Case of ivar declared in an implementation. Context is that of its class. 4941 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4942 assert(IDecl && "No class- ActOnIvar"); 4943 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4944 } else 4945 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4946 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4947 4948 // Construct the decl. 4949 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4950 EnclosingContext, Loc, II, T, 4951 DInfo, ac, (Expr *)BitfieldWidth); 4952 4953 if (II) { 4954 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4955 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4956 && !isa<TagDecl>(PrevDecl)) { 4957 Diag(Loc, diag::err_duplicate_member) << II; 4958 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4959 NewID->setInvalidDecl(); 4960 } 4961 } 4962 4963 // Process attributes attached to the ivar. 4964 ProcessDeclAttributes(S, NewID, D); 4965 4966 if (D.isInvalidType()) 4967 NewID->setInvalidDecl(); 4968 4969 if (II) { 4970 // FIXME: When interfaces are DeclContexts, we'll need to add 4971 // these to the interface. 4972 S->AddDecl(DeclPtrTy::make(NewID)); 4973 IdResolver.AddDecl(NewID); 4974 } 4975 4976 return DeclPtrTy::make(NewID); 4977} 4978 4979void Sema::ActOnFields(Scope* S, 4980 SourceLocation RecLoc, DeclPtrTy RecDecl, 4981 DeclPtrTy *Fields, unsigned NumFields, 4982 SourceLocation LBrac, SourceLocation RBrac, 4983 AttributeList *Attr) { 4984 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4985 assert(EnclosingDecl && "missing record or interface decl"); 4986 4987 // If the decl this is being inserted into is invalid, then it may be a 4988 // redeclaration or some other bogus case. Don't try to add fields to it. 4989 if (EnclosingDecl->isInvalidDecl()) { 4990 // FIXME: Deallocate fields? 4991 return; 4992 } 4993 4994 4995 // Verify that all the fields are okay. 4996 unsigned NumNamedMembers = 0; 4997 llvm::SmallVector<FieldDecl*, 32> RecFields; 4998 4999 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5000 for (unsigned i = 0; i != NumFields; ++i) { 5001 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5002 5003 // Get the type for the field. 5004 Type *FDTy = FD->getType().getTypePtr(); 5005 5006 if (!FD->isAnonymousStructOrUnion()) { 5007 // Remember all fields written by the user. 5008 RecFields.push_back(FD); 5009 } 5010 5011 // If the field is already invalid for some reason, don't emit more 5012 // diagnostics about it. 5013 if (FD->isInvalidDecl()) 5014 continue; 5015 5016 // C99 6.7.2.1p2: 5017 // A structure or union shall not contain a member with 5018 // incomplete or function type (hence, a structure shall not 5019 // contain an instance of itself, but may contain a pointer to 5020 // an instance of itself), except that the last member of a 5021 // structure with more than one named member may have incomplete 5022 // array type; such a structure (and any union containing, 5023 // possibly recursively, a member that is such a structure) 5024 // shall not be a member of a structure or an element of an 5025 // array. 5026 if (FDTy->isFunctionType()) { 5027 // Field declared as a function. 5028 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5029 << FD->getDeclName(); 5030 FD->setInvalidDecl(); 5031 EnclosingDecl->setInvalidDecl(); 5032 continue; 5033 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5034 Record && Record->isStruct()) { 5035 // Flexible array member. 5036 if (NumNamedMembers < 1) { 5037 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5038 << FD->getDeclName(); 5039 FD->setInvalidDecl(); 5040 EnclosingDecl->setInvalidDecl(); 5041 continue; 5042 } 5043 // Okay, we have a legal flexible array member at the end of the struct. 5044 if (Record) 5045 Record->setHasFlexibleArrayMember(true); 5046 } else if (!FDTy->isDependentType() && 5047 RequireCompleteType(FD->getLocation(), FD->getType(), 5048 diag::err_field_incomplete)) { 5049 // Incomplete type 5050 FD->setInvalidDecl(); 5051 EnclosingDecl->setInvalidDecl(); 5052 continue; 5053 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5054 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5055 // If this is a member of a union, then entire union becomes "flexible". 5056 if (Record && Record->isUnion()) { 5057 Record->setHasFlexibleArrayMember(true); 5058 } else { 5059 // If this is a struct/class and this is not the last element, reject 5060 // it. Note that GCC supports variable sized arrays in the middle of 5061 // structures. 5062 if (i != NumFields-1) 5063 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5064 << FD->getDeclName() << FD->getType(); 5065 else { 5066 // We support flexible arrays at the end of structs in 5067 // other structs as an extension. 5068 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5069 << FD->getDeclName(); 5070 if (Record) 5071 Record->setHasFlexibleArrayMember(true); 5072 } 5073 } 5074 } 5075 if (Record && FDTTy->getDecl()->hasObjectMember()) 5076 Record->setHasObjectMember(true); 5077 } else if (FDTy->isObjCInterfaceType()) { 5078 /// A field cannot be an Objective-c object 5079 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5080 FD->setInvalidDecl(); 5081 EnclosingDecl->setInvalidDecl(); 5082 continue; 5083 } else if (getLangOptions().ObjC1 && 5084 getLangOptions().getGCMode() != LangOptions::NonGC && 5085 Record && 5086 (FD->getType()->isObjCObjectPointerType() || 5087 FD->getType().isObjCGCStrong())) 5088 Record->setHasObjectMember(true); 5089 // Keep track of the number of named members. 5090 if (FD->getIdentifier()) 5091 ++NumNamedMembers; 5092 } 5093 5094 // Okay, we successfully defined 'Record'. 5095 if (Record) { 5096 Record->completeDefinition(Context); 5097 } else { 5098 ObjCIvarDecl **ClsFields = 5099 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5100 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5101 ID->setIVarList(ClsFields, RecFields.size(), Context); 5102 ID->setLocEnd(RBrac); 5103 // Add ivar's to class's DeclContext. 5104 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5105 ClsFields[i]->setLexicalDeclContext(ID); 5106 ID->addDecl(ClsFields[i]); 5107 } 5108 // Must enforce the rule that ivars in the base classes may not be 5109 // duplicates. 5110 if (ID->getSuperClass()) { 5111 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5112 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5113 ObjCIvarDecl* Ivar = (*IVI); 5114 5115 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5116 ObjCIvarDecl* prevIvar = 5117 ID->getSuperClass()->lookupInstanceVariable(II); 5118 if (prevIvar) { 5119 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5120 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5121 } 5122 } 5123 } 5124 } 5125 } else if (ObjCImplementationDecl *IMPDecl = 5126 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5127 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5128 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5129 // Ivar declared in @implementation never belongs to the implementation. 5130 // Only it is in implementation's lexical context. 5131 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5132 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5133 } 5134 } 5135 5136 if (Attr) 5137 ProcessDeclAttributeList(S, Record, Attr); 5138} 5139 5140EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5141 EnumConstantDecl *LastEnumConst, 5142 SourceLocation IdLoc, 5143 IdentifierInfo *Id, 5144 ExprArg val) { 5145 Expr *Val = (Expr *)val.get(); 5146 5147 llvm::APSInt EnumVal(32); 5148 QualType EltTy; 5149 if (Val && !Val->isTypeDependent()) { 5150 // Make sure to promote the operand type to int. 5151 UsualUnaryConversions(Val); 5152 if (Val != val.get()) { 5153 val.release(); 5154 val = Val; 5155 } 5156 5157 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5158 SourceLocation ExpLoc; 5159 if (!Val->isValueDependent() && 5160 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5161 Val = 0; 5162 } else { 5163 EltTy = Val->getType(); 5164 } 5165 } 5166 5167 if (!Val) { 5168 if (LastEnumConst) { 5169 // Assign the last value + 1. 5170 EnumVal = LastEnumConst->getInitVal(); 5171 ++EnumVal; 5172 5173 // Check for overflow on increment. 5174 if (EnumVal < LastEnumConst->getInitVal()) 5175 Diag(IdLoc, diag::warn_enum_value_overflow); 5176 5177 EltTy = LastEnumConst->getType(); 5178 } else { 5179 // First value, set to zero. 5180 EltTy = Context.IntTy; 5181 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5182 } 5183 } 5184 5185 val.release(); 5186 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5187 Val, EnumVal); 5188} 5189 5190 5191Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5192 DeclPtrTy lastEnumConst, 5193 SourceLocation IdLoc, 5194 IdentifierInfo *Id, 5195 SourceLocation EqualLoc, ExprTy *val) { 5196 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5197 EnumConstantDecl *LastEnumConst = 5198 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5199 Expr *Val = static_cast<Expr*>(val); 5200 5201 // The scope passed in may not be a decl scope. Zip up the scope tree until 5202 // we find one that is. 5203 S = getNonFieldDeclScope(S); 5204 5205 // Verify that there isn't already something declared with this name in this 5206 // scope. 5207 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5208 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5209 // Maybe we will complain about the shadowed template parameter. 5210 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5211 // Just pretend that we didn't see the previous declaration. 5212 PrevDecl = 0; 5213 } 5214 5215 if (PrevDecl) { 5216 // When in C++, we may get a TagDecl with the same name; in this case the 5217 // enum constant will 'hide' the tag. 5218 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5219 "Received TagDecl when not in C++!"); 5220 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5221 if (isa<EnumConstantDecl>(PrevDecl)) 5222 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5223 else 5224 Diag(IdLoc, diag::err_redefinition) << Id; 5225 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5226 if (Val) Val->Destroy(Context); 5227 return DeclPtrTy(); 5228 } 5229 } 5230 5231 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5232 IdLoc, Id, Owned(Val)); 5233 5234 // Register this decl in the current scope stack. 5235 if (New) 5236 PushOnScopeChains(New, S); 5237 5238 return DeclPtrTy::make(New); 5239} 5240 5241void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5242 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5243 DeclPtrTy *Elements, unsigned NumElements, 5244 Scope *S, AttributeList *Attr) { 5245 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5246 QualType EnumType = Context.getTypeDeclType(Enum); 5247 5248 if (Attr) 5249 ProcessDeclAttributeList(S, Enum, Attr); 5250 5251 // TODO: If the result value doesn't fit in an int, it must be a long or long 5252 // long value. ISO C does not support this, but GCC does as an extension, 5253 // emit a warning. 5254 unsigned IntWidth = Context.Target.getIntWidth(); 5255 unsigned CharWidth = Context.Target.getCharWidth(); 5256 unsigned ShortWidth = Context.Target.getShortWidth(); 5257 5258 // Verify that all the values are okay, compute the size of the values, and 5259 // reverse the list. 5260 unsigned NumNegativeBits = 0; 5261 unsigned NumPositiveBits = 0; 5262 5263 // Keep track of whether all elements have type int. 5264 bool AllElementsInt = true; 5265 5266 for (unsigned i = 0; i != NumElements; ++i) { 5267 EnumConstantDecl *ECD = 5268 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5269 if (!ECD) continue; // Already issued a diagnostic. 5270 5271 // If the enum value doesn't fit in an int, emit an extension warning. 5272 const llvm::APSInt &InitVal = ECD->getInitVal(); 5273 assert(InitVal.getBitWidth() >= IntWidth && 5274 "Should have promoted value to int"); 5275 if (InitVal.getBitWidth() > IntWidth) { 5276 llvm::APSInt V(InitVal); 5277 V.trunc(IntWidth); 5278 V.extend(InitVal.getBitWidth()); 5279 if (V != InitVal) 5280 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5281 << InitVal.toString(10); 5282 } 5283 5284 // Keep track of the size of positive and negative values. 5285 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5286 NumPositiveBits = std::max(NumPositiveBits, 5287 (unsigned)InitVal.getActiveBits()); 5288 else 5289 NumNegativeBits = std::max(NumNegativeBits, 5290 (unsigned)InitVal.getMinSignedBits()); 5291 5292 // Keep track of whether every enum element has type int (very commmon). 5293 if (AllElementsInt) 5294 AllElementsInt = ECD->getType() == Context.IntTy; 5295 } 5296 5297 // Figure out the type that should be used for this enum. 5298 // FIXME: Support -fshort-enums. 5299 QualType BestType; 5300 unsigned BestWidth; 5301 5302 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5303 5304 if (NumNegativeBits) { 5305 // If there is a negative value, figure out the smallest integer type (of 5306 // int/long/longlong) that fits. 5307 // If it's packed, check also if it fits a char or a short. 5308 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5309 BestType = Context.SignedCharTy; 5310 BestWidth = CharWidth; 5311 } else if (Packed && NumNegativeBits <= ShortWidth && 5312 NumPositiveBits < ShortWidth) { 5313 BestType = Context.ShortTy; 5314 BestWidth = ShortWidth; 5315 } 5316 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5317 BestType = Context.IntTy; 5318 BestWidth = IntWidth; 5319 } else { 5320 BestWidth = Context.Target.getLongWidth(); 5321 5322 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5323 BestType = Context.LongTy; 5324 else { 5325 BestWidth = Context.Target.getLongLongWidth(); 5326 5327 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5328 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5329 BestType = Context.LongLongTy; 5330 } 5331 } 5332 } else { 5333 // If there is no negative value, figure out which of uint, ulong, ulonglong 5334 // fits. 5335 // If it's packed, check also if it fits a char or a short. 5336 if (Packed && NumPositiveBits <= CharWidth) { 5337 BestType = Context.UnsignedCharTy; 5338 BestWidth = CharWidth; 5339 } else if (Packed && NumPositiveBits <= ShortWidth) { 5340 BestType = Context.UnsignedShortTy; 5341 BestWidth = ShortWidth; 5342 } 5343 else if (NumPositiveBits <= IntWidth) { 5344 BestType = Context.UnsignedIntTy; 5345 BestWidth = IntWidth; 5346 } else if (NumPositiveBits <= 5347 (BestWidth = Context.Target.getLongWidth())) { 5348 BestType = Context.UnsignedLongTy; 5349 } else { 5350 BestWidth = Context.Target.getLongLongWidth(); 5351 assert(NumPositiveBits <= BestWidth && 5352 "How could an initializer get larger than ULL?"); 5353 BestType = Context.UnsignedLongLongTy; 5354 } 5355 } 5356 5357 // Loop over all of the enumerator constants, changing their types to match 5358 // the type of the enum if needed. 5359 for (unsigned i = 0; i != NumElements; ++i) { 5360 EnumConstantDecl *ECD = 5361 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5362 if (!ECD) continue; // Already issued a diagnostic. 5363 5364 // Standard C says the enumerators have int type, but we allow, as an 5365 // extension, the enumerators to be larger than int size. If each 5366 // enumerator value fits in an int, type it as an int, otherwise type it the 5367 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5368 // that X has type 'int', not 'unsigned'. 5369 if (ECD->getType() == Context.IntTy) { 5370 // Make sure the init value is signed. 5371 llvm::APSInt IV = ECD->getInitVal(); 5372 IV.setIsSigned(true); 5373 ECD->setInitVal(IV); 5374 5375 if (getLangOptions().CPlusPlus) 5376 // C++ [dcl.enum]p4: Following the closing brace of an 5377 // enum-specifier, each enumerator has the type of its 5378 // enumeration. 5379 ECD->setType(EnumType); 5380 continue; // Already int type. 5381 } 5382 5383 // Determine whether the value fits into an int. 5384 llvm::APSInt InitVal = ECD->getInitVal(); 5385 bool FitsInInt; 5386 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5387 FitsInInt = InitVal.getActiveBits() < IntWidth; 5388 else 5389 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5390 5391 // If it fits into an integer type, force it. Otherwise force it to match 5392 // the enum decl type. 5393 QualType NewTy; 5394 unsigned NewWidth; 5395 bool NewSign; 5396 if (FitsInInt) { 5397 NewTy = Context.IntTy; 5398 NewWidth = IntWidth; 5399 NewSign = true; 5400 } else if (ECD->getType() == BestType) { 5401 // Already the right type! 5402 if (getLangOptions().CPlusPlus) 5403 // C++ [dcl.enum]p4: Following the closing brace of an 5404 // enum-specifier, each enumerator has the type of its 5405 // enumeration. 5406 ECD->setType(EnumType); 5407 continue; 5408 } else { 5409 NewTy = BestType; 5410 NewWidth = BestWidth; 5411 NewSign = BestType->isSignedIntegerType(); 5412 } 5413 5414 // Adjust the APSInt value. 5415 InitVal.extOrTrunc(NewWidth); 5416 InitVal.setIsSigned(NewSign); 5417 ECD->setInitVal(InitVal); 5418 5419 // Adjust the Expr initializer and type. 5420 if (ECD->getInitExpr()) 5421 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5422 CastExpr::CK_Unknown, 5423 ECD->getInitExpr(), 5424 /*isLvalue=*/false)); 5425 if (getLangOptions().CPlusPlus) 5426 // C++ [dcl.enum]p4: Following the closing brace of an 5427 // enum-specifier, each enumerator has the type of its 5428 // enumeration. 5429 ECD->setType(EnumType); 5430 else 5431 ECD->setType(NewTy); 5432 } 5433 5434 Enum->completeDefinition(Context, BestType); 5435} 5436 5437Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5438 ExprArg expr) { 5439 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5440 5441 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5442 Loc, AsmString); 5443 CurContext->addDecl(New); 5444 return DeclPtrTy::make(New); 5445} 5446 5447void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5448 SourceLocation PragmaLoc, 5449 SourceLocation NameLoc) { 5450 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5451 5452 if (PrevDecl) { 5453 PrevDecl->addAttr(::new (Context) WeakAttr()); 5454 } else { 5455 (void)WeakUndeclaredIdentifiers.insert( 5456 std::pair<IdentifierInfo*,WeakInfo> 5457 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5458 } 5459} 5460 5461void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5462 IdentifierInfo* AliasName, 5463 SourceLocation PragmaLoc, 5464 SourceLocation NameLoc, 5465 SourceLocation AliasNameLoc) { 5466 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5467 WeakInfo W = WeakInfo(Name, NameLoc); 5468 5469 if (PrevDecl) { 5470 if (!PrevDecl->hasAttr<AliasAttr>()) 5471 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5472 DeclApplyPragmaWeak(TUScope, ND, W); 5473 } else { 5474 (void)WeakUndeclaredIdentifiers.insert( 5475 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5476 } 5477} 5478