SemaDecl.cpp revision 6fb0aee4f9dc261bbec72e1283ad8dc0557a6d96
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/DeclObjC.h" 20#include "clang/AST/DeclTemplate.h" 21#include "clang/AST/ExprCXX.h" 22#include "clang/AST/StmtCXX.h" 23#include "clang/Parse/DeclSpec.h" 24#include "clang/Basic/TargetInfo.h" 25#include "clang/Basic/SourceManager.h" 26// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 27#include "clang/Lex/Preprocessor.h" 28#include "clang/Lex/HeaderSearch.h" 29#include "llvm/ADT/SmallSet.h" 30#include "llvm/ADT/STLExtras.h" 31#include <algorithm> 32#include <functional> 33using namespace clang; 34 35/// getDeclName - Return a pretty name for the specified decl if possible, or 36/// an empty string if not. This is used for pretty crash reporting. 37std::string Sema::getDeclName(DeclPtrTy d) { 38 Decl *D = d.getAs<Decl>(); 39 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 40 return DN->getQualifiedNameAsString(); 41 return ""; 42} 43 44Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 45 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 46} 47 48/// \brief If the identifier refers to a type name within this scope, 49/// return the declaration of that type. 50/// 51/// This routine performs ordinary name lookup of the identifier II 52/// within the given scope, with optional C++ scope specifier SS, to 53/// determine whether the name refers to a type. If so, returns an 54/// opaque pointer (actually a QualType) corresponding to that 55/// type. Otherwise, returns NULL. 56/// 57/// If name lookup results in an ambiguity, this routine will complain 58/// and then return NULL. 59Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 60 Scope *S, const CXXScopeSpec *SS) { 61 // C++ [temp.res]p3: 62 // A qualified-id that refers to a type and in which the 63 // nested-name-specifier depends on a template-parameter (14.6.2) 64 // shall be prefixed by the keyword typename to indicate that the 65 // qualified-id denotes a type, forming an 66 // elaborated-type-specifier (7.1.5.3). 67 // 68 // We therefore do not perform any name lookup if the result would 69 // refer to a member of an unknown specialization. 70 if (SS && isUnknownSpecialization(*SS)) 71 return 0; 72 73 LookupResult Result 74 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 75 76 NamedDecl *IIDecl = 0; 77 switch (Result.getKind()) { 78 case LookupResult::NotFound: 79 case LookupResult::FoundOverloaded: 80 return 0; 81 82 case LookupResult::AmbiguousBaseSubobjectTypes: 83 case LookupResult::AmbiguousBaseSubobjects: 84 case LookupResult::AmbiguousReference: { 85 // Look to see if we have a type anywhere in the list of results. 86 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 87 Res != ResEnd; ++Res) { 88 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 89 if (!IIDecl || 90 (*Res)->getLocation().getRawEncoding() < 91 IIDecl->getLocation().getRawEncoding()) 92 IIDecl = *Res; 93 } 94 } 95 96 if (!IIDecl) { 97 // None of the entities we found is a type, so there is no way 98 // to even assume that the result is a type. In this case, don't 99 // complain about the ambiguity. The parser will either try to 100 // perform this lookup again (e.g., as an object name), which 101 // will produce the ambiguity, or will complain that it expected 102 // a type name. 103 Result.Destroy(); 104 return 0; 105 } 106 107 // We found a type within the ambiguous lookup; diagnose the 108 // ambiguity and then return that type. This might be the right 109 // answer, or it might not be, but it suppresses any attempt to 110 // perform the name lookup again. 111 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 112 break; 113 } 114 115 case LookupResult::Found: 116 IIDecl = Result.getAsDecl(); 117 break; 118 } 119 120 if (IIDecl) { 121 QualType T; 122 123 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 124 // Check whether we can use this type 125 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 126 127 if (getLangOptions().CPlusPlus) { 128 // C++ [temp.local]p2: 129 // Within the scope of a class template specialization or 130 // partial specialization, when the injected-class-name is 131 // not followed by a <, it is equivalent to the 132 // injected-class-name followed by the template-argument s 133 // of the class template specialization or partial 134 // specialization enclosed in <>. 135 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 136 if (RD->isInjectedClassName()) 137 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 138 T = Template->getInjectedClassNameType(Context); 139 } 140 141 if (T.isNull()) 142 T = Context.getTypeDeclType(TD); 143 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 144 // Check whether we can use this interface. 145 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 146 147 T = Context.getObjCInterfaceType(IDecl); 148 } else 149 return 0; 150 151 if (SS) 152 T = getQualifiedNameType(*SS, T); 153 154 return T.getAsOpaquePtr(); 155 } 156 157 return 0; 158} 159 160/// isTagName() - This method is called *for error recovery purposes only* 161/// to determine if the specified name is a valid tag name ("struct foo"). If 162/// so, this returns the TST for the tag corresponding to it (TST_enum, 163/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 164/// where the user forgot to specify the tag. 165DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 166 // Do a tag name lookup in this scope. 167 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 168 if (R.getKind() == LookupResult::Found) 169 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 170 switch (TD->getTagKind()) { 171 case TagDecl::TK_struct: return DeclSpec::TST_struct; 172 case TagDecl::TK_union: return DeclSpec::TST_union; 173 case TagDecl::TK_class: return DeclSpec::TST_class; 174 case TagDecl::TK_enum: return DeclSpec::TST_enum; 175 } 176 } 177 178 return DeclSpec::TST_unspecified; 179} 180 181 182 183DeclContext *Sema::getContainingDC(DeclContext *DC) { 184 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 185 // A C++ out-of-line method will return to the file declaration context. 186 if (MD->isOutOfLine()) 187 return MD->getLexicalDeclContext(); 188 189 // A C++ inline method is parsed *after* the topmost class it was declared 190 // in is fully parsed (it's "complete"). 191 // The parsing of a C++ inline method happens at the declaration context of 192 // the topmost (non-nested) class it is lexically declared in. 193 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 194 DC = MD->getParent(); 195 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 196 DC = RD; 197 198 // Return the declaration context of the topmost class the inline method is 199 // declared in. 200 return DC; 201 } 202 203 if (isa<ObjCMethodDecl>(DC)) 204 return Context.getTranslationUnitDecl(); 205 206 return DC->getLexicalParent(); 207} 208 209void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 210 assert(getContainingDC(DC) == CurContext && 211 "The next DeclContext should be lexically contained in the current one."); 212 CurContext = DC; 213 S->setEntity(DC); 214} 215 216void Sema::PopDeclContext() { 217 assert(CurContext && "DeclContext imbalance!"); 218 219 CurContext = getContainingDC(CurContext); 220} 221 222/// EnterDeclaratorContext - Used when we must lookup names in the context 223/// of a declarator's nested name specifier. 224void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 225 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 226 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 227 CurContext = DC; 228 assert(CurContext && "No context?"); 229 S->setEntity(CurContext); 230} 231 232void Sema::ExitDeclaratorContext(Scope *S) { 233 S->setEntity(PreDeclaratorDC); 234 PreDeclaratorDC = 0; 235 236 // Reset CurContext to the nearest enclosing context. 237 while (!S->getEntity() && S->getParent()) 238 S = S->getParent(); 239 CurContext = static_cast<DeclContext*>(S->getEntity()); 240 assert(CurContext && "No context?"); 241} 242 243/// \brief Determine whether we allow overloading of the function 244/// PrevDecl with another declaration. 245/// 246/// This routine determines whether overloading is possible, not 247/// whether some new function is actually an overload. It will return 248/// true in C++ (where we can always provide overloads) or, as an 249/// extension, in C when the previous function is already an 250/// overloaded function declaration or has the "overloadable" 251/// attribute. 252static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 253 if (Context.getLangOptions().CPlusPlus) 254 return true; 255 256 if (isa<OverloadedFunctionDecl>(PrevDecl)) 257 return true; 258 259 return PrevDecl->getAttr<OverloadableAttr>() != 0; 260} 261 262/// Add this decl to the scope shadowed decl chains. 263void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 264 // Move up the scope chain until we find the nearest enclosing 265 // non-transparent context. The declaration will be introduced into this 266 // scope. 267 while (S->getEntity() && 268 ((DeclContext *)S->getEntity())->isTransparentContext()) 269 S = S->getParent(); 270 271 S->AddDecl(DeclPtrTy::make(D)); 272 273 // Add scoped declarations into their context, so that they can be 274 // found later. Declarations without a context won't be inserted 275 // into any context. 276 CurContext->addDecl(Context, D); 277 278 // C++ [basic.scope]p4: 279 // -- exactly one declaration shall declare a class name or 280 // enumeration name that is not a typedef name and the other 281 // declarations shall all refer to the same object or 282 // enumerator, or all refer to functions and function templates; 283 // in this case the class name or enumeration name is hidden. 284 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 285 // We are pushing the name of a tag (enum or class). 286 if (CurContext->getLookupContext() 287 == TD->getDeclContext()->getLookupContext()) { 288 // We're pushing the tag into the current context, which might 289 // require some reshuffling in the identifier resolver. 290 IdentifierResolver::iterator 291 I = IdResolver.begin(TD->getDeclName()), 292 IEnd = IdResolver.end(); 293 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 294 NamedDecl *PrevDecl = *I; 295 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 296 PrevDecl = *I, ++I) { 297 if (TD->declarationReplaces(*I)) { 298 // This is a redeclaration. Remove it from the chain and 299 // break out, so that we'll add in the shadowed 300 // declaration. 301 S->RemoveDecl(DeclPtrTy::make(*I)); 302 if (PrevDecl == *I) { 303 IdResolver.RemoveDecl(*I); 304 IdResolver.AddDecl(TD); 305 return; 306 } else { 307 IdResolver.RemoveDecl(*I); 308 break; 309 } 310 } 311 } 312 313 // There is already a declaration with the same name in the same 314 // scope, which is not a tag declaration. It must be found 315 // before we find the new declaration, so insert the new 316 // declaration at the end of the chain. 317 IdResolver.AddShadowedDecl(TD, PrevDecl); 318 319 return; 320 } 321 } 322 } else if ((isa<FunctionDecl>(D) && 323 AllowOverloadingOfFunction(D, Context)) || 324 isa<FunctionTemplateDecl>(D)) { 325 // We are pushing the name of a function or function template, 326 // which might be an overloaded name. 327 IdentifierResolver::iterator Redecl 328 = std::find_if(IdResolver.begin(D->getDeclName()), 329 IdResolver.end(), 330 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 331 D)); 332 if (Redecl != IdResolver.end() && 333 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 334 // There is already a declaration of a function on our 335 // IdResolver chain. Replace it with this declaration. 336 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 337 IdResolver.RemoveDecl(*Redecl); 338 } 339 } else if (isa<ObjCInterfaceDecl>(D)) { 340 // We're pushing an Objective-C interface into the current 341 // context. If there is already an alias declaration, remove it first. 342 for (IdentifierResolver::iterator 343 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 344 I != IEnd; ++I) { 345 if (isa<ObjCCompatibleAliasDecl>(*I)) { 346 S->RemoveDecl(DeclPtrTy::make(*I)); 347 IdResolver.RemoveDecl(*I); 348 break; 349 } 350 } 351 } 352 353 IdResolver.AddDecl(D); 354} 355 356void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 357 if (S->decl_empty()) return; 358 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 359 "Scope shouldn't contain decls!"); 360 361 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 362 I != E; ++I) { 363 Decl *TmpD = (*I).getAs<Decl>(); 364 assert(TmpD && "This decl didn't get pushed??"); 365 366 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 367 NamedDecl *D = cast<NamedDecl>(TmpD); 368 369 if (!D->getDeclName()) continue; 370 371 // Remove this name from our lexical scope. 372 IdResolver.RemoveDecl(D); 373 } 374} 375 376/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 377/// return 0 if one not found. 378ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 379 // The third "scope" argument is 0 since we aren't enabling lazy built-in 380 // creation from this context. 381 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 382 383 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 384} 385 386/// getNonFieldDeclScope - Retrieves the innermost scope, starting 387/// from S, where a non-field would be declared. This routine copes 388/// with the difference between C and C++ scoping rules in structs and 389/// unions. For example, the following code is well-formed in C but 390/// ill-formed in C++: 391/// @code 392/// struct S6 { 393/// enum { BAR } e; 394/// }; 395/// 396/// void test_S6() { 397/// struct S6 a; 398/// a.e = BAR; 399/// } 400/// @endcode 401/// For the declaration of BAR, this routine will return a different 402/// scope. The scope S will be the scope of the unnamed enumeration 403/// within S6. In C++, this routine will return the scope associated 404/// with S6, because the enumeration's scope is a transparent 405/// context but structures can contain non-field names. In C, this 406/// routine will return the translation unit scope, since the 407/// enumeration's scope is a transparent context and structures cannot 408/// contain non-field names. 409Scope *Sema::getNonFieldDeclScope(Scope *S) { 410 while (((S->getFlags() & Scope::DeclScope) == 0) || 411 (S->getEntity() && 412 ((DeclContext *)S->getEntity())->isTransparentContext()) || 413 (S->isClassScope() && !getLangOptions().CPlusPlus)) 414 S = S->getParent(); 415 return S; 416} 417 418void Sema::InitBuiltinVaListType() { 419 if (!Context.getBuiltinVaListType().isNull()) 420 return; 421 422 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 423 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 424 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 425 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 426} 427 428/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 429/// file scope. lazily create a decl for it. ForRedeclaration is true 430/// if we're creating this built-in in anticipation of redeclaring the 431/// built-in. 432NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 433 Scope *S, bool ForRedeclaration, 434 SourceLocation Loc) { 435 Builtin::ID BID = (Builtin::ID)bid; 436 437 if (Context.BuiltinInfo.hasVAListUse(BID)) 438 InitBuiltinVaListType(); 439 440 ASTContext::GetBuiltinTypeError Error; 441 QualType R = Context.GetBuiltinType(BID, Error); 442 switch (Error) { 443 case ASTContext::GE_None: 444 // Okay 445 break; 446 447 case ASTContext::GE_Missing_FILE: 448 if (ForRedeclaration) 449 Diag(Loc, diag::err_implicit_decl_requires_stdio) 450 << Context.BuiltinInfo.GetName(BID); 451 return 0; 452 } 453 454 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 455 Diag(Loc, diag::ext_implicit_lib_function_decl) 456 << Context.BuiltinInfo.GetName(BID) 457 << R; 458 if (Context.BuiltinInfo.getHeaderName(BID) && 459 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 460 != Diagnostic::Ignored) 461 Diag(Loc, diag::note_please_include_header) 462 << Context.BuiltinInfo.getHeaderName(BID) 463 << Context.BuiltinInfo.GetName(BID); 464 } 465 466 FunctionDecl *New = FunctionDecl::Create(Context, 467 Context.getTranslationUnitDecl(), 468 Loc, II, R, 469 FunctionDecl::Extern, false, 470 /*hasPrototype=*/true); 471 New->setImplicit(); 472 473 // Create Decl objects for each parameter, adding them to the 474 // FunctionDecl. 475 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 476 llvm::SmallVector<ParmVarDecl*, 16> Params; 477 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 478 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 479 FT->getArgType(i), VarDecl::None, 0)); 480 New->setParams(Context, Params.data(), Params.size()); 481 } 482 483 AddKnownFunctionAttributes(New); 484 485 // TUScope is the translation-unit scope to insert this function into. 486 // FIXME: This is hideous. We need to teach PushOnScopeChains to 487 // relate Scopes to DeclContexts, and probably eliminate CurContext 488 // entirely, but we're not there yet. 489 DeclContext *SavedContext = CurContext; 490 CurContext = Context.getTranslationUnitDecl(); 491 PushOnScopeChains(New, TUScope); 492 CurContext = SavedContext; 493 return New; 494} 495 496/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 497/// everything from the standard library is defined. 498NamespaceDecl *Sema::GetStdNamespace() { 499 if (!StdNamespace) { 500 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 501 DeclContext *Global = Context.getTranslationUnitDecl(); 502 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 503 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 504 } 505 return StdNamespace; 506} 507 508/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 509/// same name and scope as a previous declaration 'Old'. Figure out 510/// how to resolve this situation, merging decls or emitting 511/// diagnostics as appropriate. If there was an error, set New to be invalid. 512/// 513void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 514 // If either decl is known invalid already, set the new one to be invalid and 515 // don't bother doing any merging checks. 516 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 517 return New->setInvalidDecl(); 518 519 bool objc_types = false; 520 521 // Allow multiple definitions for ObjC built-in typedefs. 522 // FIXME: Verify the underlying types are equivalent! 523 if (getLangOptions().ObjC1) { 524 const IdentifierInfo *TypeID = New->getIdentifier(); 525 switch (TypeID->getLength()) { 526 default: break; 527 case 2: 528 if (!TypeID->isStr("id")) 529 break; 530 Context.setObjCIdType(Context.getTypeDeclType(New)); 531 objc_types = true; 532 break; 533 case 5: 534 if (!TypeID->isStr("Class")) 535 break; 536 Context.setObjCClassType(Context.getTypeDeclType(New)); 537 return; 538 case 3: 539 if (!TypeID->isStr("SEL")) 540 break; 541 Context.setObjCSelType(Context.getTypeDeclType(New)); 542 return; 543 case 8: 544 if (!TypeID->isStr("Protocol")) 545 break; 546 Context.setObjCProtoType(New->getUnderlyingType()); 547 return; 548 } 549 // Fall through - the typedef name was not a builtin type. 550 } 551 // Verify the old decl was also a type. 552 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 553 if (!Old) { 554 Diag(New->getLocation(), diag::err_redefinition_different_kind) 555 << New->getDeclName(); 556 if (OldD->getLocation().isValid()) 557 Diag(OldD->getLocation(), diag::note_previous_definition); 558 return New->setInvalidDecl(); 559 } 560 561 // Determine the "old" type we'll use for checking and diagnostics. 562 QualType OldType; 563 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 564 OldType = OldTypedef->getUnderlyingType(); 565 else 566 OldType = Context.getTypeDeclType(Old); 567 568 // If the typedef types are not identical, reject them in all languages and 569 // with any extensions enabled. 570 571 if (OldType != New->getUnderlyingType() && 572 Context.getCanonicalType(OldType) != 573 Context.getCanonicalType(New->getUnderlyingType())) { 574 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 575 << New->getUnderlyingType() << OldType; 576 if (Old->getLocation().isValid()) 577 Diag(Old->getLocation(), diag::note_previous_definition); 578 return New->setInvalidDecl(); 579 } 580 581 if (objc_types || getLangOptions().Microsoft) 582 return; 583 584 // C++ [dcl.typedef]p2: 585 // In a given non-class scope, a typedef specifier can be used to 586 // redefine the name of any type declared in that scope to refer 587 // to the type to which it already refers. 588 if (getLangOptions().CPlusPlus) { 589 if (!isa<CXXRecordDecl>(CurContext)) 590 return; 591 Diag(New->getLocation(), diag::err_redefinition) 592 << New->getDeclName(); 593 Diag(Old->getLocation(), diag::note_previous_definition); 594 return New->setInvalidDecl(); 595 } 596 597 // If we have a redefinition of a typedef in C, emit a warning. This warning 598 // is normally mapped to an error, but can be controlled with 599 // -Wtypedef-redefinition. If either the original or the redefinition is 600 // in a system header, don't emit this for compatibility with GCC. 601 if (PP.getDiagnostics().getSuppressSystemWarnings() && 602 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 603 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 604 return; 605 606 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 607 << New->getDeclName(); 608 Diag(Old->getLocation(), diag::note_previous_definition); 609 return; 610} 611 612/// DeclhasAttr - returns true if decl Declaration already has the target 613/// attribute. 614static bool 615DeclHasAttr(const Decl *decl, const Attr *target) { 616 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 617 if (attr->getKind() == target->getKind()) 618 return true; 619 620 return false; 621} 622 623/// MergeAttributes - append attributes from the Old decl to the New one. 624static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 625 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 626 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 627 Attr *NewAttr = attr->clone(C); 628 NewAttr->setInherited(true); 629 New->addAttr(NewAttr); 630 } 631 } 632} 633 634/// Used in MergeFunctionDecl to keep track of function parameters in 635/// C. 636struct GNUCompatibleParamWarning { 637 ParmVarDecl *OldParm; 638 ParmVarDecl *NewParm; 639 QualType PromotedType; 640}; 641 642/// MergeFunctionDecl - We just parsed a function 'New' from 643/// declarator D which has the same name and scope as a previous 644/// declaration 'Old'. Figure out how to resolve this situation, 645/// merging decls or emitting diagnostics as appropriate. 646/// 647/// In C++, New and Old must be declarations that are not 648/// overloaded. Use IsOverload to determine whether New and Old are 649/// overloaded, and to select the Old declaration that New should be 650/// merged with. 651/// 652/// Returns true if there was an error, false otherwise. 653bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 654 assert(!isa<OverloadedFunctionDecl>(OldD) && 655 "Cannot merge with an overloaded function declaration"); 656 657 // Verify the old decl was also a function. 658 FunctionDecl *Old = 0; 659 if (FunctionTemplateDecl *OldFunctionTemplate 660 = dyn_cast<FunctionTemplateDecl>(OldD)) 661 Old = OldFunctionTemplate->getTemplatedDecl(); 662 else 663 Old = dyn_cast<FunctionDecl>(OldD); 664 if (!Old) { 665 Diag(New->getLocation(), diag::err_redefinition_different_kind) 666 << New->getDeclName(); 667 Diag(OldD->getLocation(), diag::note_previous_definition); 668 return true; 669 } 670 671 // Determine whether the previous declaration was a definition, 672 // implicit declaration, or a declaration. 673 diag::kind PrevDiag; 674 if (Old->isThisDeclarationADefinition()) 675 PrevDiag = diag::note_previous_definition; 676 else if (Old->isImplicit()) 677 PrevDiag = diag::note_previous_implicit_declaration; 678 else 679 PrevDiag = diag::note_previous_declaration; 680 681 QualType OldQType = Context.getCanonicalType(Old->getType()); 682 QualType NewQType = Context.getCanonicalType(New->getType()); 683 684 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 685 New->getStorageClass() == FunctionDecl::Static && 686 Old->getStorageClass() != FunctionDecl::Static) { 687 Diag(New->getLocation(), diag::err_static_non_static) 688 << New; 689 Diag(Old->getLocation(), PrevDiag); 690 return true; 691 } 692 693 if (getLangOptions().CPlusPlus) { 694 // (C++98 13.1p2): 695 // Certain function declarations cannot be overloaded: 696 // -- Function declarations that differ only in the return type 697 // cannot be overloaded. 698 QualType OldReturnType 699 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 700 QualType NewReturnType 701 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 702 if (OldReturnType != NewReturnType) { 703 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 704 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 705 return true; 706 } 707 708 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 709 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 710 if (OldMethod && NewMethod && 711 OldMethod->getLexicalDeclContext() == 712 NewMethod->getLexicalDeclContext()) { 713 // -- Member function declarations with the same name and the 714 // same parameter types cannot be overloaded if any of them 715 // is a static member function declaration. 716 if (OldMethod->isStatic() || NewMethod->isStatic()) { 717 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 718 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 719 return true; 720 } 721 722 // C++ [class.mem]p1: 723 // [...] A member shall not be declared twice in the 724 // member-specification, except that a nested class or member 725 // class template can be declared and then later defined. 726 unsigned NewDiag; 727 if (isa<CXXConstructorDecl>(OldMethod)) 728 NewDiag = diag::err_constructor_redeclared; 729 else if (isa<CXXDestructorDecl>(NewMethod)) 730 NewDiag = diag::err_destructor_redeclared; 731 else if (isa<CXXConversionDecl>(NewMethod)) 732 NewDiag = diag::err_conv_function_redeclared; 733 else 734 NewDiag = diag::err_member_redeclared; 735 736 Diag(New->getLocation(), NewDiag); 737 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 738 } 739 740 // (C++98 8.3.5p3): 741 // All declarations for a function shall agree exactly in both the 742 // return type and the parameter-type-list. 743 if (OldQType == NewQType) 744 return MergeCompatibleFunctionDecls(New, Old); 745 746 // Fall through for conflicting redeclarations and redefinitions. 747 } 748 749 // C: Function types need to be compatible, not identical. This handles 750 // duplicate function decls like "void f(int); void f(enum X);" properly. 751 if (!getLangOptions().CPlusPlus && 752 Context.typesAreCompatible(OldQType, NewQType)) { 753 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 754 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 755 const FunctionProtoType *OldProto = 0; 756 if (isa<FunctionNoProtoType>(NewFuncType) && 757 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 758 // The old declaration provided a function prototype, but the 759 // new declaration does not. Merge in the prototype. 760 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 761 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 762 OldProto->arg_type_end()); 763 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 764 ParamTypes.data(), ParamTypes.size(), 765 OldProto->isVariadic(), 766 OldProto->getTypeQuals()); 767 New->setType(NewQType); 768 New->setHasInheritedPrototype(); 769 770 // Synthesize a parameter for each argument type. 771 llvm::SmallVector<ParmVarDecl*, 16> Params; 772 for (FunctionProtoType::arg_type_iterator 773 ParamType = OldProto->arg_type_begin(), 774 ParamEnd = OldProto->arg_type_end(); 775 ParamType != ParamEnd; ++ParamType) { 776 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 777 SourceLocation(), 0, 778 *ParamType, VarDecl::None, 779 0); 780 Param->setImplicit(); 781 Params.push_back(Param); 782 } 783 784 New->setParams(Context, Params.data(), Params.size()); 785 } 786 787 return MergeCompatibleFunctionDecls(New, Old); 788 } 789 790 // GNU C permits a K&R definition to follow a prototype declaration 791 // if the declared types of the parameters in the K&R definition 792 // match the types in the prototype declaration, even when the 793 // promoted types of the parameters from the K&R definition differ 794 // from the types in the prototype. GCC then keeps the types from 795 // the prototype. 796 // 797 // If a variadic prototype is followed by a non-variadic K&R definition, 798 // the K&R definition becomes variadic. This is sort of an edge case, but 799 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 800 // C99 6.9.1p8. 801 if (!getLangOptions().CPlusPlus && 802 Old->hasPrototype() && !New->hasPrototype() && 803 New->getType()->getAsFunctionProtoType() && 804 Old->getNumParams() == New->getNumParams()) { 805 llvm::SmallVector<QualType, 16> ArgTypes; 806 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 807 const FunctionProtoType *OldProto 808 = Old->getType()->getAsFunctionProtoType(); 809 const FunctionProtoType *NewProto 810 = New->getType()->getAsFunctionProtoType(); 811 812 // Determine whether this is the GNU C extension. 813 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 814 NewProto->getResultType()); 815 bool LooseCompatible = !MergedReturn.isNull(); 816 for (unsigned Idx = 0, End = Old->getNumParams(); 817 LooseCompatible && Idx != End; ++Idx) { 818 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 819 ParmVarDecl *NewParm = New->getParamDecl(Idx); 820 if (Context.typesAreCompatible(OldParm->getType(), 821 NewProto->getArgType(Idx))) { 822 ArgTypes.push_back(NewParm->getType()); 823 } else if (Context.typesAreCompatible(OldParm->getType(), 824 NewParm->getType())) { 825 GNUCompatibleParamWarning Warn 826 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 827 Warnings.push_back(Warn); 828 ArgTypes.push_back(NewParm->getType()); 829 } else 830 LooseCompatible = false; 831 } 832 833 if (LooseCompatible) { 834 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 835 Diag(Warnings[Warn].NewParm->getLocation(), 836 diag::ext_param_promoted_not_compatible_with_prototype) 837 << Warnings[Warn].PromotedType 838 << Warnings[Warn].OldParm->getType(); 839 Diag(Warnings[Warn].OldParm->getLocation(), 840 diag::note_previous_declaration); 841 } 842 843 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 844 ArgTypes.size(), 845 OldProto->isVariadic(), 0)); 846 return MergeCompatibleFunctionDecls(New, Old); 847 } 848 849 // Fall through to diagnose conflicting types. 850 } 851 852 // A function that has already been declared has been redeclared or defined 853 // with a different type- show appropriate diagnostic 854 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 855 // The user has declared a builtin function with an incompatible 856 // signature. 857 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 858 // The function the user is redeclaring is a library-defined 859 // function like 'malloc' or 'printf'. Warn about the 860 // redeclaration, then pretend that we don't know about this 861 // library built-in. 862 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 863 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 864 << Old << Old->getType(); 865 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 866 Old->setInvalidDecl(); 867 return false; 868 } 869 870 PrevDiag = diag::note_previous_builtin_declaration; 871 } 872 873 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 874 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 875 return true; 876} 877 878/// \brief Completes the merge of two function declarations that are 879/// known to be compatible. 880/// 881/// This routine handles the merging of attributes and other 882/// properties of function declarations form the old declaration to 883/// the new declaration, once we know that New is in fact a 884/// redeclaration of Old. 885/// 886/// \returns false 887bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 888 // Merge the attributes 889 MergeAttributes(New, Old, Context); 890 891 // Merge the storage class. 892 if (Old->getStorageClass() != FunctionDecl::Extern) 893 New->setStorageClass(Old->getStorageClass()); 894 895 // Merge "inline" 896 if (Old->isInline()) 897 New->setInline(true); 898 899 // If this function declaration by itself qualifies as a C99 inline 900 // definition (C99 6.7.4p6), but the previous definition did not, 901 // then the function is not a C99 inline definition. 902 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 903 New->setC99InlineDefinition(false); 904 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 905 // Mark all preceding definitions as not being C99 inline definitions. 906 for (const FunctionDecl *Prev = Old; Prev; 907 Prev = Prev->getPreviousDeclaration()) 908 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 909 } 910 911 // Merge "pure" flag. 912 if (Old->isPure()) 913 New->setPure(); 914 915 // Merge the "deleted" flag. 916 if (Old->isDeleted()) 917 New->setDeleted(); 918 919 if (getLangOptions().CPlusPlus) 920 return MergeCXXFunctionDecl(New, Old); 921 922 return false; 923} 924 925/// MergeVarDecl - We just parsed a variable 'New' which has the same name 926/// and scope as a previous declaration 'Old'. Figure out how to resolve this 927/// situation, merging decls or emitting diagnostics as appropriate. 928/// 929/// Tentative definition rules (C99 6.9.2p2) are checked by 930/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 931/// definitions here, since the initializer hasn't been attached. 932/// 933void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 934 // If either decl is invalid, make sure the new one is marked invalid and 935 // don't do any other checking. 936 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 937 return New->setInvalidDecl(); 938 939 // Verify the old decl was also a variable. 940 VarDecl *Old = dyn_cast<VarDecl>(OldD); 941 if (!Old) { 942 Diag(New->getLocation(), diag::err_redefinition_different_kind) 943 << New->getDeclName(); 944 Diag(OldD->getLocation(), diag::note_previous_definition); 945 return New->setInvalidDecl(); 946 } 947 948 MergeAttributes(New, Old, Context); 949 950 // Merge the types 951 QualType MergedT; 952 if (getLangOptions().CPlusPlus) { 953 if (Context.hasSameType(New->getType(), Old->getType())) 954 MergedT = New->getType(); 955 } else { 956 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 957 } 958 if (MergedT.isNull()) { 959 Diag(New->getLocation(), diag::err_redefinition_different_type) 960 << New->getDeclName(); 961 Diag(Old->getLocation(), diag::note_previous_definition); 962 return New->setInvalidDecl(); 963 } 964 New->setType(MergedT); 965 966 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 967 if (New->getStorageClass() == VarDecl::Static && 968 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 969 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 970 Diag(Old->getLocation(), diag::note_previous_definition); 971 return New->setInvalidDecl(); 972 } 973 // C99 6.2.2p4: 974 // For an identifier declared with the storage-class specifier 975 // extern in a scope in which a prior declaration of that 976 // identifier is visible,23) if the prior declaration specifies 977 // internal or external linkage, the linkage of the identifier at 978 // the later declaration is the same as the linkage specified at 979 // the prior declaration. If no prior declaration is visible, or 980 // if the prior declaration specifies no linkage, then the 981 // identifier has external linkage. 982 if (New->hasExternalStorage() && Old->hasLinkage()) 983 /* Okay */; 984 else if (New->getStorageClass() != VarDecl::Static && 985 Old->getStorageClass() == VarDecl::Static) { 986 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 987 Diag(Old->getLocation(), diag::note_previous_definition); 988 return New->setInvalidDecl(); 989 } 990 991 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 992 993 // FIXME: The test for external storage here seems wrong? We still 994 // need to check for mismatches. 995 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 996 // Don't complain about out-of-line definitions of static members. 997 !(Old->getLexicalDeclContext()->isRecord() && 998 !New->getLexicalDeclContext()->isRecord())) { 999 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1000 Diag(Old->getLocation(), diag::note_previous_definition); 1001 return New->setInvalidDecl(); 1002 } 1003 1004 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1005 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1006 Diag(Old->getLocation(), diag::note_previous_definition); 1007 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1008 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1009 Diag(Old->getLocation(), diag::note_previous_definition); 1010 } 1011 1012 // Keep a chain of previous declarations. 1013 New->setPreviousDeclaration(Old); 1014} 1015 1016/// CheckParmsForFunctionDef - Check that the parameters of the given 1017/// function are appropriate for the definition of a function. This 1018/// takes care of any checks that cannot be performed on the 1019/// declaration itself, e.g., that the types of each of the function 1020/// parameters are complete. 1021bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1022 bool HasInvalidParm = false; 1023 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1024 ParmVarDecl *Param = FD->getParamDecl(p); 1025 1026 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1027 // function declarator that is part of a function definition of 1028 // that function shall not have incomplete type. 1029 // 1030 // This is also C++ [dcl.fct]p6. 1031 if (!Param->isInvalidDecl() && 1032 RequireCompleteType(Param->getLocation(), Param->getType(), 1033 diag::err_typecheck_decl_incomplete_type)) { 1034 Param->setInvalidDecl(); 1035 HasInvalidParm = true; 1036 } 1037 1038 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1039 // declaration of each parameter shall include an identifier. 1040 if (Param->getIdentifier() == 0 && 1041 !Param->isImplicit() && 1042 !getLangOptions().CPlusPlus) 1043 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1044 } 1045 1046 return HasInvalidParm; 1047} 1048 1049/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1050/// no declarator (e.g. "struct foo;") is parsed. 1051Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1052 // FIXME: Error on auto/register at file scope 1053 // FIXME: Error on inline/virtual/explicit 1054 // FIXME: Error on invalid restrict 1055 // FIXME: Warn on useless __thread 1056 // FIXME: Warn on useless const/volatile 1057 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1058 // FIXME: Warn on useless attributes 1059 TagDecl *Tag = 0; 1060 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1061 DS.getTypeSpecType() == DeclSpec::TST_struct || 1062 DS.getTypeSpecType() == DeclSpec::TST_union || 1063 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1064 if (!DS.getTypeRep()) // We probably had an error 1065 return DeclPtrTy(); 1066 1067 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1068 } 1069 1070 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1071 if (!Record->getDeclName() && Record->isDefinition() && 1072 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1073 if (getLangOptions().CPlusPlus || 1074 Record->getDeclContext()->isRecord()) 1075 return BuildAnonymousStructOrUnion(S, DS, Record); 1076 1077 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1078 << DS.getSourceRange(); 1079 } 1080 1081 // Microsoft allows unnamed struct/union fields. Don't complain 1082 // about them. 1083 // FIXME: Should we support Microsoft's extensions in this area? 1084 if (Record->getDeclName() && getLangOptions().Microsoft) 1085 return DeclPtrTy::make(Tag); 1086 } 1087 1088 if (!DS.isMissingDeclaratorOk() && 1089 DS.getTypeSpecType() != DeclSpec::TST_error) { 1090 // Warn about typedefs of enums without names, since this is an 1091 // extension in both Microsoft an GNU. 1092 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1093 Tag && isa<EnumDecl>(Tag)) { 1094 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1095 << DS.getSourceRange(); 1096 return DeclPtrTy::make(Tag); 1097 } 1098 1099 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1100 << DS.getSourceRange(); 1101 return DeclPtrTy(); 1102 } 1103 1104 return DeclPtrTy::make(Tag); 1105} 1106 1107/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1108/// anonymous struct or union AnonRecord into the owning context Owner 1109/// and scope S. This routine will be invoked just after we realize 1110/// that an unnamed union or struct is actually an anonymous union or 1111/// struct, e.g., 1112/// 1113/// @code 1114/// union { 1115/// int i; 1116/// float f; 1117/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1118/// // f into the surrounding scope.x 1119/// @endcode 1120/// 1121/// This routine is recursive, injecting the names of nested anonymous 1122/// structs/unions into the owning context and scope as well. 1123bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1124 RecordDecl *AnonRecord) { 1125 bool Invalid = false; 1126 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1127 FEnd = AnonRecord->field_end(Context); 1128 F != FEnd; ++F) { 1129 if ((*F)->getDeclName()) { 1130 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1131 LookupOrdinaryName, true); 1132 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1133 // C++ [class.union]p2: 1134 // The names of the members of an anonymous union shall be 1135 // distinct from the names of any other entity in the 1136 // scope in which the anonymous union is declared. 1137 unsigned diagKind 1138 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1139 : diag::err_anonymous_struct_member_redecl; 1140 Diag((*F)->getLocation(), diagKind) 1141 << (*F)->getDeclName(); 1142 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1143 Invalid = true; 1144 } else { 1145 // C++ [class.union]p2: 1146 // For the purpose of name lookup, after the anonymous union 1147 // definition, the members of the anonymous union are 1148 // considered to have been defined in the scope in which the 1149 // anonymous union is declared. 1150 Owner->makeDeclVisibleInContext(Context, *F); 1151 S->AddDecl(DeclPtrTy::make(*F)); 1152 IdResolver.AddDecl(*F); 1153 } 1154 } else if (const RecordType *InnerRecordType 1155 = (*F)->getType()->getAsRecordType()) { 1156 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1157 if (InnerRecord->isAnonymousStructOrUnion()) 1158 Invalid = Invalid || 1159 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1160 } 1161 } 1162 1163 return Invalid; 1164} 1165 1166/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1167/// anonymous structure or union. Anonymous unions are a C++ feature 1168/// (C++ [class.union]) and a GNU C extension; anonymous structures 1169/// are a GNU C and GNU C++ extension. 1170Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1171 RecordDecl *Record) { 1172 DeclContext *Owner = Record->getDeclContext(); 1173 1174 // Diagnose whether this anonymous struct/union is an extension. 1175 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1176 Diag(Record->getLocation(), diag::ext_anonymous_union); 1177 else if (!Record->isUnion()) 1178 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1179 1180 // C and C++ require different kinds of checks for anonymous 1181 // structs/unions. 1182 bool Invalid = false; 1183 if (getLangOptions().CPlusPlus) { 1184 const char* PrevSpec = 0; 1185 // C++ [class.union]p3: 1186 // Anonymous unions declared in a named namespace or in the 1187 // global namespace shall be declared static. 1188 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1189 (isa<TranslationUnitDecl>(Owner) || 1190 (isa<NamespaceDecl>(Owner) && 1191 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1192 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1193 Invalid = true; 1194 1195 // Recover by adding 'static'. 1196 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1197 } 1198 // C++ [class.union]p3: 1199 // A storage class is not allowed in a declaration of an 1200 // anonymous union in a class scope. 1201 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1202 isa<RecordDecl>(Owner)) { 1203 Diag(DS.getStorageClassSpecLoc(), 1204 diag::err_anonymous_union_with_storage_spec); 1205 Invalid = true; 1206 1207 // Recover by removing the storage specifier. 1208 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1209 PrevSpec); 1210 } 1211 1212 // C++ [class.union]p2: 1213 // The member-specification of an anonymous union shall only 1214 // define non-static data members. [Note: nested types and 1215 // functions cannot be declared within an anonymous union. ] 1216 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1217 MemEnd = Record->decls_end(Context); 1218 Mem != MemEnd; ++Mem) { 1219 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1220 // C++ [class.union]p3: 1221 // An anonymous union shall not have private or protected 1222 // members (clause 11). 1223 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1224 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1225 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1226 Invalid = true; 1227 } 1228 } else if ((*Mem)->isImplicit()) { 1229 // Any implicit members are fine. 1230 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1231 // This is a type that showed up in an 1232 // elaborated-type-specifier inside the anonymous struct or 1233 // union, but which actually declares a type outside of the 1234 // anonymous struct or union. It's okay. 1235 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1236 if (!MemRecord->isAnonymousStructOrUnion() && 1237 MemRecord->getDeclName()) { 1238 // This is a nested type declaration. 1239 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1240 << (int)Record->isUnion(); 1241 Invalid = true; 1242 } 1243 } else { 1244 // We have something that isn't a non-static data 1245 // member. Complain about it. 1246 unsigned DK = diag::err_anonymous_record_bad_member; 1247 if (isa<TypeDecl>(*Mem)) 1248 DK = diag::err_anonymous_record_with_type; 1249 else if (isa<FunctionDecl>(*Mem)) 1250 DK = diag::err_anonymous_record_with_function; 1251 else if (isa<VarDecl>(*Mem)) 1252 DK = diag::err_anonymous_record_with_static; 1253 Diag((*Mem)->getLocation(), DK) 1254 << (int)Record->isUnion(); 1255 Invalid = true; 1256 } 1257 } 1258 } 1259 1260 if (!Record->isUnion() && !Owner->isRecord()) { 1261 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1262 << (int)getLangOptions().CPlusPlus; 1263 Invalid = true; 1264 } 1265 1266 // Create a declaration for this anonymous struct/union. 1267 NamedDecl *Anon = 0; 1268 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1269 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1270 /*IdentifierInfo=*/0, 1271 Context.getTypeDeclType(Record), 1272 /*BitWidth=*/0, /*Mutable=*/false); 1273 Anon->setAccess(AS_public); 1274 if (getLangOptions().CPlusPlus) 1275 FieldCollector->Add(cast<FieldDecl>(Anon)); 1276 } else { 1277 VarDecl::StorageClass SC; 1278 switch (DS.getStorageClassSpec()) { 1279 default: assert(0 && "Unknown storage class!"); 1280 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1281 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1282 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1283 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1284 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1285 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1286 case DeclSpec::SCS_mutable: 1287 // mutable can only appear on non-static class members, so it's always 1288 // an error here 1289 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1290 Invalid = true; 1291 SC = VarDecl::None; 1292 break; 1293 } 1294 1295 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1296 /*IdentifierInfo=*/0, 1297 Context.getTypeDeclType(Record), 1298 SC, DS.getSourceRange().getBegin()); 1299 } 1300 Anon->setImplicit(); 1301 1302 // Add the anonymous struct/union object to the current 1303 // context. We'll be referencing this object when we refer to one of 1304 // its members. 1305 Owner->addDecl(Context, Anon); 1306 1307 // Inject the members of the anonymous struct/union into the owning 1308 // context and into the identifier resolver chain for name lookup 1309 // purposes. 1310 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1311 Invalid = true; 1312 1313 // Mark this as an anonymous struct/union type. Note that we do not 1314 // do this until after we have already checked and injected the 1315 // members of this anonymous struct/union type, because otherwise 1316 // the members could be injected twice: once by DeclContext when it 1317 // builds its lookup table, and once by 1318 // InjectAnonymousStructOrUnionMembers. 1319 Record->setAnonymousStructOrUnion(true); 1320 1321 if (Invalid) 1322 Anon->setInvalidDecl(); 1323 1324 return DeclPtrTy::make(Anon); 1325} 1326 1327 1328/// GetNameForDeclarator - Determine the full declaration name for the 1329/// given Declarator. 1330DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1331 switch (D.getKind()) { 1332 case Declarator::DK_Abstract: 1333 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1334 return DeclarationName(); 1335 1336 case Declarator::DK_Normal: 1337 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1338 return DeclarationName(D.getIdentifier()); 1339 1340 case Declarator::DK_Constructor: { 1341 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1342 Ty = Context.getCanonicalType(Ty); 1343 return Context.DeclarationNames.getCXXConstructorName(Ty); 1344 } 1345 1346 case Declarator::DK_Destructor: { 1347 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1348 Ty = Context.getCanonicalType(Ty); 1349 return Context.DeclarationNames.getCXXDestructorName(Ty); 1350 } 1351 1352 case Declarator::DK_Conversion: { 1353 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1354 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1355 Ty = Context.getCanonicalType(Ty); 1356 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1357 } 1358 1359 case Declarator::DK_Operator: 1360 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1361 return Context.DeclarationNames.getCXXOperatorName( 1362 D.getOverloadedOperator()); 1363 } 1364 1365 assert(false && "Unknown name kind"); 1366 return DeclarationName(); 1367} 1368 1369/// isNearlyMatchingFunction - Determine whether the C++ functions 1370/// Declaration and Definition are "nearly" matching. This heuristic 1371/// is used to improve diagnostics in the case where an out-of-line 1372/// function definition doesn't match any declaration within 1373/// the class or namespace. 1374static bool isNearlyMatchingFunction(ASTContext &Context, 1375 FunctionDecl *Declaration, 1376 FunctionDecl *Definition) { 1377 if (Declaration->param_size() != Definition->param_size()) 1378 return false; 1379 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1380 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1381 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1382 1383 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1384 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1385 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1386 return false; 1387 } 1388 1389 return true; 1390} 1391 1392Sema::DeclPtrTy 1393Sema::HandleDeclarator(Scope *S, Declarator &D, 1394 MultiTemplateParamsArg TemplateParamLists, 1395 bool IsFunctionDefinition) { 1396 DeclarationName Name = GetNameForDeclarator(D); 1397 1398 // All of these full declarators require an identifier. If it doesn't have 1399 // one, the ParsedFreeStandingDeclSpec action should be used. 1400 if (!Name) { 1401 if (!D.isInvalidType()) // Reject this if we think it is valid. 1402 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1403 diag::err_declarator_need_ident) 1404 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1405 return DeclPtrTy(); 1406 } 1407 1408 // The scope passed in may not be a decl scope. Zip up the scope tree until 1409 // we find one that is. 1410 while ((S->getFlags() & Scope::DeclScope) == 0 || 1411 (S->getFlags() & Scope::TemplateParamScope) != 0) 1412 S = S->getParent(); 1413 1414 DeclContext *DC; 1415 NamedDecl *PrevDecl; 1416 NamedDecl *New; 1417 1418 QualType R = GetTypeForDeclarator(D, S); 1419 1420 // See if this is a redefinition of a variable in the same scope. 1421 if (D.getCXXScopeSpec().isInvalid()) { 1422 DC = CurContext; 1423 PrevDecl = 0; 1424 D.setInvalidType(); 1425 } else if (!D.getCXXScopeSpec().isSet()) { 1426 LookupNameKind NameKind = LookupOrdinaryName; 1427 1428 // If the declaration we're planning to build will be a function 1429 // or object with linkage, then look for another declaration with 1430 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1431 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1432 /* Do nothing*/; 1433 else if (R->isFunctionType()) { 1434 if (CurContext->isFunctionOrMethod()) 1435 NameKind = LookupRedeclarationWithLinkage; 1436 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1437 NameKind = LookupRedeclarationWithLinkage; 1438 1439 DC = CurContext; 1440 PrevDecl = LookupName(S, Name, NameKind, true, 1441 D.getDeclSpec().getStorageClassSpec() != 1442 DeclSpec::SCS_static, 1443 D.getIdentifierLoc()); 1444 } else { // Something like "int foo::x;" 1445 DC = computeDeclContext(D.getCXXScopeSpec()); 1446 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1447 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1448 1449 // C++ 7.3.1.2p2: 1450 // Members (including explicit specializations of templates) of a named 1451 // namespace can also be defined outside that namespace by explicit 1452 // qualification of the name being defined, provided that the entity being 1453 // defined was already declared in the namespace and the definition appears 1454 // after the point of declaration in a namespace that encloses the 1455 // declarations namespace. 1456 // 1457 // Note that we only check the context at this point. We don't yet 1458 // have enough information to make sure that PrevDecl is actually 1459 // the declaration we want to match. For example, given: 1460 // 1461 // class X { 1462 // void f(); 1463 // void f(float); 1464 // }; 1465 // 1466 // void X::f(int) { } // ill-formed 1467 // 1468 // In this case, PrevDecl will point to the overload set 1469 // containing the two f's declared in X, but neither of them 1470 // matches. 1471 1472 // First check whether we named the global scope. 1473 if (isa<TranslationUnitDecl>(DC)) { 1474 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1475 << Name << D.getCXXScopeSpec().getRange(); 1476 } else if (!CurContext->Encloses(DC)) { 1477 // The qualifying scope doesn't enclose the original declaration. 1478 // Emit diagnostic based on current scope. 1479 SourceLocation L = D.getIdentifierLoc(); 1480 SourceRange R = D.getCXXScopeSpec().getRange(); 1481 if (isa<FunctionDecl>(CurContext)) 1482 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1483 else 1484 Diag(L, diag::err_invalid_declarator_scope) 1485 << Name << cast<NamedDecl>(DC) << R; 1486 D.setInvalidType(); 1487 } 1488 } 1489 1490 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1491 // Maybe we will complain about the shadowed template parameter. 1492 if (!D.isInvalidType()) 1493 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1494 D.setInvalidType(); 1495 1496 // Just pretend that we didn't see the previous declaration. 1497 PrevDecl = 0; 1498 } 1499 1500 // In C++, the previous declaration we find might be a tag type 1501 // (class or enum). In this case, the new declaration will hide the 1502 // tag type. Note that this does does not apply if we're declaring a 1503 // typedef (C++ [dcl.typedef]p4). 1504 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1505 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1506 PrevDecl = 0; 1507 1508 bool Redeclaration = false; 1509 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1510 if (TemplateParamLists.size()) { 1511 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1512 return DeclPtrTy(); 1513 } 1514 1515 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1516 } else if (R->isFunctionType()) { 1517 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1518 move(TemplateParamLists), 1519 IsFunctionDefinition, Redeclaration); 1520 } else { 1521 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1522 } 1523 1524 if (New == 0) 1525 return DeclPtrTy(); 1526 1527 // If this has an identifier and is not an invalid redeclaration, 1528 // add it to the scope stack. 1529 if (Name && !(Redeclaration && New->isInvalidDecl())) 1530 PushOnScopeChains(New, S); 1531 1532 return DeclPtrTy::make(New); 1533} 1534 1535/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1536/// types into constant array types in certain situations which would otherwise 1537/// be errors (for GCC compatibility). 1538static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1539 ASTContext &Context, 1540 bool &SizeIsNegative) { 1541 // This method tries to turn a variable array into a constant 1542 // array even when the size isn't an ICE. This is necessary 1543 // for compatibility with code that depends on gcc's buggy 1544 // constant expression folding, like struct {char x[(int)(char*)2];} 1545 SizeIsNegative = false; 1546 1547 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1548 QualType Pointee = PTy->getPointeeType(); 1549 QualType FixedType = 1550 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1551 if (FixedType.isNull()) return FixedType; 1552 FixedType = Context.getPointerType(FixedType); 1553 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1554 return FixedType; 1555 } 1556 1557 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1558 if (!VLATy) 1559 return QualType(); 1560 // FIXME: We should probably handle this case 1561 if (VLATy->getElementType()->isVariablyModifiedType()) 1562 return QualType(); 1563 1564 Expr::EvalResult EvalResult; 1565 if (!VLATy->getSizeExpr() || 1566 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1567 !EvalResult.Val.isInt()) 1568 return QualType(); 1569 1570 llvm::APSInt &Res = EvalResult.Val.getInt(); 1571 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1572 return Context.getConstantArrayType(VLATy->getElementType(), 1573 Res, ArrayType::Normal, 0); 1574 1575 SizeIsNegative = true; 1576 return QualType(); 1577} 1578 1579/// \brief Register the given locally-scoped external C declaration so 1580/// that it can be found later for redeclarations 1581void 1582Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1583 Scope *S) { 1584 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1585 "Decl is not a locally-scoped decl!"); 1586 // Note that we have a locally-scoped external with this name. 1587 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1588 1589 if (!PrevDecl) 1590 return; 1591 1592 // If there was a previous declaration of this variable, it may be 1593 // in our identifier chain. Update the identifier chain with the new 1594 // declaration. 1595 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1596 // The previous declaration was found on the identifer resolver 1597 // chain, so remove it from its scope. 1598 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1599 S = S->getParent(); 1600 1601 if (S) 1602 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1603 } 1604} 1605 1606/// \brief Diagnose function specifiers on a declaration of an identifier that 1607/// does not identify a function. 1608void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1609 // FIXME: We should probably indicate the identifier in question to avoid 1610 // confusion for constructs like "inline int a(), b;" 1611 if (D.getDeclSpec().isInlineSpecified()) 1612 Diag(D.getDeclSpec().getInlineSpecLoc(), 1613 diag::err_inline_non_function); 1614 1615 if (D.getDeclSpec().isVirtualSpecified()) 1616 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1617 diag::err_virtual_non_function); 1618 1619 if (D.getDeclSpec().isExplicitSpecified()) 1620 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1621 diag::err_explicit_non_function); 1622} 1623 1624NamedDecl* 1625Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1626 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1627 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1628 if (D.getCXXScopeSpec().isSet()) { 1629 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1630 << D.getCXXScopeSpec().getRange(); 1631 D.setInvalidType(); 1632 // Pretend we didn't see the scope specifier. 1633 DC = 0; 1634 } 1635 1636 if (getLangOptions().CPlusPlus) { 1637 // Check that there are no default arguments (C++ only). 1638 CheckExtraCXXDefaultArguments(D); 1639 } 1640 1641 DiagnoseFunctionSpecifiers(D); 1642 1643 if (D.getDeclSpec().isThreadSpecified()) 1644 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1645 1646 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1647 if (!NewTD) return 0; 1648 1649 if (D.isInvalidType()) 1650 NewTD->setInvalidDecl(); 1651 1652 // Handle attributes prior to checking for duplicates in MergeVarDecl 1653 ProcessDeclAttributes(S, NewTD, D); 1654 // Merge the decl with the existing one if appropriate. If the decl is 1655 // in an outer scope, it isn't the same thing. 1656 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1657 Redeclaration = true; 1658 MergeTypeDefDecl(NewTD, PrevDecl); 1659 } 1660 1661 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1662 // then it shall have block scope. 1663 QualType T = NewTD->getUnderlyingType(); 1664 if (T->isVariablyModifiedType()) { 1665 CurFunctionNeedsScopeChecking = true; 1666 1667 if (S->getFnParent() == 0) { 1668 bool SizeIsNegative; 1669 QualType FixedTy = 1670 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1671 if (!FixedTy.isNull()) { 1672 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1673 NewTD->setUnderlyingType(FixedTy); 1674 } else { 1675 if (SizeIsNegative) 1676 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1677 else if (T->isVariableArrayType()) 1678 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1679 else 1680 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1681 NewTD->setInvalidDecl(); 1682 } 1683 } 1684 } 1685 return NewTD; 1686} 1687 1688/// \brief Determines whether the given declaration is an out-of-scope 1689/// previous declaration. 1690/// 1691/// This routine should be invoked when name lookup has found a 1692/// previous declaration (PrevDecl) that is not in the scope where a 1693/// new declaration by the same name is being introduced. If the new 1694/// declaration occurs in a local scope, previous declarations with 1695/// linkage may still be considered previous declarations (C99 1696/// 6.2.2p4-5, C++ [basic.link]p6). 1697/// 1698/// \param PrevDecl the previous declaration found by name 1699/// lookup 1700/// 1701/// \param DC the context in which the new declaration is being 1702/// declared. 1703/// 1704/// \returns true if PrevDecl is an out-of-scope previous declaration 1705/// for a new delcaration with the same name. 1706static bool 1707isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1708 ASTContext &Context) { 1709 if (!PrevDecl) 1710 return 0; 1711 1712 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1713 // case we need to check each of the overloaded functions. 1714 if (!PrevDecl->hasLinkage()) 1715 return false; 1716 1717 if (Context.getLangOptions().CPlusPlus) { 1718 // C++ [basic.link]p6: 1719 // If there is a visible declaration of an entity with linkage 1720 // having the same name and type, ignoring entities declared 1721 // outside the innermost enclosing namespace scope, the block 1722 // scope declaration declares that same entity and receives the 1723 // linkage of the previous declaration. 1724 DeclContext *OuterContext = DC->getLookupContext(); 1725 if (!OuterContext->isFunctionOrMethod()) 1726 // This rule only applies to block-scope declarations. 1727 return false; 1728 else { 1729 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1730 if (PrevOuterContext->isRecord()) 1731 // We found a member function: ignore it. 1732 return false; 1733 else { 1734 // Find the innermost enclosing namespace for the new and 1735 // previous declarations. 1736 while (!OuterContext->isFileContext()) 1737 OuterContext = OuterContext->getParent(); 1738 while (!PrevOuterContext->isFileContext()) 1739 PrevOuterContext = PrevOuterContext->getParent(); 1740 1741 // The previous declaration is in a different namespace, so it 1742 // isn't the same function. 1743 if (OuterContext->getPrimaryContext() != 1744 PrevOuterContext->getPrimaryContext()) 1745 return false; 1746 } 1747 } 1748 } 1749 1750 return true; 1751} 1752 1753NamedDecl* 1754Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1755 QualType R,NamedDecl* PrevDecl, 1756 bool &Redeclaration) { 1757 DeclarationName Name = GetNameForDeclarator(D); 1758 1759 // Check that there are no default arguments (C++ only). 1760 if (getLangOptions().CPlusPlus) 1761 CheckExtraCXXDefaultArguments(D); 1762 1763 VarDecl *NewVD; 1764 VarDecl::StorageClass SC; 1765 switch (D.getDeclSpec().getStorageClassSpec()) { 1766 default: assert(0 && "Unknown storage class!"); 1767 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1768 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1769 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1770 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1771 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1772 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1773 case DeclSpec::SCS_mutable: 1774 // mutable can only appear on non-static class members, so it's always 1775 // an error here 1776 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1777 D.setInvalidType(); 1778 SC = VarDecl::None; 1779 break; 1780 } 1781 1782 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1783 if (!II) { 1784 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1785 << Name.getAsString(); 1786 return 0; 1787 } 1788 1789 DiagnoseFunctionSpecifiers(D); 1790 1791 if (!DC->isRecord() && S->getFnParent() == 0) { 1792 // C99 6.9p2: The storage-class specifiers auto and register shall not 1793 // appear in the declaration specifiers in an external declaration. 1794 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1795 1796 // If this is a register variable with an asm label specified, then this 1797 // is a GNU extension. 1798 if (SC == VarDecl::Register && D.getAsmLabel()) 1799 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1800 else 1801 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1802 D.setInvalidType(); 1803 } 1804 } 1805 if (DC->isRecord() && !CurContext->isRecord()) { 1806 // This is an out-of-line definition of a static data member. 1807 if (SC == VarDecl::Static) { 1808 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1809 diag::err_static_out_of_line) 1810 << CodeModificationHint::CreateRemoval( 1811 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1812 } else if (SC == VarDecl::None) 1813 SC = VarDecl::Static; 1814 } 1815 if (SC == VarDecl::Static) { 1816 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 1817 if (RD->isLocalClass()) 1818 Diag(D.getIdentifierLoc(), 1819 diag::err_static_data_member_not_allowed_in_local_class) 1820 << Name << RD->getDeclName(); 1821 } 1822 } 1823 1824 1825 // The variable can not 1826 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1827 II, R, SC, 1828 // FIXME: Move to DeclGroup... 1829 D.getDeclSpec().getSourceRange().getBegin()); 1830 1831 if (D.isInvalidType()) 1832 NewVD->setInvalidDecl(); 1833 1834 if (D.getDeclSpec().isThreadSpecified()) { 1835 if (NewVD->hasLocalStorage()) 1836 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1837 else if (!Context.Target.isTLSSupported()) 1838 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1839 else 1840 NewVD->setThreadSpecified(true); 1841 } 1842 1843 // Set the lexical context. If the declarator has a C++ scope specifier, the 1844 // lexical context will be different from the semantic context. 1845 NewVD->setLexicalDeclContext(CurContext); 1846 1847 // Handle attributes prior to checking for duplicates in MergeVarDecl 1848 ProcessDeclAttributes(S, NewVD, D); 1849 1850 // Handle GNU asm-label extension (encoded as an attribute). 1851 if (Expr *E = (Expr*) D.getAsmLabel()) { 1852 // The parser guarantees this is a string. 1853 StringLiteral *SE = cast<StringLiteral>(E); 1854 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1855 SE->getByteLength()))); 1856 } 1857 1858 // If name lookup finds a previous declaration that is not in the 1859 // same scope as the new declaration, this may still be an 1860 // acceptable redeclaration. 1861 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1862 !(NewVD->hasLinkage() && 1863 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1864 PrevDecl = 0; 1865 1866 // Merge the decl with the existing one if appropriate. 1867 if (PrevDecl) { 1868 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1869 // The user tried to define a non-static data member 1870 // out-of-line (C++ [dcl.meaning]p1). 1871 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1872 << D.getCXXScopeSpec().getRange(); 1873 PrevDecl = 0; 1874 NewVD->setInvalidDecl(); 1875 } 1876 } else if (D.getCXXScopeSpec().isSet()) { 1877 // No previous declaration in the qualifying scope. 1878 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1879 << Name << D.getCXXScopeSpec().getRange(); 1880 NewVD->setInvalidDecl(); 1881 } 1882 1883 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1884 1885 // If this is a locally-scoped extern C variable, update the map of 1886 // such variables. 1887 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1888 !NewVD->isInvalidDecl()) 1889 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1890 1891 return NewVD; 1892} 1893 1894/// \brief Perform semantic checking on a newly-created variable 1895/// declaration. 1896/// 1897/// This routine performs all of the type-checking required for a 1898/// variable declaration once it has been built. It is used both to 1899/// check variables after they have been parsed and their declarators 1900/// have been translated into a declaration, and to check variables 1901/// that have been instantiated from a template. 1902/// 1903/// Sets NewVD->isInvalidDecl() if an error was encountered. 1904void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1905 bool &Redeclaration) { 1906 // If the decl is already known invalid, don't check it. 1907 if (NewVD->isInvalidDecl()) 1908 return; 1909 1910 QualType T = NewVD->getType(); 1911 1912 if (T->isObjCInterfaceType()) { 1913 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1914 return NewVD->setInvalidDecl(); 1915 } 1916 1917 // The variable can not have an abstract class type. 1918 if (RequireNonAbstractType(NewVD->getLocation(), T, 1919 diag::err_abstract_type_in_decl, 1920 AbstractVariableType)) 1921 return NewVD->setInvalidDecl(); 1922 1923 // Emit an error if an address space was applied to decl with local storage. 1924 // This includes arrays of objects with address space qualifiers, but not 1925 // automatic variables that point to other address spaces. 1926 // ISO/IEC TR 18037 S5.1.2 1927 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1928 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1929 return NewVD->setInvalidDecl(); 1930 } 1931 1932 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1933 && !NewVD->hasAttr<BlocksAttr>()) 1934 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1935 1936 bool isVM = T->isVariablyModifiedType(); 1937 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1938 CurFunctionNeedsScopeChecking = true; 1939 1940 if ((isVM && NewVD->hasLinkage()) || 1941 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1942 bool SizeIsNegative; 1943 QualType FixedTy = 1944 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1945 1946 if (FixedTy.isNull() && T->isVariableArrayType()) { 1947 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1948 // FIXME: This won't give the correct result for 1949 // int a[10][n]; 1950 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1951 1952 if (NewVD->isFileVarDecl()) 1953 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1954 << SizeRange; 1955 else if (NewVD->getStorageClass() == VarDecl::Static) 1956 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1957 << SizeRange; 1958 else 1959 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1960 << SizeRange; 1961 return NewVD->setInvalidDecl(); 1962 } 1963 1964 if (FixedTy.isNull()) { 1965 if (NewVD->isFileVarDecl()) 1966 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1967 else 1968 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1969 return NewVD->setInvalidDecl(); 1970 } 1971 1972 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1973 NewVD->setType(FixedTy); 1974 } 1975 1976 if (!PrevDecl && NewVD->isExternC(Context)) { 1977 // Since we did not find anything by this name and we're declaring 1978 // an extern "C" variable, look for a non-visible extern "C" 1979 // declaration with the same name. 1980 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1981 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1982 if (Pos != LocallyScopedExternalDecls.end()) 1983 PrevDecl = Pos->second; 1984 } 1985 1986 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1987 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1988 << T; 1989 return NewVD->setInvalidDecl(); 1990 } 1991 1992 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 1993 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 1994 return NewVD->setInvalidDecl(); 1995 } 1996 1997 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 1998 Diag(NewVD->getLocation(), diag::err_block_on_vm); 1999 return NewVD->setInvalidDecl(); 2000 } 2001 2002 if (PrevDecl) { 2003 Redeclaration = true; 2004 MergeVarDecl(NewVD, PrevDecl); 2005 } 2006} 2007 2008NamedDecl* 2009Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2010 QualType R, NamedDecl* PrevDecl, 2011 MultiTemplateParamsArg TemplateParamLists, 2012 bool IsFunctionDefinition, bool &Redeclaration) { 2013 assert(R.getTypePtr()->isFunctionType()); 2014 2015 DeclarationName Name = GetNameForDeclarator(D); 2016 FunctionDecl::StorageClass SC = FunctionDecl::None; 2017 switch (D.getDeclSpec().getStorageClassSpec()) { 2018 default: assert(0 && "Unknown storage class!"); 2019 case DeclSpec::SCS_auto: 2020 case DeclSpec::SCS_register: 2021 case DeclSpec::SCS_mutable: 2022 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2023 diag::err_typecheck_sclass_func); 2024 D.setInvalidType(); 2025 break; 2026 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2027 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2028 case DeclSpec::SCS_static: { 2029 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2030 // C99 6.7.1p5: 2031 // The declaration of an identifier for a function that has 2032 // block scope shall have no explicit storage-class specifier 2033 // other than extern 2034 // See also (C++ [dcl.stc]p4). 2035 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2036 diag::err_static_block_func); 2037 SC = FunctionDecl::None; 2038 } else 2039 SC = FunctionDecl::Static; 2040 break; 2041 } 2042 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2043 } 2044 2045 if (D.getDeclSpec().isThreadSpecified()) 2046 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2047 2048 bool isInline = D.getDeclSpec().isInlineSpecified(); 2049 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2050 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2051 2052 // Check that the return type is not an abstract class type. 2053 // For record types, this is done by the AbstractClassUsageDiagnoser once 2054 // the class has been completely parsed. 2055 if (!DC->isRecord() && 2056 RequireNonAbstractType(D.getIdentifierLoc(), 2057 R->getAsFunctionType()->getResultType(), 2058 diag::err_abstract_type_in_decl, 2059 AbstractReturnType)) 2060 D.setInvalidType(); 2061 2062 // Do not allow returning a objc interface by-value. 2063 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2064 Diag(D.getIdentifierLoc(), 2065 diag::err_object_cannot_be_passed_returned_by_value) << 0 2066 << R->getAsFunctionType()->getResultType(); 2067 D.setInvalidType(); 2068 } 2069 2070 // Check that we can declare a template here. 2071 if (TemplateParamLists.size() && 2072 CheckTemplateDeclScope(S, TemplateParamLists)) 2073 return 0; 2074 2075 bool isVirtualOkay = false; 2076 FunctionDecl *NewFD; 2077 if (D.getKind() == Declarator::DK_Constructor) { 2078 // This is a C++ constructor declaration. 2079 assert(DC->isRecord() && 2080 "Constructors can only be declared in a member context"); 2081 2082 R = CheckConstructorDeclarator(D, R, SC); 2083 2084 // Create the new declaration 2085 NewFD = CXXConstructorDecl::Create(Context, 2086 cast<CXXRecordDecl>(DC), 2087 D.getIdentifierLoc(), Name, R, 2088 isExplicit, isInline, 2089 /*isImplicitlyDeclared=*/false); 2090 } else if (D.getKind() == Declarator::DK_Destructor) { 2091 // This is a C++ destructor declaration. 2092 if (DC->isRecord()) { 2093 R = CheckDestructorDeclarator(D, SC); 2094 2095 NewFD = CXXDestructorDecl::Create(Context, 2096 cast<CXXRecordDecl>(DC), 2097 D.getIdentifierLoc(), Name, R, 2098 isInline, 2099 /*isImplicitlyDeclared=*/false); 2100 2101 isVirtualOkay = true; 2102 } else { 2103 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2104 2105 // Create a FunctionDecl to satisfy the function definition parsing 2106 // code path. 2107 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2108 Name, R, SC, isInline, 2109 /*hasPrototype=*/true, 2110 // FIXME: Move to DeclGroup... 2111 D.getDeclSpec().getSourceRange().getBegin()); 2112 D.setInvalidType(); 2113 } 2114 } else if (D.getKind() == Declarator::DK_Conversion) { 2115 if (!DC->isRecord()) { 2116 Diag(D.getIdentifierLoc(), 2117 diag::err_conv_function_not_member); 2118 return 0; 2119 } 2120 2121 CheckConversionDeclarator(D, R, SC); 2122 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2123 D.getIdentifierLoc(), Name, R, 2124 isInline, isExplicit); 2125 2126 isVirtualOkay = true; 2127 } else if (DC->isRecord()) { 2128 // If the of the function is the same as the name of the record, then this 2129 // must be an invalid constructor that has a return type. 2130 // (The parser checks for a return type and makes the declarator a 2131 // constructor if it has no return type). 2132 // must have an invalid constructor that has a return type 2133 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2134 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2135 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2136 << SourceRange(D.getIdentifierLoc()); 2137 return 0; 2138 } 2139 2140 // This is a C++ method declaration. 2141 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2142 D.getIdentifierLoc(), Name, R, 2143 (SC == FunctionDecl::Static), isInline); 2144 2145 isVirtualOkay = (SC != FunctionDecl::Static); 2146 } else { 2147 // Determine whether the function was written with a 2148 // prototype. This true when: 2149 // - we're in C++ (where every function has a prototype), 2150 // - there is a prototype in the declarator, or 2151 // - the type R of the function is some kind of typedef or other reference 2152 // to a type name (which eventually refers to a function type). 2153 bool HasPrototype = 2154 getLangOptions().CPlusPlus || 2155 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2156 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2157 2158 NewFD = FunctionDecl::Create(Context, DC, 2159 D.getIdentifierLoc(), 2160 Name, R, SC, isInline, HasPrototype, 2161 // FIXME: Move to DeclGroup... 2162 D.getDeclSpec().getSourceRange().getBegin()); 2163 } 2164 2165 if (D.isInvalidType()) 2166 NewFD->setInvalidDecl(); 2167 2168 // Set the lexical context. If the declarator has a C++ 2169 // scope specifier, the lexical context will be different 2170 // from the semantic context. 2171 NewFD->setLexicalDeclContext(CurContext); 2172 2173 // If there is a template parameter list, then we are dealing with a 2174 // template declaration or specialization. 2175 FunctionTemplateDecl *FunctionTemplate = 0; 2176 if (TemplateParamLists.size()) { 2177 // FIXME: member templates! 2178 TemplateParameterList *TemplateParams 2179 = static_cast<TemplateParameterList *>(*TemplateParamLists.release()); 2180 2181 if (TemplateParams->size() > 0) { 2182 // This is a function template 2183 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2184 NewFD->getLocation(), 2185 Name, TemplateParams, 2186 NewFD); 2187 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2188 } else { 2189 // FIXME: Handle function template specializations 2190 } 2191 } 2192 2193 // C++ [dcl.fct.spec]p5: 2194 // The virtual specifier shall only be used in declarations of 2195 // nonstatic class member functions that appear within a 2196 // member-specification of a class declaration; see 10.3. 2197 // 2198 if (isVirtual && !NewFD->isInvalidDecl()) { 2199 if (!isVirtualOkay) { 2200 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2201 diag::err_virtual_non_function); 2202 } else if (!CurContext->isRecord()) { 2203 // 'virtual' was specified outside of the class. 2204 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2205 << CodeModificationHint::CreateRemoval( 2206 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2207 } else { 2208 // Okay: Add virtual to the method. 2209 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2210 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2211 CurClass->setAggregate(false); 2212 CurClass->setPOD(false); 2213 CurClass->setPolymorphic(true); 2214 CurClass->setHasTrivialConstructor(false); 2215 } 2216 } 2217 2218 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2219 // Look for virtual methods in base classes that this method might override. 2220 2221 BasePaths Paths; 2222 if (LookupInBases(cast<CXXRecordDecl>(DC), 2223 MemberLookupCriteria(NewMD), Paths)) { 2224 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2225 E = Paths.found_decls_end(); I != E; ++I) { 2226 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2227 if (!CheckOverridingFunctionReturnType(NewMD, OldMD)) 2228 NewMD->addOverriddenMethod(OldMD); 2229 } 2230 } 2231 } 2232 } 2233 2234 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2235 !CurContext->isRecord()) { 2236 // C++ [class.static]p1: 2237 // A data or function member of a class may be declared static 2238 // in a class definition, in which case it is a static member of 2239 // the class. 2240 2241 // Complain about the 'static' specifier if it's on an out-of-line 2242 // member function definition. 2243 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2244 diag::err_static_out_of_line) 2245 << CodeModificationHint::CreateRemoval( 2246 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2247 } 2248 2249 // Handle GNU asm-label extension (encoded as an attribute). 2250 if (Expr *E = (Expr*) D.getAsmLabel()) { 2251 // The parser guarantees this is a string. 2252 StringLiteral *SE = cast<StringLiteral>(E); 2253 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2254 SE->getByteLength()))); 2255 } 2256 2257 // Copy the parameter declarations from the declarator D to the function 2258 // declaration NewFD, if they are available. First scavenge them into Params. 2259 llvm::SmallVector<ParmVarDecl*, 16> Params; 2260 if (D.getNumTypeObjects() > 0) { 2261 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2262 2263 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2264 // function that takes no arguments, not a function that takes a 2265 // single void argument. 2266 // We let through "const void" here because Sema::GetTypeForDeclarator 2267 // already checks for that case. 2268 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2269 FTI.ArgInfo[0].Param && 2270 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2271 // Empty arg list, don't push any params. 2272 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2273 2274 // In C++, the empty parameter-type-list must be spelled "void"; a 2275 // typedef of void is not permitted. 2276 if (getLangOptions().CPlusPlus && 2277 Param->getType().getUnqualifiedType() != Context.VoidTy) 2278 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2279 // FIXME: Leaks decl? 2280 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2281 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2282 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2283 } 2284 2285 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2286 // When we're declaring a function with a typedef, typeof, etc as in the 2287 // following example, we'll need to synthesize (unnamed) 2288 // parameters for use in the declaration. 2289 // 2290 // @code 2291 // typedef void fn(int); 2292 // fn f; 2293 // @endcode 2294 2295 // Synthesize a parameter for each argument type. 2296 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2297 AE = FT->arg_type_end(); AI != AE; ++AI) { 2298 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2299 SourceLocation(), 0, 2300 *AI, VarDecl::None, 0); 2301 Param->setImplicit(); 2302 Params.push_back(Param); 2303 } 2304 } else { 2305 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2306 "Should not need args for typedef of non-prototype fn"); 2307 } 2308 // Finally, we know we have the right number of parameters, install them. 2309 NewFD->setParams(Context, Params.data(), Params.size()); 2310 2311 // If name lookup finds a previous declaration that is not in the 2312 // same scope as the new declaration, this may still be an 2313 // acceptable redeclaration. 2314 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2315 !(NewFD->hasLinkage() && 2316 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2317 PrevDecl = 0; 2318 2319 // Perform semantic checking on the function declaration. 2320 bool OverloadableAttrRequired = false; // FIXME: HACK! 2321 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2322 /*FIXME:*/OverloadableAttrRequired); 2323 2324 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2325 // An out-of-line member function declaration must also be a 2326 // definition (C++ [dcl.meaning]p1). 2327 if (!IsFunctionDefinition) { 2328 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2329 << D.getCXXScopeSpec().getRange(); 2330 NewFD->setInvalidDecl(); 2331 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2332 // The user tried to provide an out-of-line definition for a 2333 // function that is a member of a class or namespace, but there 2334 // was no such member function declared (C++ [class.mfct]p2, 2335 // C++ [namespace.memdef]p2). For example: 2336 // 2337 // class X { 2338 // void f() const; 2339 // }; 2340 // 2341 // void X::f() { } // ill-formed 2342 // 2343 // Complain about this problem, and attempt to suggest close 2344 // matches (e.g., those that differ only in cv-qualifiers and 2345 // whether the parameter types are references). 2346 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2347 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2348 NewFD->setInvalidDecl(); 2349 2350 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2351 true); 2352 assert(!Prev.isAmbiguous() && 2353 "Cannot have an ambiguity in previous-declaration lookup"); 2354 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2355 Func != FuncEnd; ++Func) { 2356 if (isa<FunctionDecl>(*Func) && 2357 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2358 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2359 } 2360 2361 PrevDecl = 0; 2362 } 2363 } 2364 2365 // Handle attributes. We need to have merged decls when handling attributes 2366 // (for example to check for conflicts, etc). 2367 // FIXME: This needs to happen before we merge declarations. Then, 2368 // let attribute merging cope with attribute conflicts. 2369 ProcessDeclAttributes(S, NewFD, D); 2370 AddKnownFunctionAttributes(NewFD); 2371 2372 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2373 // If a function name is overloadable in C, then every function 2374 // with that name must be marked "overloadable". 2375 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2376 << Redeclaration << NewFD; 2377 if (PrevDecl) 2378 Diag(PrevDecl->getLocation(), 2379 diag::note_attribute_overloadable_prev_overload); 2380 NewFD->addAttr(::new (Context) OverloadableAttr()); 2381 } 2382 2383 // If this is a locally-scoped extern C function, update the 2384 // map of such names. 2385 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2386 && !NewFD->isInvalidDecl()) 2387 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2388 2389 // Set this FunctionDecl's range up to the right paren. 2390 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2391 2392 if (FunctionTemplate && NewFD->isInvalidDecl()) 2393 FunctionTemplate->setInvalidDecl(); 2394 2395 if (FunctionTemplate) 2396 return FunctionTemplate; 2397 2398 return NewFD; 2399} 2400 2401/// \brief Perform semantic checking of a new function declaration. 2402/// 2403/// Performs semantic analysis of the new function declaration 2404/// NewFD. This routine performs all semantic checking that does not 2405/// require the actual declarator involved in the declaration, and is 2406/// used both for the declaration of functions as they are parsed 2407/// (called via ActOnDeclarator) and for the declaration of functions 2408/// that have been instantiated via C++ template instantiation (called 2409/// via InstantiateDecl). 2410/// 2411/// This sets NewFD->isInvalidDecl() to true if there was an error. 2412void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2413 bool &Redeclaration, 2414 bool &OverloadableAttrRequired) { 2415 // If NewFD is already known erroneous, don't do any of this checking. 2416 if (NewFD->isInvalidDecl()) 2417 return; 2418 2419 if (NewFD->getResultType()->isVariablyModifiedType()) { 2420 // Functions returning a variably modified type violate C99 6.7.5.2p2 2421 // because all functions have linkage. 2422 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2423 return NewFD->setInvalidDecl(); 2424 } 2425 2426 // Semantic checking for this function declaration (in isolation). 2427 if (getLangOptions().CPlusPlus) { 2428 // C++-specific checks. 2429 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2430 CheckConstructor(Constructor); 2431 } else if (isa<CXXDestructorDecl>(NewFD)) { 2432 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2433 Record->setUserDeclaredDestructor(true); 2434 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2435 // user-defined destructor. 2436 Record->setPOD(false); 2437 2438 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2439 // declared destructor. 2440 Record->setHasTrivialDestructor(false); 2441 } else if (CXXConversionDecl *Conversion 2442 = dyn_cast<CXXConversionDecl>(NewFD)) 2443 ActOnConversionDeclarator(Conversion); 2444 2445 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2446 if (NewFD->isOverloadedOperator() && 2447 CheckOverloadedOperatorDeclaration(NewFD)) 2448 return NewFD->setInvalidDecl(); 2449 } 2450 2451 // C99 6.7.4p6: 2452 // [... ] For a function with external linkage, the following 2453 // restrictions apply: [...] If all of the file scope declarations 2454 // for a function in a translation unit include the inline 2455 // function specifier without extern, then the definition in that 2456 // translation unit is an inline definition. An inline definition 2457 // does not provide an external definition for the function, and 2458 // does not forbid an external definition in another translation 2459 // unit. 2460 // 2461 // Here we determine whether this function, in isolation, would be a 2462 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2463 // previous declarations. 2464 if (NewFD->isInline() && getLangOptions().C99 && 2465 NewFD->getStorageClass() == FunctionDecl::None && 2466 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2467 NewFD->setC99InlineDefinition(true); 2468 2469 // Check for a previous declaration of this name. 2470 if (!PrevDecl && NewFD->isExternC(Context)) { 2471 // Since we did not find anything by this name and we're declaring 2472 // an extern "C" function, look for a non-visible extern "C" 2473 // declaration with the same name. 2474 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2475 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2476 if (Pos != LocallyScopedExternalDecls.end()) 2477 PrevDecl = Pos->second; 2478 } 2479 2480 // Merge or overload the declaration with an existing declaration of 2481 // the same name, if appropriate. 2482 if (PrevDecl) { 2483 // Determine whether NewFD is an overload of PrevDecl or 2484 // a declaration that requires merging. If it's an overload, 2485 // there's no more work to do here; we'll just add the new 2486 // function to the scope. 2487 OverloadedFunctionDecl::function_iterator MatchedDecl; 2488 2489 if (!getLangOptions().CPlusPlus && 2490 AllowOverloadingOfFunction(PrevDecl, Context)) { 2491 OverloadableAttrRequired = true; 2492 2493 // Functions marked "overloadable" must have a prototype (that 2494 // we can't get through declaration merging). 2495 if (!NewFD->getType()->getAsFunctionProtoType()) { 2496 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2497 << NewFD; 2498 Redeclaration = true; 2499 2500 // Turn this into a variadic function with no parameters. 2501 QualType R = Context.getFunctionType( 2502 NewFD->getType()->getAsFunctionType()->getResultType(), 2503 0, 0, true, 0); 2504 NewFD->setType(R); 2505 return NewFD->setInvalidDecl(); 2506 } 2507 } 2508 2509 if (PrevDecl && 2510 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2511 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2512 !isa<UsingDecl>(PrevDecl)) { 2513 Redeclaration = true; 2514 Decl *OldDecl = PrevDecl; 2515 2516 // If PrevDecl was an overloaded function, extract the 2517 // FunctionDecl that matched. 2518 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2519 OldDecl = *MatchedDecl; 2520 2521 // NewFD and OldDecl represent declarations that need to be 2522 // merged. 2523 if (MergeFunctionDecl(NewFD, OldDecl)) 2524 return NewFD->setInvalidDecl(); 2525 2526 if (FunctionTemplateDecl *OldTemplateDecl 2527 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2528 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2529 else 2530 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2531 } 2532 } 2533 2534 // In C++, check default arguments now that we have merged decls. Unless 2535 // the lexical context is the class, because in this case this is done 2536 // during delayed parsing anyway. 2537 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2538 CheckCXXDefaultArguments(NewFD); 2539} 2540 2541bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2542 // FIXME: Need strict checking. In C89, we need to check for 2543 // any assignment, increment, decrement, function-calls, or 2544 // commas outside of a sizeof. In C99, it's the same list, 2545 // except that the aforementioned are allowed in unevaluated 2546 // expressions. Everything else falls under the 2547 // "may accept other forms of constant expressions" exception. 2548 // (We never end up here for C++, so the constant expression 2549 // rules there don't matter.) 2550 if (Init->isConstantInitializer(Context)) 2551 return false; 2552 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2553 << Init->getSourceRange(); 2554 return true; 2555} 2556 2557void Sema::AddInitializerToDecl(DeclPtrTy dcl, FullExprArg init) { 2558 AddInitializerToDecl(dcl, init.release(), /*DirectInit=*/false); 2559} 2560 2561/// AddInitializerToDecl - Adds the initializer Init to the 2562/// declaration dcl. If DirectInit is true, this is C++ direct 2563/// initialization rather than copy initialization. 2564void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2565 Decl *RealDecl = dcl.getAs<Decl>(); 2566 // If there is no declaration, there was an error parsing it. Just ignore 2567 // the initializer. 2568 if (RealDecl == 0) 2569 return; 2570 2571 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2572 // With declarators parsed the way they are, the parser cannot 2573 // distinguish between a normal initializer and a pure-specifier. 2574 // Thus this grotesque test. 2575 IntegerLiteral *IL; 2576 Expr *Init = static_cast<Expr *>(init.get()); 2577 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2578 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2579 if (Method->isVirtualAsWritten()) { 2580 Method->setPure(); 2581 2582 // A class is abstract if at least one function is pure virtual. 2583 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2584 } else if (!Method->isInvalidDecl()) { 2585 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2586 << Method->getDeclName() << Init->getSourceRange(); 2587 Method->setInvalidDecl(); 2588 } 2589 } else { 2590 Diag(Method->getLocation(), diag::err_member_function_initialization) 2591 << Method->getDeclName() << Init->getSourceRange(); 2592 Method->setInvalidDecl(); 2593 } 2594 return; 2595 } 2596 2597 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2598 if (!VDecl) { 2599 if (getLangOptions().CPlusPlus && 2600 RealDecl->getLexicalDeclContext()->isRecord() && 2601 isa<NamedDecl>(RealDecl)) 2602 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2603 << cast<NamedDecl>(RealDecl)->getDeclName(); 2604 else 2605 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2606 RealDecl->setInvalidDecl(); 2607 return; 2608 } 2609 2610 if (!VDecl->getType()->isArrayType() && 2611 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2612 diag::err_typecheck_decl_incomplete_type)) { 2613 RealDecl->setInvalidDecl(); 2614 return; 2615 } 2616 2617 const VarDecl *Def = 0; 2618 if (VDecl->getDefinition(Def)) { 2619 Diag(VDecl->getLocation(), diag::err_redefinition) 2620 << VDecl->getDeclName(); 2621 Diag(Def->getLocation(), diag::note_previous_definition); 2622 VDecl->setInvalidDecl(); 2623 return; 2624 } 2625 2626 // Take ownership of the expression, now that we're sure we have somewhere 2627 // to put it. 2628 Expr *Init = init.takeAs<Expr>(); 2629 assert(Init && "missing initializer"); 2630 2631 // Get the decls type and save a reference for later, since 2632 // CheckInitializerTypes may change it. 2633 QualType DclT = VDecl->getType(), SavT = DclT; 2634 if (VDecl->isBlockVarDecl()) { 2635 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2636 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2637 VDecl->setInvalidDecl(); 2638 } else if (!VDecl->isInvalidDecl()) { 2639 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2640 VDecl->getDeclName(), DirectInit)) 2641 VDecl->setInvalidDecl(); 2642 2643 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2644 // Don't check invalid declarations to avoid emitting useless diagnostics. 2645 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2646 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2647 CheckForConstantInitializer(Init, DclT); 2648 } 2649 } 2650 } else if (VDecl->isStaticDataMember() && 2651 VDecl->getLexicalDeclContext()->isRecord()) { 2652 // This is an in-class initialization for a static data member, e.g., 2653 // 2654 // struct S { 2655 // static const int value = 17; 2656 // }; 2657 2658 // Attach the initializer 2659 VDecl->setInit(Context, Init); 2660 2661 // C++ [class.mem]p4: 2662 // A member-declarator can contain a constant-initializer only 2663 // if it declares a static member (9.4) of const integral or 2664 // const enumeration type, see 9.4.2. 2665 QualType T = VDecl->getType(); 2666 if (!T->isDependentType() && 2667 (!Context.getCanonicalType(T).isConstQualified() || 2668 !T->isIntegralType())) { 2669 Diag(VDecl->getLocation(), diag::err_member_initialization) 2670 << VDecl->getDeclName() << Init->getSourceRange(); 2671 VDecl->setInvalidDecl(); 2672 } else { 2673 // C++ [class.static.data]p4: 2674 // If a static data member is of const integral or const 2675 // enumeration type, its declaration in the class definition 2676 // can specify a constant-initializer which shall be an 2677 // integral constant expression (5.19). 2678 if (!Init->isTypeDependent() && 2679 !Init->getType()->isIntegralType()) { 2680 // We have a non-dependent, non-integral or enumeration type. 2681 Diag(Init->getSourceRange().getBegin(), 2682 diag::err_in_class_initializer_non_integral_type) 2683 << Init->getType() << Init->getSourceRange(); 2684 VDecl->setInvalidDecl(); 2685 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2686 // Check whether the expression is a constant expression. 2687 llvm::APSInt Value; 2688 SourceLocation Loc; 2689 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2690 Diag(Loc, diag::err_in_class_initializer_non_constant) 2691 << Init->getSourceRange(); 2692 VDecl->setInvalidDecl(); 2693 } else if (!VDecl->getType()->isDependentType()) 2694 ImpCastExprToType(Init, VDecl->getType()); 2695 } 2696 } 2697 } else if (VDecl->isFileVarDecl()) { 2698 if (VDecl->getStorageClass() == VarDecl::Extern) 2699 Diag(VDecl->getLocation(), diag::warn_extern_init); 2700 if (!VDecl->isInvalidDecl()) 2701 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2702 VDecl->getDeclName(), DirectInit)) 2703 VDecl->setInvalidDecl(); 2704 2705 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2706 // Don't check invalid declarations to avoid emitting useless diagnostics. 2707 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2708 // C99 6.7.8p4. All file scoped initializers need to be constant. 2709 CheckForConstantInitializer(Init, DclT); 2710 } 2711 } 2712 // If the type changed, it means we had an incomplete type that was 2713 // completed by the initializer. For example: 2714 // int ary[] = { 1, 3, 5 }; 2715 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2716 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2717 VDecl->setType(DclT); 2718 Init->setType(DclT); 2719 } 2720 2721 // Attach the initializer to the decl. 2722 VDecl->setInit(Context, Init); 2723 2724 // If the previous declaration of VDecl was a tentative definition, 2725 // remove it from the set of tentative definitions. 2726 if (VDecl->getPreviousDeclaration() && 2727 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2728 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2729 = TentativeDefinitions.find(VDecl->getDeclName()); 2730 assert(Pos != TentativeDefinitions.end() && 2731 "Unrecorded tentative definition?"); 2732 TentativeDefinitions.erase(Pos); 2733 } 2734 2735 return; 2736} 2737 2738void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2739 Decl *RealDecl = dcl.getAs<Decl>(); 2740 2741 // If there is no declaration, there was an error parsing it. Just ignore it. 2742 if (RealDecl == 0) 2743 return; 2744 2745 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2746 QualType Type = Var->getType(); 2747 2748 // Record tentative definitions. 2749 if (Var->isTentativeDefinition(Context)) 2750 TentativeDefinitions[Var->getDeclName()] = Var; 2751 2752 // C++ [dcl.init.ref]p3: 2753 // The initializer can be omitted for a reference only in a 2754 // parameter declaration (8.3.5), in the declaration of a 2755 // function return type, in the declaration of a class member 2756 // within its class declaration (9.2), and where the extern 2757 // specifier is explicitly used. 2758 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2759 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2760 << Var->getDeclName() 2761 << SourceRange(Var->getLocation(), Var->getLocation()); 2762 Var->setInvalidDecl(); 2763 return; 2764 } 2765 2766 // C++ [dcl.init]p9: 2767 // 2768 // If no initializer is specified for an object, and the object 2769 // is of (possibly cv-qualified) non-POD class type (or array 2770 // thereof), the object shall be default-initialized; if the 2771 // object is of const-qualified type, the underlying class type 2772 // shall have a user-declared default constructor. 2773 if (getLangOptions().CPlusPlus) { 2774 QualType InitType = Type; 2775 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2776 InitType = Array->getElementType(); 2777 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 2778 InitType->isRecordType() && !InitType->isDependentType()) { 2779 CXXRecordDecl *RD = 2780 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2781 CXXConstructorDecl *Constructor = 0; 2782 if (!RequireCompleteType(Var->getLocation(), InitType, 2783 diag::err_invalid_incomplete_type_use)) 2784 Constructor 2785 = PerformInitializationByConstructor(InitType, 0, 0, 2786 Var->getLocation(), 2787 SourceRange(Var->getLocation(), 2788 Var->getLocation()), 2789 Var->getDeclName(), 2790 IK_Default); 2791 if (!Constructor) 2792 Var->setInvalidDecl(); 2793 else { 2794 if (!RD->hasTrivialConstructor()) 2795 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2796 // FIXME. Must do all that is needed to destroy the object 2797 // on scope exit. For now, just mark the destructor as used. 2798 MarkDestructorReferenced(Var->getLocation(), InitType); 2799 } 2800 } 2801 } 2802 2803#if 0 2804 // FIXME: Temporarily disabled because we are not properly parsing 2805 // linkage specifications on declarations, e.g., 2806 // 2807 // extern "C" const CGPoint CGPointerZero; 2808 // 2809 // C++ [dcl.init]p9: 2810 // 2811 // If no initializer is specified for an object, and the 2812 // object is of (possibly cv-qualified) non-POD class type (or 2813 // array thereof), the object shall be default-initialized; if 2814 // the object is of const-qualified type, the underlying class 2815 // type shall have a user-declared default 2816 // constructor. Otherwise, if no initializer is specified for 2817 // an object, the object and its subobjects, if any, have an 2818 // indeterminate initial value; if the object or any of its 2819 // subobjects are of const-qualified type, the program is 2820 // ill-formed. 2821 // 2822 // This isn't technically an error in C, so we don't diagnose it. 2823 // 2824 // FIXME: Actually perform the POD/user-defined default 2825 // constructor check. 2826 if (getLangOptions().CPlusPlus && 2827 Context.getCanonicalType(Type).isConstQualified() && 2828 !Var->hasExternalStorage()) 2829 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2830 << Var->getName() 2831 << SourceRange(Var->getLocation(), Var->getLocation()); 2832#endif 2833 } 2834} 2835 2836Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 2837 DeclPtrTy *Group, 2838 unsigned NumDecls) { 2839 llvm::SmallVector<Decl*, 8> Decls; 2840 2841 if (DS.isTypeSpecOwned()) 2842 Decls.push_back((Decl*)DS.getTypeRep()); 2843 2844 for (unsigned i = 0; i != NumDecls; ++i) 2845 if (Decl *D = Group[i].getAs<Decl>()) 2846 Decls.push_back(D); 2847 2848 // Perform semantic analysis that depends on having fully processed both 2849 // the declarator and initializer. 2850 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2851 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2852 if (!IDecl) 2853 continue; 2854 QualType T = IDecl->getType(); 2855 2856 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2857 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2858 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2859 if (!IDecl->isInvalidDecl() && 2860 RequireCompleteType(IDecl->getLocation(), T, 2861 diag::err_typecheck_decl_incomplete_type)) 2862 IDecl->setInvalidDecl(); 2863 } 2864 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2865 // object that has file scope without an initializer, and without a 2866 // storage-class specifier or with the storage-class specifier "static", 2867 // constitutes a tentative definition. Note: A tentative definition with 2868 // external linkage is valid (C99 6.2.2p5). 2869 if (IDecl->isTentativeDefinition(Context)) { 2870 QualType CheckType = T; 2871 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2872 2873 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2874 if (ArrayT) { 2875 CheckType = ArrayT->getElementType(); 2876 DiagID = diag::err_illegal_decl_array_incomplete_type; 2877 } 2878 2879 if (IDecl->isInvalidDecl()) { 2880 // Do nothing with invalid declarations 2881 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2882 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2883 // C99 6.9.2p3: If the declaration of an identifier for an object is 2884 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2885 // declared type shall not be an incomplete type. 2886 IDecl->setInvalidDecl(); 2887 } 2888 } 2889 } 2890 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2891 Decls.data(), Decls.size())); 2892} 2893 2894 2895/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2896/// to introduce parameters into function prototype scope. 2897Sema::DeclPtrTy 2898Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2899 const DeclSpec &DS = D.getDeclSpec(); 2900 2901 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2902 VarDecl::StorageClass StorageClass = VarDecl::None; 2903 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2904 StorageClass = VarDecl::Register; 2905 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2906 Diag(DS.getStorageClassSpecLoc(), 2907 diag::err_invalid_storage_class_in_func_decl); 2908 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2909 } 2910 2911 if (D.getDeclSpec().isThreadSpecified()) 2912 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2913 2914 DiagnoseFunctionSpecifiers(D); 2915 2916 // Check that there are no default arguments inside the type of this 2917 // parameter (C++ only). 2918 if (getLangOptions().CPlusPlus) 2919 CheckExtraCXXDefaultArguments(D); 2920 2921 TagDecl *OwnedDecl = 0; 2922 QualType parmDeclType = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedDecl); 2923 2924 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 2925 // C++ [dcl.fct]p6: 2926 // Types shall not be defined in return or parameter types. 2927 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 2928 << Context.getTypeDeclType(OwnedDecl); 2929 } 2930 2931 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2932 // Can this happen for params? We already checked that they don't conflict 2933 // among each other. Here they can only shadow globals, which is ok. 2934 IdentifierInfo *II = D.getIdentifier(); 2935 if (II) { 2936 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2937 if (PrevDecl->isTemplateParameter()) { 2938 // Maybe we will complain about the shadowed template parameter. 2939 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2940 // Just pretend that we didn't see the previous declaration. 2941 PrevDecl = 0; 2942 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2943 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2944 2945 // Recover by removing the name 2946 II = 0; 2947 D.SetIdentifier(0, D.getIdentifierLoc()); 2948 } 2949 } 2950 } 2951 2952 // Parameters can not be abstract class types. 2953 // For record types, this is done by the AbstractClassUsageDiagnoser once 2954 // the class has been completely parsed. 2955 if (!CurContext->isRecord() && 2956 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2957 diag::err_abstract_type_in_decl, 2958 AbstractParamType)) 2959 D.setInvalidType(true); 2960 2961 QualType T = adjustParameterType(parmDeclType); 2962 2963 ParmVarDecl *New; 2964 if (T == parmDeclType) // parameter type did not need adjustment 2965 New = ParmVarDecl::Create(Context, CurContext, 2966 D.getIdentifierLoc(), II, 2967 parmDeclType, StorageClass, 2968 0); 2969 else // keep track of both the adjusted and unadjusted types 2970 New = OriginalParmVarDecl::Create(Context, CurContext, 2971 D.getIdentifierLoc(), II, T, 2972 parmDeclType, StorageClass, 0); 2973 2974 if (D.isInvalidType()) 2975 New->setInvalidDecl(); 2976 2977 // Parameter declarators cannot be interface types. All ObjC objects are 2978 // passed by reference. 2979 if (T->isObjCInterfaceType()) { 2980 Diag(D.getIdentifierLoc(), 2981 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2982 New->setInvalidDecl(); 2983 } 2984 2985 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2986 if (D.getCXXScopeSpec().isSet()) { 2987 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2988 << D.getCXXScopeSpec().getRange(); 2989 New->setInvalidDecl(); 2990 } 2991 2992 // Add the parameter declaration into this scope. 2993 S->AddDecl(DeclPtrTy::make(New)); 2994 if (II) 2995 IdResolver.AddDecl(New); 2996 2997 ProcessDeclAttributes(S, New, D); 2998 2999 if (New->hasAttr<BlocksAttr>()) { 3000 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3001 } 3002 return DeclPtrTy::make(New); 3003} 3004 3005void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3006 SourceLocation LocAfterDecls) { 3007 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3008 "Not a function declarator!"); 3009 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3010 3011 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3012 // for a K&R function. 3013 if (!FTI.hasPrototype) { 3014 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3015 --i; 3016 if (FTI.ArgInfo[i].Param == 0) { 3017 std::string Code = " int "; 3018 Code += FTI.ArgInfo[i].Ident->getName(); 3019 Code += ";\n"; 3020 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3021 << FTI.ArgInfo[i].Ident 3022 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3023 3024 // Implicitly declare the argument as type 'int' for lack of a better 3025 // type. 3026 DeclSpec DS; 3027 const char* PrevSpec; // unused 3028 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3029 PrevSpec); 3030 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3031 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3032 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3033 } 3034 } 3035 } 3036} 3037 3038Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3039 Declarator &D) { 3040 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3041 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3042 "Not a function declarator!"); 3043 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3044 3045 if (FTI.hasPrototype) { 3046 // FIXME: Diagnose arguments without names in C. 3047 } 3048 3049 Scope *ParentScope = FnBodyScope->getParent(); 3050 3051 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3052 MultiTemplateParamsArg(*this), 3053 /*IsFunctionDefinition=*/true); 3054 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3055} 3056 3057Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3058 if (!D) 3059 return D; 3060 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 3061 3062 CurFunctionNeedsScopeChecking = false; 3063 3064 // See if this is a redefinition. 3065 const FunctionDecl *Definition; 3066 if (FD->getBody(Definition)) { 3067 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3068 Diag(Definition->getLocation(), diag::note_previous_definition); 3069 } 3070 3071 // Builtin functions cannot be defined. 3072 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3073 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3074 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3075 FD->setInvalidDecl(); 3076 } 3077 } 3078 3079 // The return type of a function definition must be complete 3080 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3081 QualType ResultType = FD->getResultType(); 3082 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3083 !FD->isInvalidDecl() && 3084 RequireCompleteType(FD->getLocation(), ResultType, 3085 diag::err_func_def_incomplete_result)) 3086 FD->setInvalidDecl(); 3087 3088 // GNU warning -Wmissing-prototypes: 3089 // Warn if a global function is defined without a previous 3090 // prototype declaration. This warning is issued even if the 3091 // definition itself provides a prototype. The aim is to detect 3092 // global functions that fail to be declared in header files. 3093 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3094 !FD->isMain()) { 3095 bool MissingPrototype = true; 3096 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3097 Prev; Prev = Prev->getPreviousDeclaration()) { 3098 // Ignore any declarations that occur in function or method 3099 // scope, because they aren't visible from the header. 3100 if (Prev->getDeclContext()->isFunctionOrMethod()) 3101 continue; 3102 3103 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3104 break; 3105 } 3106 3107 if (MissingPrototype) 3108 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3109 } 3110 3111 if (FnBodyScope) 3112 PushDeclContext(FnBodyScope, FD); 3113 3114 // Check the validity of our function parameters 3115 CheckParmsForFunctionDef(FD); 3116 3117 // Introduce our parameters into the function scope 3118 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3119 ParmVarDecl *Param = FD->getParamDecl(p); 3120 Param->setOwningFunction(FD); 3121 3122 // If this has an identifier, add it to the scope stack. 3123 if (Param->getIdentifier() && FnBodyScope) 3124 PushOnScopeChains(Param, FnBodyScope); 3125 } 3126 3127 // Checking attributes of current function definition 3128 // dllimport attribute. 3129 if (FD->getAttr<DLLImportAttr>() && 3130 (!FD->getAttr<DLLExportAttr>())) { 3131 // dllimport attribute cannot be applied to definition. 3132 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3133 Diag(FD->getLocation(), 3134 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3135 << "dllimport"; 3136 FD->setInvalidDecl(); 3137 return DeclPtrTy::make(FD); 3138 } else { 3139 // If a symbol previously declared dllimport is later defined, the 3140 // attribute is ignored in subsequent references, and a warning is 3141 // emitted. 3142 Diag(FD->getLocation(), 3143 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3144 << FD->getNameAsCString() << "dllimport"; 3145 } 3146 } 3147 return DeclPtrTy::make(FD); 3148} 3149 3150Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3151 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3152} 3153 3154Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3155 bool IsInstantiation) { 3156 Decl *dcl = D.getAs<Decl>(); 3157 Stmt *Body = BodyArg.takeAs<Stmt>(); 3158 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3159 FD->setBody(Body); 3160 3161 if (!FD->isInvalidDecl()) 3162 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3163 3164 // C++ [basic.def.odr]p2: 3165 // [...] A virtual member function is used if it is not pure. [...] 3166 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3167 if (Method->isVirtual() && !Method->isPure()) 3168 MarkDeclarationReferenced(Method->getLocation(), Method); 3169 3170 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3171 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3172 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3173 MD->setBody(Body); 3174 3175 if (!MD->isInvalidDecl()) 3176 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3177 } else { 3178 Body->Destroy(Context); 3179 return DeclPtrTy(); 3180 } 3181 if (!IsInstantiation) 3182 PopDeclContext(); 3183 3184 // Verify and clean out per-function state. 3185 3186 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3187 3188 // Check goto/label use. 3189 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3190 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3191 LabelStmt *L = I->second; 3192 3193 // Verify that we have no forward references left. If so, there was a goto 3194 // or address of a label taken, but no definition of it. Label fwd 3195 // definitions are indicated with a null substmt. 3196 if (L->getSubStmt() != 0) 3197 continue; 3198 3199 // Emit error. 3200 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3201 3202 // At this point, we have gotos that use the bogus label. Stitch it into 3203 // the function body so that they aren't leaked and that the AST is well 3204 // formed. 3205 if (Body == 0) { 3206 // The whole function wasn't parsed correctly, just delete this. 3207 L->Destroy(Context); 3208 continue; 3209 } 3210 3211 // Otherwise, the body is valid: we want to stitch the label decl into the 3212 // function somewhere so that it is properly owned and so that the goto 3213 // has a valid target. Do this by creating a new compound stmt with the 3214 // label in it. 3215 3216 // Give the label a sub-statement. 3217 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3218 3219 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3220 cast<CXXTryStmt>(Body)->getTryBlock() : 3221 cast<CompoundStmt>(Body); 3222 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3223 Elements.push_back(L); 3224 Compound->setStmts(Context, &Elements[0], Elements.size()); 3225 } 3226 FunctionLabelMap.clear(); 3227 3228 if (!Body) return D; 3229 3230 // Verify that that gotos and switch cases don't jump into scopes illegally. 3231 if (CurFunctionNeedsScopeChecking) 3232 DiagnoseInvalidJumps(Body); 3233 3234 // C++ constructors that have function-try-blocks can't have return statements 3235 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3236 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3237 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3238 3239 return D; 3240} 3241 3242/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3243/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3244NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3245 IdentifierInfo &II, Scope *S) { 3246 // Before we produce a declaration for an implicitly defined 3247 // function, see whether there was a locally-scoped declaration of 3248 // this name as a function or variable. If so, use that 3249 // (non-visible) declaration, and complain about it. 3250 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3251 = LocallyScopedExternalDecls.find(&II); 3252 if (Pos != LocallyScopedExternalDecls.end()) { 3253 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3254 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3255 return Pos->second; 3256 } 3257 3258 // Extension in C99. Legal in C90, but warn about it. 3259 if (getLangOptions().C99) 3260 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3261 else 3262 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3263 3264 // FIXME: handle stuff like: 3265 // void foo() { extern float X(); } 3266 // void bar() { X(); } <-- implicit decl for X in another scope. 3267 3268 // Set a Declarator for the implicit definition: int foo(); 3269 const char *Dummy; 3270 DeclSpec DS; 3271 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3272 Error = Error; // Silence warning. 3273 assert(!Error && "Error setting up implicit decl!"); 3274 Declarator D(DS, Declarator::BlockContext); 3275 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3276 0, 0, false, SourceLocation(), 3277 false, 0,0,0, Loc, D), 3278 SourceLocation()); 3279 D.SetIdentifier(&II, Loc); 3280 3281 // Insert this function into translation-unit scope. 3282 3283 DeclContext *PrevDC = CurContext; 3284 CurContext = Context.getTranslationUnitDecl(); 3285 3286 FunctionDecl *FD = 3287 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3288 FD->setImplicit(); 3289 3290 CurContext = PrevDC; 3291 3292 AddKnownFunctionAttributes(FD); 3293 3294 return FD; 3295} 3296 3297/// \brief Adds any function attributes that we know a priori based on 3298/// the declaration of this function. 3299/// 3300/// These attributes can apply both to implicitly-declared builtins 3301/// (like __builtin___printf_chk) or to library-declared functions 3302/// like NSLog or printf. 3303void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3304 if (FD->isInvalidDecl()) 3305 return; 3306 3307 // If this is a built-in function, map its builtin attributes to 3308 // actual attributes. 3309 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3310 // Handle printf-formatting attributes. 3311 unsigned FormatIdx; 3312 bool HasVAListArg; 3313 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3314 if (!FD->getAttr<FormatAttr>()) 3315 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3316 HasVAListArg ? 0 : FormatIdx + 2)); 3317 } 3318 3319 // Mark const if we don't care about errno and that is the only 3320 // thing preventing the function from being const. This allows 3321 // IRgen to use LLVM intrinsics for such functions. 3322 if (!getLangOptions().MathErrno && 3323 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3324 if (!FD->getAttr<ConstAttr>()) 3325 FD->addAttr(::new (Context) ConstAttr()); 3326 } 3327 } 3328 3329 IdentifierInfo *Name = FD->getIdentifier(); 3330 if (!Name) 3331 return; 3332 if ((!getLangOptions().CPlusPlus && 3333 FD->getDeclContext()->isTranslationUnit()) || 3334 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3335 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3336 LinkageSpecDecl::lang_c)) { 3337 // Okay: this could be a libc/libm/Objective-C function we know 3338 // about. 3339 } else 3340 return; 3341 3342 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3343 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3344 // FIXME: We known better than our headers. 3345 const_cast<FormatAttr *>(Format)->setType("printf"); 3346 } else 3347 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3348 Name->isStr("NSLogv") ? 0 : 2)); 3349 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3350 if (!FD->getAttr<FormatAttr>()) 3351 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3352 Name->isStr("vasprintf") ? 0 : 3)); 3353 } 3354} 3355 3356TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3357 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3358 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3359 3360 // Scope manipulation handled by caller. 3361 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3362 D.getIdentifierLoc(), 3363 D.getIdentifier(), 3364 T); 3365 3366 if (TagType *TT = dyn_cast<TagType>(T)) { 3367 TagDecl *TD = TT->getDecl(); 3368 3369 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3370 // keep track of the TypedefDecl. 3371 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3372 TD->setTypedefForAnonDecl(NewTD); 3373 } 3374 3375 if (D.isInvalidType()) 3376 NewTD->setInvalidDecl(); 3377 return NewTD; 3378} 3379 3380 3381/// \brief Determine whether a tag with a given kind is acceptable 3382/// as a redeclaration of the given tag declaration. 3383/// 3384/// \returns true if the new tag kind is acceptable, false otherwise. 3385bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3386 TagDecl::TagKind NewTag, 3387 SourceLocation NewTagLoc, 3388 const IdentifierInfo &Name) { 3389 // C++ [dcl.type.elab]p3: 3390 // The class-key or enum keyword present in the 3391 // elaborated-type-specifier shall agree in kind with the 3392 // declaration to which the name in theelaborated-type-specifier 3393 // refers. This rule also applies to the form of 3394 // elaborated-type-specifier that declares a class-name or 3395 // friend class since it can be construed as referring to the 3396 // definition of the class. Thus, in any 3397 // elaborated-type-specifier, the enum keyword shall be used to 3398 // refer to an enumeration (7.2), the union class-keyshall be 3399 // used to refer to a union (clause 9), and either the class or 3400 // struct class-key shall be used to refer to a class (clause 9) 3401 // declared using the class or struct class-key. 3402 TagDecl::TagKind OldTag = Previous->getTagKind(); 3403 if (OldTag == NewTag) 3404 return true; 3405 3406 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3407 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3408 // Warn about the struct/class tag mismatch. 3409 bool isTemplate = false; 3410 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3411 isTemplate = Record->getDescribedClassTemplate(); 3412 3413 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3414 << (NewTag == TagDecl::TK_class) 3415 << isTemplate << &Name 3416 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3417 OldTag == TagDecl::TK_class? "class" : "struct"); 3418 Diag(Previous->getLocation(), diag::note_previous_use); 3419 return true; 3420 } 3421 return false; 3422} 3423 3424/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3425/// former case, Name will be non-null. In the later case, Name will be null. 3426/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3427/// reference/declaration/definition of a tag. 3428Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3429 SourceLocation KWLoc, const CXXScopeSpec &SS, 3430 IdentifierInfo *Name, SourceLocation NameLoc, 3431 AttributeList *Attr, AccessSpecifier AS, 3432 bool &OwnedDecl) { 3433 // If this is not a definition, it must have a name. 3434 assert((Name != 0 || TK == TK_Definition) && 3435 "Nameless record must be a definition!"); 3436 3437 OwnedDecl = false; 3438 TagDecl::TagKind Kind; 3439 switch (TagSpec) { 3440 default: assert(0 && "Unknown tag type!"); 3441 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3442 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3443 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3444 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3445 } 3446 3447 DeclContext *SearchDC = CurContext; 3448 DeclContext *DC = CurContext; 3449 NamedDecl *PrevDecl = 0; 3450 3451 bool Invalid = false; 3452 3453 if (Name && SS.isNotEmpty()) { 3454 // We have a nested-name tag ('struct foo::bar'). 3455 3456 // Check for invalid 'foo::'. 3457 if (SS.isInvalid()) { 3458 Name = 0; 3459 goto CreateNewDecl; 3460 } 3461 3462 if (RequireCompleteDeclContext(SS)) 3463 return DeclPtrTy::make((Decl *)0); 3464 3465 DC = computeDeclContext(SS); 3466 SearchDC = DC; 3467 // Look-up name inside 'foo::'. 3468 PrevDecl 3469 = dyn_cast_or_null<TagDecl>( 3470 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3471 3472 // A tag 'foo::bar' must already exist. 3473 if (PrevDecl == 0) { 3474 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3475 Name = 0; 3476 Invalid = true; 3477 goto CreateNewDecl; 3478 } 3479 } else if (Name) { 3480 // If this is a named struct, check to see if there was a previous forward 3481 // declaration or definition. 3482 // FIXME: We're looking into outer scopes here, even when we 3483 // shouldn't be. Doing so can result in ambiguities that we 3484 // shouldn't be diagnosing. 3485 LookupResult R = LookupName(S, Name, LookupTagName, 3486 /*RedeclarationOnly=*/(TK != TK_Reference)); 3487 if (R.isAmbiguous()) { 3488 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3489 // FIXME: This is not best way to recover from case like: 3490 // 3491 // struct S s; 3492 // 3493 // causes needless "incomplete type" error later. 3494 Name = 0; 3495 PrevDecl = 0; 3496 Invalid = true; 3497 } 3498 else 3499 PrevDecl = R; 3500 3501 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3502 // FIXME: This makes sure that we ignore the contexts associated 3503 // with C structs, unions, and enums when looking for a matching 3504 // tag declaration or definition. See the similar lookup tweak 3505 // in Sema::LookupName; is there a better way to deal with this? 3506 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3507 SearchDC = SearchDC->getParent(); 3508 } 3509 } 3510 3511 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3512 // Maybe we will complain about the shadowed template parameter. 3513 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3514 // Just pretend that we didn't see the previous declaration. 3515 PrevDecl = 0; 3516 } 3517 3518 if (PrevDecl) { 3519 // Check whether the previous declaration is usable. 3520 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3521 3522 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3523 // If this is a use of a previous tag, or if the tag is already declared 3524 // in the same scope (so that the definition/declaration completes or 3525 // rementions the tag), reuse the decl. 3526 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3527 // Make sure that this wasn't declared as an enum and now used as a 3528 // struct or something similar. 3529 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3530 bool SafeToContinue 3531 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3532 Kind != TagDecl::TK_enum); 3533 if (SafeToContinue) 3534 Diag(KWLoc, diag::err_use_with_wrong_tag) 3535 << Name 3536 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3537 PrevTagDecl->getKindName()); 3538 else 3539 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3540 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3541 3542 if (SafeToContinue) 3543 Kind = PrevTagDecl->getTagKind(); 3544 else { 3545 // Recover by making this an anonymous redefinition. 3546 Name = 0; 3547 PrevDecl = 0; 3548 Invalid = true; 3549 } 3550 } 3551 3552 if (!Invalid) { 3553 // If this is a use, just return the declaration we found. 3554 3555 // FIXME: In the future, return a variant or some other clue 3556 // for the consumer of this Decl to know it doesn't own it. 3557 // For our current ASTs this shouldn't be a problem, but will 3558 // need to be changed with DeclGroups. 3559 if (TK == TK_Reference) 3560 return DeclPtrTy::make(PrevDecl); 3561 3562 // Diagnose attempts to redefine a tag. 3563 if (TK == TK_Definition) { 3564 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3565 Diag(NameLoc, diag::err_redefinition) << Name; 3566 Diag(Def->getLocation(), diag::note_previous_definition); 3567 // If this is a redefinition, recover by making this 3568 // struct be anonymous, which will make any later 3569 // references get the previous definition. 3570 Name = 0; 3571 PrevDecl = 0; 3572 Invalid = true; 3573 } else { 3574 // If the type is currently being defined, complain 3575 // about a nested redefinition. 3576 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3577 if (Tag->isBeingDefined()) { 3578 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3579 Diag(PrevTagDecl->getLocation(), 3580 diag::note_previous_definition); 3581 Name = 0; 3582 PrevDecl = 0; 3583 Invalid = true; 3584 } 3585 } 3586 3587 // Okay, this is definition of a previously declared or referenced 3588 // tag PrevDecl. We're going to create a new Decl for it. 3589 } 3590 } 3591 // If we get here we have (another) forward declaration or we 3592 // have a definition. Just create a new decl. 3593 } else { 3594 // If we get here, this is a definition of a new tag type in a nested 3595 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3596 // new decl/type. We set PrevDecl to NULL so that the entities 3597 // have distinct types. 3598 PrevDecl = 0; 3599 } 3600 // If we get here, we're going to create a new Decl. If PrevDecl 3601 // is non-NULL, it's a definition of the tag declared by 3602 // PrevDecl. If it's NULL, we have a new definition. 3603 } else { 3604 // PrevDecl is a namespace, template, or anything else 3605 // that lives in the IDNS_Tag identifier namespace. 3606 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3607 // The tag name clashes with a namespace name, issue an error and 3608 // recover by making this tag be anonymous. 3609 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3610 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3611 Name = 0; 3612 PrevDecl = 0; 3613 Invalid = true; 3614 } else { 3615 // The existing declaration isn't relevant to us; we're in a 3616 // new scope, so clear out the previous declaration. 3617 PrevDecl = 0; 3618 } 3619 } 3620 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3621 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3622 // C++ [basic.scope.pdecl]p5: 3623 // -- for an elaborated-type-specifier of the form 3624 // 3625 // class-key identifier 3626 // 3627 // if the elaborated-type-specifier is used in the 3628 // decl-specifier-seq or parameter-declaration-clause of a 3629 // function defined in namespace scope, the identifier is 3630 // declared as a class-name in the namespace that contains 3631 // the declaration; otherwise, except as a friend 3632 // declaration, the identifier is declared in the smallest 3633 // non-class, non-function-prototype scope that contains the 3634 // declaration. 3635 // 3636 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3637 // C structs and unions. 3638 // 3639 // GNU C also supports this behavior as part of its incomplete 3640 // enum types extension, while GNU C++ does not. 3641 // 3642 // Find the context where we'll be declaring the tag. 3643 // FIXME: We would like to maintain the current DeclContext as the 3644 // lexical context, 3645 while (SearchDC->isRecord()) 3646 SearchDC = SearchDC->getParent(); 3647 3648 // Find the scope where we'll be declaring the tag. 3649 while (S->isClassScope() || 3650 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3651 ((S->getFlags() & Scope::DeclScope) == 0) || 3652 (S->getEntity() && 3653 ((DeclContext *)S->getEntity())->isTransparentContext())) 3654 S = S->getParent(); 3655 } 3656 3657CreateNewDecl: 3658 3659 // If there is an identifier, use the location of the identifier as the 3660 // location of the decl, otherwise use the location of the struct/union 3661 // keyword. 3662 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3663 3664 // Otherwise, create a new declaration. If there is a previous 3665 // declaration of the same entity, the two will be linked via 3666 // PrevDecl. 3667 TagDecl *New; 3668 3669 if (Kind == TagDecl::TK_enum) { 3670 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3671 // enum X { A, B, C } D; D should chain to X. 3672 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3673 cast_or_null<EnumDecl>(PrevDecl)); 3674 // If this is an undefined enum, warn. 3675 if (TK != TK_Definition && !Invalid) { 3676 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3677 : diag::ext_forward_ref_enum; 3678 Diag(Loc, DK); 3679 } 3680 } else { 3681 // struct/union/class 3682 3683 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3684 // struct X { int A; } D; D should chain to X. 3685 if (getLangOptions().CPlusPlus) 3686 // FIXME: Look for a way to use RecordDecl for simple structs. 3687 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3688 cast_or_null<CXXRecordDecl>(PrevDecl)); 3689 else 3690 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3691 cast_or_null<RecordDecl>(PrevDecl)); 3692 } 3693 3694 if (Kind != TagDecl::TK_enum) { 3695 // Handle #pragma pack: if the #pragma pack stack has non-default 3696 // alignment, make up a packed attribute for this decl. These 3697 // attributes are checked when the ASTContext lays out the 3698 // structure. 3699 // 3700 // It is important for implementing the correct semantics that this 3701 // happen here (in act on tag decl). The #pragma pack stack is 3702 // maintained as a result of parser callbacks which can occur at 3703 // many points during the parsing of a struct declaration (because 3704 // the #pragma tokens are effectively skipped over during the 3705 // parsing of the struct). 3706 if (unsigned Alignment = getPragmaPackAlignment()) 3707 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3708 } 3709 3710 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3711 // C++ [dcl.typedef]p3: 3712 // [...] Similarly, in a given scope, a class or enumeration 3713 // shall not be declared with the same name as a typedef-name 3714 // that is declared in that scope and refers to a type other 3715 // than the class or enumeration itself. 3716 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3717 TypedefDecl *PrevTypedef = 0; 3718 if (Lookup.getKind() == LookupResult::Found) 3719 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3720 3721 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3722 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3723 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3724 Diag(Loc, diag::err_tag_definition_of_typedef) 3725 << Context.getTypeDeclType(New) 3726 << PrevTypedef->getUnderlyingType(); 3727 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3728 Invalid = true; 3729 } 3730 } 3731 3732 if (Invalid) 3733 New->setInvalidDecl(); 3734 3735 if (Attr) 3736 ProcessDeclAttributeList(S, New, Attr); 3737 3738 // If we're declaring or defining a tag in function prototype scope 3739 // in C, note that this type can only be used within the function. 3740 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3741 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3742 3743 // Set the lexical context. If the tag has a C++ scope specifier, the 3744 // lexical context will be different from the semantic context. 3745 New->setLexicalDeclContext(CurContext); 3746 3747 // Set the access specifier. 3748 if (!Invalid) 3749 SetMemberAccessSpecifier(New, PrevDecl, AS); 3750 3751 if (TK == TK_Definition) 3752 New->startDefinition(); 3753 3754 // If this has an identifier, add it to the scope stack. 3755 if (Name) { 3756 S = getNonFieldDeclScope(S); 3757 PushOnScopeChains(New, S); 3758 } else { 3759 CurContext->addDecl(Context, New); 3760 } 3761 3762 OwnedDecl = true; 3763 return DeclPtrTy::make(New); 3764} 3765 3766void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3767 AdjustDeclIfTemplate(TagD); 3768 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3769 3770 // Enter the tag context. 3771 PushDeclContext(S, Tag); 3772 3773 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3774 FieldCollector->StartClass(); 3775 3776 if (Record->getIdentifier()) { 3777 // C++ [class]p2: 3778 // [...] The class-name is also inserted into the scope of the 3779 // class itself; this is known as the injected-class-name. For 3780 // purposes of access checking, the injected-class-name is treated 3781 // as if it were a public member name. 3782 CXXRecordDecl *InjectedClassName 3783 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3784 CurContext, Record->getLocation(), 3785 Record->getIdentifier(), Record); 3786 InjectedClassName->setImplicit(); 3787 InjectedClassName->setAccess(AS_public); 3788 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3789 InjectedClassName->setDescribedClassTemplate(Template); 3790 PushOnScopeChains(InjectedClassName, S); 3791 assert(InjectedClassName->isInjectedClassName() && 3792 "Broken injected-class-name"); 3793 } 3794 } 3795} 3796 3797void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3798 AdjustDeclIfTemplate(TagD); 3799 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3800 3801 if (isa<CXXRecordDecl>(Tag)) 3802 FieldCollector->FinishClass(); 3803 3804 // Exit this scope of this tag's definition. 3805 PopDeclContext(); 3806 3807 // Notify the consumer that we've defined a tag. 3808 Consumer.HandleTagDeclDefinition(Tag); 3809} 3810 3811// Note that FieldName may be null for anonymous bitfields. 3812bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3813 QualType FieldTy, const Expr *BitWidth) { 3814 3815 // C99 6.7.2.1p4 - verify the field type. 3816 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3817 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3818 // Handle incomplete types with specific error. 3819 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3820 return true; 3821 if (FieldName) 3822 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3823 << FieldName << FieldTy << BitWidth->getSourceRange(); 3824 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3825 << FieldTy << BitWidth->getSourceRange(); 3826 } 3827 3828 // If the bit-width is type- or value-dependent, don't try to check 3829 // it now. 3830 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3831 return false; 3832 3833 llvm::APSInt Value; 3834 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3835 return true; 3836 3837 // Zero-width bitfield is ok for anonymous field. 3838 if (Value == 0 && FieldName) 3839 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3840 3841 if (Value.isSigned() && Value.isNegative()) { 3842 if (FieldName) 3843 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3844 << FieldName << Value.toString(10); 3845 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3846 << Value.toString(10); 3847 } 3848 3849 if (!FieldTy->isDependentType()) { 3850 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3851 if (Value.getZExtValue() > TypeSize) { 3852 if (FieldName) 3853 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3854 << FieldName << (unsigned)TypeSize; 3855 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3856 << (unsigned)TypeSize; 3857 } 3858 } 3859 3860 return false; 3861} 3862 3863/// ActOnField - Each field of a struct/union/class is passed into this in order 3864/// to create a FieldDecl object for it. 3865Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3866 SourceLocation DeclStart, 3867 Declarator &D, ExprTy *BitfieldWidth) { 3868 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3869 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3870 AS_public); 3871 return DeclPtrTy::make(Res); 3872} 3873 3874/// HandleField - Analyze a field of a C struct or a C++ data member. 3875/// 3876FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3877 SourceLocation DeclStart, 3878 Declarator &D, Expr *BitWidth, 3879 AccessSpecifier AS) { 3880 IdentifierInfo *II = D.getIdentifier(); 3881 SourceLocation Loc = DeclStart; 3882 if (II) Loc = D.getIdentifierLoc(); 3883 3884 QualType T = GetTypeForDeclarator(D, S); 3885 if (getLangOptions().CPlusPlus) 3886 CheckExtraCXXDefaultArguments(D); 3887 3888 DiagnoseFunctionSpecifiers(D); 3889 3890 if (D.getDeclSpec().isThreadSpecified()) 3891 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3892 3893 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3894 3895 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3896 // Maybe we will complain about the shadowed template parameter. 3897 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3898 // Just pretend that we didn't see the previous declaration. 3899 PrevDecl = 0; 3900 } 3901 3902 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3903 PrevDecl = 0; 3904 3905 FieldDecl *NewFD 3906 = CheckFieldDecl(II, T, Record, Loc, 3907 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3908 BitWidth, AS, PrevDecl, &D); 3909 if (NewFD->isInvalidDecl() && PrevDecl) { 3910 // Don't introduce NewFD into scope; there's already something 3911 // with the same name in the same scope. 3912 } else if (II) { 3913 PushOnScopeChains(NewFD, S); 3914 } else 3915 Record->addDecl(Context, NewFD); 3916 3917 return NewFD; 3918} 3919 3920/// \brief Build a new FieldDecl and check its well-formedness. 3921/// 3922/// This routine builds a new FieldDecl given the fields name, type, 3923/// record, etc. \p PrevDecl should refer to any previous declaration 3924/// with the same name and in the same scope as the field to be 3925/// created. 3926/// 3927/// \returns a new FieldDecl. 3928/// 3929/// \todo The Declarator argument is a hack. It will be removed once 3930FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3931 RecordDecl *Record, SourceLocation Loc, 3932 bool Mutable, Expr *BitWidth, 3933 AccessSpecifier AS, NamedDecl *PrevDecl, 3934 Declarator *D) { 3935 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3936 bool InvalidDecl = false; 3937 if (D) InvalidDecl = D->isInvalidType(); 3938 3939 // If we receive a broken type, recover by assuming 'int' and 3940 // marking this declaration as invalid. 3941 if (T.isNull()) { 3942 InvalidDecl = true; 3943 T = Context.IntTy; 3944 } 3945 3946 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3947 // than a variably modified type. 3948 if (T->isVariablyModifiedType()) { 3949 bool SizeIsNegative; 3950 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3951 SizeIsNegative); 3952 if (!FixedTy.isNull()) { 3953 Diag(Loc, diag::warn_illegal_constant_array_size); 3954 T = FixedTy; 3955 } else { 3956 if (SizeIsNegative) 3957 Diag(Loc, diag::err_typecheck_negative_array_size); 3958 else 3959 Diag(Loc, diag::err_typecheck_field_variable_size); 3960 T = Context.IntTy; 3961 InvalidDecl = true; 3962 } 3963 } 3964 3965 // Fields can not have abstract class types 3966 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3967 AbstractFieldType)) 3968 InvalidDecl = true; 3969 3970 // If this is declared as a bit-field, check the bit-field. 3971 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3972 InvalidDecl = true; 3973 DeleteExpr(BitWidth); 3974 BitWidth = 0; 3975 } 3976 3977 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3978 Mutable); 3979 if (InvalidDecl) 3980 NewFD->setInvalidDecl(); 3981 3982 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3983 Diag(Loc, diag::err_duplicate_member) << II; 3984 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3985 NewFD->setInvalidDecl(); 3986 } 3987 3988 if (getLangOptions().CPlusPlus && !T->isPODType()) 3989 cast<CXXRecordDecl>(Record)->setPOD(false); 3990 3991 // FIXME: We need to pass in the attributes given an AST 3992 // representation, not a parser representation. 3993 if (D) 3994 // FIXME: What to pass instead of TUScope? 3995 ProcessDeclAttributes(TUScope, NewFD, *D); 3996 3997 if (T.isObjCGCWeak()) 3998 Diag(Loc, diag::warn_attribute_weak_on_field); 3999 4000 NewFD->setAccess(AS); 4001 4002 // C++ [dcl.init.aggr]p1: 4003 // An aggregate is an array or a class (clause 9) with [...] no 4004 // private or protected non-static data members (clause 11). 4005 // A POD must be an aggregate. 4006 if (getLangOptions().CPlusPlus && 4007 (AS == AS_private || AS == AS_protected)) { 4008 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4009 CXXRecord->setAggregate(false); 4010 CXXRecord->setPOD(false); 4011 } 4012 4013 return NewFD; 4014} 4015 4016/// TranslateIvarVisibility - Translate visibility from a token ID to an 4017/// AST enum value. 4018static ObjCIvarDecl::AccessControl 4019TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4020 switch (ivarVisibility) { 4021 default: assert(0 && "Unknown visitibility kind"); 4022 case tok::objc_private: return ObjCIvarDecl::Private; 4023 case tok::objc_public: return ObjCIvarDecl::Public; 4024 case tok::objc_protected: return ObjCIvarDecl::Protected; 4025 case tok::objc_package: return ObjCIvarDecl::Package; 4026 } 4027} 4028 4029/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4030/// in order to create an IvarDecl object for it. 4031Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4032 SourceLocation DeclStart, 4033 DeclPtrTy IntfDecl, 4034 Declarator &D, ExprTy *BitfieldWidth, 4035 tok::ObjCKeywordKind Visibility) { 4036 4037 IdentifierInfo *II = D.getIdentifier(); 4038 Expr *BitWidth = (Expr*)BitfieldWidth; 4039 SourceLocation Loc = DeclStart; 4040 if (II) Loc = D.getIdentifierLoc(); 4041 4042 // FIXME: Unnamed fields can be handled in various different ways, for 4043 // example, unnamed unions inject all members into the struct namespace! 4044 4045 QualType T = GetTypeForDeclarator(D, S); 4046 4047 if (BitWidth) { 4048 // 6.7.2.1p3, 6.7.2.1p4 4049 if (VerifyBitField(Loc, II, T, BitWidth)) { 4050 D.setInvalidType(); 4051 DeleteExpr(BitWidth); 4052 BitWidth = 0; 4053 } 4054 } else { 4055 // Not a bitfield. 4056 4057 // validate II. 4058 4059 } 4060 4061 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4062 // than a variably modified type. 4063 if (T->isVariablyModifiedType()) { 4064 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4065 D.setInvalidType(); 4066 } 4067 4068 // Get the visibility (access control) for this ivar. 4069 ObjCIvarDecl::AccessControl ac = 4070 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4071 : ObjCIvarDecl::None; 4072 // Must set ivar's DeclContext to its enclosing interface. 4073 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4074 DeclContext *EnclosingContext; 4075 if (ObjCImplementationDecl *IMPDecl = 4076 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4077 // Case of ivar declared in an implementation. Context is that of its class. 4078 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4079 assert(IDecl && "No class- ActOnIvar"); 4080 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4081 } 4082 else 4083 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4084 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4085 4086 // Construct the decl. 4087 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4088 EnclosingContext, Loc, II, T,ac, 4089 (Expr *)BitfieldWidth); 4090 4091 if (II) { 4092 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4093 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4094 && !isa<TagDecl>(PrevDecl)) { 4095 Diag(Loc, diag::err_duplicate_member) << II; 4096 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4097 NewID->setInvalidDecl(); 4098 } 4099 } 4100 4101 // Process attributes attached to the ivar. 4102 ProcessDeclAttributes(S, NewID, D); 4103 4104 if (D.isInvalidType()) 4105 NewID->setInvalidDecl(); 4106 4107 if (II) { 4108 // FIXME: When interfaces are DeclContexts, we'll need to add 4109 // these to the interface. 4110 S->AddDecl(DeclPtrTy::make(NewID)); 4111 IdResolver.AddDecl(NewID); 4112 } 4113 4114 return DeclPtrTy::make(NewID); 4115} 4116 4117void Sema::ActOnFields(Scope* S, 4118 SourceLocation RecLoc, DeclPtrTy RecDecl, 4119 DeclPtrTy *Fields, unsigned NumFields, 4120 SourceLocation LBrac, SourceLocation RBrac, 4121 AttributeList *Attr) { 4122 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4123 assert(EnclosingDecl && "missing record or interface decl"); 4124 4125 // If the decl this is being inserted into is invalid, then it may be a 4126 // redeclaration or some other bogus case. Don't try to add fields to it. 4127 if (EnclosingDecl->isInvalidDecl()) { 4128 // FIXME: Deallocate fields? 4129 return; 4130 } 4131 4132 4133 // Verify that all the fields are okay. 4134 unsigned NumNamedMembers = 0; 4135 llvm::SmallVector<FieldDecl*, 32> RecFields; 4136 4137 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4138 for (unsigned i = 0; i != NumFields; ++i) { 4139 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4140 4141 // Get the type for the field. 4142 Type *FDTy = FD->getType().getTypePtr(); 4143 4144 if (!FD->isAnonymousStructOrUnion()) { 4145 // Remember all fields written by the user. 4146 RecFields.push_back(FD); 4147 } 4148 4149 // If the field is already invalid for some reason, don't emit more 4150 // diagnostics about it. 4151 if (FD->isInvalidDecl()) 4152 continue; 4153 4154 // C99 6.7.2.1p2: 4155 // A structure or union shall not contain a member with 4156 // incomplete or function type (hence, a structure shall not 4157 // contain an instance of itself, but may contain a pointer to 4158 // an instance of itself), except that the last member of a 4159 // structure with more than one named member may have incomplete 4160 // array type; such a structure (and any union containing, 4161 // possibly recursively, a member that is such a structure) 4162 // shall not be a member of a structure or an element of an 4163 // array. 4164 if (FDTy->isFunctionType()) { 4165 // Field declared as a function. 4166 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4167 << FD->getDeclName(); 4168 FD->setInvalidDecl(); 4169 EnclosingDecl->setInvalidDecl(); 4170 continue; 4171 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4172 Record && Record->isStruct()) { 4173 // Flexible array member. 4174 if (NumNamedMembers < 1) { 4175 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4176 << FD->getDeclName(); 4177 FD->setInvalidDecl(); 4178 EnclosingDecl->setInvalidDecl(); 4179 continue; 4180 } 4181 // Okay, we have a legal flexible array member at the end of the struct. 4182 if (Record) 4183 Record->setHasFlexibleArrayMember(true); 4184 } else if (!FDTy->isDependentType() && 4185 RequireCompleteType(FD->getLocation(), FD->getType(), 4186 diag::err_field_incomplete)) { 4187 // Incomplete type 4188 FD->setInvalidDecl(); 4189 EnclosingDecl->setInvalidDecl(); 4190 continue; 4191 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4192 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4193 // If this is a member of a union, then entire union becomes "flexible". 4194 if (Record && Record->isUnion()) { 4195 Record->setHasFlexibleArrayMember(true); 4196 } else { 4197 // If this is a struct/class and this is not the last element, reject 4198 // it. Note that GCC supports variable sized arrays in the middle of 4199 // structures. 4200 if (i != NumFields-1) 4201 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4202 << FD->getDeclName() << FD->getType(); 4203 else { 4204 // We support flexible arrays at the end of structs in 4205 // other structs as an extension. 4206 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4207 << FD->getDeclName(); 4208 if (Record) 4209 Record->setHasFlexibleArrayMember(true); 4210 } 4211 } 4212 } 4213 } else if (FDTy->isObjCInterfaceType()) { 4214 /// A field cannot be an Objective-c object 4215 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4216 FD->setInvalidDecl(); 4217 EnclosingDecl->setInvalidDecl(); 4218 continue; 4219 } 4220 // Keep track of the number of named members. 4221 if (FD->getIdentifier()) 4222 ++NumNamedMembers; 4223 } 4224 4225 // Okay, we successfully defined 'Record'. 4226 if (Record) { 4227 Record->completeDefinition(Context); 4228 } else { 4229 ObjCIvarDecl **ClsFields = 4230 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4231 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4232 ID->setIVarList(ClsFields, RecFields.size(), Context); 4233 ID->setLocEnd(RBrac); 4234 // Add ivar's to class's DeclContext. 4235 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4236 ClsFields[i]->setLexicalDeclContext(ID); 4237 ID->addDecl(Context, ClsFields[i]); 4238 } 4239 // Must enforce the rule that ivars in the base classes may not be 4240 // duplicates. 4241 if (ID->getSuperClass()) { 4242 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4243 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4244 ObjCIvarDecl* Ivar = (*IVI); 4245 4246 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4247 ObjCIvarDecl* prevIvar = 4248 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4249 if (prevIvar) { 4250 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4251 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4252 } 4253 } 4254 } 4255 } 4256 } else if (ObjCImplementationDecl *IMPDecl = 4257 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4258 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4259 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4260 // Ivar declared in @implementation never belongs to the implementation. 4261 // Only it is in implementation's lexical context. 4262 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4263 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4264 } 4265 } 4266 4267 if (Attr) 4268 ProcessDeclAttributeList(S, Record, Attr); 4269} 4270 4271EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4272 EnumConstantDecl *LastEnumConst, 4273 SourceLocation IdLoc, 4274 IdentifierInfo *Id, 4275 ExprArg val) { 4276 Expr *Val = (Expr *)val.get(); 4277 4278 llvm::APSInt EnumVal(32); 4279 QualType EltTy; 4280 if (Val && !Val->isTypeDependent()) { 4281 // Make sure to promote the operand type to int. 4282 UsualUnaryConversions(Val); 4283 if (Val != val.get()) { 4284 val.release(); 4285 val = Val; 4286 } 4287 4288 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4289 SourceLocation ExpLoc; 4290 if (!Val->isValueDependent() && 4291 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4292 Val = 0; 4293 } else { 4294 EltTy = Val->getType(); 4295 } 4296 } 4297 4298 if (!Val) { 4299 if (LastEnumConst) { 4300 // Assign the last value + 1. 4301 EnumVal = LastEnumConst->getInitVal(); 4302 ++EnumVal; 4303 4304 // Check for overflow on increment. 4305 if (EnumVal < LastEnumConst->getInitVal()) 4306 Diag(IdLoc, diag::warn_enum_value_overflow); 4307 4308 EltTy = LastEnumConst->getType(); 4309 } else { 4310 // First value, set to zero. 4311 EltTy = Context.IntTy; 4312 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4313 } 4314 } 4315 4316 val.release(); 4317 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4318 Val, EnumVal); 4319} 4320 4321 4322Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4323 DeclPtrTy lastEnumConst, 4324 SourceLocation IdLoc, 4325 IdentifierInfo *Id, 4326 SourceLocation EqualLoc, ExprTy *val) { 4327 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4328 EnumConstantDecl *LastEnumConst = 4329 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4330 Expr *Val = static_cast<Expr*>(val); 4331 4332 // The scope passed in may not be a decl scope. Zip up the scope tree until 4333 // we find one that is. 4334 S = getNonFieldDeclScope(S); 4335 4336 // Verify that there isn't already something declared with this name in this 4337 // scope. 4338 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4339 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4340 // Maybe we will complain about the shadowed template parameter. 4341 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4342 // Just pretend that we didn't see the previous declaration. 4343 PrevDecl = 0; 4344 } 4345 4346 if (PrevDecl) { 4347 // When in C++, we may get a TagDecl with the same name; in this case the 4348 // enum constant will 'hide' the tag. 4349 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4350 "Received TagDecl when not in C++!"); 4351 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4352 if (isa<EnumConstantDecl>(PrevDecl)) 4353 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4354 else 4355 Diag(IdLoc, diag::err_redefinition) << Id; 4356 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4357 if (Val) Val->Destroy(Context); 4358 return DeclPtrTy(); 4359 } 4360 } 4361 4362 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4363 IdLoc, Id, Owned(Val)); 4364 4365 // Register this decl in the current scope stack. 4366 if (New) 4367 PushOnScopeChains(New, S); 4368 4369 return DeclPtrTy::make(New); 4370} 4371 4372void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 4373 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 4374 DeclPtrTy *Elements, unsigned NumElements) { 4375 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4376 QualType EnumType = Context.getTypeDeclType(Enum); 4377 4378 // TODO: If the result value doesn't fit in an int, it must be a long or long 4379 // long value. ISO C does not support this, but GCC does as an extension, 4380 // emit a warning. 4381 unsigned IntWidth = Context.Target.getIntWidth(); 4382 4383 // Verify that all the values are okay, compute the size of the values, and 4384 // reverse the list. 4385 unsigned NumNegativeBits = 0; 4386 unsigned NumPositiveBits = 0; 4387 4388 // Keep track of whether all elements have type int. 4389 bool AllElementsInt = true; 4390 4391 for (unsigned i = 0; i != NumElements; ++i) { 4392 EnumConstantDecl *ECD = 4393 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4394 if (!ECD) continue; // Already issued a diagnostic. 4395 4396 // If the enum value doesn't fit in an int, emit an extension warning. 4397 const llvm::APSInt &InitVal = ECD->getInitVal(); 4398 assert(InitVal.getBitWidth() >= IntWidth && 4399 "Should have promoted value to int"); 4400 if (InitVal.getBitWidth() > IntWidth) { 4401 llvm::APSInt V(InitVal); 4402 V.trunc(IntWidth); 4403 V.extend(InitVal.getBitWidth()); 4404 if (V != InitVal) 4405 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4406 << InitVal.toString(10); 4407 } 4408 4409 // Keep track of the size of positive and negative values. 4410 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4411 NumPositiveBits = std::max(NumPositiveBits, 4412 (unsigned)InitVal.getActiveBits()); 4413 else 4414 NumNegativeBits = std::max(NumNegativeBits, 4415 (unsigned)InitVal.getMinSignedBits()); 4416 4417 // Keep track of whether every enum element has type int (very commmon). 4418 if (AllElementsInt) 4419 AllElementsInt = ECD->getType() == Context.IntTy; 4420 } 4421 4422 // Figure out the type that should be used for this enum. 4423 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4424 QualType BestType; 4425 unsigned BestWidth; 4426 4427 if (NumNegativeBits) { 4428 // If there is a negative value, figure out the smallest integer type (of 4429 // int/long/longlong) that fits. 4430 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4431 BestType = Context.IntTy; 4432 BestWidth = IntWidth; 4433 } else { 4434 BestWidth = Context.Target.getLongWidth(); 4435 4436 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4437 BestType = Context.LongTy; 4438 else { 4439 BestWidth = Context.Target.getLongLongWidth(); 4440 4441 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4442 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4443 BestType = Context.LongLongTy; 4444 } 4445 } 4446 } else { 4447 // If there is no negative value, figure out which of uint, ulong, ulonglong 4448 // fits. 4449 if (NumPositiveBits <= IntWidth) { 4450 BestType = Context.UnsignedIntTy; 4451 BestWidth = IntWidth; 4452 } else if (NumPositiveBits <= 4453 (BestWidth = Context.Target.getLongWidth())) { 4454 BestType = Context.UnsignedLongTy; 4455 } else { 4456 BestWidth = Context.Target.getLongLongWidth(); 4457 assert(NumPositiveBits <= BestWidth && 4458 "How could an initializer get larger than ULL?"); 4459 BestType = Context.UnsignedLongLongTy; 4460 } 4461 } 4462 4463 // Loop over all of the enumerator constants, changing their types to match 4464 // the type of the enum if needed. 4465 for (unsigned i = 0; i != NumElements; ++i) { 4466 EnumConstantDecl *ECD = 4467 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4468 if (!ECD) continue; // Already issued a diagnostic. 4469 4470 // Standard C says the enumerators have int type, but we allow, as an 4471 // extension, the enumerators to be larger than int size. If each 4472 // enumerator value fits in an int, type it as an int, otherwise type it the 4473 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4474 // that X has type 'int', not 'unsigned'. 4475 if (ECD->getType() == Context.IntTy) { 4476 // Make sure the init value is signed. 4477 llvm::APSInt IV = ECD->getInitVal(); 4478 IV.setIsSigned(true); 4479 ECD->setInitVal(IV); 4480 4481 if (getLangOptions().CPlusPlus) 4482 // C++ [dcl.enum]p4: Following the closing brace of an 4483 // enum-specifier, each enumerator has the type of its 4484 // enumeration. 4485 ECD->setType(EnumType); 4486 continue; // Already int type. 4487 } 4488 4489 // Determine whether the value fits into an int. 4490 llvm::APSInt InitVal = ECD->getInitVal(); 4491 bool FitsInInt; 4492 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4493 FitsInInt = InitVal.getActiveBits() < IntWidth; 4494 else 4495 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4496 4497 // If it fits into an integer type, force it. Otherwise force it to match 4498 // the enum decl type. 4499 QualType NewTy; 4500 unsigned NewWidth; 4501 bool NewSign; 4502 if (FitsInInt) { 4503 NewTy = Context.IntTy; 4504 NewWidth = IntWidth; 4505 NewSign = true; 4506 } else if (ECD->getType() == BestType) { 4507 // Already the right type! 4508 if (getLangOptions().CPlusPlus) 4509 // C++ [dcl.enum]p4: Following the closing brace of an 4510 // enum-specifier, each enumerator has the type of its 4511 // enumeration. 4512 ECD->setType(EnumType); 4513 continue; 4514 } else { 4515 NewTy = BestType; 4516 NewWidth = BestWidth; 4517 NewSign = BestType->isSignedIntegerType(); 4518 } 4519 4520 // Adjust the APSInt value. 4521 InitVal.extOrTrunc(NewWidth); 4522 InitVal.setIsSigned(NewSign); 4523 ECD->setInitVal(InitVal); 4524 4525 // Adjust the Expr initializer and type. 4526 if (ECD->getInitExpr()) 4527 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4528 /*isLvalue=*/false)); 4529 if (getLangOptions().CPlusPlus) 4530 // C++ [dcl.enum]p4: Following the closing brace of an 4531 // enum-specifier, each enumerator has the type of its 4532 // enumeration. 4533 ECD->setType(EnumType); 4534 else 4535 ECD->setType(NewTy); 4536 } 4537 4538 Enum->completeDefinition(Context, BestType); 4539} 4540 4541Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4542 ExprArg expr) { 4543 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4544 4545 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 4546 Loc, AsmString); 4547 CurContext->addDecl(Context, New); 4548 return DeclPtrTy::make(New); 4549} 4550 4551void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 4552 SourceLocation PragmaLoc, 4553 SourceLocation NameLoc) { 4554 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4555 4556 // FIXME: This implementation is an ugly hack! 4557 if (PrevDecl) { 4558 PrevDecl->addAttr(::new (Context) WeakAttr()); 4559 return; 4560 } 4561 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4562 return; 4563} 4564 4565void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 4566 IdentifierInfo* AliasName, 4567 SourceLocation PragmaLoc, 4568 SourceLocation NameLoc, 4569 SourceLocation AliasNameLoc) { 4570 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4571 4572 // FIXME: This implementation is an ugly hack! 4573 if (PrevDecl) { 4574 PrevDecl->addAttr(::new (Context) AliasAttr(AliasName->getName())); 4575 PrevDecl->addAttr(::new (Context) WeakAttr()); 4576 return; 4577 } 4578 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4579 return; 4580} 4581