SemaDecl.cpp revision 0f436560640a1cff5b6d96f80f540770f139453f
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/TargetInfo.h" 27#include "clang/Basic/SourceManager.h" 28// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 29#include "clang/Lex/Preprocessor.h" 30#include "clang/Lex/HeaderSearch.h" 31#include "llvm/ADT/BitVector.h" 32#include "llvm/ADT/STLExtras.h" 33#include <algorithm> 34#include <functional> 35#include <queue> 36using namespace clang; 37 38/// getDeclName - Return a pretty name for the specified decl if possible, or 39/// an empty string if not. This is used for pretty crash reporting. 40std::string Sema::getDeclName(DeclPtrTy d) { 41 Decl *D = d.getAs<Decl>(); 42 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 43 return DN->getQualifiedNameAsString(); 44 return ""; 45} 46 47Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 48 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 49} 50 51/// \brief If the identifier refers to a type name within this scope, 52/// return the declaration of that type. 53/// 54/// This routine performs ordinary name lookup of the identifier II 55/// within the given scope, with optional C++ scope specifier SS, to 56/// determine whether the name refers to a type. If so, returns an 57/// opaque pointer (actually a QualType) corresponding to that 58/// type. Otherwise, returns NULL. 59/// 60/// If name lookup results in an ambiguity, this routine will complain 61/// and then return NULL. 62Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 63 Scope *S, const CXXScopeSpec *SS) { 64 // C++ [temp.res]p3: 65 // A qualified-id that refers to a type and in which the 66 // nested-name-specifier depends on a template-parameter (14.6.2) 67 // shall be prefixed by the keyword typename to indicate that the 68 // qualified-id denotes a type, forming an 69 // elaborated-type-specifier (7.1.5.3). 70 // 71 // We therefore do not perform any name lookup if the result would 72 // refer to a member of an unknown specialization. 73 if (SS && isUnknownSpecialization(*SS)) 74 return 0; 75 76 LookupResult Result 77 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 78 79 NamedDecl *IIDecl = 0; 80 switch (Result.getKind()) { 81 case LookupResult::NotFound: 82 case LookupResult::FoundOverloaded: 83 return 0; 84 85 case LookupResult::AmbiguousBaseSubobjectTypes: 86 case LookupResult::AmbiguousBaseSubobjects: 87 case LookupResult::AmbiguousReference: { 88 // Look to see if we have a type anywhere in the list of results. 89 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 90 Res != ResEnd; ++Res) { 91 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 92 if (!IIDecl || 93 (*Res)->getLocation().getRawEncoding() < 94 IIDecl->getLocation().getRawEncoding()) 95 IIDecl = *Res; 96 } 97 } 98 99 if (!IIDecl) { 100 // None of the entities we found is a type, so there is no way 101 // to even assume that the result is a type. In this case, don't 102 // complain about the ambiguity. The parser will either try to 103 // perform this lookup again (e.g., as an object name), which 104 // will produce the ambiguity, or will complain that it expected 105 // a type name. 106 Result.Destroy(); 107 return 0; 108 } 109 110 // We found a type within the ambiguous lookup; diagnose the 111 // ambiguity and then return that type. This might be the right 112 // answer, or it might not be, but it suppresses any attempt to 113 // perform the name lookup again. 114 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 115 break; 116 } 117 118 case LookupResult::Found: 119 IIDecl = Result.getAsDecl(); 120 break; 121 } 122 123 if (IIDecl) { 124 QualType T; 125 126 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 127 // Check whether we can use this type 128 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 129 130 if (getLangOptions().CPlusPlus) { 131 // C++ [temp.local]p2: 132 // Within the scope of a class template specialization or 133 // partial specialization, when the injected-class-name is 134 // not followed by a <, it is equivalent to the 135 // injected-class-name followed by the template-argument s 136 // of the class template specialization or partial 137 // specialization enclosed in <>. 138 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 139 if (RD->isInjectedClassName()) 140 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 141 T = Template->getInjectedClassNameType(Context); 142 } 143 144 if (T.isNull()) 145 T = Context.getTypeDeclType(TD); 146 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 147 // Check whether we can use this interface. 148 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 149 150 T = Context.getObjCInterfaceType(IDecl); 151 } else 152 return 0; 153 154 if (SS) 155 T = getQualifiedNameType(*SS, T); 156 157 return T.getAsOpaquePtr(); 158 } 159 160 return 0; 161} 162 163/// isTagName() - This method is called *for error recovery purposes only* 164/// to determine if the specified name is a valid tag name ("struct foo"). If 165/// so, this returns the TST for the tag corresponding to it (TST_enum, 166/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 167/// where the user forgot to specify the tag. 168DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 169 // Do a tag name lookup in this scope. 170 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 171 if (R.getKind() == LookupResult::Found) 172 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 173 switch (TD->getTagKind()) { 174 case TagDecl::TK_struct: return DeclSpec::TST_struct; 175 case TagDecl::TK_union: return DeclSpec::TST_union; 176 case TagDecl::TK_class: return DeclSpec::TST_class; 177 case TagDecl::TK_enum: return DeclSpec::TST_enum; 178 } 179 } 180 181 return DeclSpec::TST_unspecified; 182} 183 184 185 186DeclContext *Sema::getContainingDC(DeclContext *DC) { 187 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 188 // A C++ out-of-line method will return to the file declaration context. 189 if (MD->isOutOfLine()) 190 return MD->getLexicalDeclContext(); 191 192 // A C++ inline method is parsed *after* the topmost class it was declared 193 // in is fully parsed (it's "complete"). 194 // The parsing of a C++ inline method happens at the declaration context of 195 // the topmost (non-nested) class it is lexically declared in. 196 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 197 DC = MD->getParent(); 198 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 199 DC = RD; 200 201 // Return the declaration context of the topmost class the inline method is 202 // declared in. 203 return DC; 204 } 205 206 if (isa<ObjCMethodDecl>(DC)) 207 return Context.getTranslationUnitDecl(); 208 209 return DC->getLexicalParent(); 210} 211 212void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 213 assert(getContainingDC(DC) == CurContext && 214 "The next DeclContext should be lexically contained in the current one."); 215 CurContext = DC; 216 S->setEntity(DC); 217} 218 219void Sema::PopDeclContext() { 220 assert(CurContext && "DeclContext imbalance!"); 221 222 CurContext = getContainingDC(CurContext); 223} 224 225/// EnterDeclaratorContext - Used when we must lookup names in the context 226/// of a declarator's nested name specifier. 227void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 228 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 229 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 230 CurContext = DC; 231 assert(CurContext && "No context?"); 232 S->setEntity(CurContext); 233} 234 235void Sema::ExitDeclaratorContext(Scope *S) { 236 S->setEntity(PreDeclaratorDC); 237 PreDeclaratorDC = 0; 238 239 // Reset CurContext to the nearest enclosing context. 240 while (!S->getEntity() && S->getParent()) 241 S = S->getParent(); 242 CurContext = static_cast<DeclContext*>(S->getEntity()); 243 assert(CurContext && "No context?"); 244} 245 246/// \brief Determine whether we allow overloading of the function 247/// PrevDecl with another declaration. 248/// 249/// This routine determines whether overloading is possible, not 250/// whether some new function is actually an overload. It will return 251/// true in C++ (where we can always provide overloads) or, as an 252/// extension, in C when the previous function is already an 253/// overloaded function declaration or has the "overloadable" 254/// attribute. 255static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 256 if (Context.getLangOptions().CPlusPlus) 257 return true; 258 259 if (isa<OverloadedFunctionDecl>(PrevDecl)) 260 return true; 261 262 return PrevDecl->getAttr<OverloadableAttr>() != 0; 263} 264 265/// Add this decl to the scope shadowed decl chains. 266void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 267 // Move up the scope chain until we find the nearest enclosing 268 // non-transparent context. The declaration will be introduced into this 269 // scope. 270 while (S->getEntity() && 271 ((DeclContext *)S->getEntity())->isTransparentContext()) 272 S = S->getParent(); 273 274 S->AddDecl(DeclPtrTy::make(D)); 275 276 // Add scoped declarations into their context, so that they can be 277 // found later. Declarations without a context won't be inserted 278 // into any context. 279 CurContext->addDecl(D); 280 281 // C++ [basic.scope]p4: 282 // -- exactly one declaration shall declare a class name or 283 // enumeration name that is not a typedef name and the other 284 // declarations shall all refer to the same object or 285 // enumerator, or all refer to functions and function templates; 286 // in this case the class name or enumeration name is hidden. 287 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 288 // We are pushing the name of a tag (enum or class). 289 if (CurContext->getLookupContext() 290 == TD->getDeclContext()->getLookupContext()) { 291 // We're pushing the tag into the current context, which might 292 // require some reshuffling in the identifier resolver. 293 IdentifierResolver::iterator 294 I = IdResolver.begin(TD->getDeclName()), 295 IEnd = IdResolver.end(); 296 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 297 NamedDecl *PrevDecl = *I; 298 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 299 PrevDecl = *I, ++I) { 300 if (TD->declarationReplaces(*I)) { 301 // This is a redeclaration. Remove it from the chain and 302 // break out, so that we'll add in the shadowed 303 // declaration. 304 S->RemoveDecl(DeclPtrTy::make(*I)); 305 if (PrevDecl == *I) { 306 IdResolver.RemoveDecl(*I); 307 IdResolver.AddDecl(TD); 308 return; 309 } else { 310 IdResolver.RemoveDecl(*I); 311 break; 312 } 313 } 314 } 315 316 // There is already a declaration with the same name in the same 317 // scope, which is not a tag declaration. It must be found 318 // before we find the new declaration, so insert the new 319 // declaration at the end of the chain. 320 IdResolver.AddShadowedDecl(TD, PrevDecl); 321 322 return; 323 } 324 } 325 } else if ((isa<FunctionDecl>(D) && 326 AllowOverloadingOfFunction(D, Context)) || 327 isa<FunctionTemplateDecl>(D)) { 328 // We are pushing the name of a function or function template, 329 // which might be an overloaded name. 330 IdentifierResolver::iterator Redecl 331 = std::find_if(IdResolver.begin(D->getDeclName()), 332 IdResolver.end(), 333 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 334 D)); 335 if (Redecl != IdResolver.end() && 336 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 337 // There is already a declaration of a function on our 338 // IdResolver chain. Replace it with this declaration. 339 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 340 IdResolver.RemoveDecl(*Redecl); 341 } 342 } else if (isa<ObjCInterfaceDecl>(D)) { 343 // We're pushing an Objective-C interface into the current 344 // context. If there is already an alias declaration, remove it first. 345 for (IdentifierResolver::iterator 346 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 347 I != IEnd; ++I) { 348 if (isa<ObjCCompatibleAliasDecl>(*I)) { 349 S->RemoveDecl(DeclPtrTy::make(*I)); 350 IdResolver.RemoveDecl(*I); 351 break; 352 } 353 } 354 } 355 356 IdResolver.AddDecl(D); 357} 358 359void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 360 if (S->decl_empty()) return; 361 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 362 "Scope shouldn't contain decls!"); 363 364 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 365 I != E; ++I) { 366 Decl *TmpD = (*I).getAs<Decl>(); 367 assert(TmpD && "This decl didn't get pushed??"); 368 369 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 370 NamedDecl *D = cast<NamedDecl>(TmpD); 371 372 if (!D->getDeclName()) continue; 373 374 // Remove this name from our lexical scope. 375 IdResolver.RemoveDecl(D); 376 } 377} 378 379/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 380/// return 0 if one not found. 381ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 382 // The third "scope" argument is 0 since we aren't enabling lazy built-in 383 // creation from this context. 384 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 385 386 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 387} 388 389/// getNonFieldDeclScope - Retrieves the innermost scope, starting 390/// from S, where a non-field would be declared. This routine copes 391/// with the difference between C and C++ scoping rules in structs and 392/// unions. For example, the following code is well-formed in C but 393/// ill-formed in C++: 394/// @code 395/// struct S6 { 396/// enum { BAR } e; 397/// }; 398/// 399/// void test_S6() { 400/// struct S6 a; 401/// a.e = BAR; 402/// } 403/// @endcode 404/// For the declaration of BAR, this routine will return a different 405/// scope. The scope S will be the scope of the unnamed enumeration 406/// within S6. In C++, this routine will return the scope associated 407/// with S6, because the enumeration's scope is a transparent 408/// context but structures can contain non-field names. In C, this 409/// routine will return the translation unit scope, since the 410/// enumeration's scope is a transparent context and structures cannot 411/// contain non-field names. 412Scope *Sema::getNonFieldDeclScope(Scope *S) { 413 while (((S->getFlags() & Scope::DeclScope) == 0) || 414 (S->getEntity() && 415 ((DeclContext *)S->getEntity())->isTransparentContext()) || 416 (S->isClassScope() && !getLangOptions().CPlusPlus)) 417 S = S->getParent(); 418 return S; 419} 420 421void Sema::InitBuiltinVaListType() { 422 if (!Context.getBuiltinVaListType().isNull()) 423 return; 424 425 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 426 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 427 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 428 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 429} 430 431/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 432/// file scope. lazily create a decl for it. ForRedeclaration is true 433/// if we're creating this built-in in anticipation of redeclaring the 434/// built-in. 435NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 436 Scope *S, bool ForRedeclaration, 437 SourceLocation Loc) { 438 Builtin::ID BID = (Builtin::ID)bid; 439 440 if (Context.BuiltinInfo.hasVAListUse(BID)) 441 InitBuiltinVaListType(); 442 443 ASTContext::GetBuiltinTypeError Error; 444 QualType R = Context.GetBuiltinType(BID, Error); 445 switch (Error) { 446 case ASTContext::GE_None: 447 // Okay 448 break; 449 450 case ASTContext::GE_Missing_stdio: 451 if (ForRedeclaration) 452 Diag(Loc, diag::err_implicit_decl_requires_stdio) 453 << Context.BuiltinInfo.GetName(BID); 454 return 0; 455 456 case ASTContext::GE_Missing_setjmp: 457 if (ForRedeclaration) 458 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 459 << Context.BuiltinInfo.GetName(BID); 460 return 0; 461 } 462 463 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 464 Diag(Loc, diag::ext_implicit_lib_function_decl) 465 << Context.BuiltinInfo.GetName(BID) 466 << R; 467 if (Context.BuiltinInfo.getHeaderName(BID) && 468 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 469 != Diagnostic::Ignored) 470 Diag(Loc, diag::note_please_include_header) 471 << Context.BuiltinInfo.getHeaderName(BID) 472 << Context.BuiltinInfo.GetName(BID); 473 } 474 475 FunctionDecl *New = FunctionDecl::Create(Context, 476 Context.getTranslationUnitDecl(), 477 Loc, II, R, 478 FunctionDecl::Extern, false, 479 /*hasPrototype=*/true); 480 New->setImplicit(); 481 482 // Create Decl objects for each parameter, adding them to the 483 // FunctionDecl. 484 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 485 llvm::SmallVector<ParmVarDecl*, 16> Params; 486 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 487 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 488 FT->getArgType(i), VarDecl::None, 0)); 489 New->setParams(Context, Params.data(), Params.size()); 490 } 491 492 AddKnownFunctionAttributes(New); 493 494 // TUScope is the translation-unit scope to insert this function into. 495 // FIXME: This is hideous. We need to teach PushOnScopeChains to 496 // relate Scopes to DeclContexts, and probably eliminate CurContext 497 // entirely, but we're not there yet. 498 DeclContext *SavedContext = CurContext; 499 CurContext = Context.getTranslationUnitDecl(); 500 PushOnScopeChains(New, TUScope); 501 CurContext = SavedContext; 502 return New; 503} 504 505/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 506/// everything from the standard library is defined. 507NamespaceDecl *Sema::GetStdNamespace() { 508 if (!StdNamespace) { 509 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 510 DeclContext *Global = Context.getTranslationUnitDecl(); 511 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 512 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 513 } 514 return StdNamespace; 515} 516 517/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 518/// same name and scope as a previous declaration 'Old'. Figure out 519/// how to resolve this situation, merging decls or emitting 520/// diagnostics as appropriate. If there was an error, set New to be invalid. 521/// 522void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 523 // If either decl is known invalid already, set the new one to be invalid and 524 // don't bother doing any merging checks. 525 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 526 return New->setInvalidDecl(); 527 528 // Allow multiple definitions for ObjC built-in typedefs. 529 // FIXME: Verify the underlying types are equivalent! 530 if (getLangOptions().ObjC1) { 531 const IdentifierInfo *TypeID = New->getIdentifier(); 532 switch (TypeID->getLength()) { 533 default: break; 534 case 2: 535 if (!TypeID->isStr("id")) 536 break; 537 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 538 // Install the built-in type for 'id', ignoring the current definition. 539 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 540 return; 541 case 5: 542 if (!TypeID->isStr("Class")) 543 break; 544 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 545 // Install the built-in type for 'Class', ignoring the current definition. 546 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 547 return; 548 case 3: 549 if (!TypeID->isStr("SEL")) 550 break; 551 Context.setObjCSelType(Context.getTypeDeclType(New)); 552 return; 553 case 8: 554 if (!TypeID->isStr("Protocol")) 555 break; 556 Context.setObjCProtoType(New->getUnderlyingType()); 557 return; 558 } 559 // Fall through - the typedef name was not a builtin type. 560 } 561 // Verify the old decl was also a type. 562 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 563 if (!Old) { 564 Diag(New->getLocation(), diag::err_redefinition_different_kind) 565 << New->getDeclName(); 566 if (OldD->getLocation().isValid()) 567 Diag(OldD->getLocation(), diag::note_previous_definition); 568 return New->setInvalidDecl(); 569 } 570 571 // Determine the "old" type we'll use for checking and diagnostics. 572 QualType OldType; 573 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 574 OldType = OldTypedef->getUnderlyingType(); 575 else 576 OldType = Context.getTypeDeclType(Old); 577 578 // If the typedef types are not identical, reject them in all languages and 579 // with any extensions enabled. 580 581 if (OldType != New->getUnderlyingType() && 582 Context.getCanonicalType(OldType) != 583 Context.getCanonicalType(New->getUnderlyingType())) { 584 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 585 << New->getUnderlyingType() << OldType; 586 if (Old->getLocation().isValid()) 587 Diag(Old->getLocation(), diag::note_previous_definition); 588 return New->setInvalidDecl(); 589 } 590 591 if (getLangOptions().Microsoft) 592 return; 593 594 // C++ [dcl.typedef]p2: 595 // In a given non-class scope, a typedef specifier can be used to 596 // redefine the name of any type declared in that scope to refer 597 // to the type to which it already refers. 598 if (getLangOptions().CPlusPlus) { 599 if (!isa<CXXRecordDecl>(CurContext)) 600 return; 601 Diag(New->getLocation(), diag::err_redefinition) 602 << New->getDeclName(); 603 Diag(Old->getLocation(), diag::note_previous_definition); 604 return New->setInvalidDecl(); 605 } 606 607 // If we have a redefinition of a typedef in C, emit a warning. This warning 608 // is normally mapped to an error, but can be controlled with 609 // -Wtypedef-redefinition. If either the original or the redefinition is 610 // in a system header, don't emit this for compatibility with GCC. 611 if (PP.getDiagnostics().getSuppressSystemWarnings() && 612 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 613 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 614 return; 615 616 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 617 << New->getDeclName(); 618 Diag(Old->getLocation(), diag::note_previous_definition); 619 return; 620} 621 622/// DeclhasAttr - returns true if decl Declaration already has the target 623/// attribute. 624static bool 625DeclHasAttr(const Decl *decl, const Attr *target) { 626 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 627 if (attr->getKind() == target->getKind()) 628 return true; 629 630 return false; 631} 632 633/// MergeAttributes - append attributes from the Old decl to the New one. 634static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 635 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 636 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 637 Attr *NewAttr = attr->clone(C); 638 NewAttr->setInherited(true); 639 New->addAttr(NewAttr); 640 } 641 } 642} 643 644/// Used in MergeFunctionDecl to keep track of function parameters in 645/// C. 646struct GNUCompatibleParamWarning { 647 ParmVarDecl *OldParm; 648 ParmVarDecl *NewParm; 649 QualType PromotedType; 650}; 651 652/// MergeFunctionDecl - We just parsed a function 'New' from 653/// declarator D which has the same name and scope as a previous 654/// declaration 'Old'. Figure out how to resolve this situation, 655/// merging decls or emitting diagnostics as appropriate. 656/// 657/// In C++, New and Old must be declarations that are not 658/// overloaded. Use IsOverload to determine whether New and Old are 659/// overloaded, and to select the Old declaration that New should be 660/// merged with. 661/// 662/// Returns true if there was an error, false otherwise. 663bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 664 assert(!isa<OverloadedFunctionDecl>(OldD) && 665 "Cannot merge with an overloaded function declaration"); 666 667 // Verify the old decl was also a function. 668 FunctionDecl *Old = 0; 669 if (FunctionTemplateDecl *OldFunctionTemplate 670 = dyn_cast<FunctionTemplateDecl>(OldD)) 671 Old = OldFunctionTemplate->getTemplatedDecl(); 672 else 673 Old = dyn_cast<FunctionDecl>(OldD); 674 if (!Old) { 675 Diag(New->getLocation(), diag::err_redefinition_different_kind) 676 << New->getDeclName(); 677 Diag(OldD->getLocation(), diag::note_previous_definition); 678 return true; 679 } 680 681 // Determine whether the previous declaration was a definition, 682 // implicit declaration, or a declaration. 683 diag::kind PrevDiag; 684 if (Old->isThisDeclarationADefinition()) 685 PrevDiag = diag::note_previous_definition; 686 else if (Old->isImplicit()) 687 PrevDiag = diag::note_previous_implicit_declaration; 688 else 689 PrevDiag = diag::note_previous_declaration; 690 691 QualType OldQType = Context.getCanonicalType(Old->getType()); 692 QualType NewQType = Context.getCanonicalType(New->getType()); 693 694 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 695 New->getStorageClass() == FunctionDecl::Static && 696 Old->getStorageClass() != FunctionDecl::Static) { 697 Diag(New->getLocation(), diag::err_static_non_static) 698 << New; 699 Diag(Old->getLocation(), PrevDiag); 700 return true; 701 } 702 703 if (getLangOptions().CPlusPlus) { 704 // (C++98 13.1p2): 705 // Certain function declarations cannot be overloaded: 706 // -- Function declarations that differ only in the return type 707 // cannot be overloaded. 708 QualType OldReturnType 709 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 710 QualType NewReturnType 711 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 712 if (OldReturnType != NewReturnType) { 713 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 714 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 715 return true; 716 } 717 718 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 719 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 720 if (OldMethod && NewMethod && 721 NewMethod->getLexicalDeclContext()->isRecord()) { 722 // -- Member function declarations with the same name and the 723 // same parameter types cannot be overloaded if any of them 724 // is a static member function declaration. 725 if (OldMethod->isStatic() || NewMethod->isStatic()) { 726 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 727 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 728 return true; 729 } 730 731 // C++ [class.mem]p1: 732 // [...] A member shall not be declared twice in the 733 // member-specification, except that a nested class or member 734 // class template can be declared and then later defined. 735 unsigned NewDiag; 736 if (isa<CXXConstructorDecl>(OldMethod)) 737 NewDiag = diag::err_constructor_redeclared; 738 else if (isa<CXXDestructorDecl>(NewMethod)) 739 NewDiag = diag::err_destructor_redeclared; 740 else if (isa<CXXConversionDecl>(NewMethod)) 741 NewDiag = diag::err_conv_function_redeclared; 742 else 743 NewDiag = diag::err_member_redeclared; 744 745 Diag(New->getLocation(), NewDiag); 746 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 747 } 748 749 // (C++98 8.3.5p3): 750 // All declarations for a function shall agree exactly in both the 751 // return type and the parameter-type-list. 752 if (OldQType == NewQType) 753 return MergeCompatibleFunctionDecls(New, Old); 754 755 // Fall through for conflicting redeclarations and redefinitions. 756 } 757 758 // C: Function types need to be compatible, not identical. This handles 759 // duplicate function decls like "void f(int); void f(enum X);" properly. 760 if (!getLangOptions().CPlusPlus && 761 Context.typesAreCompatible(OldQType, NewQType)) { 762 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 763 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 764 const FunctionProtoType *OldProto = 0; 765 if (isa<FunctionNoProtoType>(NewFuncType) && 766 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 767 // The old declaration provided a function prototype, but the 768 // new declaration does not. Merge in the prototype. 769 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 770 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 771 OldProto->arg_type_end()); 772 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 773 ParamTypes.data(), ParamTypes.size(), 774 OldProto->isVariadic(), 775 OldProto->getTypeQuals()); 776 New->setType(NewQType); 777 New->setHasInheritedPrototype(); 778 779 // Synthesize a parameter for each argument type. 780 llvm::SmallVector<ParmVarDecl*, 16> Params; 781 for (FunctionProtoType::arg_type_iterator 782 ParamType = OldProto->arg_type_begin(), 783 ParamEnd = OldProto->arg_type_end(); 784 ParamType != ParamEnd; ++ParamType) { 785 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 786 SourceLocation(), 0, 787 *ParamType, VarDecl::None, 788 0); 789 Param->setImplicit(); 790 Params.push_back(Param); 791 } 792 793 New->setParams(Context, Params.data(), Params.size()); 794 } 795 796 return MergeCompatibleFunctionDecls(New, Old); 797 } 798 799 // GNU C permits a K&R definition to follow a prototype declaration 800 // if the declared types of the parameters in the K&R definition 801 // match the types in the prototype declaration, even when the 802 // promoted types of the parameters from the K&R definition differ 803 // from the types in the prototype. GCC then keeps the types from 804 // the prototype. 805 // 806 // If a variadic prototype is followed by a non-variadic K&R definition, 807 // the K&R definition becomes variadic. This is sort of an edge case, but 808 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 809 // C99 6.9.1p8. 810 if (!getLangOptions().CPlusPlus && 811 Old->hasPrototype() && !New->hasPrototype() && 812 New->getType()->getAsFunctionProtoType() && 813 Old->getNumParams() == New->getNumParams()) { 814 llvm::SmallVector<QualType, 16> ArgTypes; 815 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 816 const FunctionProtoType *OldProto 817 = Old->getType()->getAsFunctionProtoType(); 818 const FunctionProtoType *NewProto 819 = New->getType()->getAsFunctionProtoType(); 820 821 // Determine whether this is the GNU C extension. 822 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 823 NewProto->getResultType()); 824 bool LooseCompatible = !MergedReturn.isNull(); 825 for (unsigned Idx = 0, End = Old->getNumParams(); 826 LooseCompatible && Idx != End; ++Idx) { 827 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 828 ParmVarDecl *NewParm = New->getParamDecl(Idx); 829 if (Context.typesAreCompatible(OldParm->getType(), 830 NewProto->getArgType(Idx))) { 831 ArgTypes.push_back(NewParm->getType()); 832 } else if (Context.typesAreCompatible(OldParm->getType(), 833 NewParm->getType())) { 834 GNUCompatibleParamWarning Warn 835 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 836 Warnings.push_back(Warn); 837 ArgTypes.push_back(NewParm->getType()); 838 } else 839 LooseCompatible = false; 840 } 841 842 if (LooseCompatible) { 843 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 844 Diag(Warnings[Warn].NewParm->getLocation(), 845 diag::ext_param_promoted_not_compatible_with_prototype) 846 << Warnings[Warn].PromotedType 847 << Warnings[Warn].OldParm->getType(); 848 Diag(Warnings[Warn].OldParm->getLocation(), 849 diag::note_previous_declaration); 850 } 851 852 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 853 ArgTypes.size(), 854 OldProto->isVariadic(), 0)); 855 return MergeCompatibleFunctionDecls(New, Old); 856 } 857 858 // Fall through to diagnose conflicting types. 859 } 860 861 // A function that has already been declared has been redeclared or defined 862 // with a different type- show appropriate diagnostic 863 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 864 // The user has declared a builtin function with an incompatible 865 // signature. 866 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 867 // The function the user is redeclaring is a library-defined 868 // function like 'malloc' or 'printf'. Warn about the 869 // redeclaration, then pretend that we don't know about this 870 // library built-in. 871 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 872 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 873 << Old << Old->getType(); 874 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 875 Old->setInvalidDecl(); 876 return false; 877 } 878 879 PrevDiag = diag::note_previous_builtin_declaration; 880 } 881 882 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 883 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 884 return true; 885} 886 887/// \brief Completes the merge of two function declarations that are 888/// known to be compatible. 889/// 890/// This routine handles the merging of attributes and other 891/// properties of function declarations form the old declaration to 892/// the new declaration, once we know that New is in fact a 893/// redeclaration of Old. 894/// 895/// \returns false 896bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 897 // Merge the attributes 898 MergeAttributes(New, Old, Context); 899 900 // Merge the storage class. 901 if (Old->getStorageClass() != FunctionDecl::Extern) 902 New->setStorageClass(Old->getStorageClass()); 903 904 // Merge "inline" 905 if (Old->isInline()) 906 New->setInline(true); 907 908 // If this function declaration by itself qualifies as a C99 inline 909 // definition (C99 6.7.4p6), but the previous definition did not, 910 // then the function is not a C99 inline definition. 911 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 912 New->setC99InlineDefinition(false); 913 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 914 // Mark all preceding definitions as not being C99 inline definitions. 915 for (const FunctionDecl *Prev = Old; Prev; 916 Prev = Prev->getPreviousDeclaration()) 917 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 918 } 919 920 // Merge "pure" flag. 921 if (Old->isPure()) 922 New->setPure(); 923 924 // Merge the "deleted" flag. 925 if (Old->isDeleted()) 926 New->setDeleted(); 927 928 if (getLangOptions().CPlusPlus) 929 return MergeCXXFunctionDecl(New, Old); 930 931 return false; 932} 933 934/// MergeVarDecl - We just parsed a variable 'New' which has the same name 935/// and scope as a previous declaration 'Old'. Figure out how to resolve this 936/// situation, merging decls or emitting diagnostics as appropriate. 937/// 938/// Tentative definition rules (C99 6.9.2p2) are checked by 939/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 940/// definitions here, since the initializer hasn't been attached. 941/// 942void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 943 // If either decl is invalid, make sure the new one is marked invalid and 944 // don't do any other checking. 945 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 946 return New->setInvalidDecl(); 947 948 // Verify the old decl was also a variable. 949 VarDecl *Old = dyn_cast<VarDecl>(OldD); 950 if (!Old) { 951 Diag(New->getLocation(), diag::err_redefinition_different_kind) 952 << New->getDeclName(); 953 Diag(OldD->getLocation(), diag::note_previous_definition); 954 return New->setInvalidDecl(); 955 } 956 957 MergeAttributes(New, Old, Context); 958 959 // Merge the types 960 QualType MergedT; 961 if (getLangOptions().CPlusPlus) { 962 if (Context.hasSameType(New->getType(), Old->getType())) 963 MergedT = New->getType(); 964 } else { 965 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 966 } 967 if (MergedT.isNull()) { 968 Diag(New->getLocation(), diag::err_redefinition_different_type) 969 << New->getDeclName(); 970 Diag(Old->getLocation(), diag::note_previous_definition); 971 return New->setInvalidDecl(); 972 } 973 New->setType(MergedT); 974 975 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 976 if (New->getStorageClass() == VarDecl::Static && 977 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 978 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 979 Diag(Old->getLocation(), diag::note_previous_definition); 980 return New->setInvalidDecl(); 981 } 982 // C99 6.2.2p4: 983 // For an identifier declared with the storage-class specifier 984 // extern in a scope in which a prior declaration of that 985 // identifier is visible,23) if the prior declaration specifies 986 // internal or external linkage, the linkage of the identifier at 987 // the later declaration is the same as the linkage specified at 988 // the prior declaration. If no prior declaration is visible, or 989 // if the prior declaration specifies no linkage, then the 990 // identifier has external linkage. 991 if (New->hasExternalStorage() && Old->hasLinkage()) 992 /* Okay */; 993 else if (New->getStorageClass() != VarDecl::Static && 994 Old->getStorageClass() == VarDecl::Static) { 995 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 996 Diag(Old->getLocation(), diag::note_previous_definition); 997 return New->setInvalidDecl(); 998 } 999 1000 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1001 1002 // FIXME: The test for external storage here seems wrong? We still 1003 // need to check for mismatches. 1004 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1005 // Don't complain about out-of-line definitions of static members. 1006 !(Old->getLexicalDeclContext()->isRecord() && 1007 !New->getLexicalDeclContext()->isRecord())) { 1008 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1009 Diag(Old->getLocation(), diag::note_previous_definition); 1010 return New->setInvalidDecl(); 1011 } 1012 1013 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1014 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1015 Diag(Old->getLocation(), diag::note_previous_definition); 1016 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1017 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1018 Diag(Old->getLocation(), diag::note_previous_definition); 1019 } 1020 1021 // Keep a chain of previous declarations. 1022 New->setPreviousDeclaration(Old); 1023} 1024 1025/// CheckFallThrough - Check that we don't fall off the end of a 1026/// Statement that should return a value. 1027/// 1028/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1029/// MaybeFallThrough iff we might or might not fall off the end and 1030/// NeverFallThrough iff we never fall off the end of the statement. We assume 1031/// that functions not marked noreturn will return. 1032Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1033 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1034 1035 // FIXME: They should never return 0, fix that, delete this code. 1036 if (cfg == 0) 1037 return NeverFallThrough; 1038 // The CFG leaves in dead things, and we don't want to dead code paths to 1039 // confuse us, so we mark all live things first. 1040 std::queue<CFGBlock*> workq; 1041 llvm::BitVector live(cfg->getNumBlockIDs()); 1042 // Prep work queue 1043 workq.push(&cfg->getEntry()); 1044 // Solve 1045 while (!workq.empty()) { 1046 CFGBlock *item = workq.front(); 1047 workq.pop(); 1048 live.set(item->getBlockID()); 1049 for (CFGBlock::succ_iterator I=item->succ_begin(), 1050 E=item->succ_end(); 1051 I != E; 1052 ++I) { 1053 if ((*I) && !live[(*I)->getBlockID()]) { 1054 live.set((*I)->getBlockID()); 1055 workq.push(*I); 1056 } 1057 } 1058 } 1059 1060 // Now we know what is live, we check the live precessors of the exit block 1061 // and look for fall through paths, being careful to ignore normal returns, 1062 // and exceptional paths. 1063 bool HasLiveReturn = false; 1064 bool HasFakeEdge = false; 1065 bool HasPlainEdge = false; 1066 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1067 E = cfg->getExit().pred_end(); 1068 I != E; 1069 ++I) { 1070 CFGBlock& B = **I; 1071 if (!live[B.getBlockID()]) 1072 continue; 1073 if (B.size() == 0) { 1074 // A labeled empty statement, or the entry block... 1075 HasPlainEdge = true; 1076 continue; 1077 } 1078 Stmt *S = B[B.size()-1]; 1079 if (isa<ReturnStmt>(S)) { 1080 HasLiveReturn = true; 1081 continue; 1082 } 1083 if (isa<ObjCAtThrowStmt>(S)) { 1084 HasFakeEdge = true; 1085 continue; 1086 } 1087 if (isa<CXXThrowExpr>(S)) { 1088 HasFakeEdge = true; 1089 continue; 1090 } 1091 bool NoReturnEdge = false; 1092 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1093 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1094 if (CEE->getType().getNoReturnAttr()) { 1095 NoReturnEdge = true; 1096 HasFakeEdge = true; 1097 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1098 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1099 if (FD->hasAttr<NoReturnAttr>()) { 1100 NoReturnEdge = true; 1101 HasFakeEdge = true; 1102 } 1103 } 1104 } 1105 } 1106 // FIXME: Add noreturn message sends. 1107 if (NoReturnEdge == false) 1108 HasPlainEdge = true; 1109 } 1110 if (!HasPlainEdge) 1111 return NeverFallThrough; 1112 if (HasFakeEdge || HasLiveReturn) 1113 return MaybeFallThrough; 1114 // This says AlwaysFallThrough for calls to functions that are not marked 1115 // noreturn, that don't return. If people would like this warning to be more 1116 // accurate, such functions should be marked as noreturn. 1117 return AlwaysFallThrough; 1118} 1119 1120/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1121/// function that should return a value. Check that we don't fall off the end 1122/// of a noreturn function. We assume that functions and blocks not marked 1123/// noreturn will return. 1124void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1125 // FIXME: Would be nice if we had a better way to control cascading errors, 1126 // but for now, avoid them. The problem is that when Parse sees: 1127 // int foo() { return a; } 1128 // The return is eaten and the Sema code sees just: 1129 // int foo() { } 1130 // which this code would then warn about. 1131 if (getDiagnostics().hasErrorOccurred()) 1132 return; 1133 bool ReturnsVoid = false; 1134 bool HasNoReturn = false; 1135 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1136 if (FD->getResultType()->isVoidType()) 1137 ReturnsVoid = true; 1138 if (FD->hasAttr<NoReturnAttr>()) 1139 HasNoReturn = true; 1140 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1141 if (MD->getResultType()->isVoidType()) 1142 ReturnsVoid = true; 1143 if (MD->hasAttr<NoReturnAttr>()) 1144 HasNoReturn = true; 1145 } 1146 1147 // Short circuit for compilation speed. 1148 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1149 == Diagnostic::Ignored || ReturnsVoid) 1150 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1151 == Diagnostic::Ignored || !HasNoReturn) 1152 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1153 == Diagnostic::Ignored || !ReturnsVoid)) 1154 return; 1155 // FIXME: Funtion try block 1156 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1157 switch (CheckFallThrough(Body)) { 1158 case MaybeFallThrough: 1159 if (HasNoReturn) 1160 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1161 else if (!ReturnsVoid) 1162 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1163 break; 1164 case AlwaysFallThrough: 1165 if (HasNoReturn) 1166 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1167 else if (!ReturnsVoid) 1168 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1169 break; 1170 case NeverFallThrough: 1171 if (ReturnsVoid) 1172 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1173 break; 1174 } 1175 } 1176} 1177 1178/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1179/// that should return a value. Check that we don't fall off the end of a 1180/// noreturn block. We assume that functions and blocks not marked noreturn 1181/// will return. 1182void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1183 // FIXME: Would be nice if we had a better way to control cascading errors, 1184 // but for now, avoid them. The problem is that when Parse sees: 1185 // int foo() { return a; } 1186 // The return is eaten and the Sema code sees just: 1187 // int foo() { } 1188 // which this code would then warn about. 1189 if (getDiagnostics().hasErrorOccurred()) 1190 return; 1191 bool ReturnsVoid = false; 1192 bool HasNoReturn = false; 1193 if (const FunctionType *FT = BlockTy->getPointeeType()->getAsFunctionType()) { 1194 if (FT->getResultType()->isVoidType()) 1195 ReturnsVoid = true; 1196 if (FT->getNoReturnAttr()) 1197 HasNoReturn = true; 1198 } 1199 1200 // Short circuit for compilation speed. 1201 if (ReturnsVoid 1202 && !HasNoReturn 1203 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1204 == Diagnostic::Ignored || !ReturnsVoid)) 1205 return; 1206 // FIXME: Funtion try block 1207 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1208 switch (CheckFallThrough(Body)) { 1209 case MaybeFallThrough: 1210 if (HasNoReturn) 1211 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1212 else if (!ReturnsVoid) 1213 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1214 break; 1215 case AlwaysFallThrough: 1216 if (HasNoReturn) 1217 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1218 else if (!ReturnsVoid) 1219 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1220 break; 1221 case NeverFallThrough: 1222 if (ReturnsVoid) 1223 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1224 break; 1225 } 1226 } 1227} 1228 1229/// CheckParmsForFunctionDef - Check that the parameters of the given 1230/// function are appropriate for the definition of a function. This 1231/// takes care of any checks that cannot be performed on the 1232/// declaration itself, e.g., that the types of each of the function 1233/// parameters are complete. 1234bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1235 bool HasInvalidParm = false; 1236 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1237 ParmVarDecl *Param = FD->getParamDecl(p); 1238 1239 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1240 // function declarator that is part of a function definition of 1241 // that function shall not have incomplete type. 1242 // 1243 // This is also C++ [dcl.fct]p6. 1244 if (!Param->isInvalidDecl() && 1245 RequireCompleteType(Param->getLocation(), Param->getType(), 1246 diag::err_typecheck_decl_incomplete_type)) { 1247 Param->setInvalidDecl(); 1248 HasInvalidParm = true; 1249 } 1250 1251 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1252 // declaration of each parameter shall include an identifier. 1253 if (Param->getIdentifier() == 0 && 1254 !Param->isImplicit() && 1255 !getLangOptions().CPlusPlus) 1256 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1257 } 1258 1259 return HasInvalidParm; 1260} 1261 1262/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1263/// no declarator (e.g. "struct foo;") is parsed. 1264Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1265 // FIXME: Error on auto/register at file scope 1266 // FIXME: Error on inline/virtual/explicit 1267 // FIXME: Error on invalid restrict 1268 // FIXME: Warn on useless __thread 1269 // FIXME: Warn on useless const/volatile 1270 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1271 // FIXME: Warn on useless attributes 1272 TagDecl *Tag = 0; 1273 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1274 DS.getTypeSpecType() == DeclSpec::TST_struct || 1275 DS.getTypeSpecType() == DeclSpec::TST_union || 1276 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1277 if (!DS.getTypeRep()) // We probably had an error 1278 return DeclPtrTy(); 1279 1280 // Note that the above type specs guarantee that the 1281 // type rep is a Decl, whereas in many of the others 1282 // it's a Type. 1283 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1284 } 1285 1286 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1287 if (!Record->getDeclName() && Record->isDefinition() && 1288 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1289 if (getLangOptions().CPlusPlus || 1290 Record->getDeclContext()->isRecord()) 1291 return BuildAnonymousStructOrUnion(S, DS, Record); 1292 1293 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1294 << DS.getSourceRange(); 1295 } 1296 1297 // Microsoft allows unnamed struct/union fields. Don't complain 1298 // about them. 1299 // FIXME: Should we support Microsoft's extensions in this area? 1300 if (Record->getDeclName() && getLangOptions().Microsoft) 1301 return DeclPtrTy::make(Tag); 1302 } 1303 1304 if (!DS.isMissingDeclaratorOk() && 1305 DS.getTypeSpecType() != DeclSpec::TST_error) { 1306 // Warn about typedefs of enums without names, since this is an 1307 // extension in both Microsoft an GNU. 1308 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1309 Tag && isa<EnumDecl>(Tag)) { 1310 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1311 << DS.getSourceRange(); 1312 return DeclPtrTy::make(Tag); 1313 } 1314 1315 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1316 << DS.getSourceRange(); 1317 return DeclPtrTy(); 1318 } 1319 1320 return DeclPtrTy::make(Tag); 1321} 1322 1323/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1324/// anonymous struct or union AnonRecord into the owning context Owner 1325/// and scope S. This routine will be invoked just after we realize 1326/// that an unnamed union or struct is actually an anonymous union or 1327/// struct, e.g., 1328/// 1329/// @code 1330/// union { 1331/// int i; 1332/// float f; 1333/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1334/// // f into the surrounding scope.x 1335/// @endcode 1336/// 1337/// This routine is recursive, injecting the names of nested anonymous 1338/// structs/unions into the owning context and scope as well. 1339bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1340 RecordDecl *AnonRecord) { 1341 bool Invalid = false; 1342 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1343 FEnd = AnonRecord->field_end(); 1344 F != FEnd; ++F) { 1345 if ((*F)->getDeclName()) { 1346 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1347 LookupOrdinaryName, true); 1348 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1349 // C++ [class.union]p2: 1350 // The names of the members of an anonymous union shall be 1351 // distinct from the names of any other entity in the 1352 // scope in which the anonymous union is declared. 1353 unsigned diagKind 1354 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1355 : diag::err_anonymous_struct_member_redecl; 1356 Diag((*F)->getLocation(), diagKind) 1357 << (*F)->getDeclName(); 1358 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1359 Invalid = true; 1360 } else { 1361 // C++ [class.union]p2: 1362 // For the purpose of name lookup, after the anonymous union 1363 // definition, the members of the anonymous union are 1364 // considered to have been defined in the scope in which the 1365 // anonymous union is declared. 1366 Owner->makeDeclVisibleInContext(*F); 1367 S->AddDecl(DeclPtrTy::make(*F)); 1368 IdResolver.AddDecl(*F); 1369 } 1370 } else if (const RecordType *InnerRecordType 1371 = (*F)->getType()->getAs<RecordType>()) { 1372 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1373 if (InnerRecord->isAnonymousStructOrUnion()) 1374 Invalid = Invalid || 1375 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1376 } 1377 } 1378 1379 return Invalid; 1380} 1381 1382/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1383/// anonymous structure or union. Anonymous unions are a C++ feature 1384/// (C++ [class.union]) and a GNU C extension; anonymous structures 1385/// are a GNU C and GNU C++ extension. 1386Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1387 RecordDecl *Record) { 1388 DeclContext *Owner = Record->getDeclContext(); 1389 1390 // Diagnose whether this anonymous struct/union is an extension. 1391 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1392 Diag(Record->getLocation(), diag::ext_anonymous_union); 1393 else if (!Record->isUnion()) 1394 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1395 1396 // C and C++ require different kinds of checks for anonymous 1397 // structs/unions. 1398 bool Invalid = false; 1399 if (getLangOptions().CPlusPlus) { 1400 const char* PrevSpec = 0; 1401 unsigned DiagID; 1402 // C++ [class.union]p3: 1403 // Anonymous unions declared in a named namespace or in the 1404 // global namespace shall be declared static. 1405 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1406 (isa<TranslationUnitDecl>(Owner) || 1407 (isa<NamespaceDecl>(Owner) && 1408 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1409 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1410 Invalid = true; 1411 1412 // Recover by adding 'static'. 1413 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1414 PrevSpec, DiagID); 1415 } 1416 // C++ [class.union]p3: 1417 // A storage class is not allowed in a declaration of an 1418 // anonymous union in a class scope. 1419 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1420 isa<RecordDecl>(Owner)) { 1421 Diag(DS.getStorageClassSpecLoc(), 1422 diag::err_anonymous_union_with_storage_spec); 1423 Invalid = true; 1424 1425 // Recover by removing the storage specifier. 1426 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1427 PrevSpec, DiagID); 1428 } 1429 1430 // C++ [class.union]p2: 1431 // The member-specification of an anonymous union shall only 1432 // define non-static data members. [Note: nested types and 1433 // functions cannot be declared within an anonymous union. ] 1434 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1435 MemEnd = Record->decls_end(); 1436 Mem != MemEnd; ++Mem) { 1437 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1438 // C++ [class.union]p3: 1439 // An anonymous union shall not have private or protected 1440 // members (clause 11). 1441 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1442 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1443 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1444 Invalid = true; 1445 } 1446 } else if ((*Mem)->isImplicit()) { 1447 // Any implicit members are fine. 1448 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1449 // This is a type that showed up in an 1450 // elaborated-type-specifier inside the anonymous struct or 1451 // union, but which actually declares a type outside of the 1452 // anonymous struct or union. It's okay. 1453 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1454 if (!MemRecord->isAnonymousStructOrUnion() && 1455 MemRecord->getDeclName()) { 1456 // This is a nested type declaration. 1457 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1458 << (int)Record->isUnion(); 1459 Invalid = true; 1460 } 1461 } else { 1462 // We have something that isn't a non-static data 1463 // member. Complain about it. 1464 unsigned DK = diag::err_anonymous_record_bad_member; 1465 if (isa<TypeDecl>(*Mem)) 1466 DK = diag::err_anonymous_record_with_type; 1467 else if (isa<FunctionDecl>(*Mem)) 1468 DK = diag::err_anonymous_record_with_function; 1469 else if (isa<VarDecl>(*Mem)) 1470 DK = diag::err_anonymous_record_with_static; 1471 Diag((*Mem)->getLocation(), DK) 1472 << (int)Record->isUnion(); 1473 Invalid = true; 1474 } 1475 } 1476 } 1477 1478 if (!Record->isUnion() && !Owner->isRecord()) { 1479 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1480 << (int)getLangOptions().CPlusPlus; 1481 Invalid = true; 1482 } 1483 1484 // Create a declaration for this anonymous struct/union. 1485 NamedDecl *Anon = 0; 1486 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1487 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1488 /*IdentifierInfo=*/0, 1489 Context.getTypeDeclType(Record), 1490 /*BitWidth=*/0, /*Mutable=*/false, 1491 DS.getSourceRange().getBegin()); 1492 Anon->setAccess(AS_public); 1493 if (getLangOptions().CPlusPlus) 1494 FieldCollector->Add(cast<FieldDecl>(Anon)); 1495 } else { 1496 VarDecl::StorageClass SC; 1497 switch (DS.getStorageClassSpec()) { 1498 default: assert(0 && "Unknown storage class!"); 1499 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1500 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1501 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1502 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1503 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1504 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1505 case DeclSpec::SCS_mutable: 1506 // mutable can only appear on non-static class members, so it's always 1507 // an error here 1508 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1509 Invalid = true; 1510 SC = VarDecl::None; 1511 break; 1512 } 1513 1514 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1515 /*IdentifierInfo=*/0, 1516 Context.getTypeDeclType(Record), 1517 SC, DS.getSourceRange().getBegin()); 1518 } 1519 Anon->setImplicit(); 1520 1521 // Add the anonymous struct/union object to the current 1522 // context. We'll be referencing this object when we refer to one of 1523 // its members. 1524 Owner->addDecl(Anon); 1525 1526 // Inject the members of the anonymous struct/union into the owning 1527 // context and into the identifier resolver chain for name lookup 1528 // purposes. 1529 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1530 Invalid = true; 1531 1532 // Mark this as an anonymous struct/union type. Note that we do not 1533 // do this until after we have already checked and injected the 1534 // members of this anonymous struct/union type, because otherwise 1535 // the members could be injected twice: once by DeclContext when it 1536 // builds its lookup table, and once by 1537 // InjectAnonymousStructOrUnionMembers. 1538 Record->setAnonymousStructOrUnion(true); 1539 1540 if (Invalid) 1541 Anon->setInvalidDecl(); 1542 1543 return DeclPtrTy::make(Anon); 1544} 1545 1546 1547/// GetNameForDeclarator - Determine the full declaration name for the 1548/// given Declarator. 1549DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1550 switch (D.getKind()) { 1551 case Declarator::DK_Abstract: 1552 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1553 return DeclarationName(); 1554 1555 case Declarator::DK_Normal: 1556 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1557 return DeclarationName(D.getIdentifier()); 1558 1559 case Declarator::DK_Constructor: { 1560 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1561 return Context.DeclarationNames.getCXXConstructorName( 1562 Context.getCanonicalType(Ty)); 1563 } 1564 1565 case Declarator::DK_Destructor: { 1566 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1567 return Context.DeclarationNames.getCXXDestructorName( 1568 Context.getCanonicalType(Ty)); 1569 } 1570 1571 case Declarator::DK_Conversion: { 1572 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1573 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1574 return Context.DeclarationNames.getCXXConversionFunctionName( 1575 Context.getCanonicalType(Ty)); 1576 } 1577 1578 case Declarator::DK_Operator: 1579 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1580 return Context.DeclarationNames.getCXXOperatorName( 1581 D.getOverloadedOperator()); 1582 } 1583 1584 assert(false && "Unknown name kind"); 1585 return DeclarationName(); 1586} 1587 1588/// isNearlyMatchingFunction - Determine whether the C++ functions 1589/// Declaration and Definition are "nearly" matching. This heuristic 1590/// is used to improve diagnostics in the case where an out-of-line 1591/// function definition doesn't match any declaration within 1592/// the class or namespace. 1593static bool isNearlyMatchingFunction(ASTContext &Context, 1594 FunctionDecl *Declaration, 1595 FunctionDecl *Definition) { 1596 if (Declaration->param_size() != Definition->param_size()) 1597 return false; 1598 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1599 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1600 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1601 1602 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1603 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1604 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1605 return false; 1606 } 1607 1608 return true; 1609} 1610 1611Sema::DeclPtrTy 1612Sema::HandleDeclarator(Scope *S, Declarator &D, 1613 MultiTemplateParamsArg TemplateParamLists, 1614 bool IsFunctionDefinition) { 1615 DeclarationName Name = GetNameForDeclarator(D); 1616 1617 // All of these full declarators require an identifier. If it doesn't have 1618 // one, the ParsedFreeStandingDeclSpec action should be used. 1619 if (!Name) { 1620 if (!D.isInvalidType()) // Reject this if we think it is valid. 1621 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1622 diag::err_declarator_need_ident) 1623 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1624 return DeclPtrTy(); 1625 } 1626 1627 // The scope passed in may not be a decl scope. Zip up the scope tree until 1628 // we find one that is. 1629 while ((S->getFlags() & Scope::DeclScope) == 0 || 1630 (S->getFlags() & Scope::TemplateParamScope) != 0) 1631 S = S->getParent(); 1632 1633 // If this is an out-of-line definition of a member of a class template 1634 // or class template partial specialization, we may need to rebuild the 1635 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1636 // for more information. 1637 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1638 // handle expressions properly. 1639 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1640 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1641 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1642 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1643 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1644 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1645 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1646 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1647 QualType T = QualType::getFromOpaquePtr(DS.getTypeRep()); 1648 EnterDeclaratorContext(S, DC); 1649 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1650 ExitDeclaratorContext(S); 1651 if (T.isNull()) 1652 return DeclPtrTy(); 1653 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1654 } 1655 } 1656 1657 DeclContext *DC; 1658 NamedDecl *PrevDecl; 1659 NamedDecl *New; 1660 1661 QualType R = GetTypeForDeclarator(D, S); 1662 1663 // See if this is a redefinition of a variable in the same scope. 1664 if (D.getCXXScopeSpec().isInvalid()) { 1665 DC = CurContext; 1666 PrevDecl = 0; 1667 D.setInvalidType(); 1668 } else if (!D.getCXXScopeSpec().isSet()) { 1669 LookupNameKind NameKind = LookupOrdinaryName; 1670 1671 // If the declaration we're planning to build will be a function 1672 // or object with linkage, then look for another declaration with 1673 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1674 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1675 /* Do nothing*/; 1676 else if (R->isFunctionType()) { 1677 if (CurContext->isFunctionOrMethod() || 1678 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1679 NameKind = LookupRedeclarationWithLinkage; 1680 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1681 NameKind = LookupRedeclarationWithLinkage; 1682 else if (CurContext->getLookupContext()->isTranslationUnit() && 1683 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1684 NameKind = LookupRedeclarationWithLinkage; 1685 1686 DC = CurContext; 1687 PrevDecl = LookupName(S, Name, NameKind, true, 1688 NameKind == LookupRedeclarationWithLinkage, 1689 D.getIdentifierLoc()); 1690 } else { // Something like "int foo::x;" 1691 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1692 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1693 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1694 1695 // C++ 7.3.1.2p2: 1696 // Members (including explicit specializations of templates) of a named 1697 // namespace can also be defined outside that namespace by explicit 1698 // qualification of the name being defined, provided that the entity being 1699 // defined was already declared in the namespace and the definition appears 1700 // after the point of declaration in a namespace that encloses the 1701 // declarations namespace. 1702 // 1703 // Note that we only check the context at this point. We don't yet 1704 // have enough information to make sure that PrevDecl is actually 1705 // the declaration we want to match. For example, given: 1706 // 1707 // class X { 1708 // void f(); 1709 // void f(float); 1710 // }; 1711 // 1712 // void X::f(int) { } // ill-formed 1713 // 1714 // In this case, PrevDecl will point to the overload set 1715 // containing the two f's declared in X, but neither of them 1716 // matches. 1717 1718 // First check whether we named the global scope. 1719 if (isa<TranslationUnitDecl>(DC)) { 1720 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1721 << Name << D.getCXXScopeSpec().getRange(); 1722 } else if (!CurContext->Encloses(DC)) { 1723 // The qualifying scope doesn't enclose the original declaration. 1724 // Emit diagnostic based on current scope. 1725 SourceLocation L = D.getIdentifierLoc(); 1726 SourceRange R = D.getCXXScopeSpec().getRange(); 1727 if (isa<FunctionDecl>(CurContext)) 1728 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1729 else 1730 Diag(L, diag::err_invalid_declarator_scope) 1731 << Name << cast<NamedDecl>(DC) << R; 1732 D.setInvalidType(); 1733 } 1734 } 1735 1736 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1737 // Maybe we will complain about the shadowed template parameter. 1738 if (!D.isInvalidType()) 1739 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1740 D.setInvalidType(); 1741 1742 // Just pretend that we didn't see the previous declaration. 1743 PrevDecl = 0; 1744 } 1745 1746 // In C++, the previous declaration we find might be a tag type 1747 // (class or enum). In this case, the new declaration will hide the 1748 // tag type. Note that this does does not apply if we're declaring a 1749 // typedef (C++ [dcl.typedef]p4). 1750 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1751 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1752 PrevDecl = 0; 1753 1754 bool Redeclaration = false; 1755 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1756 if (TemplateParamLists.size()) { 1757 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1758 return DeclPtrTy(); 1759 } 1760 1761 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1762 } else if (R->isFunctionType()) { 1763 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1764 move(TemplateParamLists), 1765 IsFunctionDefinition, Redeclaration); 1766 } else { 1767 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1768 move(TemplateParamLists), 1769 Redeclaration); 1770 } 1771 1772 if (New == 0) 1773 return DeclPtrTy(); 1774 1775 // If this has an identifier and is not an invalid redeclaration, 1776 // add it to the scope stack. 1777 if (Name && !(Redeclaration && New->isInvalidDecl())) 1778 PushOnScopeChains(New, S); 1779 1780 return DeclPtrTy::make(New); 1781} 1782 1783/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1784/// types into constant array types in certain situations which would otherwise 1785/// be errors (for GCC compatibility). 1786static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1787 ASTContext &Context, 1788 bool &SizeIsNegative) { 1789 // This method tries to turn a variable array into a constant 1790 // array even when the size isn't an ICE. This is necessary 1791 // for compatibility with code that depends on gcc's buggy 1792 // constant expression folding, like struct {char x[(int)(char*)2];} 1793 SizeIsNegative = false; 1794 1795 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1796 QualType Pointee = PTy->getPointeeType(); 1797 QualType FixedType = 1798 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1799 if (FixedType.isNull()) return FixedType; 1800 FixedType = Context.getPointerType(FixedType); 1801 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1802 return FixedType; 1803 } 1804 1805 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1806 if (!VLATy) 1807 return QualType(); 1808 // FIXME: We should probably handle this case 1809 if (VLATy->getElementType()->isVariablyModifiedType()) 1810 return QualType(); 1811 1812 Expr::EvalResult EvalResult; 1813 if (!VLATy->getSizeExpr() || 1814 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1815 !EvalResult.Val.isInt()) 1816 return QualType(); 1817 1818 llvm::APSInt &Res = EvalResult.Val.getInt(); 1819 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1820 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1821 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1822 // so as to transfer ownership to the ConstantArrayWithExpr. 1823 // Alternatively, we could "clone" it (how?). 1824 // Since we don't know how to do things above, we just use the 1825 // very same Expr*. 1826 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1827 Res, ArySizeExpr, 1828 ArrayType::Normal, 0, 1829 VLATy->getBracketsRange()); 1830 } 1831 1832 SizeIsNegative = true; 1833 return QualType(); 1834} 1835 1836/// \brief Register the given locally-scoped external C declaration so 1837/// that it can be found later for redeclarations 1838void 1839Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1840 Scope *S) { 1841 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1842 "Decl is not a locally-scoped decl!"); 1843 // Note that we have a locally-scoped external with this name. 1844 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1845 1846 if (!PrevDecl) 1847 return; 1848 1849 // If there was a previous declaration of this variable, it may be 1850 // in our identifier chain. Update the identifier chain with the new 1851 // declaration. 1852 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1853 // The previous declaration was found on the identifer resolver 1854 // chain, so remove it from its scope. 1855 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1856 S = S->getParent(); 1857 1858 if (S) 1859 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1860 } 1861} 1862 1863/// \brief Diagnose function specifiers on a declaration of an identifier that 1864/// does not identify a function. 1865void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1866 // FIXME: We should probably indicate the identifier in question to avoid 1867 // confusion for constructs like "inline int a(), b;" 1868 if (D.getDeclSpec().isInlineSpecified()) 1869 Diag(D.getDeclSpec().getInlineSpecLoc(), 1870 diag::err_inline_non_function); 1871 1872 if (D.getDeclSpec().isVirtualSpecified()) 1873 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1874 diag::err_virtual_non_function); 1875 1876 if (D.getDeclSpec().isExplicitSpecified()) 1877 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1878 diag::err_explicit_non_function); 1879} 1880 1881NamedDecl* 1882Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1883 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1884 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1885 if (D.getCXXScopeSpec().isSet()) { 1886 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1887 << D.getCXXScopeSpec().getRange(); 1888 D.setInvalidType(); 1889 // Pretend we didn't see the scope specifier. 1890 DC = 0; 1891 } 1892 1893 if (getLangOptions().CPlusPlus) { 1894 // Check that there are no default arguments (C++ only). 1895 CheckExtraCXXDefaultArguments(D); 1896 } 1897 1898 DiagnoseFunctionSpecifiers(D); 1899 1900 if (D.getDeclSpec().isThreadSpecified()) 1901 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1902 1903 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1904 if (!NewTD) return 0; 1905 1906 if (D.isInvalidType()) 1907 NewTD->setInvalidDecl(); 1908 1909 // Handle attributes prior to checking for duplicates in MergeVarDecl 1910 ProcessDeclAttributes(S, NewTD, D); 1911 // Merge the decl with the existing one if appropriate. If the decl is 1912 // in an outer scope, it isn't the same thing. 1913 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1914 Redeclaration = true; 1915 MergeTypeDefDecl(NewTD, PrevDecl); 1916 } 1917 1918 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1919 // then it shall have block scope. 1920 QualType T = NewTD->getUnderlyingType(); 1921 if (T->isVariablyModifiedType()) { 1922 CurFunctionNeedsScopeChecking = true; 1923 1924 if (S->getFnParent() == 0) { 1925 bool SizeIsNegative; 1926 QualType FixedTy = 1927 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1928 if (!FixedTy.isNull()) { 1929 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1930 NewTD->setUnderlyingType(FixedTy); 1931 } else { 1932 if (SizeIsNegative) 1933 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1934 else if (T->isVariableArrayType()) 1935 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1936 else 1937 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1938 NewTD->setInvalidDecl(); 1939 } 1940 } 1941 } 1942 1943 // If this is the C FILE type, notify the AST context. 1944 if (IdentifierInfo *II = NewTD->getIdentifier()) 1945 if (!NewTD->isInvalidDecl() && 1946 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1947 if (II->isStr("FILE")) 1948 Context.setFILEDecl(NewTD); 1949 else if (II->isStr("jmp_buf")) 1950 Context.setjmp_bufDecl(NewTD); 1951 else if (II->isStr("sigjmp_buf")) 1952 Context.setsigjmp_bufDecl(NewTD); 1953 } 1954 1955 return NewTD; 1956} 1957 1958/// \brief Determines whether the given declaration is an out-of-scope 1959/// previous declaration. 1960/// 1961/// This routine should be invoked when name lookup has found a 1962/// previous declaration (PrevDecl) that is not in the scope where a 1963/// new declaration by the same name is being introduced. If the new 1964/// declaration occurs in a local scope, previous declarations with 1965/// linkage may still be considered previous declarations (C99 1966/// 6.2.2p4-5, C++ [basic.link]p6). 1967/// 1968/// \param PrevDecl the previous declaration found by name 1969/// lookup 1970/// 1971/// \param DC the context in which the new declaration is being 1972/// declared. 1973/// 1974/// \returns true if PrevDecl is an out-of-scope previous declaration 1975/// for a new delcaration with the same name. 1976static bool 1977isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1978 ASTContext &Context) { 1979 if (!PrevDecl) 1980 return 0; 1981 1982 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1983 // case we need to check each of the overloaded functions. 1984 if (!PrevDecl->hasLinkage()) 1985 return false; 1986 1987 if (Context.getLangOptions().CPlusPlus) { 1988 // C++ [basic.link]p6: 1989 // If there is a visible declaration of an entity with linkage 1990 // having the same name and type, ignoring entities declared 1991 // outside the innermost enclosing namespace scope, the block 1992 // scope declaration declares that same entity and receives the 1993 // linkage of the previous declaration. 1994 DeclContext *OuterContext = DC->getLookupContext(); 1995 if (!OuterContext->isFunctionOrMethod()) 1996 // This rule only applies to block-scope declarations. 1997 return false; 1998 else { 1999 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2000 if (PrevOuterContext->isRecord()) 2001 // We found a member function: ignore it. 2002 return false; 2003 else { 2004 // Find the innermost enclosing namespace for the new and 2005 // previous declarations. 2006 while (!OuterContext->isFileContext()) 2007 OuterContext = OuterContext->getParent(); 2008 while (!PrevOuterContext->isFileContext()) 2009 PrevOuterContext = PrevOuterContext->getParent(); 2010 2011 // The previous declaration is in a different namespace, so it 2012 // isn't the same function. 2013 if (OuterContext->getPrimaryContext() != 2014 PrevOuterContext->getPrimaryContext()) 2015 return false; 2016 } 2017 } 2018 } 2019 2020 return true; 2021} 2022 2023NamedDecl* 2024Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2025 QualType R,NamedDecl* PrevDecl, 2026 MultiTemplateParamsArg TemplateParamLists, 2027 bool &Redeclaration) { 2028 DeclarationName Name = GetNameForDeclarator(D); 2029 2030 // Check that there are no default arguments (C++ only). 2031 if (getLangOptions().CPlusPlus) 2032 CheckExtraCXXDefaultArguments(D); 2033 2034 VarDecl *NewVD; 2035 VarDecl::StorageClass SC; 2036 switch (D.getDeclSpec().getStorageClassSpec()) { 2037 default: assert(0 && "Unknown storage class!"); 2038 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2039 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2040 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2041 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2042 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2043 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2044 case DeclSpec::SCS_mutable: 2045 // mutable can only appear on non-static class members, so it's always 2046 // an error here 2047 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2048 D.setInvalidType(); 2049 SC = VarDecl::None; 2050 break; 2051 } 2052 2053 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2054 if (!II) { 2055 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2056 << Name.getAsString(); 2057 return 0; 2058 } 2059 2060 DiagnoseFunctionSpecifiers(D); 2061 2062 if (!DC->isRecord() && S->getFnParent() == 0) { 2063 // C99 6.9p2: The storage-class specifiers auto and register shall not 2064 // appear in the declaration specifiers in an external declaration. 2065 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2066 2067 // If this is a register variable with an asm label specified, then this 2068 // is a GNU extension. 2069 if (SC == VarDecl::Register && D.getAsmLabel()) 2070 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2071 else 2072 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2073 D.setInvalidType(); 2074 } 2075 } 2076 if (DC->isRecord() && !CurContext->isRecord()) { 2077 // This is an out-of-line definition of a static data member. 2078 if (SC == VarDecl::Static) { 2079 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2080 diag::err_static_out_of_line) 2081 << CodeModificationHint::CreateRemoval( 2082 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2083 } else if (SC == VarDecl::None) 2084 SC = VarDecl::Static; 2085 } 2086 if (SC == VarDecl::Static) { 2087 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2088 if (RD->isLocalClass()) 2089 Diag(D.getIdentifierLoc(), 2090 diag::err_static_data_member_not_allowed_in_local_class) 2091 << Name << RD->getDeclName(); 2092 } 2093 } 2094 2095 // Check that we can declare a template here. 2096 if (TemplateParamLists.size() && 2097 CheckTemplateDeclScope(S, TemplateParamLists)) 2098 return 0; 2099 2100 // Match up the template parameter lists with the scope specifier, then 2101 // determine whether we have a template or a template specialization. 2102 if (TemplateParameterList *TemplateParams 2103 = MatchTemplateParametersToScopeSpecifier( 2104 D.getDeclSpec().getSourceRange().getBegin(), 2105 D.getCXXScopeSpec(), 2106 (TemplateParameterList**)TemplateParamLists.get(), 2107 TemplateParamLists.size())) { 2108 if (TemplateParams->size() > 0) { 2109 // There is no such thing as a variable template. 2110 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2111 << II 2112 << SourceRange(TemplateParams->getTemplateLoc(), 2113 TemplateParams->getRAngleLoc()); 2114 return 0; 2115 } else { 2116 // There is an extraneous 'template<>' for this variable. Complain 2117 // about it, but allow the declaration of the variable. 2118 Diag(TemplateParams->getTemplateLoc(), 2119 diag::err_template_variable_noparams) 2120 << II 2121 << SourceRange(TemplateParams->getTemplateLoc(), 2122 TemplateParams->getRAngleLoc()); 2123 } 2124 } 2125 2126 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2127 II, R, SC, 2128 // FIXME: Move to DeclGroup... 2129 D.getDeclSpec().getSourceRange().getBegin()); 2130 2131 if (D.isInvalidType()) 2132 NewVD->setInvalidDecl(); 2133 2134 if (D.getDeclSpec().isThreadSpecified()) { 2135 if (NewVD->hasLocalStorage()) 2136 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2137 else if (!Context.Target.isTLSSupported()) 2138 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2139 else 2140 NewVD->setThreadSpecified(true); 2141 } 2142 2143 // Set the lexical context. If the declarator has a C++ scope specifier, the 2144 // lexical context will be different from the semantic context. 2145 NewVD->setLexicalDeclContext(CurContext); 2146 2147 // Handle attributes prior to checking for duplicates in MergeVarDecl 2148 ProcessDeclAttributes(S, NewVD, D); 2149 2150 // Handle GNU asm-label extension (encoded as an attribute). 2151 if (Expr *E = (Expr*) D.getAsmLabel()) { 2152 // The parser guarantees this is a string. 2153 StringLiteral *SE = cast<StringLiteral>(E); 2154 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2155 SE->getByteLength()))); 2156 } 2157 2158 // If name lookup finds a previous declaration that is not in the 2159 // same scope as the new declaration, this may still be an 2160 // acceptable redeclaration. 2161 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2162 !(NewVD->hasLinkage() && 2163 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2164 PrevDecl = 0; 2165 2166 // Merge the decl with the existing one if appropriate. 2167 if (PrevDecl) { 2168 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2169 // The user tried to define a non-static data member 2170 // out-of-line (C++ [dcl.meaning]p1). 2171 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2172 << D.getCXXScopeSpec().getRange(); 2173 PrevDecl = 0; 2174 NewVD->setInvalidDecl(); 2175 } 2176 } else if (D.getCXXScopeSpec().isSet()) { 2177 // No previous declaration in the qualifying scope. 2178 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 2179 << Name << D.getCXXScopeSpec().getRange(); 2180 NewVD->setInvalidDecl(); 2181 } 2182 2183 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2184 2185 // attributes declared post-definition are currently ignored 2186 if (PrevDecl) { 2187 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2188 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2189 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2190 Diag(Def->getLocation(), diag::note_previous_definition); 2191 } 2192 } 2193 2194 // If this is a locally-scoped extern C variable, update the map of 2195 // such variables. 2196 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 2197 !NewVD->isInvalidDecl()) 2198 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2199 2200 return NewVD; 2201} 2202 2203/// \brief Perform semantic checking on a newly-created variable 2204/// declaration. 2205/// 2206/// This routine performs all of the type-checking required for a 2207/// variable declaration once it has been built. It is used both to 2208/// check variables after they have been parsed and their declarators 2209/// have been translated into a declaration, and to check variables 2210/// that have been instantiated from a template. 2211/// 2212/// Sets NewVD->isInvalidDecl() if an error was encountered. 2213void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2214 bool &Redeclaration) { 2215 // If the decl is already known invalid, don't check it. 2216 if (NewVD->isInvalidDecl()) 2217 return; 2218 2219 QualType T = NewVD->getType(); 2220 2221 if (T->isObjCInterfaceType()) { 2222 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2223 return NewVD->setInvalidDecl(); 2224 } 2225 2226 // The variable can not have an abstract class type. 2227 if (RequireNonAbstractType(NewVD->getLocation(), T, 2228 diag::err_abstract_type_in_decl, 2229 AbstractVariableType)) 2230 return NewVD->setInvalidDecl(); 2231 2232 // Emit an error if an address space was applied to decl with local storage. 2233 // This includes arrays of objects with address space qualifiers, but not 2234 // automatic variables that point to other address spaces. 2235 // ISO/IEC TR 18037 S5.1.2 2236 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2237 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2238 return NewVD->setInvalidDecl(); 2239 } 2240 2241 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2242 && !NewVD->hasAttr<BlocksAttr>()) 2243 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2244 2245 bool isVM = T->isVariablyModifiedType(); 2246 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2247 NewVD->hasAttr<BlocksAttr>()) 2248 CurFunctionNeedsScopeChecking = true; 2249 2250 if ((isVM && NewVD->hasLinkage()) || 2251 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2252 bool SizeIsNegative; 2253 QualType FixedTy = 2254 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2255 2256 if (FixedTy.isNull() && T->isVariableArrayType()) { 2257 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2258 // FIXME: This won't give the correct result for 2259 // int a[10][n]; 2260 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2261 2262 if (NewVD->isFileVarDecl()) 2263 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2264 << SizeRange; 2265 else if (NewVD->getStorageClass() == VarDecl::Static) 2266 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2267 << SizeRange; 2268 else 2269 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2270 << SizeRange; 2271 return NewVD->setInvalidDecl(); 2272 } 2273 2274 if (FixedTy.isNull()) { 2275 if (NewVD->isFileVarDecl()) 2276 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2277 else 2278 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2279 return NewVD->setInvalidDecl(); 2280 } 2281 2282 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2283 NewVD->setType(FixedTy); 2284 } 2285 2286 if (!PrevDecl && NewVD->isExternC(Context)) { 2287 // Since we did not find anything by this name and we're declaring 2288 // an extern "C" variable, look for a non-visible extern "C" 2289 // declaration with the same name. 2290 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2291 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2292 if (Pos != LocallyScopedExternalDecls.end()) 2293 PrevDecl = Pos->second; 2294 } 2295 2296 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2297 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2298 << T; 2299 return NewVD->setInvalidDecl(); 2300 } 2301 2302 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2303 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2304 return NewVD->setInvalidDecl(); 2305 } 2306 2307 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2308 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2309 return NewVD->setInvalidDecl(); 2310 } 2311 2312 if (PrevDecl) { 2313 Redeclaration = true; 2314 MergeVarDecl(NewVD, PrevDecl); 2315 } 2316} 2317 2318NamedDecl* 2319Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2320 QualType R, NamedDecl* PrevDecl, 2321 MultiTemplateParamsArg TemplateParamLists, 2322 bool IsFunctionDefinition, bool &Redeclaration) { 2323 assert(R.getTypePtr()->isFunctionType()); 2324 2325 DeclarationName Name = GetNameForDeclarator(D); 2326 FunctionDecl::StorageClass SC = FunctionDecl::None; 2327 switch (D.getDeclSpec().getStorageClassSpec()) { 2328 default: assert(0 && "Unknown storage class!"); 2329 case DeclSpec::SCS_auto: 2330 case DeclSpec::SCS_register: 2331 case DeclSpec::SCS_mutable: 2332 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2333 diag::err_typecheck_sclass_func); 2334 D.setInvalidType(); 2335 break; 2336 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2337 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2338 case DeclSpec::SCS_static: { 2339 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2340 // C99 6.7.1p5: 2341 // The declaration of an identifier for a function that has 2342 // block scope shall have no explicit storage-class specifier 2343 // other than extern 2344 // See also (C++ [dcl.stc]p4). 2345 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2346 diag::err_static_block_func); 2347 SC = FunctionDecl::None; 2348 } else 2349 SC = FunctionDecl::Static; 2350 break; 2351 } 2352 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2353 } 2354 2355 if (D.getDeclSpec().isThreadSpecified()) 2356 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2357 2358 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2359 bool isInline = D.getDeclSpec().isInlineSpecified(); 2360 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2361 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2362 2363 // Check that the return type is not an abstract class type. 2364 // For record types, this is done by the AbstractClassUsageDiagnoser once 2365 // the class has been completely parsed. 2366 if (!DC->isRecord() && 2367 RequireNonAbstractType(D.getIdentifierLoc(), 2368 R->getAsFunctionType()->getResultType(), 2369 diag::err_abstract_type_in_decl, 2370 AbstractReturnType)) 2371 D.setInvalidType(); 2372 2373 // Do not allow returning a objc interface by-value. 2374 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2375 Diag(D.getIdentifierLoc(), 2376 diag::err_object_cannot_be_passed_returned_by_value) << 0 2377 << R->getAsFunctionType()->getResultType(); 2378 D.setInvalidType(); 2379 } 2380 2381 // Check that we can declare a template here. 2382 if (TemplateParamLists.size() && 2383 CheckTemplateDeclScope(S, TemplateParamLists)) 2384 return 0; 2385 2386 bool isVirtualOkay = false; 2387 FunctionDecl *NewFD; 2388 if (isFriend) { 2389 // DC is the namespace in which the function is being declared. 2390 assert(DC->isFileContext() || PrevDecl); 2391 2392 // C++ [class.friend]p5 2393 // A function can be defined in a friend declaration of a 2394 // class . . . . Such a function is implicitly inline. 2395 isInline |= IsFunctionDefinition; 2396 2397 NewFD = FriendFunctionDecl::Create(Context, DC, 2398 D.getIdentifierLoc(), Name, R, 2399 isInline, 2400 D.getDeclSpec().getFriendSpecLoc()); 2401 } else if (D.getKind() == Declarator::DK_Constructor) { 2402 // This is a C++ constructor declaration. 2403 assert(DC->isRecord() && 2404 "Constructors can only be declared in a member context"); 2405 2406 R = CheckConstructorDeclarator(D, R, SC); 2407 2408 // Create the new declaration 2409 NewFD = CXXConstructorDecl::Create(Context, 2410 cast<CXXRecordDecl>(DC), 2411 D.getIdentifierLoc(), Name, R, 2412 isExplicit, isInline, 2413 /*isImplicitlyDeclared=*/false); 2414 } else if (D.getKind() == Declarator::DK_Destructor) { 2415 // This is a C++ destructor declaration. 2416 if (DC->isRecord()) { 2417 R = CheckDestructorDeclarator(D, SC); 2418 2419 NewFD = CXXDestructorDecl::Create(Context, 2420 cast<CXXRecordDecl>(DC), 2421 D.getIdentifierLoc(), Name, R, 2422 isInline, 2423 /*isImplicitlyDeclared=*/false); 2424 2425 isVirtualOkay = true; 2426 } else { 2427 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2428 2429 // Create a FunctionDecl to satisfy the function definition parsing 2430 // code path. 2431 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2432 Name, R, SC, isInline, 2433 /*hasPrototype=*/true, 2434 // FIXME: Move to DeclGroup... 2435 D.getDeclSpec().getSourceRange().getBegin()); 2436 D.setInvalidType(); 2437 } 2438 } else if (D.getKind() == Declarator::DK_Conversion) { 2439 if (!DC->isRecord()) { 2440 Diag(D.getIdentifierLoc(), 2441 diag::err_conv_function_not_member); 2442 return 0; 2443 } 2444 2445 CheckConversionDeclarator(D, R, SC); 2446 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2447 D.getIdentifierLoc(), Name, R, 2448 isInline, isExplicit); 2449 2450 isVirtualOkay = true; 2451 } else if (DC->isRecord()) { 2452 // If the of the function is the same as the name of the record, then this 2453 // must be an invalid constructor that has a return type. 2454 // (The parser checks for a return type and makes the declarator a 2455 // constructor if it has no return type). 2456 // must have an invalid constructor that has a return type 2457 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2458 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2459 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2460 << SourceRange(D.getIdentifierLoc()); 2461 return 0; 2462 } 2463 2464 // This is a C++ method declaration. 2465 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2466 D.getIdentifierLoc(), Name, R, 2467 (SC == FunctionDecl::Static), isInline); 2468 2469 isVirtualOkay = (SC != FunctionDecl::Static); 2470 } else { 2471 // Determine whether the function was written with a 2472 // prototype. This true when: 2473 // - we're in C++ (where every function has a prototype), 2474 // - there is a prototype in the declarator, or 2475 // - the type R of the function is some kind of typedef or other reference 2476 // to a type name (which eventually refers to a function type). 2477 bool HasPrototype = 2478 getLangOptions().CPlusPlus || 2479 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2480 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2481 2482 NewFD = FunctionDecl::Create(Context, DC, 2483 D.getIdentifierLoc(), 2484 Name, R, SC, isInline, HasPrototype, 2485 // FIXME: Move to DeclGroup... 2486 D.getDeclSpec().getSourceRange().getBegin()); 2487 } 2488 2489 if (D.isInvalidType()) 2490 NewFD->setInvalidDecl(); 2491 2492 // Set the lexical context. If the declarator has a C++ 2493 // scope specifier, the lexical context will be different 2494 // from the semantic context. 2495 NewFD->setLexicalDeclContext(CurContext); 2496 2497 // Match up the template parameter lists with the scope specifier, then 2498 // determine whether we have a template or a template specialization. 2499 FunctionTemplateDecl *FunctionTemplate = 0; 2500 if (TemplateParameterList *TemplateParams 2501 = MatchTemplateParametersToScopeSpecifier( 2502 D.getDeclSpec().getSourceRange().getBegin(), 2503 D.getCXXScopeSpec(), 2504 (TemplateParameterList**)TemplateParamLists.get(), 2505 TemplateParamLists.size())) { 2506 if (TemplateParams->size() > 0) { 2507 // This is a function template 2508 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2509 NewFD->getLocation(), 2510 Name, TemplateParams, 2511 NewFD); 2512 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2513 } else { 2514 // FIXME: Handle function template specializations 2515 } 2516 2517 // FIXME: Free this memory properly. 2518 TemplateParamLists.release(); 2519 } 2520 2521 // C++ [dcl.fct.spec]p5: 2522 // The virtual specifier shall only be used in declarations of 2523 // nonstatic class member functions that appear within a 2524 // member-specification of a class declaration; see 10.3. 2525 // 2526 if (isVirtual && !NewFD->isInvalidDecl()) { 2527 if (!isVirtualOkay) { 2528 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2529 diag::err_virtual_non_function); 2530 } else if (!CurContext->isRecord()) { 2531 // 'virtual' was specified outside of the class. 2532 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2533 << CodeModificationHint::CreateRemoval( 2534 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2535 } else { 2536 // Okay: Add virtual to the method. 2537 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2538 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2539 CurClass->setAggregate(false); 2540 CurClass->setPOD(false); 2541 CurClass->setEmpty(false); 2542 CurClass->setPolymorphic(true); 2543 CurClass->setHasTrivialConstructor(false); 2544 CurClass->setHasTrivialCopyConstructor(false); 2545 CurClass->setHasTrivialCopyAssignment(false); 2546 } 2547 } 2548 2549 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2550 // Look for virtual methods in base classes that this method might override. 2551 2552 BasePaths Paths; 2553 if (LookupInBases(cast<CXXRecordDecl>(DC), 2554 MemberLookupCriteria(NewMD), Paths)) { 2555 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2556 E = Paths.found_decls_end(); I != E; ++I) { 2557 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2558 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2559 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2560 NewMD->addOverriddenMethod(OldMD); 2561 } 2562 } 2563 } 2564 } 2565 2566 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2567 !CurContext->isRecord()) { 2568 // C++ [class.static]p1: 2569 // A data or function member of a class may be declared static 2570 // in a class definition, in which case it is a static member of 2571 // the class. 2572 2573 // Complain about the 'static' specifier if it's on an out-of-line 2574 // member function definition. 2575 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2576 diag::err_static_out_of_line) 2577 << CodeModificationHint::CreateRemoval( 2578 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2579 } 2580 2581 // Handle GNU asm-label extension (encoded as an attribute). 2582 if (Expr *E = (Expr*) D.getAsmLabel()) { 2583 // The parser guarantees this is a string. 2584 StringLiteral *SE = cast<StringLiteral>(E); 2585 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2586 SE->getByteLength()))); 2587 } 2588 2589 // Copy the parameter declarations from the declarator D to the function 2590 // declaration NewFD, if they are available. First scavenge them into Params. 2591 llvm::SmallVector<ParmVarDecl*, 16> Params; 2592 if (D.getNumTypeObjects() > 0) { 2593 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2594 2595 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2596 // function that takes no arguments, not a function that takes a 2597 // single void argument. 2598 // We let through "const void" here because Sema::GetTypeForDeclarator 2599 // already checks for that case. 2600 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2601 FTI.ArgInfo[0].Param && 2602 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2603 // Empty arg list, don't push any params. 2604 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2605 2606 // In C++, the empty parameter-type-list must be spelled "void"; a 2607 // typedef of void is not permitted. 2608 if (getLangOptions().CPlusPlus && 2609 Param->getType().getUnqualifiedType() != Context.VoidTy) 2610 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2611 // FIXME: Leaks decl? 2612 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2613 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2614 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2615 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2616 Param->setDeclContext(NewFD); 2617 Params.push_back(Param); 2618 } 2619 } 2620 2621 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2622 // When we're declaring a function with a typedef, typeof, etc as in the 2623 // following example, we'll need to synthesize (unnamed) 2624 // parameters for use in the declaration. 2625 // 2626 // @code 2627 // typedef void fn(int); 2628 // fn f; 2629 // @endcode 2630 2631 // Synthesize a parameter for each argument type. 2632 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2633 AE = FT->arg_type_end(); AI != AE; ++AI) { 2634 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2635 SourceLocation(), 0, 2636 *AI, VarDecl::None, 0); 2637 Param->setImplicit(); 2638 Params.push_back(Param); 2639 } 2640 } else { 2641 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2642 "Should not need args for typedef of non-prototype fn"); 2643 } 2644 // Finally, we know we have the right number of parameters, install them. 2645 NewFD->setParams(Context, Params.data(), Params.size()); 2646 2647 // If name lookup finds a previous declaration that is not in the 2648 // same scope as the new declaration, this may still be an 2649 // acceptable redeclaration. 2650 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2651 !(NewFD->hasLinkage() && 2652 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2653 PrevDecl = 0; 2654 2655 // Perform semantic checking on the function declaration. 2656 bool OverloadableAttrRequired = false; // FIXME: HACK! 2657 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2658 /*FIXME:*/OverloadableAttrRequired); 2659 2660 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2661 // An out-of-line member function declaration must also be a 2662 // definition (C++ [dcl.meaning]p1). 2663 if (!IsFunctionDefinition && !isFriend) { 2664 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2665 << D.getCXXScopeSpec().getRange(); 2666 NewFD->setInvalidDecl(); 2667 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2668 // The user tried to provide an out-of-line definition for a 2669 // function that is a member of a class or namespace, but there 2670 // was no such member function declared (C++ [class.mfct]p2, 2671 // C++ [namespace.memdef]p2). For example: 2672 // 2673 // class X { 2674 // void f() const; 2675 // }; 2676 // 2677 // void X::f() { } // ill-formed 2678 // 2679 // Complain about this problem, and attempt to suggest close 2680 // matches (e.g., those that differ only in cv-qualifiers and 2681 // whether the parameter types are references). 2682 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2683 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2684 NewFD->setInvalidDecl(); 2685 2686 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2687 true); 2688 assert(!Prev.isAmbiguous() && 2689 "Cannot have an ambiguity in previous-declaration lookup"); 2690 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2691 Func != FuncEnd; ++Func) { 2692 if (isa<FunctionDecl>(*Func) && 2693 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2694 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2695 } 2696 2697 PrevDecl = 0; 2698 } 2699 } 2700 2701 // Handle attributes. We need to have merged decls when handling attributes 2702 // (for example to check for conflicts, etc). 2703 // FIXME: This needs to happen before we merge declarations. Then, 2704 // let attribute merging cope with attribute conflicts. 2705 ProcessDeclAttributes(S, NewFD, D); 2706 2707 // attributes declared post-definition are currently ignored 2708 if (PrevDecl) { 2709 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2710 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2711 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2712 Diag(Def->getLocation(), diag::note_previous_definition); 2713 } 2714 } 2715 2716 AddKnownFunctionAttributes(NewFD); 2717 2718 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2719 // If a function name is overloadable in C, then every function 2720 // with that name must be marked "overloadable". 2721 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2722 << Redeclaration << NewFD; 2723 if (PrevDecl) 2724 Diag(PrevDecl->getLocation(), 2725 diag::note_attribute_overloadable_prev_overload); 2726 NewFD->addAttr(::new (Context) OverloadableAttr()); 2727 } 2728 2729 // If this is a locally-scoped extern C function, update the 2730 // map of such names. 2731 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2732 && !NewFD->isInvalidDecl()) 2733 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2734 2735 // Set this FunctionDecl's range up to the right paren. 2736 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2737 2738 if (FunctionTemplate && NewFD->isInvalidDecl()) 2739 FunctionTemplate->setInvalidDecl(); 2740 2741 if (FunctionTemplate) 2742 return FunctionTemplate; 2743 2744 return NewFD; 2745} 2746 2747/// \brief Perform semantic checking of a new function declaration. 2748/// 2749/// Performs semantic analysis of the new function declaration 2750/// NewFD. This routine performs all semantic checking that does not 2751/// require the actual declarator involved in the declaration, and is 2752/// used both for the declaration of functions as they are parsed 2753/// (called via ActOnDeclarator) and for the declaration of functions 2754/// that have been instantiated via C++ template instantiation (called 2755/// via InstantiateDecl). 2756/// 2757/// This sets NewFD->isInvalidDecl() to true if there was an error. 2758void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2759 bool &Redeclaration, 2760 bool &OverloadableAttrRequired) { 2761 // If NewFD is already known erroneous, don't do any of this checking. 2762 if (NewFD->isInvalidDecl()) 2763 return; 2764 2765 if (NewFD->getResultType()->isVariablyModifiedType()) { 2766 // Functions returning a variably modified type violate C99 6.7.5.2p2 2767 // because all functions have linkage. 2768 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2769 return NewFD->setInvalidDecl(); 2770 } 2771 2772 if (NewFD->isMain(Context)) CheckMain(NewFD); 2773 2774 // Semantic checking for this function declaration (in isolation). 2775 if (getLangOptions().CPlusPlus) { 2776 // C++-specific checks. 2777 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2778 CheckConstructor(Constructor); 2779 } else if (isa<CXXDestructorDecl>(NewFD)) { 2780 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2781 QualType ClassType = Context.getTypeDeclType(Record); 2782 if (!ClassType->isDependentType()) { 2783 DeclarationName Name 2784 = Context.DeclarationNames.getCXXDestructorName( 2785 Context.getCanonicalType(ClassType)); 2786 if (NewFD->getDeclName() != Name) { 2787 Diag(NewFD->getLocation(), diag::err_destructor_name); 2788 return NewFD->setInvalidDecl(); 2789 } 2790 } 2791 Record->setUserDeclaredDestructor(true); 2792 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2793 // user-defined destructor. 2794 Record->setPOD(false); 2795 2796 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2797 // declared destructor. 2798 // FIXME: C++0x: don't do this for "= default" destructors 2799 Record->setHasTrivialDestructor(false); 2800 } else if (CXXConversionDecl *Conversion 2801 = dyn_cast<CXXConversionDecl>(NewFD)) 2802 ActOnConversionDeclarator(Conversion); 2803 2804 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2805 if (NewFD->isOverloadedOperator() && 2806 CheckOverloadedOperatorDeclaration(NewFD)) 2807 return NewFD->setInvalidDecl(); 2808 } 2809 2810 // C99 6.7.4p6: 2811 // [... ] For a function with external linkage, the following 2812 // restrictions apply: [...] If all of the file scope declarations 2813 // for a function in a translation unit include the inline 2814 // function specifier without extern, then the definition in that 2815 // translation unit is an inline definition. An inline definition 2816 // does not provide an external definition for the function, and 2817 // does not forbid an external definition in another translation 2818 // unit. 2819 // 2820 // Here we determine whether this function, in isolation, would be a 2821 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2822 // previous declarations. 2823 if (NewFD->isInline() && getLangOptions().C99 && 2824 NewFD->getStorageClass() == FunctionDecl::None && 2825 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2826 NewFD->setC99InlineDefinition(true); 2827 2828 // Check for a previous declaration of this name. 2829 if (!PrevDecl && NewFD->isExternC(Context)) { 2830 // Since we did not find anything by this name and we're declaring 2831 // an extern "C" function, look for a non-visible extern "C" 2832 // declaration with the same name. 2833 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2834 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2835 if (Pos != LocallyScopedExternalDecls.end()) 2836 PrevDecl = Pos->second; 2837 } 2838 2839 // Merge or overload the declaration with an existing declaration of 2840 // the same name, if appropriate. 2841 if (PrevDecl) { 2842 // Determine whether NewFD is an overload of PrevDecl or 2843 // a declaration that requires merging. If it's an overload, 2844 // there's no more work to do here; we'll just add the new 2845 // function to the scope. 2846 OverloadedFunctionDecl::function_iterator MatchedDecl; 2847 2848 if (!getLangOptions().CPlusPlus && 2849 AllowOverloadingOfFunction(PrevDecl, Context)) { 2850 OverloadableAttrRequired = true; 2851 2852 // Functions marked "overloadable" must have a prototype (that 2853 // we can't get through declaration merging). 2854 if (!NewFD->getType()->getAsFunctionProtoType()) { 2855 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2856 << NewFD; 2857 Redeclaration = true; 2858 2859 // Turn this into a variadic function with no parameters. 2860 QualType R = Context.getFunctionType( 2861 NewFD->getType()->getAsFunctionType()->getResultType(), 2862 0, 0, true, 0); 2863 NewFD->setType(R); 2864 return NewFD->setInvalidDecl(); 2865 } 2866 } 2867 2868 if (PrevDecl && 2869 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2870 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2871 !isa<UsingDecl>(PrevDecl)) { 2872 Redeclaration = true; 2873 Decl *OldDecl = PrevDecl; 2874 2875 // If PrevDecl was an overloaded function, extract the 2876 // FunctionDecl that matched. 2877 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2878 OldDecl = *MatchedDecl; 2879 2880 // NewFD and OldDecl represent declarations that need to be 2881 // merged. 2882 if (MergeFunctionDecl(NewFD, OldDecl)) 2883 return NewFD->setInvalidDecl(); 2884 2885 if (FunctionTemplateDecl *OldTemplateDecl 2886 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2887 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2888 else { 2889 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2890 NewFD->setAccess(OldDecl->getAccess()); 2891 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2892 } 2893 } 2894 } 2895 2896 // In C++, check default arguments now that we have merged decls. Unless 2897 // the lexical context is the class, because in this case this is done 2898 // during delayed parsing anyway. 2899 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2900 CheckCXXDefaultArguments(NewFD); 2901} 2902 2903void Sema::CheckMain(FunctionDecl* FD) { 2904 // C++ [basic.start.main]p3: A program that declares main to be inline 2905 // or static is ill-formed. 2906 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2907 // shall not appear in a declaration of main. 2908 // static main is not an error under C99, but we should warn about it. 2909 bool isInline = FD->isInline(); 2910 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2911 if (isInline || isStatic) { 2912 unsigned diagID = diag::warn_unusual_main_decl; 2913 if (isInline || getLangOptions().CPlusPlus) 2914 diagID = diag::err_unusual_main_decl; 2915 2916 int which = isStatic + (isInline << 1) - 1; 2917 Diag(FD->getLocation(), diagID) << which; 2918 } 2919 2920 QualType T = FD->getType(); 2921 assert(T->isFunctionType() && "function decl is not of function type"); 2922 const FunctionType* FT = T->getAsFunctionType(); 2923 2924 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2925 // TODO: add a replacement fixit to turn the return type into 'int'. 2926 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2927 FD->setInvalidDecl(true); 2928 } 2929 2930 // Treat protoless main() as nullary. 2931 if (isa<FunctionNoProtoType>(FT)) return; 2932 2933 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2934 unsigned nparams = FTP->getNumArgs(); 2935 assert(FD->getNumParams() == nparams); 2936 2937 if (nparams > 3) { 2938 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2939 FD->setInvalidDecl(true); 2940 nparams = 3; 2941 } 2942 2943 // FIXME: a lot of the following diagnostics would be improved 2944 // if we had some location information about types. 2945 2946 QualType CharPP = 2947 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2948 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2949 2950 for (unsigned i = 0; i < nparams; ++i) { 2951 QualType AT = FTP->getArgType(i); 2952 2953 bool mismatch = true; 2954 2955 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2956 mismatch = false; 2957 else if (Expected[i] == CharPP) { 2958 // As an extension, the following forms are okay: 2959 // char const ** 2960 // char const * const * 2961 // char * const * 2962 2963 QualifierSet qs; 2964 const PointerType* PT; 2965 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 2966 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 2967 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 2968 qs.removeConst(); 2969 mismatch = !qs.empty(); 2970 } 2971 } 2972 2973 if (mismatch) { 2974 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 2975 // TODO: suggest replacing given type with expected type 2976 FD->setInvalidDecl(true); 2977 } 2978 } 2979 2980 if (nparams == 1 && !FD->isInvalidDecl()) { 2981 Diag(FD->getLocation(), diag::warn_main_one_arg); 2982 } 2983} 2984 2985bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2986 // FIXME: Need strict checking. In C89, we need to check for 2987 // any assignment, increment, decrement, function-calls, or 2988 // commas outside of a sizeof. In C99, it's the same list, 2989 // except that the aforementioned are allowed in unevaluated 2990 // expressions. Everything else falls under the 2991 // "may accept other forms of constant expressions" exception. 2992 // (We never end up here for C++, so the constant expression 2993 // rules there don't matter.) 2994 if (Init->isConstantInitializer(Context)) 2995 return false; 2996 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2997 << Init->getSourceRange(); 2998 return true; 2999} 3000 3001void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3002 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3003} 3004 3005/// AddInitializerToDecl - Adds the initializer Init to the 3006/// declaration dcl. If DirectInit is true, this is C++ direct 3007/// initialization rather than copy initialization. 3008void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3009 Decl *RealDecl = dcl.getAs<Decl>(); 3010 // If there is no declaration, there was an error parsing it. Just ignore 3011 // the initializer. 3012 if (RealDecl == 0) 3013 return; 3014 3015 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3016 // With declarators parsed the way they are, the parser cannot 3017 // distinguish between a normal initializer and a pure-specifier. 3018 // Thus this grotesque test. 3019 IntegerLiteral *IL; 3020 Expr *Init = static_cast<Expr *>(init.get()); 3021 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3022 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3023 if (Method->isVirtualAsWritten()) { 3024 Method->setPure(); 3025 3026 // A class is abstract if at least one function is pure virtual. 3027 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3028 } else if (!Method->isInvalidDecl()) { 3029 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3030 << Method->getDeclName() << Init->getSourceRange(); 3031 Method->setInvalidDecl(); 3032 } 3033 } else { 3034 Diag(Method->getLocation(), diag::err_member_function_initialization) 3035 << Method->getDeclName() << Init->getSourceRange(); 3036 Method->setInvalidDecl(); 3037 } 3038 return; 3039 } 3040 3041 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3042 if (!VDecl) { 3043 if (getLangOptions().CPlusPlus && 3044 RealDecl->getLexicalDeclContext()->isRecord() && 3045 isa<NamedDecl>(RealDecl)) 3046 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3047 << cast<NamedDecl>(RealDecl)->getDeclName(); 3048 else 3049 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3050 RealDecl->setInvalidDecl(); 3051 return; 3052 } 3053 3054 if (!VDecl->getType()->isArrayType() && 3055 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3056 diag::err_typecheck_decl_incomplete_type)) { 3057 RealDecl->setInvalidDecl(); 3058 return; 3059 } 3060 3061 const VarDecl *Def = 0; 3062 if (VDecl->getDefinition(Def)) { 3063 Diag(VDecl->getLocation(), diag::err_redefinition) 3064 << VDecl->getDeclName(); 3065 Diag(Def->getLocation(), diag::note_previous_definition); 3066 VDecl->setInvalidDecl(); 3067 return; 3068 } 3069 3070 // Take ownership of the expression, now that we're sure we have somewhere 3071 // to put it. 3072 Expr *Init = init.takeAs<Expr>(); 3073 assert(Init && "missing initializer"); 3074 3075 // Get the decls type and save a reference for later, since 3076 // CheckInitializerTypes may change it. 3077 QualType DclT = VDecl->getType(), SavT = DclT; 3078 if (VDecl->isBlockVarDecl()) { 3079 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3080 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3081 VDecl->setInvalidDecl(); 3082 } else if (!VDecl->isInvalidDecl()) { 3083 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3084 VDecl->getDeclName(), DirectInit)) 3085 VDecl->setInvalidDecl(); 3086 3087 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3088 // Don't check invalid declarations to avoid emitting useless diagnostics. 3089 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3090 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3091 CheckForConstantInitializer(Init, DclT); 3092 } 3093 } 3094 } else if (VDecl->isStaticDataMember() && 3095 VDecl->getLexicalDeclContext()->isRecord()) { 3096 // This is an in-class initialization for a static data member, e.g., 3097 // 3098 // struct S { 3099 // static const int value = 17; 3100 // }; 3101 3102 // Attach the initializer 3103 VDecl->setInit(Context, Init); 3104 3105 // C++ [class.mem]p4: 3106 // A member-declarator can contain a constant-initializer only 3107 // if it declares a static member (9.4) of const integral or 3108 // const enumeration type, see 9.4.2. 3109 QualType T = VDecl->getType(); 3110 if (!T->isDependentType() && 3111 (!Context.getCanonicalType(T).isConstQualified() || 3112 !T->isIntegralType())) { 3113 Diag(VDecl->getLocation(), diag::err_member_initialization) 3114 << VDecl->getDeclName() << Init->getSourceRange(); 3115 VDecl->setInvalidDecl(); 3116 } else { 3117 // C++ [class.static.data]p4: 3118 // If a static data member is of const integral or const 3119 // enumeration type, its declaration in the class definition 3120 // can specify a constant-initializer which shall be an 3121 // integral constant expression (5.19). 3122 if (!Init->isTypeDependent() && 3123 !Init->getType()->isIntegralType()) { 3124 // We have a non-dependent, non-integral or enumeration type. 3125 Diag(Init->getSourceRange().getBegin(), 3126 diag::err_in_class_initializer_non_integral_type) 3127 << Init->getType() << Init->getSourceRange(); 3128 VDecl->setInvalidDecl(); 3129 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3130 // Check whether the expression is a constant expression. 3131 llvm::APSInt Value; 3132 SourceLocation Loc; 3133 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3134 Diag(Loc, diag::err_in_class_initializer_non_constant) 3135 << Init->getSourceRange(); 3136 VDecl->setInvalidDecl(); 3137 } else if (!VDecl->getType()->isDependentType()) 3138 ImpCastExprToType(Init, VDecl->getType()); 3139 } 3140 } 3141 } else if (VDecl->isFileVarDecl()) { 3142 if (VDecl->getStorageClass() == VarDecl::Extern) 3143 Diag(VDecl->getLocation(), diag::warn_extern_init); 3144 if (!VDecl->isInvalidDecl()) 3145 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3146 VDecl->getDeclName(), DirectInit)) 3147 VDecl->setInvalidDecl(); 3148 3149 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3150 // Don't check invalid declarations to avoid emitting useless diagnostics. 3151 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3152 // C99 6.7.8p4. All file scoped initializers need to be constant. 3153 CheckForConstantInitializer(Init, DclT); 3154 } 3155 } 3156 // If the type changed, it means we had an incomplete type that was 3157 // completed by the initializer. For example: 3158 // int ary[] = { 1, 3, 5 }; 3159 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3160 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3161 VDecl->setType(DclT); 3162 Init->setType(DclT); 3163 } 3164 3165 Init = MaybeCreateCXXExprWithTemporaries(Init, 3166 /*ShouldDestroyTemporaries=*/true); 3167 // Attach the initializer to the decl. 3168 VDecl->setInit(Context, Init); 3169 3170 // If the previous declaration of VDecl was a tentative definition, 3171 // remove it from the set of tentative definitions. 3172 if (VDecl->getPreviousDeclaration() && 3173 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3174 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 3175 = TentativeDefinitions.find(VDecl->getDeclName()); 3176 assert(Pos != TentativeDefinitions.end() && 3177 "Unrecorded tentative definition?"); 3178 TentativeDefinitions.erase(Pos); 3179 } 3180 3181 return; 3182} 3183 3184void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3185 bool TypeContainsUndeducedAuto) { 3186 Decl *RealDecl = dcl.getAs<Decl>(); 3187 3188 // If there is no declaration, there was an error parsing it. Just ignore it. 3189 if (RealDecl == 0) 3190 return; 3191 3192 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3193 QualType Type = Var->getType(); 3194 3195 // Record tentative definitions. 3196 if (Var->isTentativeDefinition(Context)) 3197 TentativeDefinitions[Var->getDeclName()] = Var; 3198 3199 // C++ [dcl.init.ref]p3: 3200 // The initializer can be omitted for a reference only in a 3201 // parameter declaration (8.3.5), in the declaration of a 3202 // function return type, in the declaration of a class member 3203 // within its class declaration (9.2), and where the extern 3204 // specifier is explicitly used. 3205 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3206 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3207 << Var->getDeclName() 3208 << SourceRange(Var->getLocation(), Var->getLocation()); 3209 Var->setInvalidDecl(); 3210 return; 3211 } 3212 3213 // C++0x [dcl.spec.auto]p3 3214 if (TypeContainsUndeducedAuto) { 3215 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3216 << Var->getDeclName() << Type; 3217 Var->setInvalidDecl(); 3218 return; 3219 } 3220 3221 // C++ [dcl.init]p9: 3222 // 3223 // If no initializer is specified for an object, and the object 3224 // is of (possibly cv-qualified) non-POD class type (or array 3225 // thereof), the object shall be default-initialized; if the 3226 // object is of const-qualified type, the underlying class type 3227 // shall have a user-declared default constructor. 3228 if (getLangOptions().CPlusPlus) { 3229 QualType InitType = Type; 3230 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3231 InitType = Array->getElementType(); 3232 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 3233 InitType->isRecordType() && !InitType->isDependentType()) { 3234 CXXRecordDecl *RD = 3235 cast<CXXRecordDecl>(InitType->getAs<RecordType>()->getDecl()); 3236 CXXConstructorDecl *Constructor = 0; 3237 if (!RequireCompleteType(Var->getLocation(), InitType, 3238 diag::err_invalid_incomplete_type_use)) 3239 Constructor 3240 = PerformInitializationByConstructor(InitType, 0, 0, 3241 Var->getLocation(), 3242 SourceRange(Var->getLocation(), 3243 Var->getLocation()), 3244 Var->getDeclName(), 3245 IK_Default); 3246 if (!Constructor) 3247 Var->setInvalidDecl(); 3248 else { 3249 if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()) 3250 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 3251 FinalizeVarWithDestructor(Var, InitType); 3252 } 3253 } 3254 } 3255 3256#if 0 3257 // FIXME: Temporarily disabled because we are not properly parsing 3258 // linkage specifications on declarations, e.g., 3259 // 3260 // extern "C" const CGPoint CGPointerZero; 3261 // 3262 // C++ [dcl.init]p9: 3263 // 3264 // If no initializer is specified for an object, and the 3265 // object is of (possibly cv-qualified) non-POD class type (or 3266 // array thereof), the object shall be default-initialized; if 3267 // the object is of const-qualified type, the underlying class 3268 // type shall have a user-declared default 3269 // constructor. Otherwise, if no initializer is specified for 3270 // an object, the object and its subobjects, if any, have an 3271 // indeterminate initial value; if the object or any of its 3272 // subobjects are of const-qualified type, the program is 3273 // ill-formed. 3274 // 3275 // This isn't technically an error in C, so we don't diagnose it. 3276 // 3277 // FIXME: Actually perform the POD/user-defined default 3278 // constructor check. 3279 if (getLangOptions().CPlusPlus && 3280 Context.getCanonicalType(Type).isConstQualified() && 3281 !Var->hasExternalStorage()) 3282 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3283 << Var->getName() 3284 << SourceRange(Var->getLocation(), Var->getLocation()); 3285#endif 3286 } 3287} 3288 3289Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3290 DeclPtrTy *Group, 3291 unsigned NumDecls) { 3292 llvm::SmallVector<Decl*, 8> Decls; 3293 3294 if (DS.isTypeSpecOwned()) 3295 Decls.push_back((Decl*)DS.getTypeRep()); 3296 3297 for (unsigned i = 0; i != NumDecls; ++i) 3298 if (Decl *D = Group[i].getAs<Decl>()) 3299 Decls.push_back(D); 3300 3301 // Perform semantic analysis that depends on having fully processed both 3302 // the declarator and initializer. 3303 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3304 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3305 if (!IDecl) 3306 continue; 3307 QualType T = IDecl->getType(); 3308 3309 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3310 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3311 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3312 if (!IDecl->isInvalidDecl() && 3313 RequireCompleteType(IDecl->getLocation(), T, 3314 diag::err_typecheck_decl_incomplete_type)) 3315 IDecl->setInvalidDecl(); 3316 } 3317 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3318 // object that has file scope without an initializer, and without a 3319 // storage-class specifier or with the storage-class specifier "static", 3320 // constitutes a tentative definition. Note: A tentative definition with 3321 // external linkage is valid (C99 6.2.2p5). 3322 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3323 if (const IncompleteArrayType *ArrayT 3324 = Context.getAsIncompleteArrayType(T)) { 3325 if (RequireCompleteType(IDecl->getLocation(), 3326 ArrayT->getElementType(), 3327 diag::err_illegal_decl_array_incomplete_type)) 3328 IDecl->setInvalidDecl(); 3329 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3330 // C99 6.9.2p3: If the declaration of an identifier for an object is 3331 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3332 // declared type shall not be an incomplete type. 3333 // NOTE: code such as the following 3334 // static struct s; 3335 // struct s { int a; }; 3336 // is accepted by gcc. Hence here we issue a warning instead of 3337 // an error and we do not invalidate the static declaration. 3338 // NOTE: to avoid multiple warnings, only check the first declaration. 3339 if (IDecl->getPreviousDeclaration() == 0) 3340 RequireCompleteType(IDecl->getLocation(), T, 3341 diag::ext_typecheck_decl_incomplete_type); 3342 } 3343 } 3344 } 3345 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3346 Decls.data(), Decls.size())); 3347} 3348 3349 3350/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3351/// to introduce parameters into function prototype scope. 3352Sema::DeclPtrTy 3353Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3354 const DeclSpec &DS = D.getDeclSpec(); 3355 3356 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3357 VarDecl::StorageClass StorageClass = VarDecl::None; 3358 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3359 StorageClass = VarDecl::Register; 3360 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3361 Diag(DS.getStorageClassSpecLoc(), 3362 diag::err_invalid_storage_class_in_func_decl); 3363 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3364 } 3365 3366 if (D.getDeclSpec().isThreadSpecified()) 3367 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3368 3369 DiagnoseFunctionSpecifiers(D); 3370 3371 // Check that there are no default arguments inside the type of this 3372 // parameter (C++ only). 3373 if (getLangOptions().CPlusPlus) 3374 CheckExtraCXXDefaultArguments(D); 3375 3376 TagDecl *OwnedDecl = 0; 3377 QualType parmDeclType = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedDecl); 3378 3379 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3380 // C++ [dcl.fct]p6: 3381 // Types shall not be defined in return or parameter types. 3382 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3383 << Context.getTypeDeclType(OwnedDecl); 3384 } 3385 3386 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3387 // Can this happen for params? We already checked that they don't conflict 3388 // among each other. Here they can only shadow globals, which is ok. 3389 IdentifierInfo *II = D.getIdentifier(); 3390 if (II) { 3391 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3392 if (PrevDecl->isTemplateParameter()) { 3393 // Maybe we will complain about the shadowed template parameter. 3394 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3395 // Just pretend that we didn't see the previous declaration. 3396 PrevDecl = 0; 3397 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3398 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3399 3400 // Recover by removing the name 3401 II = 0; 3402 D.SetIdentifier(0, D.getIdentifierLoc()); 3403 } 3404 } 3405 } 3406 3407 // Parameters can not be abstract class types. 3408 // For record types, this is done by the AbstractClassUsageDiagnoser once 3409 // the class has been completely parsed. 3410 if (!CurContext->isRecord() && 3411 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3412 diag::err_abstract_type_in_decl, 3413 AbstractParamType)) 3414 D.setInvalidType(true); 3415 3416 QualType T = adjustParameterType(parmDeclType); 3417 3418 ParmVarDecl *New; 3419 if (T == parmDeclType) // parameter type did not need adjustment 3420 New = ParmVarDecl::Create(Context, CurContext, 3421 D.getIdentifierLoc(), II, 3422 parmDeclType, StorageClass, 3423 0); 3424 else // keep track of both the adjusted and unadjusted types 3425 New = OriginalParmVarDecl::Create(Context, CurContext, 3426 D.getIdentifierLoc(), II, T, 3427 parmDeclType, StorageClass, 0); 3428 3429 if (D.isInvalidType()) 3430 New->setInvalidDecl(); 3431 3432 // Parameter declarators cannot be interface types. All ObjC objects are 3433 // passed by reference. 3434 if (T->isObjCInterfaceType()) { 3435 Diag(D.getIdentifierLoc(), 3436 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3437 New->setInvalidDecl(); 3438 } 3439 3440 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3441 if (D.getCXXScopeSpec().isSet()) { 3442 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3443 << D.getCXXScopeSpec().getRange(); 3444 New->setInvalidDecl(); 3445 } 3446 3447 // Add the parameter declaration into this scope. 3448 S->AddDecl(DeclPtrTy::make(New)); 3449 if (II) 3450 IdResolver.AddDecl(New); 3451 3452 ProcessDeclAttributes(S, New, D); 3453 3454 if (New->hasAttr<BlocksAttr>()) { 3455 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3456 } 3457 return DeclPtrTy::make(New); 3458} 3459 3460void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3461 SourceLocation LocAfterDecls) { 3462 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3463 "Not a function declarator!"); 3464 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3465 3466 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3467 // for a K&R function. 3468 if (!FTI.hasPrototype) { 3469 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3470 --i; 3471 if (FTI.ArgInfo[i].Param == 0) { 3472 std::string Code = " int "; 3473 Code += FTI.ArgInfo[i].Ident->getName(); 3474 Code += ";\n"; 3475 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3476 << FTI.ArgInfo[i].Ident 3477 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3478 3479 // Implicitly declare the argument as type 'int' for lack of a better 3480 // type. 3481 DeclSpec DS; 3482 const char* PrevSpec; // unused 3483 unsigned DiagID; // unused 3484 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3485 PrevSpec, DiagID); 3486 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3487 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3488 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3489 } 3490 } 3491 } 3492} 3493 3494Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3495 Declarator &D) { 3496 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3497 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3498 "Not a function declarator!"); 3499 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3500 3501 if (FTI.hasPrototype) { 3502 // FIXME: Diagnose arguments without names in C. 3503 } 3504 3505 Scope *ParentScope = FnBodyScope->getParent(); 3506 3507 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3508 MultiTemplateParamsArg(*this), 3509 /*IsFunctionDefinition=*/true); 3510 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3511} 3512 3513Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3514 if (!D) 3515 return D; 3516 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 3517 3518 CurFunctionNeedsScopeChecking = false; 3519 3520 // See if this is a redefinition. 3521 const FunctionDecl *Definition; 3522 if (FD->getBody(Definition)) { 3523 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3524 Diag(Definition->getLocation(), diag::note_previous_definition); 3525 } 3526 3527 // Builtin functions cannot be defined. 3528 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3529 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3530 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3531 FD->setInvalidDecl(); 3532 } 3533 } 3534 3535 // The return type of a function definition must be complete 3536 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3537 QualType ResultType = FD->getResultType(); 3538 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3539 !FD->isInvalidDecl() && 3540 RequireCompleteType(FD->getLocation(), ResultType, 3541 diag::err_func_def_incomplete_result)) 3542 FD->setInvalidDecl(); 3543 3544 // GNU warning -Wmissing-prototypes: 3545 // Warn if a global function is defined without a previous 3546 // prototype declaration. This warning is issued even if the 3547 // definition itself provides a prototype. The aim is to detect 3548 // global functions that fail to be declared in header files. 3549 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3550 !FD->isMain(Context)) { 3551 bool MissingPrototype = true; 3552 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3553 Prev; Prev = Prev->getPreviousDeclaration()) { 3554 // Ignore any declarations that occur in function or method 3555 // scope, because they aren't visible from the header. 3556 if (Prev->getDeclContext()->isFunctionOrMethod()) 3557 continue; 3558 3559 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3560 break; 3561 } 3562 3563 if (MissingPrototype) 3564 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3565 } 3566 3567 if (FnBodyScope) 3568 PushDeclContext(FnBodyScope, FD); 3569 3570 // Check the validity of our function parameters 3571 CheckParmsForFunctionDef(FD); 3572 3573 // Introduce our parameters into the function scope 3574 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3575 ParmVarDecl *Param = FD->getParamDecl(p); 3576 Param->setOwningFunction(FD); 3577 3578 // If this has an identifier, add it to the scope stack. 3579 if (Param->getIdentifier() && FnBodyScope) 3580 PushOnScopeChains(Param, FnBodyScope); 3581 } 3582 3583 // Checking attributes of current function definition 3584 // dllimport attribute. 3585 if (FD->getAttr<DLLImportAttr>() && 3586 (!FD->getAttr<DLLExportAttr>())) { 3587 // dllimport attribute cannot be applied to definition. 3588 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3589 Diag(FD->getLocation(), 3590 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3591 << "dllimport"; 3592 FD->setInvalidDecl(); 3593 return DeclPtrTy::make(FD); 3594 } else { 3595 // If a symbol previously declared dllimport is later defined, the 3596 // attribute is ignored in subsequent references, and a warning is 3597 // emitted. 3598 Diag(FD->getLocation(), 3599 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3600 << FD->getNameAsCString() << "dllimport"; 3601 } 3602 } 3603 return DeclPtrTy::make(FD); 3604} 3605 3606Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3607 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3608} 3609 3610Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3611 bool IsInstantiation) { 3612 Decl *dcl = D.getAs<Decl>(); 3613 Stmt *Body = BodyArg.takeAs<Stmt>(); 3614 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3615 FD->setBody(Body); 3616 if (FD->isMain(Context)) 3617 // C and C++ allow for main to automagically return 0. 3618 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3619 FD->setHasImplicitReturnZero(true); 3620 else 3621 CheckFallThroughForFunctionDef(FD, Body); 3622 3623 if (!FD->isInvalidDecl()) 3624 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3625 3626 // C++ [basic.def.odr]p2: 3627 // [...] A virtual member function is used if it is not pure. [...] 3628 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3629 if (Method->isVirtual() && !Method->isPure()) 3630 MarkDeclarationReferenced(Method->getLocation(), Method); 3631 3632 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3633 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3634 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3635 MD->setBody(Body); 3636 CheckFallThroughForFunctionDef(MD, Body); 3637 MD->setEndLoc(Body->getLocEnd()); 3638 3639 if (!MD->isInvalidDecl()) 3640 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3641 } else { 3642 Body->Destroy(Context); 3643 return DeclPtrTy(); 3644 } 3645 if (!IsInstantiation) 3646 PopDeclContext(); 3647 3648 // Verify and clean out per-function state. 3649 3650 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3651 3652 // Check goto/label use. 3653 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3654 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3655 LabelStmt *L = I->second; 3656 3657 // Verify that we have no forward references left. If so, there was a goto 3658 // or address of a label taken, but no definition of it. Label fwd 3659 // definitions are indicated with a null substmt. 3660 if (L->getSubStmt() != 0) 3661 continue; 3662 3663 // Emit error. 3664 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3665 3666 // At this point, we have gotos that use the bogus label. Stitch it into 3667 // the function body so that they aren't leaked and that the AST is well 3668 // formed. 3669 if (Body == 0) { 3670 // The whole function wasn't parsed correctly, just delete this. 3671 L->Destroy(Context); 3672 continue; 3673 } 3674 3675 // Otherwise, the body is valid: we want to stitch the label decl into the 3676 // function somewhere so that it is properly owned and so that the goto 3677 // has a valid target. Do this by creating a new compound stmt with the 3678 // label in it. 3679 3680 // Give the label a sub-statement. 3681 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3682 3683 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3684 cast<CXXTryStmt>(Body)->getTryBlock() : 3685 cast<CompoundStmt>(Body); 3686 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3687 Elements.push_back(L); 3688 Compound->setStmts(Context, &Elements[0], Elements.size()); 3689 } 3690 FunctionLabelMap.clear(); 3691 3692 if (!Body) return D; 3693 3694 // Verify that that gotos and switch cases don't jump into scopes illegally. 3695 if (CurFunctionNeedsScopeChecking) 3696 DiagnoseInvalidJumps(Body); 3697 3698 // C++ constructors that have function-try-blocks can't have return 3699 // statements in the handlers of that block. (C++ [except.handle]p14) 3700 // Verify this. 3701 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3702 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3703 3704 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3705 Destructor->computeBaseOrMembersToDestroy(Context); 3706 return D; 3707} 3708 3709/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3710/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3711NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3712 IdentifierInfo &II, Scope *S) { 3713 // Before we produce a declaration for an implicitly defined 3714 // function, see whether there was a locally-scoped declaration of 3715 // this name as a function or variable. If so, use that 3716 // (non-visible) declaration, and complain about it. 3717 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3718 = LocallyScopedExternalDecls.find(&II); 3719 if (Pos != LocallyScopedExternalDecls.end()) { 3720 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3721 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3722 return Pos->second; 3723 } 3724 3725 // Extension in C99. Legal in C90, but warn about it. 3726 if (getLangOptions().C99) 3727 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3728 else 3729 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3730 3731 // FIXME: handle stuff like: 3732 // void foo() { extern float X(); } 3733 // void bar() { X(); } <-- implicit decl for X in another scope. 3734 3735 // Set a Declarator for the implicit definition: int foo(); 3736 const char *Dummy; 3737 DeclSpec DS; 3738 unsigned DiagID; 3739 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3740 Error = Error; // Silence warning. 3741 assert(!Error && "Error setting up implicit decl!"); 3742 Declarator D(DS, Declarator::BlockContext); 3743 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3744 0, 0, false, SourceLocation(), 3745 false, 0,0,0, Loc, D), 3746 SourceLocation()); 3747 D.SetIdentifier(&II, Loc); 3748 3749 // Insert this function into translation-unit scope. 3750 3751 DeclContext *PrevDC = CurContext; 3752 CurContext = Context.getTranslationUnitDecl(); 3753 3754 FunctionDecl *FD = 3755 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3756 FD->setImplicit(); 3757 3758 CurContext = PrevDC; 3759 3760 AddKnownFunctionAttributes(FD); 3761 3762 return FD; 3763} 3764 3765/// \brief Adds any function attributes that we know a priori based on 3766/// the declaration of this function. 3767/// 3768/// These attributes can apply both to implicitly-declared builtins 3769/// (like __builtin___printf_chk) or to library-declared functions 3770/// like NSLog or printf. 3771void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3772 if (FD->isInvalidDecl()) 3773 return; 3774 3775 // If this is a built-in function, map its builtin attributes to 3776 // actual attributes. 3777 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3778 // Handle printf-formatting attributes. 3779 unsigned FormatIdx; 3780 bool HasVAListArg; 3781 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3782 if (!FD->getAttr<FormatAttr>()) 3783 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3784 HasVAListArg ? 0 : FormatIdx + 2)); 3785 } 3786 3787 // Mark const if we don't care about errno and that is the only 3788 // thing preventing the function from being const. This allows 3789 // IRgen to use LLVM intrinsics for such functions. 3790 if (!getLangOptions().MathErrno && 3791 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3792 if (!FD->getAttr<ConstAttr>()) 3793 FD->addAttr(::new (Context) ConstAttr()); 3794 } 3795 3796 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3797 FD->addAttr(::new (Context) NoReturnAttr()); 3798 } 3799 3800 IdentifierInfo *Name = FD->getIdentifier(); 3801 if (!Name) 3802 return; 3803 if ((!getLangOptions().CPlusPlus && 3804 FD->getDeclContext()->isTranslationUnit()) || 3805 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3806 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3807 LinkageSpecDecl::lang_c)) { 3808 // Okay: this could be a libc/libm/Objective-C function we know 3809 // about. 3810 } else 3811 return; 3812 3813 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3814 // FIXME: NSLog and NSLogv should be target specific 3815 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3816 // FIXME: We known better than our headers. 3817 const_cast<FormatAttr *>(Format)->setType("printf"); 3818 } else 3819 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3820 Name->isStr("NSLogv") ? 0 : 2)); 3821 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3822 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3823 // target-specific builtins, perhaps? 3824 if (!FD->getAttr<FormatAttr>()) 3825 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3826 Name->isStr("vasprintf") ? 0 : 3)); 3827 } 3828} 3829 3830TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3831 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3832 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3833 3834 // Scope manipulation handled by caller. 3835 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3836 D.getIdentifierLoc(), 3837 D.getIdentifier(), 3838 T); 3839 3840 if (TagType *TT = dyn_cast<TagType>(T)) { 3841 TagDecl *TD = TT->getDecl(); 3842 3843 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3844 // keep track of the TypedefDecl. 3845 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3846 TD->setTypedefForAnonDecl(NewTD); 3847 } 3848 3849 if (D.isInvalidType()) 3850 NewTD->setInvalidDecl(); 3851 return NewTD; 3852} 3853 3854 3855/// \brief Determine whether a tag with a given kind is acceptable 3856/// as a redeclaration of the given tag declaration. 3857/// 3858/// \returns true if the new tag kind is acceptable, false otherwise. 3859bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3860 TagDecl::TagKind NewTag, 3861 SourceLocation NewTagLoc, 3862 const IdentifierInfo &Name) { 3863 // C++ [dcl.type.elab]p3: 3864 // The class-key or enum keyword present in the 3865 // elaborated-type-specifier shall agree in kind with the 3866 // declaration to which the name in theelaborated-type-specifier 3867 // refers. This rule also applies to the form of 3868 // elaborated-type-specifier that declares a class-name or 3869 // friend class since it can be construed as referring to the 3870 // definition of the class. Thus, in any 3871 // elaborated-type-specifier, the enum keyword shall be used to 3872 // refer to an enumeration (7.2), the union class-keyshall be 3873 // used to refer to a union (clause 9), and either the class or 3874 // struct class-key shall be used to refer to a class (clause 9) 3875 // declared using the class or struct class-key. 3876 TagDecl::TagKind OldTag = Previous->getTagKind(); 3877 if (OldTag == NewTag) 3878 return true; 3879 3880 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3881 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3882 // Warn about the struct/class tag mismatch. 3883 bool isTemplate = false; 3884 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3885 isTemplate = Record->getDescribedClassTemplate(); 3886 3887 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3888 << (NewTag == TagDecl::TK_class) 3889 << isTemplate << &Name 3890 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3891 OldTag == TagDecl::TK_class? "class" : "struct"); 3892 Diag(Previous->getLocation(), diag::note_previous_use); 3893 return true; 3894 } 3895 return false; 3896} 3897 3898/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3899/// former case, Name will be non-null. In the later case, Name will be null. 3900/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3901/// reference/declaration/definition of a tag. 3902Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3903 SourceLocation KWLoc, const CXXScopeSpec &SS, 3904 IdentifierInfo *Name, SourceLocation NameLoc, 3905 AttributeList *Attr, AccessSpecifier AS, 3906 MultiTemplateParamsArg TemplateParameterLists, 3907 bool &OwnedDecl) { 3908 // If this is not a definition, it must have a name. 3909 assert((Name != 0 || TUK == TUK_Definition) && 3910 "Nameless record must be a definition!"); 3911 3912 OwnedDecl = false; 3913 TagDecl::TagKind Kind; 3914 switch (TagSpec) { 3915 default: assert(0 && "Unknown tag type!"); 3916 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3917 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3918 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3919 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3920 } 3921 3922 if (TUK != TUK_Reference) { 3923 if (TemplateParameterList *TemplateParams 3924 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3925 (TemplateParameterList**)TemplateParameterLists.get(), 3926 TemplateParameterLists.size())) { 3927 if (TemplateParams->size() > 0) { 3928 // This is a declaration or definition of a class template (which may 3929 // be a member of another template). 3930 OwnedDecl = false; 3931 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 3932 SS, Name, NameLoc, Attr, 3933 move(TemplateParameterLists), 3934 AS); 3935 return Result.get(); 3936 } else { 3937 // FIXME: diagnose the extraneous 'template<>', once we recover 3938 // slightly better in ParseTemplate.cpp from bogus template 3939 // parameters. 3940 } 3941 } 3942 } 3943 3944 DeclContext *SearchDC = CurContext; 3945 DeclContext *DC = CurContext; 3946 NamedDecl *PrevDecl = 0; 3947 3948 bool Invalid = false; 3949 3950 if (Name && SS.isNotEmpty()) { 3951 // We have a nested-name tag ('struct foo::bar'). 3952 3953 // Check for invalid 'foo::'. 3954 if (SS.isInvalid()) { 3955 Name = 0; 3956 goto CreateNewDecl; 3957 } 3958 3959 if (RequireCompleteDeclContext(SS)) 3960 return DeclPtrTy::make((Decl *)0); 3961 3962 DC = computeDeclContext(SS, true); 3963 SearchDC = DC; 3964 // Look-up name inside 'foo::'. 3965 PrevDecl 3966 = dyn_cast_or_null<TagDecl>( 3967 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3968 3969 // A tag 'foo::bar' must already exist. 3970 if (PrevDecl == 0) { 3971 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3972 Name = 0; 3973 Invalid = true; 3974 goto CreateNewDecl; 3975 } 3976 } else if (Name) { 3977 // If this is a named struct, check to see if there was a previous forward 3978 // declaration or definition. 3979 // FIXME: We're looking into outer scopes here, even when we 3980 // shouldn't be. Doing so can result in ambiguities that we 3981 // shouldn't be diagnosing. 3982 LookupResult R = LookupName(S, Name, LookupTagName, 3983 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 3984 if (R.isAmbiguous()) { 3985 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3986 // FIXME: This is not best way to recover from case like: 3987 // 3988 // struct S s; 3989 // 3990 // causes needless "incomplete type" error later. 3991 Name = 0; 3992 PrevDecl = 0; 3993 Invalid = true; 3994 } else 3995 PrevDecl = R; 3996 3997 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 3998 // FIXME: This makes sure that we ignore the contexts associated 3999 // with C structs, unions, and enums when looking for a matching 4000 // tag declaration or definition. See the similar lookup tweak 4001 // in Sema::LookupName; is there a better way to deal with this? 4002 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4003 SearchDC = SearchDC->getParent(); 4004 } 4005 } 4006 4007 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4008 // Maybe we will complain about the shadowed template parameter. 4009 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4010 // Just pretend that we didn't see the previous declaration. 4011 PrevDecl = 0; 4012 } 4013 4014 if (PrevDecl) { 4015 // Check whether the previous declaration is usable. 4016 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4017 4018 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4019 // If this is a use of a previous tag, or if the tag is already declared 4020 // in the same scope (so that the definition/declaration completes or 4021 // rementions the tag), reuse the decl. 4022 if (TUK == TUK_Reference || TUK == TUK_Friend || 4023 isDeclInScope(PrevDecl, SearchDC, S)) { 4024 // Make sure that this wasn't declared as an enum and now used as a 4025 // struct or something similar. 4026 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4027 bool SafeToContinue 4028 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4029 Kind != TagDecl::TK_enum); 4030 if (SafeToContinue) 4031 Diag(KWLoc, diag::err_use_with_wrong_tag) 4032 << Name 4033 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4034 PrevTagDecl->getKindName()); 4035 else 4036 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4037 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4038 4039 if (SafeToContinue) 4040 Kind = PrevTagDecl->getTagKind(); 4041 else { 4042 // Recover by making this an anonymous redefinition. 4043 Name = 0; 4044 PrevDecl = 0; 4045 Invalid = true; 4046 } 4047 } 4048 4049 if (!Invalid) { 4050 // If this is a use, just return the declaration we found. 4051 4052 // FIXME: In the future, return a variant or some other clue 4053 // for the consumer of this Decl to know it doesn't own it. 4054 // For our current ASTs this shouldn't be a problem, but will 4055 // need to be changed with DeclGroups. 4056 if (TUK == TUK_Reference) 4057 return DeclPtrTy::make(PrevDecl); 4058 4059 // If this is a friend, make sure we create the new 4060 // declaration in the appropriate semantic context. 4061 if (TUK == TUK_Friend) 4062 SearchDC = PrevDecl->getDeclContext(); 4063 4064 // Diagnose attempts to redefine a tag. 4065 if (TUK == TUK_Definition) { 4066 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4067 Diag(NameLoc, diag::err_redefinition) << Name; 4068 Diag(Def->getLocation(), diag::note_previous_definition); 4069 // If this is a redefinition, recover by making this 4070 // struct be anonymous, which will make any later 4071 // references get the previous definition. 4072 Name = 0; 4073 PrevDecl = 0; 4074 Invalid = true; 4075 } else { 4076 // If the type is currently being defined, complain 4077 // about a nested redefinition. 4078 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4079 if (Tag->isBeingDefined()) { 4080 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4081 Diag(PrevTagDecl->getLocation(), 4082 diag::note_previous_definition); 4083 Name = 0; 4084 PrevDecl = 0; 4085 Invalid = true; 4086 } 4087 } 4088 4089 // Okay, this is definition of a previously declared or referenced 4090 // tag PrevDecl. We're going to create a new Decl for it. 4091 } 4092 } 4093 // If we get here we have (another) forward declaration or we 4094 // have a definition. Just create a new decl. 4095 4096 } else { 4097 // If we get here, this is a definition of a new tag type in a nested 4098 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4099 // new decl/type. We set PrevDecl to NULL so that the entities 4100 // have distinct types. 4101 PrevDecl = 0; 4102 } 4103 // If we get here, we're going to create a new Decl. If PrevDecl 4104 // is non-NULL, it's a definition of the tag declared by 4105 // PrevDecl. If it's NULL, we have a new definition. 4106 } else { 4107 // PrevDecl is a namespace, template, or anything else 4108 // that lives in the IDNS_Tag identifier namespace. 4109 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4110 // The tag name clashes with a namespace name, issue an error and 4111 // recover by making this tag be anonymous. 4112 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4113 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4114 Name = 0; 4115 PrevDecl = 0; 4116 Invalid = true; 4117 } else { 4118 // The existing declaration isn't relevant to us; we're in a 4119 // new scope, so clear out the previous declaration. 4120 PrevDecl = 0; 4121 } 4122 } 4123 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4124 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4125 // C++ [basic.scope.pdecl]p5: 4126 // -- for an elaborated-type-specifier of the form 4127 // 4128 // class-key identifier 4129 // 4130 // if the elaborated-type-specifier is used in the 4131 // decl-specifier-seq or parameter-declaration-clause of a 4132 // function defined in namespace scope, the identifier is 4133 // declared as a class-name in the namespace that contains 4134 // the declaration; otherwise, except as a friend 4135 // declaration, the identifier is declared in the smallest 4136 // non-class, non-function-prototype scope that contains the 4137 // declaration. 4138 // 4139 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4140 // C structs and unions. 4141 // 4142 // GNU C also supports this behavior as part of its incomplete 4143 // enum types extension, while GNU C++ does not. 4144 // 4145 // Find the context where we'll be declaring the tag. 4146 // FIXME: We would like to maintain the current DeclContext as the 4147 // lexical context, 4148 while (SearchDC->isRecord()) 4149 SearchDC = SearchDC->getParent(); 4150 4151 // Find the scope where we'll be declaring the tag. 4152 while (S->isClassScope() || 4153 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4154 ((S->getFlags() & Scope::DeclScope) == 0) || 4155 (S->getEntity() && 4156 ((DeclContext *)S->getEntity())->isTransparentContext())) 4157 S = S->getParent(); 4158 4159 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4160 // C++ [namespace.memdef]p3: 4161 // If a friend declaration in a non-local class first declares a 4162 // class or function, the friend class or function is a member of 4163 // the innermost enclosing namespace. 4164 while (!SearchDC->isFileContext()) 4165 SearchDC = SearchDC->getParent(); 4166 4167 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4168 while (S->getEntity() != SearchDC) 4169 S = S->getParent(); 4170 } 4171 4172CreateNewDecl: 4173 4174 // If there is an identifier, use the location of the identifier as the 4175 // location of the decl, otherwise use the location of the struct/union 4176 // keyword. 4177 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4178 4179 // Otherwise, create a new declaration. If there is a previous 4180 // declaration of the same entity, the two will be linked via 4181 // PrevDecl. 4182 TagDecl *New; 4183 4184 if (Kind == TagDecl::TK_enum) { 4185 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4186 // enum X { A, B, C } D; D should chain to X. 4187 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4188 cast_or_null<EnumDecl>(PrevDecl)); 4189 // If this is an undefined enum, warn. 4190 if (TUK != TUK_Definition && !Invalid) { 4191 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4192 : diag::ext_forward_ref_enum; 4193 Diag(Loc, DK); 4194 } 4195 } else { 4196 // struct/union/class 4197 4198 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4199 // struct X { int A; } D; D should chain to X. 4200 if (getLangOptions().CPlusPlus) 4201 // FIXME: Look for a way to use RecordDecl for simple structs. 4202 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4203 cast_or_null<CXXRecordDecl>(PrevDecl)); 4204 else 4205 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4206 cast_or_null<RecordDecl>(PrevDecl)); 4207 } 4208 4209 if (Kind != TagDecl::TK_enum) { 4210 // Handle #pragma pack: if the #pragma pack stack has non-default 4211 // alignment, make up a packed attribute for this decl. These 4212 // attributes are checked when the ASTContext lays out the 4213 // structure. 4214 // 4215 // It is important for implementing the correct semantics that this 4216 // happen here (in act on tag decl). The #pragma pack stack is 4217 // maintained as a result of parser callbacks which can occur at 4218 // many points during the parsing of a struct declaration (because 4219 // the #pragma tokens are effectively skipped over during the 4220 // parsing of the struct). 4221 if (unsigned Alignment = getPragmaPackAlignment()) 4222 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4223 } 4224 4225 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4226 // C++ [dcl.typedef]p3: 4227 // [...] Similarly, in a given scope, a class or enumeration 4228 // shall not be declared with the same name as a typedef-name 4229 // that is declared in that scope and refers to a type other 4230 // than the class or enumeration itself. 4231 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4232 TypedefDecl *PrevTypedef = 0; 4233 if (Lookup.getKind() == LookupResult::Found) 4234 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4235 4236 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4237 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4238 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4239 Diag(Loc, diag::err_tag_definition_of_typedef) 4240 << Context.getTypeDeclType(New) 4241 << PrevTypedef->getUnderlyingType(); 4242 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4243 Invalid = true; 4244 } 4245 } 4246 4247 if (Invalid) 4248 New->setInvalidDecl(); 4249 4250 if (Attr) 4251 ProcessDeclAttributeList(S, New, Attr); 4252 4253 // If we're declaring or defining a tag in function prototype scope 4254 // in C, note that this type can only be used within the function. 4255 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4256 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4257 4258 // Set the lexical context. If the tag has a C++ scope specifier, the 4259 // lexical context will be different from the semantic context. 4260 New->setLexicalDeclContext(CurContext); 4261 4262 // Set the access specifier. 4263 if (!Invalid && TUK != TUK_Friend) 4264 SetMemberAccessSpecifier(New, PrevDecl, AS); 4265 4266 if (TUK == TUK_Definition) 4267 New->startDefinition(); 4268 4269 // If this has an identifier, add it to the scope stack. 4270 if (Name && TUK != TUK_Friend) { 4271 S = getNonFieldDeclScope(S); 4272 PushOnScopeChains(New, S); 4273 } else { 4274 CurContext->addDecl(New); 4275 } 4276 4277 // If this is the C FILE type, notify the AST context. 4278 if (IdentifierInfo *II = New->getIdentifier()) 4279 if (!New->isInvalidDecl() && 4280 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4281 II->isStr("FILE")) 4282 Context.setFILEDecl(New); 4283 4284 OwnedDecl = true; 4285 return DeclPtrTy::make(New); 4286} 4287 4288void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4289 AdjustDeclIfTemplate(TagD); 4290 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4291 4292 // Enter the tag context. 4293 PushDeclContext(S, Tag); 4294 4295 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4296 FieldCollector->StartClass(); 4297 4298 if (Record->getIdentifier()) { 4299 // C++ [class]p2: 4300 // [...] The class-name is also inserted into the scope of the 4301 // class itself; this is known as the injected-class-name. For 4302 // purposes of access checking, the injected-class-name is treated 4303 // as if it were a public member name. 4304 CXXRecordDecl *InjectedClassName 4305 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4306 CurContext, Record->getLocation(), 4307 Record->getIdentifier(), 4308 Record->getTagKeywordLoc(), 4309 Record); 4310 InjectedClassName->setImplicit(); 4311 InjectedClassName->setAccess(AS_public); 4312 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4313 InjectedClassName->setDescribedClassTemplate(Template); 4314 PushOnScopeChains(InjectedClassName, S); 4315 assert(InjectedClassName->isInjectedClassName() && 4316 "Broken injected-class-name"); 4317 } 4318 } 4319} 4320 4321void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4322 SourceLocation RBraceLoc) { 4323 AdjustDeclIfTemplate(TagD); 4324 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4325 Tag->setRBraceLoc(RBraceLoc); 4326 4327 if (isa<CXXRecordDecl>(Tag)) 4328 FieldCollector->FinishClass(); 4329 4330 // Exit this scope of this tag's definition. 4331 PopDeclContext(); 4332 4333 // Notify the consumer that we've defined a tag. 4334 Consumer.HandleTagDeclDefinition(Tag); 4335} 4336 4337// Note that FieldName may be null for anonymous bitfields. 4338bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4339 QualType FieldTy, const Expr *BitWidth, 4340 bool *ZeroWidth) { 4341 // Default to true; that shouldn't confuse checks for emptiness 4342 if (ZeroWidth) 4343 *ZeroWidth = true; 4344 4345 // C99 6.7.2.1p4 - verify the field type. 4346 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4347 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4348 // Handle incomplete types with specific error. 4349 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4350 return true; 4351 if (FieldName) 4352 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4353 << FieldName << FieldTy << BitWidth->getSourceRange(); 4354 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4355 << FieldTy << BitWidth->getSourceRange(); 4356 } 4357 4358 // If the bit-width is type- or value-dependent, don't try to check 4359 // it now. 4360 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4361 return false; 4362 4363 llvm::APSInt Value; 4364 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4365 return true; 4366 4367 if (Value != 0 && ZeroWidth) 4368 *ZeroWidth = false; 4369 4370 // Zero-width bitfield is ok for anonymous field. 4371 if (Value == 0 && FieldName) 4372 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4373 4374 if (Value.isSigned() && Value.isNegative()) { 4375 if (FieldName) 4376 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4377 << FieldName << Value.toString(10); 4378 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4379 << Value.toString(10); 4380 } 4381 4382 if (!FieldTy->isDependentType()) { 4383 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4384 if (Value.getZExtValue() > TypeSize) { 4385 if (FieldName) 4386 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4387 << FieldName << (unsigned)TypeSize; 4388 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4389 << (unsigned)TypeSize; 4390 } 4391 } 4392 4393 return false; 4394} 4395 4396/// ActOnField - Each field of a struct/union/class is passed into this in order 4397/// to create a FieldDecl object for it. 4398Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4399 SourceLocation DeclStart, 4400 Declarator &D, ExprTy *BitfieldWidth) { 4401 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4402 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4403 AS_public); 4404 return DeclPtrTy::make(Res); 4405} 4406 4407/// HandleField - Analyze a field of a C struct or a C++ data member. 4408/// 4409FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4410 SourceLocation DeclStart, 4411 Declarator &D, Expr *BitWidth, 4412 AccessSpecifier AS) { 4413 IdentifierInfo *II = D.getIdentifier(); 4414 SourceLocation Loc = DeclStart; 4415 if (II) Loc = D.getIdentifierLoc(); 4416 4417 QualType T = GetTypeForDeclarator(D, S); 4418 if (getLangOptions().CPlusPlus) 4419 CheckExtraCXXDefaultArguments(D); 4420 4421 DiagnoseFunctionSpecifiers(D); 4422 4423 if (D.getDeclSpec().isThreadSpecified()) 4424 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4425 4426 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4427 4428 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4429 // Maybe we will complain about the shadowed template parameter. 4430 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4431 // Just pretend that we didn't see the previous declaration. 4432 PrevDecl = 0; 4433 } 4434 4435 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4436 PrevDecl = 0; 4437 4438 bool Mutable 4439 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4440 SourceLocation TSSL = D.getSourceRange().getBegin(); 4441 FieldDecl *NewFD 4442 = CheckFieldDecl(II, T, Record, Loc, Mutable, BitWidth, TSSL, 4443 AS, PrevDecl, &D); 4444 if (NewFD->isInvalidDecl() && PrevDecl) { 4445 // Don't introduce NewFD into scope; there's already something 4446 // with the same name in the same scope. 4447 } else if (II) { 4448 PushOnScopeChains(NewFD, S); 4449 } else 4450 Record->addDecl(NewFD); 4451 4452 return NewFD; 4453} 4454 4455/// \brief Build a new FieldDecl and check its well-formedness. 4456/// 4457/// This routine builds a new FieldDecl given the fields name, type, 4458/// record, etc. \p PrevDecl should refer to any previous declaration 4459/// with the same name and in the same scope as the field to be 4460/// created. 4461/// 4462/// \returns a new FieldDecl. 4463/// 4464/// \todo The Declarator argument is a hack. It will be removed once 4465FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4466 RecordDecl *Record, SourceLocation Loc, 4467 bool Mutable, Expr *BitWidth, 4468 SourceLocation TSSL, 4469 AccessSpecifier AS, NamedDecl *PrevDecl, 4470 Declarator *D) { 4471 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4472 bool InvalidDecl = false; 4473 if (D) InvalidDecl = D->isInvalidType(); 4474 4475 // If we receive a broken type, recover by assuming 'int' and 4476 // marking this declaration as invalid. 4477 if (T.isNull()) { 4478 InvalidDecl = true; 4479 T = Context.IntTy; 4480 } 4481 4482 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4483 // than a variably modified type. 4484 if (T->isVariablyModifiedType()) { 4485 bool SizeIsNegative; 4486 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4487 SizeIsNegative); 4488 if (!FixedTy.isNull()) { 4489 Diag(Loc, diag::warn_illegal_constant_array_size); 4490 T = FixedTy; 4491 } else { 4492 if (SizeIsNegative) 4493 Diag(Loc, diag::err_typecheck_negative_array_size); 4494 else 4495 Diag(Loc, diag::err_typecheck_field_variable_size); 4496 InvalidDecl = true; 4497 } 4498 } 4499 4500 // Fields can not have abstract class types 4501 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4502 AbstractFieldType)) 4503 InvalidDecl = true; 4504 4505 bool ZeroWidth = false; 4506 // If this is declared as a bit-field, check the bit-field. 4507 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4508 InvalidDecl = true; 4509 DeleteExpr(BitWidth); 4510 BitWidth = 0; 4511 ZeroWidth = false; 4512 } 4513 4514 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 4515 Mutable, TSSL); 4516 if (InvalidDecl) 4517 NewFD->setInvalidDecl(); 4518 4519 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4520 Diag(Loc, diag::err_duplicate_member) << II; 4521 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4522 NewFD->setInvalidDecl(); 4523 } 4524 4525 if (getLangOptions().CPlusPlus) { 4526 QualType EltTy = Context.getBaseElementType(T); 4527 4528 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4529 4530 if (!T->isPODType()) 4531 CXXRecord->setPOD(false); 4532 if (!ZeroWidth) 4533 CXXRecord->setEmpty(false); 4534 4535 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4536 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4537 4538 if (!RDecl->hasTrivialConstructor()) 4539 CXXRecord->setHasTrivialConstructor(false); 4540 if (!RDecl->hasTrivialCopyConstructor()) 4541 CXXRecord->setHasTrivialCopyConstructor(false); 4542 if (!RDecl->hasTrivialCopyAssignment()) 4543 CXXRecord->setHasTrivialCopyAssignment(false); 4544 if (!RDecl->hasTrivialDestructor()) 4545 CXXRecord->setHasTrivialDestructor(false); 4546 4547 // C++ 9.5p1: An object of a class with a non-trivial 4548 // constructor, a non-trivial copy constructor, a non-trivial 4549 // destructor, or a non-trivial copy assignment operator 4550 // cannot be a member of a union, nor can an array of such 4551 // objects. 4552 // TODO: C++0x alters this restriction significantly. 4553 if (Record->isUnion()) { 4554 // We check for copy constructors before constructors 4555 // because otherwise we'll never get complaints about 4556 // copy constructors. 4557 4558 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4559 4560 CXXSpecialMember member; 4561 if (!RDecl->hasTrivialCopyConstructor()) 4562 member = CXXCopyConstructor; 4563 else if (!RDecl->hasTrivialConstructor()) 4564 member = CXXDefaultConstructor; 4565 else if (!RDecl->hasTrivialCopyAssignment()) 4566 member = CXXCopyAssignment; 4567 else if (!RDecl->hasTrivialDestructor()) 4568 member = CXXDestructor; 4569 else 4570 member = invalid; 4571 4572 if (member != invalid) { 4573 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4574 DiagnoseNontrivial(RT, member); 4575 NewFD->setInvalidDecl(); 4576 } 4577 } 4578 } 4579 } 4580 4581 // FIXME: We need to pass in the attributes given an AST 4582 // representation, not a parser representation. 4583 if (D) 4584 // FIXME: What to pass instead of TUScope? 4585 ProcessDeclAttributes(TUScope, NewFD, *D); 4586 4587 if (T.isObjCGCWeak()) 4588 Diag(Loc, diag::warn_attribute_weak_on_field); 4589 4590 NewFD->setAccess(AS); 4591 4592 // C++ [dcl.init.aggr]p1: 4593 // An aggregate is an array or a class (clause 9) with [...] no 4594 // private or protected non-static data members (clause 11). 4595 // A POD must be an aggregate. 4596 if (getLangOptions().CPlusPlus && 4597 (AS == AS_private || AS == AS_protected)) { 4598 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4599 CXXRecord->setAggregate(false); 4600 CXXRecord->setPOD(false); 4601 } 4602 4603 return NewFD; 4604} 4605 4606/// DiagnoseNontrivial - Given that a class has a non-trivial 4607/// special member, figure out why. 4608void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4609 QualType QT(T, 0U); 4610 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4611 4612 // Check whether the member was user-declared. 4613 switch (member) { 4614 case CXXDefaultConstructor: 4615 if (RD->hasUserDeclaredConstructor()) { 4616 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4617 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4618 if (!ci->isImplicitlyDefined(Context)) { 4619 SourceLocation CtorLoc = ci->getLocation(); 4620 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4621 return; 4622 } 4623 4624 assert(0 && "found no user-declared constructors"); 4625 return; 4626 } 4627 break; 4628 4629 case CXXCopyConstructor: 4630 if (RD->hasUserDeclaredCopyConstructor()) { 4631 SourceLocation CtorLoc = 4632 RD->getCopyConstructor(Context, 0)->getLocation(); 4633 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4634 return; 4635 } 4636 break; 4637 4638 case CXXCopyAssignment: 4639 if (RD->hasUserDeclaredCopyAssignment()) { 4640 // FIXME: this should use the location of the copy 4641 // assignment, not the type. 4642 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4643 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4644 return; 4645 } 4646 break; 4647 4648 case CXXDestructor: 4649 if (RD->hasUserDeclaredDestructor()) { 4650 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4651 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4652 return; 4653 } 4654 break; 4655 } 4656 4657 typedef CXXRecordDecl::base_class_iterator base_iter; 4658 4659 // Virtual bases and members inhibit trivial copying/construction, 4660 // but not trivial destruction. 4661 if (member != CXXDestructor) { 4662 // Check for virtual bases. vbases includes indirect virtual bases, 4663 // so we just iterate through the direct bases. 4664 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4665 if (bi->isVirtual()) { 4666 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4667 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4668 return; 4669 } 4670 4671 // Check for virtual methods. 4672 typedef CXXRecordDecl::method_iterator meth_iter; 4673 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4674 ++mi) { 4675 if (mi->isVirtual()) { 4676 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4677 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4678 return; 4679 } 4680 } 4681 } 4682 4683 bool (CXXRecordDecl::*hasTrivial)() const; 4684 switch (member) { 4685 case CXXDefaultConstructor: 4686 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4687 case CXXCopyConstructor: 4688 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4689 case CXXCopyAssignment: 4690 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4691 case CXXDestructor: 4692 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4693 default: 4694 assert(0 && "unexpected special member"); return; 4695 } 4696 4697 // Check for nontrivial bases (and recurse). 4698 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4699 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4700 assert(BaseRT); 4701 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4702 if (!(BaseRecTy->*hasTrivial)()) { 4703 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4704 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4705 DiagnoseNontrivial(BaseRT, member); 4706 return; 4707 } 4708 } 4709 4710 // Check for nontrivial members (and recurse). 4711 typedef RecordDecl::field_iterator field_iter; 4712 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4713 ++fi) { 4714 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4715 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4716 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4717 4718 if (!(EltRD->*hasTrivial)()) { 4719 SourceLocation FLoc = (*fi)->getLocation(); 4720 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4721 DiagnoseNontrivial(EltRT, member); 4722 return; 4723 } 4724 } 4725 } 4726 4727 assert(0 && "found no explanation for non-trivial member"); 4728} 4729 4730/// TranslateIvarVisibility - Translate visibility from a token ID to an 4731/// AST enum value. 4732static ObjCIvarDecl::AccessControl 4733TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4734 switch (ivarVisibility) { 4735 default: assert(0 && "Unknown visitibility kind"); 4736 case tok::objc_private: return ObjCIvarDecl::Private; 4737 case tok::objc_public: return ObjCIvarDecl::Public; 4738 case tok::objc_protected: return ObjCIvarDecl::Protected; 4739 case tok::objc_package: return ObjCIvarDecl::Package; 4740 } 4741} 4742 4743/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4744/// in order to create an IvarDecl object for it. 4745Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4746 SourceLocation DeclStart, 4747 DeclPtrTy IntfDecl, 4748 Declarator &D, ExprTy *BitfieldWidth, 4749 tok::ObjCKeywordKind Visibility) { 4750 4751 IdentifierInfo *II = D.getIdentifier(); 4752 Expr *BitWidth = (Expr*)BitfieldWidth; 4753 SourceLocation Loc = DeclStart; 4754 if (II) Loc = D.getIdentifierLoc(); 4755 4756 // FIXME: Unnamed fields can be handled in various different ways, for 4757 // example, unnamed unions inject all members into the struct namespace! 4758 4759 QualType T = GetTypeForDeclarator(D, S); 4760 4761 if (BitWidth) { 4762 // 6.7.2.1p3, 6.7.2.1p4 4763 if (VerifyBitField(Loc, II, T, BitWidth)) { 4764 D.setInvalidType(); 4765 DeleteExpr(BitWidth); 4766 BitWidth = 0; 4767 } 4768 } else { 4769 // Not a bitfield. 4770 4771 // validate II. 4772 4773 } 4774 4775 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4776 // than a variably modified type. 4777 if (T->isVariablyModifiedType()) { 4778 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4779 D.setInvalidType(); 4780 } 4781 4782 // Get the visibility (access control) for this ivar. 4783 ObjCIvarDecl::AccessControl ac = 4784 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4785 : ObjCIvarDecl::None; 4786 // Must set ivar's DeclContext to its enclosing interface. 4787 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4788 DeclContext *EnclosingContext; 4789 if (ObjCImplementationDecl *IMPDecl = 4790 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4791 // Case of ivar declared in an implementation. Context is that of its class. 4792 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4793 assert(IDecl && "No class- ActOnIvar"); 4794 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4795 } else 4796 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4797 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4798 4799 // Construct the decl. 4800 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4801 EnclosingContext, Loc, II, T,ac, 4802 (Expr *)BitfieldWidth); 4803 4804 if (II) { 4805 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4806 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4807 && !isa<TagDecl>(PrevDecl)) { 4808 Diag(Loc, diag::err_duplicate_member) << II; 4809 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4810 NewID->setInvalidDecl(); 4811 } 4812 } 4813 4814 // Process attributes attached to the ivar. 4815 ProcessDeclAttributes(S, NewID, D); 4816 4817 if (D.isInvalidType()) 4818 NewID->setInvalidDecl(); 4819 4820 if (II) { 4821 // FIXME: When interfaces are DeclContexts, we'll need to add 4822 // these to the interface. 4823 S->AddDecl(DeclPtrTy::make(NewID)); 4824 IdResolver.AddDecl(NewID); 4825 } 4826 4827 return DeclPtrTy::make(NewID); 4828} 4829 4830void Sema::ActOnFields(Scope* S, 4831 SourceLocation RecLoc, DeclPtrTy RecDecl, 4832 DeclPtrTy *Fields, unsigned NumFields, 4833 SourceLocation LBrac, SourceLocation RBrac, 4834 AttributeList *Attr) { 4835 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4836 assert(EnclosingDecl && "missing record or interface decl"); 4837 4838 // If the decl this is being inserted into is invalid, then it may be a 4839 // redeclaration or some other bogus case. Don't try to add fields to it. 4840 if (EnclosingDecl->isInvalidDecl()) { 4841 // FIXME: Deallocate fields? 4842 return; 4843 } 4844 4845 4846 // Verify that all the fields are okay. 4847 unsigned NumNamedMembers = 0; 4848 llvm::SmallVector<FieldDecl*, 32> RecFields; 4849 4850 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4851 for (unsigned i = 0; i != NumFields; ++i) { 4852 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4853 4854 // Get the type for the field. 4855 Type *FDTy = FD->getType().getTypePtr(); 4856 4857 if (!FD->isAnonymousStructOrUnion()) { 4858 // Remember all fields written by the user. 4859 RecFields.push_back(FD); 4860 } 4861 4862 // If the field is already invalid for some reason, don't emit more 4863 // diagnostics about it. 4864 if (FD->isInvalidDecl()) 4865 continue; 4866 4867 // C99 6.7.2.1p2: 4868 // A structure or union shall not contain a member with 4869 // incomplete or function type (hence, a structure shall not 4870 // contain an instance of itself, but may contain a pointer to 4871 // an instance of itself), except that the last member of a 4872 // structure with more than one named member may have incomplete 4873 // array type; such a structure (and any union containing, 4874 // possibly recursively, a member that is such a structure) 4875 // shall not be a member of a structure or an element of an 4876 // array. 4877 if (FDTy->isFunctionType()) { 4878 // Field declared as a function. 4879 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4880 << FD->getDeclName(); 4881 FD->setInvalidDecl(); 4882 EnclosingDecl->setInvalidDecl(); 4883 continue; 4884 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4885 Record && Record->isStruct()) { 4886 // Flexible array member. 4887 if (NumNamedMembers < 1) { 4888 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4889 << FD->getDeclName(); 4890 FD->setInvalidDecl(); 4891 EnclosingDecl->setInvalidDecl(); 4892 continue; 4893 } 4894 // Okay, we have a legal flexible array member at the end of the struct. 4895 if (Record) 4896 Record->setHasFlexibleArrayMember(true); 4897 } else if (!FDTy->isDependentType() && 4898 RequireCompleteType(FD->getLocation(), FD->getType(), 4899 diag::err_field_incomplete)) { 4900 // Incomplete type 4901 FD->setInvalidDecl(); 4902 EnclosingDecl->setInvalidDecl(); 4903 continue; 4904 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 4905 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4906 // If this is a member of a union, then entire union becomes "flexible". 4907 if (Record && Record->isUnion()) { 4908 Record->setHasFlexibleArrayMember(true); 4909 } else { 4910 // If this is a struct/class and this is not the last element, reject 4911 // it. Note that GCC supports variable sized arrays in the middle of 4912 // structures. 4913 if (i != NumFields-1) 4914 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4915 << FD->getDeclName() << FD->getType(); 4916 else { 4917 // We support flexible arrays at the end of structs in 4918 // other structs as an extension. 4919 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4920 << FD->getDeclName(); 4921 if (Record) 4922 Record->setHasFlexibleArrayMember(true); 4923 } 4924 } 4925 } 4926 if (Record && FDTTy->getDecl()->hasObjectMember()) 4927 Record->setHasObjectMember(true); 4928 } else if (FDTy->isObjCInterfaceType()) { 4929 /// A field cannot be an Objective-c object 4930 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4931 FD->setInvalidDecl(); 4932 EnclosingDecl->setInvalidDecl(); 4933 continue; 4934 } else if (getLangOptions().ObjC1 && 4935 getLangOptions().getGCMode() != LangOptions::NonGC && 4936 Record && 4937 (FD->getType()->isObjCObjectPointerType() || 4938 FD->getType().isObjCGCStrong())) 4939 Record->setHasObjectMember(true); 4940 // Keep track of the number of named members. 4941 if (FD->getIdentifier()) 4942 ++NumNamedMembers; 4943 } 4944 4945 // Okay, we successfully defined 'Record'. 4946 if (Record) { 4947 Record->completeDefinition(Context); 4948 } else { 4949 ObjCIvarDecl **ClsFields = 4950 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4951 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4952 ID->setIVarList(ClsFields, RecFields.size(), Context); 4953 ID->setLocEnd(RBrac); 4954 // Add ivar's to class's DeclContext. 4955 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4956 ClsFields[i]->setLexicalDeclContext(ID); 4957 ID->addDecl(ClsFields[i]); 4958 } 4959 // Must enforce the rule that ivars in the base classes may not be 4960 // duplicates. 4961 if (ID->getSuperClass()) { 4962 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4963 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4964 ObjCIvarDecl* Ivar = (*IVI); 4965 4966 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4967 ObjCIvarDecl* prevIvar = 4968 ID->getSuperClass()->lookupInstanceVariable(II); 4969 if (prevIvar) { 4970 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4971 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4972 } 4973 } 4974 } 4975 } 4976 } else if (ObjCImplementationDecl *IMPDecl = 4977 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4978 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4979 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4980 // Ivar declared in @implementation never belongs to the implementation. 4981 // Only it is in implementation's lexical context. 4982 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4983 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4984 } 4985 } 4986 4987 if (Attr) 4988 ProcessDeclAttributeList(S, Record, Attr); 4989} 4990 4991EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4992 EnumConstantDecl *LastEnumConst, 4993 SourceLocation IdLoc, 4994 IdentifierInfo *Id, 4995 ExprArg val) { 4996 Expr *Val = (Expr *)val.get(); 4997 4998 llvm::APSInt EnumVal(32); 4999 QualType EltTy; 5000 if (Val && !Val->isTypeDependent()) { 5001 // Make sure to promote the operand type to int. 5002 UsualUnaryConversions(Val); 5003 if (Val != val.get()) { 5004 val.release(); 5005 val = Val; 5006 } 5007 5008 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5009 SourceLocation ExpLoc; 5010 if (!Val->isValueDependent() && 5011 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5012 Val = 0; 5013 } else { 5014 EltTy = Val->getType(); 5015 } 5016 } 5017 5018 if (!Val) { 5019 if (LastEnumConst) { 5020 // Assign the last value + 1. 5021 EnumVal = LastEnumConst->getInitVal(); 5022 ++EnumVal; 5023 5024 // Check for overflow on increment. 5025 if (EnumVal < LastEnumConst->getInitVal()) 5026 Diag(IdLoc, diag::warn_enum_value_overflow); 5027 5028 EltTy = LastEnumConst->getType(); 5029 } else { 5030 // First value, set to zero. 5031 EltTy = Context.IntTy; 5032 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5033 } 5034 } 5035 5036 val.release(); 5037 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5038 Val, EnumVal); 5039} 5040 5041 5042Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5043 DeclPtrTy lastEnumConst, 5044 SourceLocation IdLoc, 5045 IdentifierInfo *Id, 5046 SourceLocation EqualLoc, ExprTy *val) { 5047 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5048 EnumConstantDecl *LastEnumConst = 5049 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5050 Expr *Val = static_cast<Expr*>(val); 5051 5052 // The scope passed in may not be a decl scope. Zip up the scope tree until 5053 // we find one that is. 5054 S = getNonFieldDeclScope(S); 5055 5056 // Verify that there isn't already something declared with this name in this 5057 // scope. 5058 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5059 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5060 // Maybe we will complain about the shadowed template parameter. 5061 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5062 // Just pretend that we didn't see the previous declaration. 5063 PrevDecl = 0; 5064 } 5065 5066 if (PrevDecl) { 5067 // When in C++, we may get a TagDecl with the same name; in this case the 5068 // enum constant will 'hide' the tag. 5069 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5070 "Received TagDecl when not in C++!"); 5071 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5072 if (isa<EnumConstantDecl>(PrevDecl)) 5073 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5074 else 5075 Diag(IdLoc, diag::err_redefinition) << Id; 5076 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5077 if (Val) Val->Destroy(Context); 5078 return DeclPtrTy(); 5079 } 5080 } 5081 5082 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5083 IdLoc, Id, Owned(Val)); 5084 5085 // Register this decl in the current scope stack. 5086 if (New) 5087 PushOnScopeChains(New, S); 5088 5089 return DeclPtrTy::make(New); 5090} 5091 5092void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5093 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5094 DeclPtrTy *Elements, unsigned NumElements, 5095 Scope *S, AttributeList *Attr) { 5096 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5097 QualType EnumType = Context.getTypeDeclType(Enum); 5098 5099 if (Attr) 5100 ProcessDeclAttributeList(S, Enum, Attr); 5101 5102 // TODO: If the result value doesn't fit in an int, it must be a long or long 5103 // long value. ISO C does not support this, but GCC does as an extension, 5104 // emit a warning. 5105 unsigned IntWidth = Context.Target.getIntWidth(); 5106 unsigned CharWidth = Context.Target.getCharWidth(); 5107 unsigned ShortWidth = Context.Target.getShortWidth(); 5108 5109 // Verify that all the values are okay, compute the size of the values, and 5110 // reverse the list. 5111 unsigned NumNegativeBits = 0; 5112 unsigned NumPositiveBits = 0; 5113 5114 // Keep track of whether all elements have type int. 5115 bool AllElementsInt = true; 5116 5117 for (unsigned i = 0; i != NumElements; ++i) { 5118 EnumConstantDecl *ECD = 5119 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5120 if (!ECD) continue; // Already issued a diagnostic. 5121 5122 // If the enum value doesn't fit in an int, emit an extension warning. 5123 const llvm::APSInt &InitVal = ECD->getInitVal(); 5124 assert(InitVal.getBitWidth() >= IntWidth && 5125 "Should have promoted value to int"); 5126 if (InitVal.getBitWidth() > IntWidth) { 5127 llvm::APSInt V(InitVal); 5128 V.trunc(IntWidth); 5129 V.extend(InitVal.getBitWidth()); 5130 if (V != InitVal) 5131 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5132 << InitVal.toString(10); 5133 } 5134 5135 // Keep track of the size of positive and negative values. 5136 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5137 NumPositiveBits = std::max(NumPositiveBits, 5138 (unsigned)InitVal.getActiveBits()); 5139 else 5140 NumNegativeBits = std::max(NumNegativeBits, 5141 (unsigned)InitVal.getMinSignedBits()); 5142 5143 // Keep track of whether every enum element has type int (very commmon). 5144 if (AllElementsInt) 5145 AllElementsInt = ECD->getType() == Context.IntTy; 5146 } 5147 5148 // Figure out the type that should be used for this enum. 5149 // FIXME: Support -fshort-enums. 5150 QualType BestType; 5151 unsigned BestWidth; 5152 5153 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5154 5155 if (NumNegativeBits) { 5156 // If there is a negative value, figure out the smallest integer type (of 5157 // int/long/longlong) that fits. 5158 // If it's packed, check also if it fits a char or a short. 5159 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5160 BestType = Context.SignedCharTy; 5161 BestWidth = CharWidth; 5162 } else if (Packed && NumNegativeBits <= ShortWidth && 5163 NumPositiveBits < ShortWidth) { 5164 BestType = Context.ShortTy; 5165 BestWidth = ShortWidth; 5166 } 5167 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5168 BestType = Context.IntTy; 5169 BestWidth = IntWidth; 5170 } else { 5171 BestWidth = Context.Target.getLongWidth(); 5172 5173 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5174 BestType = Context.LongTy; 5175 else { 5176 BestWidth = Context.Target.getLongLongWidth(); 5177 5178 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5179 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5180 BestType = Context.LongLongTy; 5181 } 5182 } 5183 } else { 5184 // If there is no negative value, figure out which of uint, ulong, ulonglong 5185 // fits. 5186 // If it's packed, check also if it fits a char or a short. 5187 if (Packed && NumPositiveBits <= CharWidth) { 5188 BestType = Context.UnsignedCharTy; 5189 BestWidth = CharWidth; 5190 } else if (Packed && NumPositiveBits <= ShortWidth) { 5191 BestType = Context.UnsignedShortTy; 5192 BestWidth = ShortWidth; 5193 } 5194 else if (NumPositiveBits <= IntWidth) { 5195 BestType = Context.UnsignedIntTy; 5196 BestWidth = IntWidth; 5197 } else if (NumPositiveBits <= 5198 (BestWidth = Context.Target.getLongWidth())) { 5199 BestType = Context.UnsignedLongTy; 5200 } else { 5201 BestWidth = Context.Target.getLongLongWidth(); 5202 assert(NumPositiveBits <= BestWidth && 5203 "How could an initializer get larger than ULL?"); 5204 BestType = Context.UnsignedLongLongTy; 5205 } 5206 } 5207 5208 // Loop over all of the enumerator constants, changing their types to match 5209 // the type of the enum if needed. 5210 for (unsigned i = 0; i != NumElements; ++i) { 5211 EnumConstantDecl *ECD = 5212 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5213 if (!ECD) continue; // Already issued a diagnostic. 5214 5215 // Standard C says the enumerators have int type, but we allow, as an 5216 // extension, the enumerators to be larger than int size. If each 5217 // enumerator value fits in an int, type it as an int, otherwise type it the 5218 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5219 // that X has type 'int', not 'unsigned'. 5220 if (ECD->getType() == Context.IntTy) { 5221 // Make sure the init value is signed. 5222 llvm::APSInt IV = ECD->getInitVal(); 5223 IV.setIsSigned(true); 5224 ECD->setInitVal(IV); 5225 5226 if (getLangOptions().CPlusPlus) 5227 // C++ [dcl.enum]p4: Following the closing brace of an 5228 // enum-specifier, each enumerator has the type of its 5229 // enumeration. 5230 ECD->setType(EnumType); 5231 continue; // Already int type. 5232 } 5233 5234 // Determine whether the value fits into an int. 5235 llvm::APSInt InitVal = ECD->getInitVal(); 5236 bool FitsInInt; 5237 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5238 FitsInInt = InitVal.getActiveBits() < IntWidth; 5239 else 5240 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5241 5242 // If it fits into an integer type, force it. Otherwise force it to match 5243 // the enum decl type. 5244 QualType NewTy; 5245 unsigned NewWidth; 5246 bool NewSign; 5247 if (FitsInInt) { 5248 NewTy = Context.IntTy; 5249 NewWidth = IntWidth; 5250 NewSign = true; 5251 } else if (ECD->getType() == BestType) { 5252 // Already the right type! 5253 if (getLangOptions().CPlusPlus) 5254 // C++ [dcl.enum]p4: Following the closing brace of an 5255 // enum-specifier, each enumerator has the type of its 5256 // enumeration. 5257 ECD->setType(EnumType); 5258 continue; 5259 } else { 5260 NewTy = BestType; 5261 NewWidth = BestWidth; 5262 NewSign = BestType->isSignedIntegerType(); 5263 } 5264 5265 // Adjust the APSInt value. 5266 InitVal.extOrTrunc(NewWidth); 5267 InitVal.setIsSigned(NewSign); 5268 ECD->setInitVal(InitVal); 5269 5270 // Adjust the Expr initializer and type. 5271 if (ECD->getInitExpr()) 5272 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5273 CastExpr::CK_Unknown, 5274 ECD->getInitExpr(), 5275 /*isLvalue=*/false)); 5276 if (getLangOptions().CPlusPlus) 5277 // C++ [dcl.enum]p4: Following the closing brace of an 5278 // enum-specifier, each enumerator has the type of its 5279 // enumeration. 5280 ECD->setType(EnumType); 5281 else 5282 ECD->setType(NewTy); 5283 } 5284 5285 Enum->completeDefinition(Context, BestType); 5286} 5287 5288Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5289 ExprArg expr) { 5290 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5291 5292 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5293 Loc, AsmString); 5294 CurContext->addDecl(New); 5295 return DeclPtrTy::make(New); 5296} 5297 5298void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5299 SourceLocation PragmaLoc, 5300 SourceLocation NameLoc) { 5301 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5302 5303 if (PrevDecl) { 5304 PrevDecl->addAttr(::new (Context) WeakAttr()); 5305 } else { 5306 (void)WeakUndeclaredIdentifiers.insert( 5307 std::pair<IdentifierInfo*,WeakInfo> 5308 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5309 } 5310} 5311 5312void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5313 IdentifierInfo* AliasName, 5314 SourceLocation PragmaLoc, 5315 SourceLocation NameLoc, 5316 SourceLocation AliasNameLoc) { 5317 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5318 WeakInfo W = WeakInfo(Name, NameLoc); 5319 5320 if (PrevDecl) { 5321 if (!PrevDecl->hasAttr<AliasAttr>()) 5322 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5323 DeclApplyPragmaWeak(TUScope, ND, W); 5324 } else { 5325 (void)WeakUndeclaredIdentifiers.insert( 5326 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5327 } 5328} 5329