SemaDecl.cpp revision 25cf760b54d3b88633827501013bc51a29b28aba
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/Analysis/CFG.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Basic/PartialDiagnostic.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/Basic/TargetInfo.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/BitVector.h" 33#include "llvm/ADT/STLExtras.h" 34#include <algorithm> 35#include <functional> 36#include <queue> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, const CXXScopeSpec *SS, 65 bool isClassName) { 66 // C++ [temp.res]p3: 67 // A qualified-id that refers to a type and in which the 68 // nested-name-specifier depends on a template-parameter (14.6.2) 69 // shall be prefixed by the keyword typename to indicate that the 70 // qualified-id denotes a type, forming an 71 // elaborated-type-specifier (7.1.5.3). 72 // 73 // We therefore do not perform any name lookup if the result would 74 // refer to a member of an unknown specialization. 75 if (SS && isUnknownSpecialization(*SS)) { 76 if (!isClassName) 77 return 0; 78 79 // We know from the grammar that this name refers to a type, so build a 80 // TypenameType node to describe the type. 81 // FIXME: Record somewhere that this TypenameType node has no "typename" 82 // keyword associated with it. 83 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 84 II, SS->getRange()).getAsOpaquePtr(); 85 } 86 87 LookupResult Result 88 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 89 90 NamedDecl *IIDecl = 0; 91 switch (Result.getKind()) { 92 case LookupResult::NotFound: 93 case LookupResult::FoundOverloaded: 94 return 0; 95 96 case LookupResult::AmbiguousBaseSubobjectTypes: 97 case LookupResult::AmbiguousBaseSubobjects: 98 case LookupResult::AmbiguousReference: { 99 // Look to see if we have a type anywhere in the list of results. 100 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 101 Res != ResEnd; ++Res) { 102 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 103 if (!IIDecl || 104 (*Res)->getLocation().getRawEncoding() < 105 IIDecl->getLocation().getRawEncoding()) 106 IIDecl = *Res; 107 } 108 } 109 110 if (!IIDecl) { 111 // None of the entities we found is a type, so there is no way 112 // to even assume that the result is a type. In this case, don't 113 // complain about the ambiguity. The parser will either try to 114 // perform this lookup again (e.g., as an object name), which 115 // will produce the ambiguity, or will complain that it expected 116 // a type name. 117 Result.Destroy(); 118 return 0; 119 } 120 121 // We found a type within the ambiguous lookup; diagnose the 122 // ambiguity and then return that type. This might be the right 123 // answer, or it might not be, but it suppresses any attempt to 124 // perform the name lookup again. 125 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 126 break; 127 } 128 129 case LookupResult::Found: 130 IIDecl = Result.getAsDecl(); 131 break; 132 } 133 134 if (IIDecl) { 135 QualType T; 136 137 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 138 // Check whether we can use this type 139 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 140 141 if (getLangOptions().CPlusPlus) { 142 // C++ [temp.local]p2: 143 // Within the scope of a class template specialization or 144 // partial specialization, when the injected-class-name is 145 // not followed by a <, it is equivalent to the 146 // injected-class-name followed by the template-argument s 147 // of the class template specialization or partial 148 // specialization enclosed in <>. 149 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 150 if (RD->isInjectedClassName()) 151 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 152 T = Template->getInjectedClassNameType(Context); 153 } 154 155 if (T.isNull()) 156 T = Context.getTypeDeclType(TD); 157 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 158 // Check whether we can use this interface. 159 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 160 161 T = Context.getObjCInterfaceType(IDecl); 162 } else 163 return 0; 164 165 if (SS) 166 T = getQualifiedNameType(*SS, T); 167 168 return T.getAsOpaquePtr(); 169 } 170 171 return 0; 172} 173 174/// isTagName() - This method is called *for error recovery purposes only* 175/// to determine if the specified name is a valid tag name ("struct foo"). If 176/// so, this returns the TST for the tag corresponding to it (TST_enum, 177/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 178/// where the user forgot to specify the tag. 179DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 180 // Do a tag name lookup in this scope. 181 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 182 if (R.getKind() == LookupResult::Found) 183 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 184 switch (TD->getTagKind()) { 185 case TagDecl::TK_struct: return DeclSpec::TST_struct; 186 case TagDecl::TK_union: return DeclSpec::TST_union; 187 case TagDecl::TK_class: return DeclSpec::TST_class; 188 case TagDecl::TK_enum: return DeclSpec::TST_enum; 189 } 190 } 191 192 return DeclSpec::TST_unspecified; 193} 194 195 196// Determines the context to return to after temporarily entering a 197// context. This depends in an unnecessarily complicated way on the 198// exact ordering of callbacks from the parser. 199DeclContext *Sema::getContainingDC(DeclContext *DC) { 200 201 // Functions defined inline within classes aren't parsed until we've 202 // finished parsing the top-level class, so the top-level class is 203 // the context we'll need to return to. 204 if (isa<FunctionDecl>(DC)) { 205 DC = DC->getLexicalParent(); 206 207 // A function not defined within a class will always return to its 208 // lexical context. 209 if (!isa<CXXRecordDecl>(DC)) 210 return DC; 211 212 // A C++ inline method/friend is parsed *after* the topmost class 213 // it was declared in is fully parsed ("complete"); the topmost 214 // class is the context we need to return to. 215 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 216 DC = RD; 217 218 // Return the declaration context of the topmost class the inline method is 219 // declared in. 220 return DC; 221 } 222 223 if (isa<ObjCMethodDecl>(DC)) 224 return Context.getTranslationUnitDecl(); 225 226 return DC->getLexicalParent(); 227} 228 229void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 230 assert(getContainingDC(DC) == CurContext && 231 "The next DeclContext should be lexically contained in the current one."); 232 CurContext = DC; 233 S->setEntity(DC); 234} 235 236void Sema::PopDeclContext() { 237 assert(CurContext && "DeclContext imbalance!"); 238 239 CurContext = getContainingDC(CurContext); 240} 241 242/// EnterDeclaratorContext - Used when we must lookup names in the context 243/// of a declarator's nested name specifier. 244void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 245 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 246 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 247 CurContext = DC; 248 assert(CurContext && "No context?"); 249 S->setEntity(CurContext); 250} 251 252void Sema::ExitDeclaratorContext(Scope *S) { 253 S->setEntity(PreDeclaratorDC); 254 PreDeclaratorDC = 0; 255 256 // Reset CurContext to the nearest enclosing context. 257 while (!S->getEntity() && S->getParent()) 258 S = S->getParent(); 259 CurContext = static_cast<DeclContext*>(S->getEntity()); 260 assert(CurContext && "No context?"); 261} 262 263/// \brief Determine whether we allow overloading of the function 264/// PrevDecl with another declaration. 265/// 266/// This routine determines whether overloading is possible, not 267/// whether some new function is actually an overload. It will return 268/// true in C++ (where we can always provide overloads) or, as an 269/// extension, in C when the previous function is already an 270/// overloaded function declaration or has the "overloadable" 271/// attribute. 272static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 273 if (Context.getLangOptions().CPlusPlus) 274 return true; 275 276 if (isa<OverloadedFunctionDecl>(PrevDecl)) 277 return true; 278 279 return PrevDecl->getAttr<OverloadableAttr>() != 0; 280} 281 282/// Add this decl to the scope shadowed decl chains. 283void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 284 // Move up the scope chain until we find the nearest enclosing 285 // non-transparent context. The declaration will be introduced into this 286 // scope. 287 while (S->getEntity() && 288 ((DeclContext *)S->getEntity())->isTransparentContext()) 289 S = S->getParent(); 290 291 S->AddDecl(DeclPtrTy::make(D)); 292 293 // Add scoped declarations into their context, so that they can be 294 // found later. Declarations without a context won't be inserted 295 // into any context. 296 if (AddToContext) 297 CurContext->addDecl(D); 298 299 // C++ [basic.scope]p4: 300 // -- exactly one declaration shall declare a class name or 301 // enumeration name that is not a typedef name and the other 302 // declarations shall all refer to the same object or 303 // enumerator, or all refer to functions and function templates; 304 // in this case the class name or enumeration name is hidden. 305 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 306 // We are pushing the name of a tag (enum or class). 307 if (CurContext->getLookupContext() 308 == TD->getDeclContext()->getLookupContext()) { 309 // We're pushing the tag into the current context, which might 310 // require some reshuffling in the identifier resolver. 311 IdentifierResolver::iterator 312 I = IdResolver.begin(TD->getDeclName()), 313 IEnd = IdResolver.end(); 314 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 315 NamedDecl *PrevDecl = *I; 316 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 317 PrevDecl = *I, ++I) { 318 if (TD->declarationReplaces(*I)) { 319 // This is a redeclaration. Remove it from the chain and 320 // break out, so that we'll add in the shadowed 321 // declaration. 322 S->RemoveDecl(DeclPtrTy::make(*I)); 323 if (PrevDecl == *I) { 324 IdResolver.RemoveDecl(*I); 325 IdResolver.AddDecl(TD); 326 return; 327 } else { 328 IdResolver.RemoveDecl(*I); 329 break; 330 } 331 } 332 } 333 334 // There is already a declaration with the same name in the same 335 // scope, which is not a tag declaration. It must be found 336 // before we find the new declaration, so insert the new 337 // declaration at the end of the chain. 338 IdResolver.AddShadowedDecl(TD, PrevDecl); 339 340 return; 341 } 342 } 343 } else if ((isa<FunctionDecl>(D) && 344 AllowOverloadingOfFunction(D, Context)) || 345 isa<FunctionTemplateDecl>(D)) { 346 // We are pushing the name of a function or function template, 347 // which might be an overloaded name. 348 IdentifierResolver::iterator Redecl 349 = std::find_if(IdResolver.begin(D->getDeclName()), 350 IdResolver.end(), 351 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 352 D)); 353 if (Redecl != IdResolver.end() && 354 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 355 // There is already a declaration of a function on our 356 // IdResolver chain. Replace it with this declaration. 357 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 358 IdResolver.RemoveDecl(*Redecl); 359 } 360 } else if (isa<ObjCInterfaceDecl>(D)) { 361 // We're pushing an Objective-C interface into the current 362 // context. If there is already an alias declaration, remove it first. 363 for (IdentifierResolver::iterator 364 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 365 I != IEnd; ++I) { 366 if (isa<ObjCCompatibleAliasDecl>(*I)) { 367 S->RemoveDecl(DeclPtrTy::make(*I)); 368 IdResolver.RemoveDecl(*I); 369 break; 370 } 371 } 372 } 373 374 IdResolver.AddDecl(D); 375} 376 377void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 378 if (S->decl_empty()) return; 379 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 380 "Scope shouldn't contain decls!"); 381 382 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 383 I != E; ++I) { 384 Decl *TmpD = (*I).getAs<Decl>(); 385 assert(TmpD && "This decl didn't get pushed??"); 386 387 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 388 NamedDecl *D = cast<NamedDecl>(TmpD); 389 390 if (!D->getDeclName()) continue; 391 392 // Remove this name from our lexical scope. 393 IdResolver.RemoveDecl(D); 394 } 395} 396 397/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 398/// return 0 if one not found. 399ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 400 // The third "scope" argument is 0 since we aren't enabling lazy built-in 401 // creation from this context. 402 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 403 404 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 405} 406 407/// getNonFieldDeclScope - Retrieves the innermost scope, starting 408/// from S, where a non-field would be declared. This routine copes 409/// with the difference between C and C++ scoping rules in structs and 410/// unions. For example, the following code is well-formed in C but 411/// ill-formed in C++: 412/// @code 413/// struct S6 { 414/// enum { BAR } e; 415/// }; 416/// 417/// void test_S6() { 418/// struct S6 a; 419/// a.e = BAR; 420/// } 421/// @endcode 422/// For the declaration of BAR, this routine will return a different 423/// scope. The scope S will be the scope of the unnamed enumeration 424/// within S6. In C++, this routine will return the scope associated 425/// with S6, because the enumeration's scope is a transparent 426/// context but structures can contain non-field names. In C, this 427/// routine will return the translation unit scope, since the 428/// enumeration's scope is a transparent context and structures cannot 429/// contain non-field names. 430Scope *Sema::getNonFieldDeclScope(Scope *S) { 431 while (((S->getFlags() & Scope::DeclScope) == 0) || 432 (S->getEntity() && 433 ((DeclContext *)S->getEntity())->isTransparentContext()) || 434 (S->isClassScope() && !getLangOptions().CPlusPlus)) 435 S = S->getParent(); 436 return S; 437} 438 439void Sema::InitBuiltinVaListType() { 440 if (!Context.getBuiltinVaListType().isNull()) 441 return; 442 443 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 444 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 445 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 446 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 447} 448 449/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 450/// file scope. lazily create a decl for it. ForRedeclaration is true 451/// if we're creating this built-in in anticipation of redeclaring the 452/// built-in. 453NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 454 Scope *S, bool ForRedeclaration, 455 SourceLocation Loc) { 456 Builtin::ID BID = (Builtin::ID)bid; 457 458 if (Context.BuiltinInfo.hasVAListUse(BID)) 459 InitBuiltinVaListType(); 460 461 ASTContext::GetBuiltinTypeError Error; 462 QualType R = Context.GetBuiltinType(BID, Error); 463 switch (Error) { 464 case ASTContext::GE_None: 465 // Okay 466 break; 467 468 case ASTContext::GE_Missing_stdio: 469 if (ForRedeclaration) 470 Diag(Loc, diag::err_implicit_decl_requires_stdio) 471 << Context.BuiltinInfo.GetName(BID); 472 return 0; 473 474 case ASTContext::GE_Missing_setjmp: 475 if (ForRedeclaration) 476 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 477 << Context.BuiltinInfo.GetName(BID); 478 return 0; 479 } 480 481 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 482 Diag(Loc, diag::ext_implicit_lib_function_decl) 483 << Context.BuiltinInfo.GetName(BID) 484 << R; 485 if (Context.BuiltinInfo.getHeaderName(BID) && 486 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 487 != Diagnostic::Ignored) 488 Diag(Loc, diag::note_please_include_header) 489 << Context.BuiltinInfo.getHeaderName(BID) 490 << Context.BuiltinInfo.GetName(BID); 491 } 492 493 FunctionDecl *New = FunctionDecl::Create(Context, 494 Context.getTranslationUnitDecl(), 495 Loc, II, R, /*DInfo=*/0, 496 FunctionDecl::Extern, false, 497 /*hasPrototype=*/true); 498 New->setImplicit(); 499 500 // Create Decl objects for each parameter, adding them to the 501 // FunctionDecl. 502 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 503 llvm::SmallVector<ParmVarDecl*, 16> Params; 504 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 505 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 506 FT->getArgType(i), /*DInfo=*/0, 507 VarDecl::None, 0)); 508 New->setParams(Context, Params.data(), Params.size()); 509 } 510 511 AddKnownFunctionAttributes(New); 512 513 // TUScope is the translation-unit scope to insert this function into. 514 // FIXME: This is hideous. We need to teach PushOnScopeChains to 515 // relate Scopes to DeclContexts, and probably eliminate CurContext 516 // entirely, but we're not there yet. 517 DeclContext *SavedContext = CurContext; 518 CurContext = Context.getTranslationUnitDecl(); 519 PushOnScopeChains(New, TUScope); 520 CurContext = SavedContext; 521 return New; 522} 523 524/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 525/// everything from the standard library is defined. 526NamespaceDecl *Sema::GetStdNamespace() { 527 if (!StdNamespace) { 528 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 529 DeclContext *Global = Context.getTranslationUnitDecl(); 530 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 531 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 532 } 533 return StdNamespace; 534} 535 536/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 537/// same name and scope as a previous declaration 'Old'. Figure out 538/// how to resolve this situation, merging decls or emitting 539/// diagnostics as appropriate. If there was an error, set New to be invalid. 540/// 541void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 542 // If either decl is known invalid already, set the new one to be invalid and 543 // don't bother doing any merging checks. 544 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 545 return New->setInvalidDecl(); 546 547 // Allow multiple definitions for ObjC built-in typedefs. 548 // FIXME: Verify the underlying types are equivalent! 549 if (getLangOptions().ObjC1) { 550 const IdentifierInfo *TypeID = New->getIdentifier(); 551 switch (TypeID->getLength()) { 552 default: break; 553 case 2: 554 if (!TypeID->isStr("id")) 555 break; 556 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 557 // Install the built-in type for 'id', ignoring the current definition. 558 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 559 return; 560 case 5: 561 if (!TypeID->isStr("Class")) 562 break; 563 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 564 // Install the built-in type for 'Class', ignoring the current definition. 565 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 566 return; 567 case 3: 568 if (!TypeID->isStr("SEL")) 569 break; 570 Context.setObjCSelType(Context.getTypeDeclType(New)); 571 return; 572 case 8: 573 if (!TypeID->isStr("Protocol")) 574 break; 575 Context.setObjCProtoType(New->getUnderlyingType()); 576 return; 577 } 578 // Fall through - the typedef name was not a builtin type. 579 } 580 // Verify the old decl was also a type. 581 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 582 if (!Old) { 583 Diag(New->getLocation(), diag::err_redefinition_different_kind) 584 << New->getDeclName(); 585 if (OldD->getLocation().isValid()) 586 Diag(OldD->getLocation(), diag::note_previous_definition); 587 return New->setInvalidDecl(); 588 } 589 590 // Determine the "old" type we'll use for checking and diagnostics. 591 QualType OldType; 592 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 593 OldType = OldTypedef->getUnderlyingType(); 594 else 595 OldType = Context.getTypeDeclType(Old); 596 597 // If the typedef types are not identical, reject them in all languages and 598 // with any extensions enabled. 599 600 if (OldType != New->getUnderlyingType() && 601 Context.getCanonicalType(OldType) != 602 Context.getCanonicalType(New->getUnderlyingType())) { 603 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 604 << New->getUnderlyingType() << OldType; 605 if (Old->getLocation().isValid()) 606 Diag(Old->getLocation(), diag::note_previous_definition); 607 return New->setInvalidDecl(); 608 } 609 610 if (getLangOptions().Microsoft) 611 return; 612 613 // C++ [dcl.typedef]p2: 614 // In a given non-class scope, a typedef specifier can be used to 615 // redefine the name of any type declared in that scope to refer 616 // to the type to which it already refers. 617 if (getLangOptions().CPlusPlus) { 618 if (!isa<CXXRecordDecl>(CurContext)) 619 return; 620 Diag(New->getLocation(), diag::err_redefinition) 621 << New->getDeclName(); 622 Diag(Old->getLocation(), diag::note_previous_definition); 623 return New->setInvalidDecl(); 624 } 625 626 // If we have a redefinition of a typedef in C, emit a warning. This warning 627 // is normally mapped to an error, but can be controlled with 628 // -Wtypedef-redefinition. If either the original or the redefinition is 629 // in a system header, don't emit this for compatibility with GCC. 630 if (PP.getDiagnostics().getSuppressSystemWarnings() && 631 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 632 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 633 return; 634 635 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 636 << New->getDeclName(); 637 Diag(Old->getLocation(), diag::note_previous_definition); 638 return; 639} 640 641/// DeclhasAttr - returns true if decl Declaration already has the target 642/// attribute. 643static bool 644DeclHasAttr(const Decl *decl, const Attr *target) { 645 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 646 if (attr->getKind() == target->getKind()) 647 return true; 648 649 return false; 650} 651 652/// MergeAttributes - append attributes from the Old decl to the New one. 653static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 654 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 655 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 656 Attr *NewAttr = attr->clone(C); 657 NewAttr->setInherited(true); 658 New->addAttr(NewAttr); 659 } 660 } 661} 662 663/// Used in MergeFunctionDecl to keep track of function parameters in 664/// C. 665struct GNUCompatibleParamWarning { 666 ParmVarDecl *OldParm; 667 ParmVarDecl *NewParm; 668 QualType PromotedType; 669}; 670 671/// MergeFunctionDecl - We just parsed a function 'New' from 672/// declarator D which has the same name and scope as a previous 673/// declaration 'Old'. Figure out how to resolve this situation, 674/// merging decls or emitting diagnostics as appropriate. 675/// 676/// In C++, New and Old must be declarations that are not 677/// overloaded. Use IsOverload to determine whether New and Old are 678/// overloaded, and to select the Old declaration that New should be 679/// merged with. 680/// 681/// Returns true if there was an error, false otherwise. 682bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 683 assert(!isa<OverloadedFunctionDecl>(OldD) && 684 "Cannot merge with an overloaded function declaration"); 685 686 // Verify the old decl was also a function. 687 FunctionDecl *Old = 0; 688 if (FunctionTemplateDecl *OldFunctionTemplate 689 = dyn_cast<FunctionTemplateDecl>(OldD)) 690 Old = OldFunctionTemplate->getTemplatedDecl(); 691 else 692 Old = dyn_cast<FunctionDecl>(OldD); 693 if (!Old) { 694 Diag(New->getLocation(), diag::err_redefinition_different_kind) 695 << New->getDeclName(); 696 Diag(OldD->getLocation(), diag::note_previous_definition); 697 return true; 698 } 699 700 // Determine whether the previous declaration was a definition, 701 // implicit declaration, or a declaration. 702 diag::kind PrevDiag; 703 if (Old->isThisDeclarationADefinition()) 704 PrevDiag = diag::note_previous_definition; 705 else if (Old->isImplicit()) 706 PrevDiag = diag::note_previous_implicit_declaration; 707 else 708 PrevDiag = diag::note_previous_declaration; 709 710 QualType OldQType = Context.getCanonicalType(Old->getType()); 711 QualType NewQType = Context.getCanonicalType(New->getType()); 712 713 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 714 New->getStorageClass() == FunctionDecl::Static && 715 Old->getStorageClass() != FunctionDecl::Static) { 716 Diag(New->getLocation(), diag::err_static_non_static) 717 << New; 718 Diag(Old->getLocation(), PrevDiag); 719 return true; 720 } 721 722 if (getLangOptions().CPlusPlus) { 723 // (C++98 13.1p2): 724 // Certain function declarations cannot be overloaded: 725 // -- Function declarations that differ only in the return type 726 // cannot be overloaded. 727 QualType OldReturnType 728 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 729 QualType NewReturnType 730 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 731 if (OldReturnType != NewReturnType) { 732 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 733 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 734 return true; 735 } 736 737 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 738 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 739 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 740 NewMethod->getLexicalDeclContext()->isRecord()) { 741 // -- Member function declarations with the same name and the 742 // same parameter types cannot be overloaded if any of them 743 // is a static member function declaration. 744 if (OldMethod->isStatic() || NewMethod->isStatic()) { 745 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 746 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 747 return true; 748 } 749 750 // C++ [class.mem]p1: 751 // [...] A member shall not be declared twice in the 752 // member-specification, except that a nested class or member 753 // class template can be declared and then later defined. 754 unsigned NewDiag; 755 if (isa<CXXConstructorDecl>(OldMethod)) 756 NewDiag = diag::err_constructor_redeclared; 757 else if (isa<CXXDestructorDecl>(NewMethod)) 758 NewDiag = diag::err_destructor_redeclared; 759 else if (isa<CXXConversionDecl>(NewMethod)) 760 NewDiag = diag::err_conv_function_redeclared; 761 else 762 NewDiag = diag::err_member_redeclared; 763 764 Diag(New->getLocation(), NewDiag); 765 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 766 } 767 768 // (C++98 8.3.5p3): 769 // All declarations for a function shall agree exactly in both the 770 // return type and the parameter-type-list. 771 if (OldQType == NewQType) 772 return MergeCompatibleFunctionDecls(New, Old); 773 774 // Fall through for conflicting redeclarations and redefinitions. 775 } 776 777 // C: Function types need to be compatible, not identical. This handles 778 // duplicate function decls like "void f(int); void f(enum X);" properly. 779 if (!getLangOptions().CPlusPlus && 780 Context.typesAreCompatible(OldQType, NewQType)) { 781 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 782 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 783 const FunctionProtoType *OldProto = 0; 784 if (isa<FunctionNoProtoType>(NewFuncType) && 785 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 786 // The old declaration provided a function prototype, but the 787 // new declaration does not. Merge in the prototype. 788 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 789 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 790 OldProto->arg_type_end()); 791 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 792 ParamTypes.data(), ParamTypes.size(), 793 OldProto->isVariadic(), 794 OldProto->getTypeQuals()); 795 New->setType(NewQType); 796 New->setHasInheritedPrototype(); 797 798 // Synthesize a parameter for each argument type. 799 llvm::SmallVector<ParmVarDecl*, 16> Params; 800 for (FunctionProtoType::arg_type_iterator 801 ParamType = OldProto->arg_type_begin(), 802 ParamEnd = OldProto->arg_type_end(); 803 ParamType != ParamEnd; ++ParamType) { 804 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 805 SourceLocation(), 0, 806 *ParamType, /*DInfo=*/0, 807 VarDecl::None, 0); 808 Param->setImplicit(); 809 Params.push_back(Param); 810 } 811 812 New->setParams(Context, Params.data(), Params.size()); 813 } 814 815 return MergeCompatibleFunctionDecls(New, Old); 816 } 817 818 // GNU C permits a K&R definition to follow a prototype declaration 819 // if the declared types of the parameters in the K&R definition 820 // match the types in the prototype declaration, even when the 821 // promoted types of the parameters from the K&R definition differ 822 // from the types in the prototype. GCC then keeps the types from 823 // the prototype. 824 // 825 // If a variadic prototype is followed by a non-variadic K&R definition, 826 // the K&R definition becomes variadic. This is sort of an edge case, but 827 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 828 // C99 6.9.1p8. 829 if (!getLangOptions().CPlusPlus && 830 Old->hasPrototype() && !New->hasPrototype() && 831 New->getType()->getAsFunctionProtoType() && 832 Old->getNumParams() == New->getNumParams()) { 833 llvm::SmallVector<QualType, 16> ArgTypes; 834 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 835 const FunctionProtoType *OldProto 836 = Old->getType()->getAsFunctionProtoType(); 837 const FunctionProtoType *NewProto 838 = New->getType()->getAsFunctionProtoType(); 839 840 // Determine whether this is the GNU C extension. 841 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 842 NewProto->getResultType()); 843 bool LooseCompatible = !MergedReturn.isNull(); 844 for (unsigned Idx = 0, End = Old->getNumParams(); 845 LooseCompatible && Idx != End; ++Idx) { 846 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 847 ParmVarDecl *NewParm = New->getParamDecl(Idx); 848 if (Context.typesAreCompatible(OldParm->getType(), 849 NewProto->getArgType(Idx))) { 850 ArgTypes.push_back(NewParm->getType()); 851 } else if (Context.typesAreCompatible(OldParm->getType(), 852 NewParm->getType())) { 853 GNUCompatibleParamWarning Warn 854 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 855 Warnings.push_back(Warn); 856 ArgTypes.push_back(NewParm->getType()); 857 } else 858 LooseCompatible = false; 859 } 860 861 if (LooseCompatible) { 862 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 863 Diag(Warnings[Warn].NewParm->getLocation(), 864 diag::ext_param_promoted_not_compatible_with_prototype) 865 << Warnings[Warn].PromotedType 866 << Warnings[Warn].OldParm->getType(); 867 Diag(Warnings[Warn].OldParm->getLocation(), 868 diag::note_previous_declaration); 869 } 870 871 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 872 ArgTypes.size(), 873 OldProto->isVariadic(), 0)); 874 return MergeCompatibleFunctionDecls(New, Old); 875 } 876 877 // Fall through to diagnose conflicting types. 878 } 879 880 // A function that has already been declared has been redeclared or defined 881 // with a different type- show appropriate diagnostic 882 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 883 // The user has declared a builtin function with an incompatible 884 // signature. 885 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 886 // The function the user is redeclaring is a library-defined 887 // function like 'malloc' or 'printf'. Warn about the 888 // redeclaration, then pretend that we don't know about this 889 // library built-in. 890 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 891 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 892 << Old << Old->getType(); 893 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 894 Old->setInvalidDecl(); 895 return false; 896 } 897 898 PrevDiag = diag::note_previous_builtin_declaration; 899 } 900 901 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 902 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 903 return true; 904} 905 906/// \brief Completes the merge of two function declarations that are 907/// known to be compatible. 908/// 909/// This routine handles the merging of attributes and other 910/// properties of function declarations form the old declaration to 911/// the new declaration, once we know that New is in fact a 912/// redeclaration of Old. 913/// 914/// \returns false 915bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 916 // Merge the attributes 917 MergeAttributes(New, Old, Context); 918 919 // Merge the storage class. 920 if (Old->getStorageClass() != FunctionDecl::Extern) 921 New->setStorageClass(Old->getStorageClass()); 922 923 // Merge "inline" 924 if (Old->isInline()) 925 New->setInline(true); 926 927 // If this function declaration by itself qualifies as a C99 inline 928 // definition (C99 6.7.4p6), but the previous definition did not, 929 // then the function is not a C99 inline definition. 930 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 931 New->setC99InlineDefinition(false); 932 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 933 // Mark all preceding definitions as not being C99 inline definitions. 934 for (const FunctionDecl *Prev = Old; Prev; 935 Prev = Prev->getPreviousDeclaration()) 936 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 937 } 938 939 // Merge "pure" flag. 940 if (Old->isPure()) 941 New->setPure(); 942 943 // Merge the "deleted" flag. 944 if (Old->isDeleted()) 945 New->setDeleted(); 946 947 if (getLangOptions().CPlusPlus) 948 return MergeCXXFunctionDecl(New, Old); 949 950 return false; 951} 952 953/// MergeVarDecl - We just parsed a variable 'New' which has the same name 954/// and scope as a previous declaration 'Old'. Figure out how to resolve this 955/// situation, merging decls or emitting diagnostics as appropriate. 956/// 957/// Tentative definition rules (C99 6.9.2p2) are checked by 958/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 959/// definitions here, since the initializer hasn't been attached. 960/// 961void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 962 // If either decl is invalid, make sure the new one is marked invalid and 963 // don't do any other checking. 964 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 965 return New->setInvalidDecl(); 966 967 // Verify the old decl was also a variable. 968 VarDecl *Old = dyn_cast<VarDecl>(OldD); 969 if (!Old) { 970 Diag(New->getLocation(), diag::err_redefinition_different_kind) 971 << New->getDeclName(); 972 Diag(OldD->getLocation(), diag::note_previous_definition); 973 return New->setInvalidDecl(); 974 } 975 976 MergeAttributes(New, Old, Context); 977 978 // Merge the types 979 QualType MergedT; 980 if (getLangOptions().CPlusPlus) { 981 if (Context.hasSameType(New->getType(), Old->getType())) 982 MergedT = New->getType(); 983 // C++ [basic.types]p7: 984 // [...] The declared type of an array object might be an array of 985 // unknown size and therefore be incomplete at one point in a 986 // translation unit and complete later on; [...] 987 else if (Old->getType()->isIncompleteArrayType() && 988 New->getType()->isArrayType()) { 989 CanQual<ArrayType> OldArray 990 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 991 CanQual<ArrayType> NewArray 992 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 993 if (OldArray->getElementType() == NewArray->getElementType()) 994 MergedT = New->getType(); 995 } 996 } else { 997 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 998 } 999 if (MergedT.isNull()) { 1000 Diag(New->getLocation(), diag::err_redefinition_different_type) 1001 << New->getDeclName(); 1002 Diag(Old->getLocation(), diag::note_previous_definition); 1003 return New->setInvalidDecl(); 1004 } 1005 New->setType(MergedT); 1006 1007 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1008 if (New->getStorageClass() == VarDecl::Static && 1009 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1010 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1011 Diag(Old->getLocation(), diag::note_previous_definition); 1012 return New->setInvalidDecl(); 1013 } 1014 // C99 6.2.2p4: 1015 // For an identifier declared with the storage-class specifier 1016 // extern in a scope in which a prior declaration of that 1017 // identifier is visible,23) if the prior declaration specifies 1018 // internal or external linkage, the linkage of the identifier at 1019 // the later declaration is the same as the linkage specified at 1020 // the prior declaration. If no prior declaration is visible, or 1021 // if the prior declaration specifies no linkage, then the 1022 // identifier has external linkage. 1023 if (New->hasExternalStorage() && Old->hasLinkage()) 1024 /* Okay */; 1025 else if (New->getStorageClass() != VarDecl::Static && 1026 Old->getStorageClass() == VarDecl::Static) { 1027 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1028 Diag(Old->getLocation(), diag::note_previous_definition); 1029 return New->setInvalidDecl(); 1030 } 1031 1032 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1033 1034 // FIXME: The test for external storage here seems wrong? We still 1035 // need to check for mismatches. 1036 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1037 // Don't complain about out-of-line definitions of static members. 1038 !(Old->getLexicalDeclContext()->isRecord() && 1039 !New->getLexicalDeclContext()->isRecord())) { 1040 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1041 Diag(Old->getLocation(), diag::note_previous_definition); 1042 return New->setInvalidDecl(); 1043 } 1044 1045 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1046 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1047 Diag(Old->getLocation(), diag::note_previous_definition); 1048 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1049 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1050 Diag(Old->getLocation(), diag::note_previous_definition); 1051 } 1052 1053 // Keep a chain of previous declarations. 1054 New->setPreviousDeclaration(Old); 1055} 1056 1057/// CheckFallThrough - Check that we don't fall off the end of a 1058/// Statement that should return a value. 1059/// 1060/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1061/// MaybeFallThrough iff we might or might not fall off the end and 1062/// NeverFallThrough iff we never fall off the end of the statement. We assume 1063/// that functions not marked noreturn will return. 1064Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1065 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1066 1067 // FIXME: They should never return 0, fix that, delete this code. 1068 if (cfg == 0) 1069 return NeverFallThrough; 1070 // The CFG leaves in dead things, and we don't want to dead code paths to 1071 // confuse us, so we mark all live things first. 1072 std::queue<CFGBlock*> workq; 1073 llvm::BitVector live(cfg->getNumBlockIDs()); 1074 // Prep work queue 1075 workq.push(&cfg->getEntry()); 1076 // Solve 1077 while (!workq.empty()) { 1078 CFGBlock *item = workq.front(); 1079 workq.pop(); 1080 live.set(item->getBlockID()); 1081 for (CFGBlock::succ_iterator I=item->succ_begin(), 1082 E=item->succ_end(); 1083 I != E; 1084 ++I) { 1085 if ((*I) && !live[(*I)->getBlockID()]) { 1086 live.set((*I)->getBlockID()); 1087 workq.push(*I); 1088 } 1089 } 1090 } 1091 1092 // Now we know what is live, we check the live precessors of the exit block 1093 // and look for fall through paths, being careful to ignore normal returns, 1094 // and exceptional paths. 1095 bool HasLiveReturn = false; 1096 bool HasFakeEdge = false; 1097 bool HasPlainEdge = false; 1098 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1099 E = cfg->getExit().pred_end(); 1100 I != E; 1101 ++I) { 1102 CFGBlock& B = **I; 1103 if (!live[B.getBlockID()]) 1104 continue; 1105 if (B.size() == 0) { 1106 // A labeled empty statement, or the entry block... 1107 HasPlainEdge = true; 1108 continue; 1109 } 1110 Stmt *S = B[B.size()-1]; 1111 if (isa<ReturnStmt>(S)) { 1112 HasLiveReturn = true; 1113 continue; 1114 } 1115 if (isa<ObjCAtThrowStmt>(S)) { 1116 HasFakeEdge = true; 1117 continue; 1118 } 1119 if (isa<CXXThrowExpr>(S)) { 1120 HasFakeEdge = true; 1121 continue; 1122 } 1123 bool NoReturnEdge = false; 1124 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1125 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1126 if (CEE->getType().getNoReturnAttr()) { 1127 NoReturnEdge = true; 1128 HasFakeEdge = true; 1129 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1130 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1131 if (FD->hasAttr<NoReturnAttr>()) { 1132 NoReturnEdge = true; 1133 HasFakeEdge = true; 1134 } 1135 } 1136 } 1137 } 1138 // FIXME: Add noreturn message sends. 1139 if (NoReturnEdge == false) 1140 HasPlainEdge = true; 1141 } 1142 if (!HasPlainEdge) 1143 return NeverFallThrough; 1144 if (HasFakeEdge || HasLiveReturn) 1145 return MaybeFallThrough; 1146 // This says AlwaysFallThrough for calls to functions that are not marked 1147 // noreturn, that don't return. If people would like this warning to be more 1148 // accurate, such functions should be marked as noreturn. 1149 return AlwaysFallThrough; 1150} 1151 1152/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1153/// function that should return a value. Check that we don't fall off the end 1154/// of a noreturn function. We assume that functions and blocks not marked 1155/// noreturn will return. 1156void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1157 // FIXME: Would be nice if we had a better way to control cascading errors, 1158 // but for now, avoid them. The problem is that when Parse sees: 1159 // int foo() { return a; } 1160 // The return is eaten and the Sema code sees just: 1161 // int foo() { } 1162 // which this code would then warn about. 1163 if (getDiagnostics().hasErrorOccurred()) 1164 return; 1165 bool ReturnsVoid = false; 1166 bool HasNoReturn = false; 1167 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1168 if (FD->getResultType()->isVoidType()) 1169 ReturnsVoid = true; 1170 if (FD->hasAttr<NoReturnAttr>()) 1171 HasNoReturn = true; 1172 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1173 if (MD->getResultType()->isVoidType()) 1174 ReturnsVoid = true; 1175 if (MD->hasAttr<NoReturnAttr>()) 1176 HasNoReturn = true; 1177 } 1178 1179 // Short circuit for compilation speed. 1180 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1181 == Diagnostic::Ignored || ReturnsVoid) 1182 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1183 == Diagnostic::Ignored || !HasNoReturn) 1184 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1185 == Diagnostic::Ignored || !ReturnsVoid)) 1186 return; 1187 // FIXME: Funtion try block 1188 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1189 switch (CheckFallThrough(Body)) { 1190 case MaybeFallThrough: 1191 if (HasNoReturn) 1192 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1193 else if (!ReturnsVoid) 1194 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1195 break; 1196 case AlwaysFallThrough: 1197 if (HasNoReturn) 1198 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1199 else if (!ReturnsVoid) 1200 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1201 break; 1202 case NeverFallThrough: 1203 if (ReturnsVoid) 1204 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1205 break; 1206 } 1207 } 1208} 1209 1210/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1211/// that should return a value. Check that we don't fall off the end of a 1212/// noreturn block. We assume that functions and blocks not marked noreturn 1213/// will return. 1214void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1215 // FIXME: Would be nice if we had a better way to control cascading errors, 1216 // but for now, avoid them. The problem is that when Parse sees: 1217 // int foo() { return a; } 1218 // The return is eaten and the Sema code sees just: 1219 // int foo() { } 1220 // which this code would then warn about. 1221 if (getDiagnostics().hasErrorOccurred()) 1222 return; 1223 bool ReturnsVoid = false; 1224 bool HasNoReturn = false; 1225 if (const FunctionType *FT = BlockTy->getPointeeType()->getAsFunctionType()) { 1226 if (FT->getResultType()->isVoidType()) 1227 ReturnsVoid = true; 1228 if (FT->getNoReturnAttr()) 1229 HasNoReturn = true; 1230 } 1231 1232 // Short circuit for compilation speed. 1233 if (ReturnsVoid 1234 && !HasNoReturn 1235 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1236 == Diagnostic::Ignored || !ReturnsVoid)) 1237 return; 1238 // FIXME: Funtion try block 1239 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1240 switch (CheckFallThrough(Body)) { 1241 case MaybeFallThrough: 1242 if (HasNoReturn) 1243 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1244 else if (!ReturnsVoid) 1245 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1246 break; 1247 case AlwaysFallThrough: 1248 if (HasNoReturn) 1249 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1250 else if (!ReturnsVoid) 1251 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1252 break; 1253 case NeverFallThrough: 1254 if (ReturnsVoid) 1255 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1256 break; 1257 } 1258 } 1259} 1260 1261/// CheckParmsForFunctionDef - Check that the parameters of the given 1262/// function are appropriate for the definition of a function. This 1263/// takes care of any checks that cannot be performed on the 1264/// declaration itself, e.g., that the types of each of the function 1265/// parameters are complete. 1266bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1267 bool HasInvalidParm = false; 1268 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1269 ParmVarDecl *Param = FD->getParamDecl(p); 1270 1271 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1272 // function declarator that is part of a function definition of 1273 // that function shall not have incomplete type. 1274 // 1275 // This is also C++ [dcl.fct]p6. 1276 if (!Param->isInvalidDecl() && 1277 RequireCompleteType(Param->getLocation(), Param->getType(), 1278 diag::err_typecheck_decl_incomplete_type)) { 1279 Param->setInvalidDecl(); 1280 HasInvalidParm = true; 1281 } 1282 1283 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1284 // declaration of each parameter shall include an identifier. 1285 if (Param->getIdentifier() == 0 && 1286 !Param->isImplicit() && 1287 !getLangOptions().CPlusPlus) 1288 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1289 } 1290 1291 return HasInvalidParm; 1292} 1293 1294/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1295/// no declarator (e.g. "struct foo;") is parsed. 1296Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1297 // FIXME: Error on auto/register at file scope 1298 // FIXME: Error on inline/virtual/explicit 1299 // FIXME: Error on invalid restrict 1300 // FIXME: Warn on useless __thread 1301 // FIXME: Warn on useless const/volatile 1302 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1303 // FIXME: Warn on useless attributes 1304 TagDecl *Tag = 0; 1305 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1306 DS.getTypeSpecType() == DeclSpec::TST_struct || 1307 DS.getTypeSpecType() == DeclSpec::TST_union || 1308 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1309 if (!DS.getTypeRep()) // We probably had an error 1310 return DeclPtrTy(); 1311 1312 // Note that the above type specs guarantee that the 1313 // type rep is a Decl, whereas in many of the others 1314 // it's a Type. 1315 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1316 } 1317 1318 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1319 if (!Record->getDeclName() && Record->isDefinition() && 1320 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1321 if (getLangOptions().CPlusPlus || 1322 Record->getDeclContext()->isRecord()) 1323 return BuildAnonymousStructOrUnion(S, DS, Record); 1324 1325 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1326 << DS.getSourceRange(); 1327 } 1328 1329 // Microsoft allows unnamed struct/union fields. Don't complain 1330 // about them. 1331 // FIXME: Should we support Microsoft's extensions in this area? 1332 if (Record->getDeclName() && getLangOptions().Microsoft) 1333 return DeclPtrTy::make(Tag); 1334 } 1335 1336 if (!DS.isMissingDeclaratorOk() && 1337 DS.getTypeSpecType() != DeclSpec::TST_error) { 1338 // Warn about typedefs of enums without names, since this is an 1339 // extension in both Microsoft an GNU. 1340 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1341 Tag && isa<EnumDecl>(Tag)) { 1342 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1343 << DS.getSourceRange(); 1344 return DeclPtrTy::make(Tag); 1345 } 1346 1347 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1348 << DS.getSourceRange(); 1349 return DeclPtrTy(); 1350 } 1351 1352 return DeclPtrTy::make(Tag); 1353} 1354 1355/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1356/// anonymous struct or union AnonRecord into the owning context Owner 1357/// and scope S. This routine will be invoked just after we realize 1358/// that an unnamed union or struct is actually an anonymous union or 1359/// struct, e.g., 1360/// 1361/// @code 1362/// union { 1363/// int i; 1364/// float f; 1365/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1366/// // f into the surrounding scope.x 1367/// @endcode 1368/// 1369/// This routine is recursive, injecting the names of nested anonymous 1370/// structs/unions into the owning context and scope as well. 1371bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1372 RecordDecl *AnonRecord) { 1373 bool Invalid = false; 1374 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1375 FEnd = AnonRecord->field_end(); 1376 F != FEnd; ++F) { 1377 if ((*F)->getDeclName()) { 1378 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1379 LookupOrdinaryName, true); 1380 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1381 // C++ [class.union]p2: 1382 // The names of the members of an anonymous union shall be 1383 // distinct from the names of any other entity in the 1384 // scope in which the anonymous union is declared. 1385 unsigned diagKind 1386 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1387 : diag::err_anonymous_struct_member_redecl; 1388 Diag((*F)->getLocation(), diagKind) 1389 << (*F)->getDeclName(); 1390 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1391 Invalid = true; 1392 } else { 1393 // C++ [class.union]p2: 1394 // For the purpose of name lookup, after the anonymous union 1395 // definition, the members of the anonymous union are 1396 // considered to have been defined in the scope in which the 1397 // anonymous union is declared. 1398 Owner->makeDeclVisibleInContext(*F); 1399 S->AddDecl(DeclPtrTy::make(*F)); 1400 IdResolver.AddDecl(*F); 1401 } 1402 } else if (const RecordType *InnerRecordType 1403 = (*F)->getType()->getAs<RecordType>()) { 1404 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1405 if (InnerRecord->isAnonymousStructOrUnion()) 1406 Invalid = Invalid || 1407 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1408 } 1409 } 1410 1411 return Invalid; 1412} 1413 1414/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1415/// anonymous structure or union. Anonymous unions are a C++ feature 1416/// (C++ [class.union]) and a GNU C extension; anonymous structures 1417/// are a GNU C and GNU C++ extension. 1418Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1419 RecordDecl *Record) { 1420 DeclContext *Owner = Record->getDeclContext(); 1421 1422 // Diagnose whether this anonymous struct/union is an extension. 1423 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1424 Diag(Record->getLocation(), diag::ext_anonymous_union); 1425 else if (!Record->isUnion()) 1426 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1427 1428 // C and C++ require different kinds of checks for anonymous 1429 // structs/unions. 1430 bool Invalid = false; 1431 if (getLangOptions().CPlusPlus) { 1432 const char* PrevSpec = 0; 1433 unsigned DiagID; 1434 // C++ [class.union]p3: 1435 // Anonymous unions declared in a named namespace or in the 1436 // global namespace shall be declared static. 1437 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1438 (isa<TranslationUnitDecl>(Owner) || 1439 (isa<NamespaceDecl>(Owner) && 1440 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1441 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1442 Invalid = true; 1443 1444 // Recover by adding 'static'. 1445 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1446 PrevSpec, DiagID); 1447 } 1448 // C++ [class.union]p3: 1449 // A storage class is not allowed in a declaration of an 1450 // anonymous union in a class scope. 1451 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1452 isa<RecordDecl>(Owner)) { 1453 Diag(DS.getStorageClassSpecLoc(), 1454 diag::err_anonymous_union_with_storage_spec); 1455 Invalid = true; 1456 1457 // Recover by removing the storage specifier. 1458 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1459 PrevSpec, DiagID); 1460 } 1461 1462 // C++ [class.union]p2: 1463 // The member-specification of an anonymous union shall only 1464 // define non-static data members. [Note: nested types and 1465 // functions cannot be declared within an anonymous union. ] 1466 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1467 MemEnd = Record->decls_end(); 1468 Mem != MemEnd; ++Mem) { 1469 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1470 // C++ [class.union]p3: 1471 // An anonymous union shall not have private or protected 1472 // members (clause 11). 1473 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1474 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1475 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1476 Invalid = true; 1477 } 1478 } else if ((*Mem)->isImplicit()) { 1479 // Any implicit members are fine. 1480 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1481 // This is a type that showed up in an 1482 // elaborated-type-specifier inside the anonymous struct or 1483 // union, but which actually declares a type outside of the 1484 // anonymous struct or union. It's okay. 1485 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1486 if (!MemRecord->isAnonymousStructOrUnion() && 1487 MemRecord->getDeclName()) { 1488 // This is a nested type declaration. 1489 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1490 << (int)Record->isUnion(); 1491 Invalid = true; 1492 } 1493 } else { 1494 // We have something that isn't a non-static data 1495 // member. Complain about it. 1496 unsigned DK = diag::err_anonymous_record_bad_member; 1497 if (isa<TypeDecl>(*Mem)) 1498 DK = diag::err_anonymous_record_with_type; 1499 else if (isa<FunctionDecl>(*Mem)) 1500 DK = diag::err_anonymous_record_with_function; 1501 else if (isa<VarDecl>(*Mem)) 1502 DK = diag::err_anonymous_record_with_static; 1503 Diag((*Mem)->getLocation(), DK) 1504 << (int)Record->isUnion(); 1505 Invalid = true; 1506 } 1507 } 1508 } 1509 1510 if (!Record->isUnion() && !Owner->isRecord()) { 1511 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1512 << (int)getLangOptions().CPlusPlus; 1513 Invalid = true; 1514 } 1515 1516 // Create a declaration for this anonymous struct/union. 1517 NamedDecl *Anon = 0; 1518 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1519 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1520 /*IdentifierInfo=*/0, 1521 Context.getTypeDeclType(Record), 1522 // FIXME: Type source info. 1523 /*DInfo=*/0, 1524 /*BitWidth=*/0, /*Mutable=*/false); 1525 Anon->setAccess(AS_public); 1526 if (getLangOptions().CPlusPlus) 1527 FieldCollector->Add(cast<FieldDecl>(Anon)); 1528 } else { 1529 VarDecl::StorageClass SC; 1530 switch (DS.getStorageClassSpec()) { 1531 default: assert(0 && "Unknown storage class!"); 1532 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1533 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1534 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1535 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1536 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1537 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1538 case DeclSpec::SCS_mutable: 1539 // mutable can only appear on non-static class members, so it's always 1540 // an error here 1541 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1542 Invalid = true; 1543 SC = VarDecl::None; 1544 break; 1545 } 1546 1547 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1548 /*IdentifierInfo=*/0, 1549 Context.getTypeDeclType(Record), 1550 // FIXME: Type source info. 1551 /*DInfo=*/0, 1552 SC); 1553 } 1554 Anon->setImplicit(); 1555 1556 // Add the anonymous struct/union object to the current 1557 // context. We'll be referencing this object when we refer to one of 1558 // its members. 1559 Owner->addDecl(Anon); 1560 1561 // Inject the members of the anonymous struct/union into the owning 1562 // context and into the identifier resolver chain for name lookup 1563 // purposes. 1564 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1565 Invalid = true; 1566 1567 // Mark this as an anonymous struct/union type. Note that we do not 1568 // do this until after we have already checked and injected the 1569 // members of this anonymous struct/union type, because otherwise 1570 // the members could be injected twice: once by DeclContext when it 1571 // builds its lookup table, and once by 1572 // InjectAnonymousStructOrUnionMembers. 1573 Record->setAnonymousStructOrUnion(true); 1574 1575 if (Invalid) 1576 Anon->setInvalidDecl(); 1577 1578 return DeclPtrTy::make(Anon); 1579} 1580 1581 1582/// GetNameForDeclarator - Determine the full declaration name for the 1583/// given Declarator. 1584DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1585 switch (D.getKind()) { 1586 case Declarator::DK_Abstract: 1587 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1588 return DeclarationName(); 1589 1590 case Declarator::DK_Normal: 1591 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1592 return DeclarationName(D.getIdentifier()); 1593 1594 case Declarator::DK_Constructor: { 1595 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1596 return Context.DeclarationNames.getCXXConstructorName( 1597 Context.getCanonicalType(Ty)); 1598 } 1599 1600 case Declarator::DK_Destructor: { 1601 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1602 return Context.DeclarationNames.getCXXDestructorName( 1603 Context.getCanonicalType(Ty)); 1604 } 1605 1606 case Declarator::DK_Conversion: { 1607 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1608 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1609 return Context.DeclarationNames.getCXXConversionFunctionName( 1610 Context.getCanonicalType(Ty)); 1611 } 1612 1613 case Declarator::DK_Operator: 1614 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1615 return Context.DeclarationNames.getCXXOperatorName( 1616 D.getOverloadedOperator()); 1617 } 1618 1619 assert(false && "Unknown name kind"); 1620 return DeclarationName(); 1621} 1622 1623/// isNearlyMatchingFunction - Determine whether the C++ functions 1624/// Declaration and Definition are "nearly" matching. This heuristic 1625/// is used to improve diagnostics in the case where an out-of-line 1626/// function definition doesn't match any declaration within 1627/// the class or namespace. 1628static bool isNearlyMatchingFunction(ASTContext &Context, 1629 FunctionDecl *Declaration, 1630 FunctionDecl *Definition) { 1631 if (Declaration->param_size() != Definition->param_size()) 1632 return false; 1633 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1634 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1635 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1636 1637 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1638 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1639 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1640 return false; 1641 } 1642 1643 return true; 1644} 1645 1646Sema::DeclPtrTy 1647Sema::HandleDeclarator(Scope *S, Declarator &D, 1648 MultiTemplateParamsArg TemplateParamLists, 1649 bool IsFunctionDefinition) { 1650 DeclarationName Name = GetNameForDeclarator(D); 1651 1652 // All of these full declarators require an identifier. If it doesn't have 1653 // one, the ParsedFreeStandingDeclSpec action should be used. 1654 if (!Name) { 1655 if (!D.isInvalidType()) // Reject this if we think it is valid. 1656 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1657 diag::err_declarator_need_ident) 1658 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1659 return DeclPtrTy(); 1660 } 1661 1662 // The scope passed in may not be a decl scope. Zip up the scope tree until 1663 // we find one that is. 1664 while ((S->getFlags() & Scope::DeclScope) == 0 || 1665 (S->getFlags() & Scope::TemplateParamScope) != 0) 1666 S = S->getParent(); 1667 1668 // If this is an out-of-line definition of a member of a class template 1669 // or class template partial specialization, we may need to rebuild the 1670 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1671 // for more information. 1672 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1673 // handle expressions properly. 1674 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1675 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1676 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1677 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1678 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1679 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1680 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1681 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1682 // FIXME: Preserve type source info. 1683 QualType T = GetTypeFromParser(DS.getTypeRep()); 1684 EnterDeclaratorContext(S, DC); 1685 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1686 ExitDeclaratorContext(S); 1687 if (T.isNull()) 1688 return DeclPtrTy(); 1689 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1690 } 1691 } 1692 1693 DeclContext *DC; 1694 NamedDecl *PrevDecl; 1695 NamedDecl *New; 1696 1697 DeclaratorInfo *DInfo = 0; 1698 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1699 1700 // See if this is a redefinition of a variable in the same scope. 1701 if (D.getCXXScopeSpec().isInvalid()) { 1702 DC = CurContext; 1703 PrevDecl = 0; 1704 D.setInvalidType(); 1705 } else if (!D.getCXXScopeSpec().isSet()) { 1706 LookupNameKind NameKind = LookupOrdinaryName; 1707 1708 // If the declaration we're planning to build will be a function 1709 // or object with linkage, then look for another declaration with 1710 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1711 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1712 /* Do nothing*/; 1713 else if (R->isFunctionType()) { 1714 if (CurContext->isFunctionOrMethod() || 1715 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1716 NameKind = LookupRedeclarationWithLinkage; 1717 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1718 NameKind = LookupRedeclarationWithLinkage; 1719 else if (CurContext->getLookupContext()->isTranslationUnit() && 1720 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1721 NameKind = LookupRedeclarationWithLinkage; 1722 1723 DC = CurContext; 1724 PrevDecl = LookupName(S, Name, NameKind, true, 1725 NameKind == LookupRedeclarationWithLinkage, 1726 D.getIdentifierLoc()); 1727 } else { // Something like "int foo::x;" 1728 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1729 1730 if (!DC) { 1731 // If we could not compute the declaration context, it's because the 1732 // declaration context is dependent but does not refer to a class, 1733 // class template, or class template partial specialization. Complain 1734 // and return early, to avoid the coming semantic disaster. 1735 Diag(D.getIdentifierLoc(), 1736 diag::err_template_qualified_declarator_no_match) 1737 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1738 << D.getCXXScopeSpec().getRange(); 1739 return DeclPtrTy(); 1740 } 1741 1742 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1743 1744 // C++ 7.3.1.2p2: 1745 // Members (including explicit specializations of templates) of a named 1746 // namespace can also be defined outside that namespace by explicit 1747 // qualification of the name being defined, provided that the entity being 1748 // defined was already declared in the namespace and the definition appears 1749 // after the point of declaration in a namespace that encloses the 1750 // declarations namespace. 1751 // 1752 // Note that we only check the context at this point. We don't yet 1753 // have enough information to make sure that PrevDecl is actually 1754 // the declaration we want to match. For example, given: 1755 // 1756 // class X { 1757 // void f(); 1758 // void f(float); 1759 // }; 1760 // 1761 // void X::f(int) { } // ill-formed 1762 // 1763 // In this case, PrevDecl will point to the overload set 1764 // containing the two f's declared in X, but neither of them 1765 // matches. 1766 1767 // First check whether we named the global scope. 1768 if (isa<TranslationUnitDecl>(DC)) { 1769 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1770 << Name << D.getCXXScopeSpec().getRange(); 1771 } else if (!CurContext->Encloses(DC)) { 1772 // The qualifying scope doesn't enclose the original declaration. 1773 // Emit diagnostic based on current scope. 1774 SourceLocation L = D.getIdentifierLoc(); 1775 SourceRange R = D.getCXXScopeSpec().getRange(); 1776 if (isa<FunctionDecl>(CurContext)) 1777 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1778 else 1779 Diag(L, diag::err_invalid_declarator_scope) 1780 << Name << cast<NamedDecl>(DC) << R; 1781 D.setInvalidType(); 1782 } 1783 } 1784 1785 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1786 // Maybe we will complain about the shadowed template parameter. 1787 if (!D.isInvalidType()) 1788 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1789 D.setInvalidType(); 1790 1791 // Just pretend that we didn't see the previous declaration. 1792 PrevDecl = 0; 1793 } 1794 1795 // In C++, the previous declaration we find might be a tag type 1796 // (class or enum). In this case, the new declaration will hide the 1797 // tag type. Note that this does does not apply if we're declaring a 1798 // typedef (C++ [dcl.typedef]p4). 1799 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1800 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1801 PrevDecl = 0; 1802 1803 bool Redeclaration = false; 1804 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1805 if (TemplateParamLists.size()) { 1806 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1807 return DeclPtrTy(); 1808 } 1809 1810 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1811 } else if (R->isFunctionType()) { 1812 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1813 move(TemplateParamLists), 1814 IsFunctionDefinition, Redeclaration); 1815 } else { 1816 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1817 move(TemplateParamLists), 1818 Redeclaration); 1819 } 1820 1821 if (New == 0) 1822 return DeclPtrTy(); 1823 1824 // If this has an identifier and is not an invalid redeclaration, 1825 // add it to the scope stack. 1826 if (Name && !(Redeclaration && New->isInvalidDecl())) 1827 PushOnScopeChains(New, S); 1828 1829 return DeclPtrTy::make(New); 1830} 1831 1832/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1833/// types into constant array types in certain situations which would otherwise 1834/// be errors (for GCC compatibility). 1835static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1836 ASTContext &Context, 1837 bool &SizeIsNegative) { 1838 // This method tries to turn a variable array into a constant 1839 // array even when the size isn't an ICE. This is necessary 1840 // for compatibility with code that depends on gcc's buggy 1841 // constant expression folding, like struct {char x[(int)(char*)2];} 1842 SizeIsNegative = false; 1843 1844 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1845 QualType Pointee = PTy->getPointeeType(); 1846 QualType FixedType = 1847 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1848 if (FixedType.isNull()) return FixedType; 1849 FixedType = Context.getPointerType(FixedType); 1850 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1851 return FixedType; 1852 } 1853 1854 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1855 if (!VLATy) 1856 return QualType(); 1857 // FIXME: We should probably handle this case 1858 if (VLATy->getElementType()->isVariablyModifiedType()) 1859 return QualType(); 1860 1861 Expr::EvalResult EvalResult; 1862 if (!VLATy->getSizeExpr() || 1863 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1864 !EvalResult.Val.isInt()) 1865 return QualType(); 1866 1867 llvm::APSInt &Res = EvalResult.Val.getInt(); 1868 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1869 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1870 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1871 // so as to transfer ownership to the ConstantArrayWithExpr. 1872 // Alternatively, we could "clone" it (how?). 1873 // Since we don't know how to do things above, we just use the 1874 // very same Expr*. 1875 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1876 Res, ArySizeExpr, 1877 ArrayType::Normal, 0, 1878 VLATy->getBracketsRange()); 1879 } 1880 1881 SizeIsNegative = true; 1882 return QualType(); 1883} 1884 1885/// \brief Register the given locally-scoped external C declaration so 1886/// that it can be found later for redeclarations 1887void 1888Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1889 Scope *S) { 1890 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1891 "Decl is not a locally-scoped decl!"); 1892 // Note that we have a locally-scoped external with this name. 1893 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1894 1895 if (!PrevDecl) 1896 return; 1897 1898 // If there was a previous declaration of this variable, it may be 1899 // in our identifier chain. Update the identifier chain with the new 1900 // declaration. 1901 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1902 // The previous declaration was found on the identifer resolver 1903 // chain, so remove it from its scope. 1904 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1905 S = S->getParent(); 1906 1907 if (S) 1908 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1909 } 1910} 1911 1912/// \brief Diagnose function specifiers on a declaration of an identifier that 1913/// does not identify a function. 1914void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1915 // FIXME: We should probably indicate the identifier in question to avoid 1916 // confusion for constructs like "inline int a(), b;" 1917 if (D.getDeclSpec().isInlineSpecified()) 1918 Diag(D.getDeclSpec().getInlineSpecLoc(), 1919 diag::err_inline_non_function); 1920 1921 if (D.getDeclSpec().isVirtualSpecified()) 1922 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1923 diag::err_virtual_non_function); 1924 1925 if (D.getDeclSpec().isExplicitSpecified()) 1926 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1927 diag::err_explicit_non_function); 1928} 1929 1930NamedDecl* 1931Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1932 QualType R, DeclaratorInfo *DInfo, 1933 Decl* PrevDecl, bool &Redeclaration) { 1934 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1935 if (D.getCXXScopeSpec().isSet()) { 1936 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1937 << D.getCXXScopeSpec().getRange(); 1938 D.setInvalidType(); 1939 // Pretend we didn't see the scope specifier. 1940 DC = 0; 1941 } 1942 1943 if (getLangOptions().CPlusPlus) { 1944 // Check that there are no default arguments (C++ only). 1945 CheckExtraCXXDefaultArguments(D); 1946 } 1947 1948 DiagnoseFunctionSpecifiers(D); 1949 1950 if (D.getDeclSpec().isThreadSpecified()) 1951 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1952 1953 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1954 if (!NewTD) return 0; 1955 1956 if (D.isInvalidType()) 1957 NewTD->setInvalidDecl(); 1958 1959 // Handle attributes prior to checking for duplicates in MergeVarDecl 1960 ProcessDeclAttributes(S, NewTD, D); 1961 // Merge the decl with the existing one if appropriate. If the decl is 1962 // in an outer scope, it isn't the same thing. 1963 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1964 Redeclaration = true; 1965 MergeTypeDefDecl(NewTD, PrevDecl); 1966 } 1967 1968 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1969 // then it shall have block scope. 1970 QualType T = NewTD->getUnderlyingType(); 1971 if (T->isVariablyModifiedType()) { 1972 CurFunctionNeedsScopeChecking = true; 1973 1974 if (S->getFnParent() == 0) { 1975 bool SizeIsNegative; 1976 QualType FixedTy = 1977 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1978 if (!FixedTy.isNull()) { 1979 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1980 NewTD->setUnderlyingType(FixedTy); 1981 } else { 1982 if (SizeIsNegative) 1983 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1984 else if (T->isVariableArrayType()) 1985 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1986 else 1987 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1988 NewTD->setInvalidDecl(); 1989 } 1990 } 1991 } 1992 1993 // If this is the C FILE type, notify the AST context. 1994 if (IdentifierInfo *II = NewTD->getIdentifier()) 1995 if (!NewTD->isInvalidDecl() && 1996 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1997 if (II->isStr("FILE")) 1998 Context.setFILEDecl(NewTD); 1999 else if (II->isStr("jmp_buf")) 2000 Context.setjmp_bufDecl(NewTD); 2001 else if (II->isStr("sigjmp_buf")) 2002 Context.setsigjmp_bufDecl(NewTD); 2003 } 2004 2005 return NewTD; 2006} 2007 2008/// \brief Determines whether the given declaration is an out-of-scope 2009/// previous declaration. 2010/// 2011/// This routine should be invoked when name lookup has found a 2012/// previous declaration (PrevDecl) that is not in the scope where a 2013/// new declaration by the same name is being introduced. If the new 2014/// declaration occurs in a local scope, previous declarations with 2015/// linkage may still be considered previous declarations (C99 2016/// 6.2.2p4-5, C++ [basic.link]p6). 2017/// 2018/// \param PrevDecl the previous declaration found by name 2019/// lookup 2020/// 2021/// \param DC the context in which the new declaration is being 2022/// declared. 2023/// 2024/// \returns true if PrevDecl is an out-of-scope previous declaration 2025/// for a new delcaration with the same name. 2026static bool 2027isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2028 ASTContext &Context) { 2029 if (!PrevDecl) 2030 return 0; 2031 2032 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2033 // case we need to check each of the overloaded functions. 2034 if (!PrevDecl->hasLinkage()) 2035 return false; 2036 2037 if (Context.getLangOptions().CPlusPlus) { 2038 // C++ [basic.link]p6: 2039 // If there is a visible declaration of an entity with linkage 2040 // having the same name and type, ignoring entities declared 2041 // outside the innermost enclosing namespace scope, the block 2042 // scope declaration declares that same entity and receives the 2043 // linkage of the previous declaration. 2044 DeclContext *OuterContext = DC->getLookupContext(); 2045 if (!OuterContext->isFunctionOrMethod()) 2046 // This rule only applies to block-scope declarations. 2047 return false; 2048 else { 2049 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2050 if (PrevOuterContext->isRecord()) 2051 // We found a member function: ignore it. 2052 return false; 2053 else { 2054 // Find the innermost enclosing namespace for the new and 2055 // previous declarations. 2056 while (!OuterContext->isFileContext()) 2057 OuterContext = OuterContext->getParent(); 2058 while (!PrevOuterContext->isFileContext()) 2059 PrevOuterContext = PrevOuterContext->getParent(); 2060 2061 // The previous declaration is in a different namespace, so it 2062 // isn't the same function. 2063 if (OuterContext->getPrimaryContext() != 2064 PrevOuterContext->getPrimaryContext()) 2065 return false; 2066 } 2067 } 2068 } 2069 2070 return true; 2071} 2072 2073NamedDecl* 2074Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2075 QualType R, DeclaratorInfo *DInfo, 2076 NamedDecl* PrevDecl, 2077 MultiTemplateParamsArg TemplateParamLists, 2078 bool &Redeclaration) { 2079 DeclarationName Name = GetNameForDeclarator(D); 2080 2081 // Check that there are no default arguments (C++ only). 2082 if (getLangOptions().CPlusPlus) 2083 CheckExtraCXXDefaultArguments(D); 2084 2085 VarDecl *NewVD; 2086 VarDecl::StorageClass SC; 2087 switch (D.getDeclSpec().getStorageClassSpec()) { 2088 default: assert(0 && "Unknown storage class!"); 2089 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2090 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2091 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2092 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2093 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2094 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2095 case DeclSpec::SCS_mutable: 2096 // mutable can only appear on non-static class members, so it's always 2097 // an error here 2098 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2099 D.setInvalidType(); 2100 SC = VarDecl::None; 2101 break; 2102 } 2103 2104 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2105 if (!II) { 2106 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2107 << Name.getAsString(); 2108 return 0; 2109 } 2110 2111 DiagnoseFunctionSpecifiers(D); 2112 2113 if (!DC->isRecord() && S->getFnParent() == 0) { 2114 // C99 6.9p2: The storage-class specifiers auto and register shall not 2115 // appear in the declaration specifiers in an external declaration. 2116 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2117 2118 // If this is a register variable with an asm label specified, then this 2119 // is a GNU extension. 2120 if (SC == VarDecl::Register && D.getAsmLabel()) 2121 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2122 else 2123 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2124 D.setInvalidType(); 2125 } 2126 } 2127 if (DC->isRecord() && !CurContext->isRecord()) { 2128 // This is an out-of-line definition of a static data member. 2129 if (SC == VarDecl::Static) { 2130 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2131 diag::err_static_out_of_line) 2132 << CodeModificationHint::CreateRemoval( 2133 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2134 } else if (SC == VarDecl::None) 2135 SC = VarDecl::Static; 2136 } 2137 if (SC == VarDecl::Static) { 2138 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2139 if (RD->isLocalClass()) 2140 Diag(D.getIdentifierLoc(), 2141 diag::err_static_data_member_not_allowed_in_local_class) 2142 << Name << RD->getDeclName(); 2143 } 2144 } 2145 2146 // Match up the template parameter lists with the scope specifier, then 2147 // determine whether we have a template or a template specialization. 2148 if (TemplateParameterList *TemplateParams 2149 = MatchTemplateParametersToScopeSpecifier( 2150 D.getDeclSpec().getSourceRange().getBegin(), 2151 D.getCXXScopeSpec(), 2152 (TemplateParameterList**)TemplateParamLists.get(), 2153 TemplateParamLists.size())) { 2154 if (TemplateParams->size() > 0) { 2155 // There is no such thing as a variable template. 2156 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2157 << II 2158 << SourceRange(TemplateParams->getTemplateLoc(), 2159 TemplateParams->getRAngleLoc()); 2160 return 0; 2161 } else { 2162 // There is an extraneous 'template<>' for this variable. Complain 2163 // about it, but allow the declaration of the variable. 2164 Diag(TemplateParams->getTemplateLoc(), 2165 diag::err_template_variable_noparams) 2166 << II 2167 << SourceRange(TemplateParams->getTemplateLoc(), 2168 TemplateParams->getRAngleLoc()); 2169 } 2170 } 2171 2172 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2173 II, R, DInfo, SC); 2174 2175 if (D.isInvalidType()) 2176 NewVD->setInvalidDecl(); 2177 2178 if (D.getDeclSpec().isThreadSpecified()) { 2179 if (NewVD->hasLocalStorage()) 2180 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2181 else if (!Context.Target.isTLSSupported()) 2182 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2183 else 2184 NewVD->setThreadSpecified(true); 2185 } 2186 2187 // Set the lexical context. If the declarator has a C++ scope specifier, the 2188 // lexical context will be different from the semantic context. 2189 NewVD->setLexicalDeclContext(CurContext); 2190 2191 // Handle attributes prior to checking for duplicates in MergeVarDecl 2192 ProcessDeclAttributes(S, NewVD, D); 2193 2194 // Handle GNU asm-label extension (encoded as an attribute). 2195 if (Expr *E = (Expr*) D.getAsmLabel()) { 2196 // The parser guarantees this is a string. 2197 StringLiteral *SE = cast<StringLiteral>(E); 2198 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2199 SE->getByteLength()))); 2200 } 2201 2202 // If name lookup finds a previous declaration that is not in the 2203 // same scope as the new declaration, this may still be an 2204 // acceptable redeclaration. 2205 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2206 !(NewVD->hasLinkage() && 2207 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2208 PrevDecl = 0; 2209 2210 // Merge the decl with the existing one if appropriate. 2211 if (PrevDecl) { 2212 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2213 // The user tried to define a non-static data member 2214 // out-of-line (C++ [dcl.meaning]p1). 2215 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2216 << D.getCXXScopeSpec().getRange(); 2217 PrevDecl = 0; 2218 NewVD->setInvalidDecl(); 2219 } 2220 } else if (D.getCXXScopeSpec().isSet()) { 2221 // No previous declaration in the qualifying scope. 2222 NestedNameSpecifier *NNS = 2223 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2224 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2225 D.getCXXScopeSpec().getRange()); 2226 NewVD->setInvalidDecl(); 2227 } 2228 2229 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2230 2231 // attributes declared post-definition are currently ignored 2232 if (PrevDecl) { 2233 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2234 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2235 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2236 Diag(Def->getLocation(), diag::note_previous_definition); 2237 } 2238 } 2239 2240 // If this is a locally-scoped extern C variable, update the map of 2241 // such variables. 2242 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 2243 !NewVD->isInvalidDecl()) 2244 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2245 2246 return NewVD; 2247} 2248 2249/// \brief Perform semantic checking on a newly-created variable 2250/// declaration. 2251/// 2252/// This routine performs all of the type-checking required for a 2253/// variable declaration once it has been built. It is used both to 2254/// check variables after they have been parsed and their declarators 2255/// have been translated into a declaration, and to check variables 2256/// that have been instantiated from a template. 2257/// 2258/// Sets NewVD->isInvalidDecl() if an error was encountered. 2259void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2260 bool &Redeclaration) { 2261 // If the decl is already known invalid, don't check it. 2262 if (NewVD->isInvalidDecl()) 2263 return; 2264 2265 QualType T = NewVD->getType(); 2266 2267 if (T->isObjCInterfaceType()) { 2268 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2269 return NewVD->setInvalidDecl(); 2270 } 2271 2272 // The variable can not have an abstract class type. 2273 if (RequireNonAbstractType(NewVD->getLocation(), T, 2274 diag::err_abstract_type_in_decl, 2275 AbstractVariableType)) 2276 return NewVD->setInvalidDecl(); 2277 2278 // Emit an error if an address space was applied to decl with local storage. 2279 // This includes arrays of objects with address space qualifiers, but not 2280 // automatic variables that point to other address spaces. 2281 // ISO/IEC TR 18037 S5.1.2 2282 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2283 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2284 return NewVD->setInvalidDecl(); 2285 } 2286 2287 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2288 && !NewVD->hasAttr<BlocksAttr>()) 2289 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2290 2291 bool isVM = T->isVariablyModifiedType(); 2292 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2293 NewVD->hasAttr<BlocksAttr>()) 2294 CurFunctionNeedsScopeChecking = true; 2295 2296 if ((isVM && NewVD->hasLinkage()) || 2297 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2298 bool SizeIsNegative; 2299 QualType FixedTy = 2300 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2301 2302 if (FixedTy.isNull() && T->isVariableArrayType()) { 2303 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2304 // FIXME: This won't give the correct result for 2305 // int a[10][n]; 2306 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2307 2308 if (NewVD->isFileVarDecl()) 2309 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2310 << SizeRange; 2311 else if (NewVD->getStorageClass() == VarDecl::Static) 2312 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2313 << SizeRange; 2314 else 2315 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2316 << SizeRange; 2317 return NewVD->setInvalidDecl(); 2318 } 2319 2320 if (FixedTy.isNull()) { 2321 if (NewVD->isFileVarDecl()) 2322 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2323 else 2324 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2325 return NewVD->setInvalidDecl(); 2326 } 2327 2328 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2329 NewVD->setType(FixedTy); 2330 } 2331 2332 if (!PrevDecl && NewVD->isExternC(Context)) { 2333 // Since we did not find anything by this name and we're declaring 2334 // an extern "C" variable, look for a non-visible extern "C" 2335 // declaration with the same name. 2336 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2337 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2338 if (Pos != LocallyScopedExternalDecls.end()) 2339 PrevDecl = Pos->second; 2340 } 2341 2342 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2343 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2344 << T; 2345 return NewVD->setInvalidDecl(); 2346 } 2347 2348 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2349 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2350 return NewVD->setInvalidDecl(); 2351 } 2352 2353 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2354 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2355 return NewVD->setInvalidDecl(); 2356 } 2357 2358 if (PrevDecl) { 2359 Redeclaration = true; 2360 MergeVarDecl(NewVD, PrevDecl); 2361 } 2362} 2363 2364static bool isUsingDecl(Decl *D) { 2365 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2366} 2367 2368NamedDecl* 2369Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2370 QualType R, DeclaratorInfo *DInfo, 2371 NamedDecl* PrevDecl, 2372 MultiTemplateParamsArg TemplateParamLists, 2373 bool IsFunctionDefinition, bool &Redeclaration) { 2374 assert(R.getTypePtr()->isFunctionType()); 2375 2376 DeclarationName Name = GetNameForDeclarator(D); 2377 FunctionDecl::StorageClass SC = FunctionDecl::None; 2378 switch (D.getDeclSpec().getStorageClassSpec()) { 2379 default: assert(0 && "Unknown storage class!"); 2380 case DeclSpec::SCS_auto: 2381 case DeclSpec::SCS_register: 2382 case DeclSpec::SCS_mutable: 2383 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2384 diag::err_typecheck_sclass_func); 2385 D.setInvalidType(); 2386 break; 2387 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2388 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2389 case DeclSpec::SCS_static: { 2390 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2391 // C99 6.7.1p5: 2392 // The declaration of an identifier for a function that has 2393 // block scope shall have no explicit storage-class specifier 2394 // other than extern 2395 // See also (C++ [dcl.stc]p4). 2396 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2397 diag::err_static_block_func); 2398 SC = FunctionDecl::None; 2399 } else 2400 SC = FunctionDecl::Static; 2401 break; 2402 } 2403 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2404 } 2405 2406 if (D.getDeclSpec().isThreadSpecified()) 2407 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2408 2409 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2410 bool isInline = D.getDeclSpec().isInlineSpecified(); 2411 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2412 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2413 2414 // Check that the return type is not an abstract class type. 2415 // For record types, this is done by the AbstractClassUsageDiagnoser once 2416 // the class has been completely parsed. 2417 if (!DC->isRecord() && 2418 RequireNonAbstractType(D.getIdentifierLoc(), 2419 R->getAsFunctionType()->getResultType(), 2420 diag::err_abstract_type_in_decl, 2421 AbstractReturnType)) 2422 D.setInvalidType(); 2423 2424 // Do not allow returning a objc interface by-value. 2425 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2426 Diag(D.getIdentifierLoc(), 2427 diag::err_object_cannot_be_passed_returned_by_value) << 0 2428 << R->getAsFunctionType()->getResultType(); 2429 D.setInvalidType(); 2430 } 2431 2432 bool isVirtualOkay = false; 2433 FunctionDecl *NewFD; 2434 2435 if (isFriend) { 2436 // DC is the namespace in which the function is being declared. 2437 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2438 "friend function being created in a non-namespace context"); 2439 2440 // C++ [class.friend]p5 2441 // A function can be defined in a friend declaration of a 2442 // class . . . . Such a function is implicitly inline. 2443 isInline |= IsFunctionDefinition; 2444 } 2445 2446 if (D.getKind() == Declarator::DK_Constructor) { 2447 // This is a C++ constructor declaration. 2448 assert(DC->isRecord() && 2449 "Constructors can only be declared in a member context"); 2450 2451 R = CheckConstructorDeclarator(D, R, SC); 2452 2453 // Create the new declaration 2454 NewFD = CXXConstructorDecl::Create(Context, 2455 cast<CXXRecordDecl>(DC), 2456 D.getIdentifierLoc(), Name, R, DInfo, 2457 isExplicit, isInline, 2458 /*isImplicitlyDeclared=*/false); 2459 } else if (D.getKind() == Declarator::DK_Destructor) { 2460 // This is a C++ destructor declaration. 2461 if (DC->isRecord()) { 2462 R = CheckDestructorDeclarator(D, SC); 2463 2464 NewFD = CXXDestructorDecl::Create(Context, 2465 cast<CXXRecordDecl>(DC), 2466 D.getIdentifierLoc(), Name, R, 2467 isInline, 2468 /*isImplicitlyDeclared=*/false); 2469 2470 isVirtualOkay = true; 2471 } else { 2472 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2473 2474 // Create a FunctionDecl to satisfy the function definition parsing 2475 // code path. 2476 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2477 Name, R, DInfo, SC, isInline, 2478 /*hasPrototype=*/true); 2479 D.setInvalidType(); 2480 } 2481 } else if (D.getKind() == Declarator::DK_Conversion) { 2482 if (!DC->isRecord()) { 2483 Diag(D.getIdentifierLoc(), 2484 diag::err_conv_function_not_member); 2485 return 0; 2486 } 2487 2488 CheckConversionDeclarator(D, R, SC); 2489 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2490 D.getIdentifierLoc(), Name, R, DInfo, 2491 isInline, isExplicit); 2492 2493 isVirtualOkay = true; 2494 } else if (DC->isRecord()) { 2495 // If the of the function is the same as the name of the record, then this 2496 // must be an invalid constructor that has a return type. 2497 // (The parser checks for a return type and makes the declarator a 2498 // constructor if it has no return type). 2499 // must have an invalid constructor that has a return type 2500 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2501 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2502 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2503 << SourceRange(D.getIdentifierLoc()); 2504 return 0; 2505 } 2506 2507 // This is a C++ method declaration. 2508 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2509 D.getIdentifierLoc(), Name, R, DInfo, 2510 (SC == FunctionDecl::Static), isInline); 2511 2512 isVirtualOkay = (SC != FunctionDecl::Static); 2513 } else { 2514 // Determine whether the function was written with a 2515 // prototype. This true when: 2516 // - we're in C++ (where every function has a prototype), 2517 // - there is a prototype in the declarator, or 2518 // - the type R of the function is some kind of typedef or other reference 2519 // to a type name (which eventually refers to a function type). 2520 bool HasPrototype = 2521 getLangOptions().CPlusPlus || 2522 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2523 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2524 2525 NewFD = FunctionDecl::Create(Context, DC, 2526 D.getIdentifierLoc(), 2527 Name, R, DInfo, SC, isInline, HasPrototype); 2528 } 2529 2530 if (D.isInvalidType()) 2531 NewFD->setInvalidDecl(); 2532 2533 // Set the lexical context. If the declarator has a C++ 2534 // scope specifier, or is the object of a friend declaration, the 2535 // lexical context will be different from the semantic context. 2536 NewFD->setLexicalDeclContext(CurContext); 2537 2538 if (isFriend) 2539 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2540 2541 // Match up the template parameter lists with the scope specifier, then 2542 // determine whether we have a template or a template specialization. 2543 FunctionTemplateDecl *FunctionTemplate = 0; 2544 if (TemplateParameterList *TemplateParams 2545 = MatchTemplateParametersToScopeSpecifier( 2546 D.getDeclSpec().getSourceRange().getBegin(), 2547 D.getCXXScopeSpec(), 2548 (TemplateParameterList**)TemplateParamLists.get(), 2549 TemplateParamLists.size())) { 2550 if (TemplateParams->size() > 0) { 2551 // This is a function template 2552 2553 // Check that we can declare a template here. 2554 if (CheckTemplateDeclScope(S, TemplateParams)) 2555 return 0; 2556 2557 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2558 NewFD->getLocation(), 2559 Name, TemplateParams, 2560 NewFD); 2561 FunctionTemplate->setLexicalDeclContext(CurContext); 2562 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2563 } else { 2564 // FIXME: Handle function template specializations 2565 } 2566 2567 // FIXME: Free this memory properly. 2568 TemplateParamLists.release(); 2569 } 2570 2571 // C++ [dcl.fct.spec]p5: 2572 // The virtual specifier shall only be used in declarations of 2573 // nonstatic class member functions that appear within a 2574 // member-specification of a class declaration; see 10.3. 2575 // 2576 if (isVirtual && !NewFD->isInvalidDecl()) { 2577 if (!isVirtualOkay) { 2578 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2579 diag::err_virtual_non_function); 2580 } else if (!CurContext->isRecord()) { 2581 // 'virtual' was specified outside of the class. 2582 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2583 << CodeModificationHint::CreateRemoval( 2584 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2585 } else { 2586 // Okay: Add virtual to the method. 2587 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2588 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2589 CurClass->setAggregate(false); 2590 CurClass->setPOD(false); 2591 CurClass->setEmpty(false); 2592 CurClass->setPolymorphic(true); 2593 CurClass->setHasTrivialConstructor(false); 2594 CurClass->setHasTrivialCopyConstructor(false); 2595 CurClass->setHasTrivialCopyAssignment(false); 2596 } 2597 } 2598 2599 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2600 // Look for virtual methods in base classes that this method might override. 2601 2602 BasePaths Paths; 2603 if (LookupInBases(cast<CXXRecordDecl>(DC), 2604 MemberLookupCriteria(NewMD), Paths)) { 2605 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2606 E = Paths.found_decls_end(); I != E; ++I) { 2607 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2608 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2609 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2610 NewMD->addOverriddenMethod(OldMD); 2611 } 2612 } 2613 } 2614 } 2615 2616 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2617 !CurContext->isRecord()) { 2618 // C++ [class.static]p1: 2619 // A data or function member of a class may be declared static 2620 // in a class definition, in which case it is a static member of 2621 // the class. 2622 2623 // Complain about the 'static' specifier if it's on an out-of-line 2624 // member function definition. 2625 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2626 diag::err_static_out_of_line) 2627 << CodeModificationHint::CreateRemoval( 2628 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2629 } 2630 2631 // Handle GNU asm-label extension (encoded as an attribute). 2632 if (Expr *E = (Expr*) D.getAsmLabel()) { 2633 // The parser guarantees this is a string. 2634 StringLiteral *SE = cast<StringLiteral>(E); 2635 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2636 SE->getByteLength()))); 2637 } 2638 2639 // Copy the parameter declarations from the declarator D to the function 2640 // declaration NewFD, if they are available. First scavenge them into Params. 2641 llvm::SmallVector<ParmVarDecl*, 16> Params; 2642 if (D.getNumTypeObjects() > 0) { 2643 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2644 2645 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2646 // function that takes no arguments, not a function that takes a 2647 // single void argument. 2648 // We let through "const void" here because Sema::GetTypeForDeclarator 2649 // already checks for that case. 2650 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2651 FTI.ArgInfo[0].Param && 2652 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2653 // Empty arg list, don't push any params. 2654 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2655 2656 // In C++, the empty parameter-type-list must be spelled "void"; a 2657 // typedef of void is not permitted. 2658 if (getLangOptions().CPlusPlus && 2659 Param->getType().getUnqualifiedType() != Context.VoidTy) 2660 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2661 // FIXME: Leaks decl? 2662 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2663 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2664 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2665 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2666 Param->setDeclContext(NewFD); 2667 Params.push_back(Param); 2668 } 2669 } 2670 2671 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2672 // When we're declaring a function with a typedef, typeof, etc as in the 2673 // following example, we'll need to synthesize (unnamed) 2674 // parameters for use in the declaration. 2675 // 2676 // @code 2677 // typedef void fn(int); 2678 // fn f; 2679 // @endcode 2680 2681 // Synthesize a parameter for each argument type. 2682 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2683 AE = FT->arg_type_end(); AI != AE; ++AI) { 2684 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2685 SourceLocation(), 0, 2686 *AI, /*DInfo=*/0, 2687 VarDecl::None, 0); 2688 Param->setImplicit(); 2689 Params.push_back(Param); 2690 } 2691 } else { 2692 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2693 "Should not need args for typedef of non-prototype fn"); 2694 } 2695 // Finally, we know we have the right number of parameters, install them. 2696 NewFD->setParams(Context, Params.data(), Params.size()); 2697 2698 // If name lookup finds a previous declaration that is not in the 2699 // same scope as the new declaration, this may still be an 2700 // acceptable redeclaration. 2701 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2702 !(NewFD->hasLinkage() && 2703 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2704 PrevDecl = 0; 2705 2706 // Perform semantic checking on the function declaration. 2707 bool OverloadableAttrRequired = false; // FIXME: HACK! 2708 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2709 /*FIXME:*/OverloadableAttrRequired); 2710 2711 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2712 // An out-of-line member function declaration must also be a 2713 // definition (C++ [dcl.meaning]p1). 2714 if (!IsFunctionDefinition && !isFriend) { 2715 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2716 << D.getCXXScopeSpec().getRange(); 2717 NewFD->setInvalidDecl(); 2718 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2719 // The user tried to provide an out-of-line definition for a 2720 // function that is a member of a class or namespace, but there 2721 // was no such member function declared (C++ [class.mfct]p2, 2722 // C++ [namespace.memdef]p2). For example: 2723 // 2724 // class X { 2725 // void f() const; 2726 // }; 2727 // 2728 // void X::f() { } // ill-formed 2729 // 2730 // Complain about this problem, and attempt to suggest close 2731 // matches (e.g., those that differ only in cv-qualifiers and 2732 // whether the parameter types are references). 2733 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2734 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2735 NewFD->setInvalidDecl(); 2736 2737 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2738 true); 2739 assert(!Prev.isAmbiguous() && 2740 "Cannot have an ambiguity in previous-declaration lookup"); 2741 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2742 Func != FuncEnd; ++Func) { 2743 if (isa<FunctionDecl>(*Func) && 2744 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2745 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2746 } 2747 2748 PrevDecl = 0; 2749 } 2750 } 2751 2752 // Handle attributes. We need to have merged decls when handling attributes 2753 // (for example to check for conflicts, etc). 2754 // FIXME: This needs to happen before we merge declarations. Then, 2755 // let attribute merging cope with attribute conflicts. 2756 ProcessDeclAttributes(S, NewFD, D); 2757 2758 // attributes declared post-definition are currently ignored 2759 if (Redeclaration && PrevDecl) { 2760 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2761 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2762 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2763 Diag(Def->getLocation(), diag::note_previous_definition); 2764 } 2765 } 2766 2767 AddKnownFunctionAttributes(NewFD); 2768 2769 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2770 // If a function name is overloadable in C, then every function 2771 // with that name must be marked "overloadable". 2772 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2773 << Redeclaration << NewFD; 2774 if (PrevDecl) 2775 Diag(PrevDecl->getLocation(), 2776 diag::note_attribute_overloadable_prev_overload); 2777 NewFD->addAttr(::new (Context) OverloadableAttr()); 2778 } 2779 2780 // If this is a locally-scoped extern C function, update the 2781 // map of such names. 2782 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2783 && !NewFD->isInvalidDecl()) 2784 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2785 2786 // Set this FunctionDecl's range up to the right paren. 2787 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2788 2789 if (FunctionTemplate && NewFD->isInvalidDecl()) 2790 FunctionTemplate->setInvalidDecl(); 2791 2792 if (FunctionTemplate) 2793 return FunctionTemplate; 2794 2795 return NewFD; 2796} 2797 2798/// \brief Perform semantic checking of a new function declaration. 2799/// 2800/// Performs semantic analysis of the new function declaration 2801/// NewFD. This routine performs all semantic checking that does not 2802/// require the actual declarator involved in the declaration, and is 2803/// used both for the declaration of functions as they are parsed 2804/// (called via ActOnDeclarator) and for the declaration of functions 2805/// that have been instantiated via C++ template instantiation (called 2806/// via InstantiateDecl). 2807/// 2808/// This sets NewFD->isInvalidDecl() to true if there was an error. 2809void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2810 bool &Redeclaration, 2811 bool &OverloadableAttrRequired) { 2812 // If NewFD is already known erroneous, don't do any of this checking. 2813 if (NewFD->isInvalidDecl()) 2814 return; 2815 2816 if (NewFD->getResultType()->isVariablyModifiedType()) { 2817 // Functions returning a variably modified type violate C99 6.7.5.2p2 2818 // because all functions have linkage. 2819 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2820 return NewFD->setInvalidDecl(); 2821 } 2822 2823 if (NewFD->isMain(Context)) CheckMain(NewFD); 2824 2825 // Semantic checking for this function declaration (in isolation). 2826 if (getLangOptions().CPlusPlus) { 2827 // C++-specific checks. 2828 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2829 CheckConstructor(Constructor); 2830 } else if (isa<CXXDestructorDecl>(NewFD)) { 2831 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2832 QualType ClassType = Context.getTypeDeclType(Record); 2833 if (!ClassType->isDependentType()) { 2834 DeclarationName Name 2835 = Context.DeclarationNames.getCXXDestructorName( 2836 Context.getCanonicalType(ClassType)); 2837 if (NewFD->getDeclName() != Name) { 2838 Diag(NewFD->getLocation(), diag::err_destructor_name); 2839 return NewFD->setInvalidDecl(); 2840 } 2841 } 2842 Record->setUserDeclaredDestructor(true); 2843 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2844 // user-defined destructor. 2845 Record->setPOD(false); 2846 2847 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2848 // declared destructor. 2849 // FIXME: C++0x: don't do this for "= default" destructors 2850 Record->setHasTrivialDestructor(false); 2851 } else if (CXXConversionDecl *Conversion 2852 = dyn_cast<CXXConversionDecl>(NewFD)) 2853 ActOnConversionDeclarator(Conversion); 2854 2855 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2856 if (NewFD->isOverloadedOperator() && 2857 CheckOverloadedOperatorDeclaration(NewFD)) 2858 return NewFD->setInvalidDecl(); 2859 } 2860 2861 // C99 6.7.4p6: 2862 // [... ] For a function with external linkage, the following 2863 // restrictions apply: [...] If all of the file scope declarations 2864 // for a function in a translation unit include the inline 2865 // function specifier without extern, then the definition in that 2866 // translation unit is an inline definition. An inline definition 2867 // does not provide an external definition for the function, and 2868 // does not forbid an external definition in another translation 2869 // unit. 2870 // 2871 // Here we determine whether this function, in isolation, would be a 2872 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2873 // previous declarations. 2874 if (NewFD->isInline() && getLangOptions().C99 && 2875 NewFD->getStorageClass() == FunctionDecl::None && 2876 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2877 NewFD->setC99InlineDefinition(true); 2878 2879 // Check for a previous declaration of this name. 2880 if (!PrevDecl && NewFD->isExternC(Context)) { 2881 // Since we did not find anything by this name and we're declaring 2882 // an extern "C" function, look for a non-visible extern "C" 2883 // declaration with the same name. 2884 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2885 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2886 if (Pos != LocallyScopedExternalDecls.end()) 2887 PrevDecl = Pos->second; 2888 } 2889 2890 // Merge or overload the declaration with an existing declaration of 2891 // the same name, if appropriate. 2892 if (PrevDecl) { 2893 // Determine whether NewFD is an overload of PrevDecl or 2894 // a declaration that requires merging. If it's an overload, 2895 // there's no more work to do here; we'll just add the new 2896 // function to the scope. 2897 OverloadedFunctionDecl::function_iterator MatchedDecl; 2898 2899 if (!getLangOptions().CPlusPlus && 2900 AllowOverloadingOfFunction(PrevDecl, Context)) { 2901 OverloadableAttrRequired = true; 2902 2903 // Functions marked "overloadable" must have a prototype (that 2904 // we can't get through declaration merging). 2905 if (!NewFD->getType()->getAsFunctionProtoType()) { 2906 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2907 << NewFD; 2908 Redeclaration = true; 2909 2910 // Turn this into a variadic function with no parameters. 2911 QualType R = Context.getFunctionType( 2912 NewFD->getType()->getAsFunctionType()->getResultType(), 2913 0, 0, true, 0); 2914 NewFD->setType(R); 2915 return NewFD->setInvalidDecl(); 2916 } 2917 } 2918 2919 if (PrevDecl && 2920 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2921 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2922 Redeclaration = true; 2923 Decl *OldDecl = PrevDecl; 2924 2925 // If PrevDecl was an overloaded function, extract the 2926 // FunctionDecl that matched. 2927 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2928 OldDecl = *MatchedDecl; 2929 2930 // NewFD and OldDecl represent declarations that need to be 2931 // merged. 2932 if (MergeFunctionDecl(NewFD, OldDecl)) 2933 return NewFD->setInvalidDecl(); 2934 2935 if (FunctionTemplateDecl *OldTemplateDecl 2936 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2937 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2938 else { 2939 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2940 NewFD->setAccess(OldDecl->getAccess()); 2941 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2942 } 2943 } 2944 } 2945 2946 // In C++, check default arguments now that we have merged decls. Unless 2947 // the lexical context is the class, because in this case this is done 2948 // during delayed parsing anyway. 2949 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2950 CheckCXXDefaultArguments(NewFD); 2951} 2952 2953void Sema::CheckMain(FunctionDecl* FD) { 2954 // C++ [basic.start.main]p3: A program that declares main to be inline 2955 // or static is ill-formed. 2956 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2957 // shall not appear in a declaration of main. 2958 // static main is not an error under C99, but we should warn about it. 2959 bool isInline = FD->isInline(); 2960 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2961 if (isInline || isStatic) { 2962 unsigned diagID = diag::warn_unusual_main_decl; 2963 if (isInline || getLangOptions().CPlusPlus) 2964 diagID = diag::err_unusual_main_decl; 2965 2966 int which = isStatic + (isInline << 1) - 1; 2967 Diag(FD->getLocation(), diagID) << which; 2968 } 2969 2970 QualType T = FD->getType(); 2971 assert(T->isFunctionType() && "function decl is not of function type"); 2972 const FunctionType* FT = T->getAsFunctionType(); 2973 2974 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2975 // TODO: add a replacement fixit to turn the return type into 'int'. 2976 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2977 FD->setInvalidDecl(true); 2978 } 2979 2980 // Treat protoless main() as nullary. 2981 if (isa<FunctionNoProtoType>(FT)) return; 2982 2983 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2984 unsigned nparams = FTP->getNumArgs(); 2985 assert(FD->getNumParams() == nparams); 2986 2987 if (nparams > 3) { 2988 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2989 FD->setInvalidDecl(true); 2990 nparams = 3; 2991 } 2992 2993 // FIXME: a lot of the following diagnostics would be improved 2994 // if we had some location information about types. 2995 2996 QualType CharPP = 2997 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2998 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2999 3000 for (unsigned i = 0; i < nparams; ++i) { 3001 QualType AT = FTP->getArgType(i); 3002 3003 bool mismatch = true; 3004 3005 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3006 mismatch = false; 3007 else if (Expected[i] == CharPP) { 3008 // As an extension, the following forms are okay: 3009 // char const ** 3010 // char const * const * 3011 // char * const * 3012 3013 QualifierSet qs; 3014 const PointerType* PT; 3015 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3016 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3017 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3018 qs.removeConst(); 3019 mismatch = !qs.empty(); 3020 } 3021 } 3022 3023 if (mismatch) { 3024 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3025 // TODO: suggest replacing given type with expected type 3026 FD->setInvalidDecl(true); 3027 } 3028 } 3029 3030 if (nparams == 1 && !FD->isInvalidDecl()) { 3031 Diag(FD->getLocation(), diag::warn_main_one_arg); 3032 } 3033} 3034 3035bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3036 // FIXME: Need strict checking. In C89, we need to check for 3037 // any assignment, increment, decrement, function-calls, or 3038 // commas outside of a sizeof. In C99, it's the same list, 3039 // except that the aforementioned are allowed in unevaluated 3040 // expressions. Everything else falls under the 3041 // "may accept other forms of constant expressions" exception. 3042 // (We never end up here for C++, so the constant expression 3043 // rules there don't matter.) 3044 if (Init->isConstantInitializer(Context)) 3045 return false; 3046 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3047 << Init->getSourceRange(); 3048 return true; 3049} 3050 3051void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3052 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3053} 3054 3055/// AddInitializerToDecl - Adds the initializer Init to the 3056/// declaration dcl. If DirectInit is true, this is C++ direct 3057/// initialization rather than copy initialization. 3058void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3059 Decl *RealDecl = dcl.getAs<Decl>(); 3060 // If there is no declaration, there was an error parsing it. Just ignore 3061 // the initializer. 3062 if (RealDecl == 0) 3063 return; 3064 3065 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3066 // With declarators parsed the way they are, the parser cannot 3067 // distinguish between a normal initializer and a pure-specifier. 3068 // Thus this grotesque test. 3069 IntegerLiteral *IL; 3070 Expr *Init = static_cast<Expr *>(init.get()); 3071 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3072 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3073 if (Method->isVirtualAsWritten()) { 3074 Method->setPure(); 3075 3076 // A class is abstract if at least one function is pure virtual. 3077 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3078 } else if (!Method->isInvalidDecl()) { 3079 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3080 << Method->getDeclName() << Init->getSourceRange(); 3081 Method->setInvalidDecl(); 3082 } 3083 } else { 3084 Diag(Method->getLocation(), diag::err_member_function_initialization) 3085 << Method->getDeclName() << Init->getSourceRange(); 3086 Method->setInvalidDecl(); 3087 } 3088 return; 3089 } 3090 3091 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3092 if (!VDecl) { 3093 if (getLangOptions().CPlusPlus && 3094 RealDecl->getLexicalDeclContext()->isRecord() && 3095 isa<NamedDecl>(RealDecl)) 3096 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3097 << cast<NamedDecl>(RealDecl)->getDeclName(); 3098 else 3099 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3100 RealDecl->setInvalidDecl(); 3101 return; 3102 } 3103 3104 if (!VDecl->getType()->isArrayType() && 3105 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3106 diag::err_typecheck_decl_incomplete_type)) { 3107 RealDecl->setInvalidDecl(); 3108 return; 3109 } 3110 3111 const VarDecl *Def = 0; 3112 if (VDecl->getDefinition(Def)) { 3113 Diag(VDecl->getLocation(), diag::err_redefinition) 3114 << VDecl->getDeclName(); 3115 Diag(Def->getLocation(), diag::note_previous_definition); 3116 VDecl->setInvalidDecl(); 3117 return; 3118 } 3119 3120 // Take ownership of the expression, now that we're sure we have somewhere 3121 // to put it. 3122 Expr *Init = init.takeAs<Expr>(); 3123 assert(Init && "missing initializer"); 3124 3125 // Get the decls type and save a reference for later, since 3126 // CheckInitializerTypes may change it. 3127 QualType DclT = VDecl->getType(), SavT = DclT; 3128 if (VDecl->isBlockVarDecl()) { 3129 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3130 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3131 VDecl->setInvalidDecl(); 3132 } else if (!VDecl->isInvalidDecl()) { 3133 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3134 VDecl->getDeclName(), DirectInit)) 3135 VDecl->setInvalidDecl(); 3136 3137 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3138 // Don't check invalid declarations to avoid emitting useless diagnostics. 3139 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3140 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3141 CheckForConstantInitializer(Init, DclT); 3142 } 3143 } 3144 } else if (VDecl->isStaticDataMember() && 3145 VDecl->getLexicalDeclContext()->isRecord()) { 3146 // This is an in-class initialization for a static data member, e.g., 3147 // 3148 // struct S { 3149 // static const int value = 17; 3150 // }; 3151 3152 // Attach the initializer 3153 VDecl->setInit(Context, Init); 3154 3155 // C++ [class.mem]p4: 3156 // A member-declarator can contain a constant-initializer only 3157 // if it declares a static member (9.4) of const integral or 3158 // const enumeration type, see 9.4.2. 3159 QualType T = VDecl->getType(); 3160 if (!T->isDependentType() && 3161 (!Context.getCanonicalType(T).isConstQualified() || 3162 !T->isIntegralType())) { 3163 Diag(VDecl->getLocation(), diag::err_member_initialization) 3164 << VDecl->getDeclName() << Init->getSourceRange(); 3165 VDecl->setInvalidDecl(); 3166 } else { 3167 // C++ [class.static.data]p4: 3168 // If a static data member is of const integral or const 3169 // enumeration type, its declaration in the class definition 3170 // can specify a constant-initializer which shall be an 3171 // integral constant expression (5.19). 3172 if (!Init->isTypeDependent() && 3173 !Init->getType()->isIntegralType()) { 3174 // We have a non-dependent, non-integral or enumeration type. 3175 Diag(Init->getSourceRange().getBegin(), 3176 diag::err_in_class_initializer_non_integral_type) 3177 << Init->getType() << Init->getSourceRange(); 3178 VDecl->setInvalidDecl(); 3179 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3180 // Check whether the expression is a constant expression. 3181 llvm::APSInt Value; 3182 SourceLocation Loc; 3183 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3184 Diag(Loc, diag::err_in_class_initializer_non_constant) 3185 << Init->getSourceRange(); 3186 VDecl->setInvalidDecl(); 3187 } else if (!VDecl->getType()->isDependentType()) 3188 ImpCastExprToType(Init, VDecl->getType()); 3189 } 3190 } 3191 } else if (VDecl->isFileVarDecl()) { 3192 if (VDecl->getStorageClass() == VarDecl::Extern) 3193 Diag(VDecl->getLocation(), diag::warn_extern_init); 3194 if (!VDecl->isInvalidDecl()) 3195 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3196 VDecl->getDeclName(), DirectInit)) 3197 VDecl->setInvalidDecl(); 3198 3199 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3200 // Don't check invalid declarations to avoid emitting useless diagnostics. 3201 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3202 // C99 6.7.8p4. All file scoped initializers need to be constant. 3203 CheckForConstantInitializer(Init, DclT); 3204 } 3205 } 3206 // If the type changed, it means we had an incomplete type that was 3207 // completed by the initializer. For example: 3208 // int ary[] = { 1, 3, 5 }; 3209 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3210 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3211 VDecl->setType(DclT); 3212 Init->setType(DclT); 3213 } 3214 3215 Init = MaybeCreateCXXExprWithTemporaries(Init, 3216 /*ShouldDestroyTemporaries=*/true); 3217 // Attach the initializer to the decl. 3218 VDecl->setInit(Context, Init); 3219 3220 // If the previous declaration of VDecl was a tentative definition, 3221 // remove it from the set of tentative definitions. 3222 if (VDecl->getPreviousDeclaration() && 3223 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3224 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3225 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3226 } 3227 3228 return; 3229} 3230 3231void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3232 bool TypeContainsUndeducedAuto) { 3233 Decl *RealDecl = dcl.getAs<Decl>(); 3234 3235 // If there is no declaration, there was an error parsing it. Just ignore it. 3236 if (RealDecl == 0) 3237 return; 3238 3239 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3240 QualType Type = Var->getType(); 3241 3242 // Record tentative definitions. 3243 if (Var->isTentativeDefinition(Context)) { 3244 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3245 InsertPair = 3246 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3247 3248 // Keep the latest definition in the map. If we see 'int i; int i;' we 3249 // want the second one in the map. 3250 InsertPair.first->second = Var; 3251 3252 // However, for the list, we don't care about the order, just make sure 3253 // that there are no dupes for a given declaration name. 3254 if (InsertPair.second) 3255 TentativeDefinitionList.push_back(Var->getDeclName()); 3256 } 3257 3258 // C++ [dcl.init.ref]p3: 3259 // The initializer can be omitted for a reference only in a 3260 // parameter declaration (8.3.5), in the declaration of a 3261 // function return type, in the declaration of a class member 3262 // within its class declaration (9.2), and where the extern 3263 // specifier is explicitly used. 3264 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3265 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3266 << Var->getDeclName() 3267 << SourceRange(Var->getLocation(), Var->getLocation()); 3268 Var->setInvalidDecl(); 3269 return; 3270 } 3271 3272 // C++0x [dcl.spec.auto]p3 3273 if (TypeContainsUndeducedAuto) { 3274 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3275 << Var->getDeclName() << Type; 3276 Var->setInvalidDecl(); 3277 return; 3278 } 3279 3280 // C++ [dcl.init]p9: 3281 // 3282 // If no initializer is specified for an object, and the object 3283 // is of (possibly cv-qualified) non-POD class type (or array 3284 // thereof), the object shall be default-initialized; if the 3285 // object is of const-qualified type, the underlying class type 3286 // shall have a user-declared default constructor. 3287 if (getLangOptions().CPlusPlus) { 3288 QualType InitType = Type; 3289 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3290 InitType = Array->getElementType(); 3291 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 3292 InitType->isRecordType() && !InitType->isDependentType()) { 3293 CXXRecordDecl *RD = 3294 cast<CXXRecordDecl>(InitType->getAs<RecordType>()->getDecl()); 3295 CXXConstructorDecl *Constructor = 0; 3296 if (!RequireCompleteType(Var->getLocation(), InitType, 3297 diag::err_invalid_incomplete_type_use)) 3298 Constructor 3299 = PerformInitializationByConstructor(InitType, 0, 0, 3300 Var->getLocation(), 3301 SourceRange(Var->getLocation(), 3302 Var->getLocation()), 3303 Var->getDeclName(), 3304 IK_Default); 3305 if (!Constructor) 3306 Var->setInvalidDecl(); 3307 else { 3308 if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()) { 3309 if (InitializeVarWithConstructor(Var, Constructor, InitType, 3310 MultiExprArg(*this))) 3311 Var->setInvalidDecl(); 3312 } 3313 3314 FinalizeVarWithDestructor(Var, InitType); 3315 } 3316 } 3317 } 3318 3319#if 0 3320 // FIXME: Temporarily disabled because we are not properly parsing 3321 // linkage specifications on declarations, e.g., 3322 // 3323 // extern "C" const CGPoint CGPointerZero; 3324 // 3325 // C++ [dcl.init]p9: 3326 // 3327 // If no initializer is specified for an object, and the 3328 // object is of (possibly cv-qualified) non-POD class type (or 3329 // array thereof), the object shall be default-initialized; if 3330 // the object is of const-qualified type, the underlying class 3331 // type shall have a user-declared default 3332 // constructor. Otherwise, if no initializer is specified for 3333 // an object, the object and its subobjects, if any, have an 3334 // indeterminate initial value; if the object or any of its 3335 // subobjects are of const-qualified type, the program is 3336 // ill-formed. 3337 // 3338 // This isn't technically an error in C, so we don't diagnose it. 3339 // 3340 // FIXME: Actually perform the POD/user-defined default 3341 // constructor check. 3342 if (getLangOptions().CPlusPlus && 3343 Context.getCanonicalType(Type).isConstQualified() && 3344 !Var->hasExternalStorage()) 3345 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3346 << Var->getName() 3347 << SourceRange(Var->getLocation(), Var->getLocation()); 3348#endif 3349 } 3350} 3351 3352Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3353 DeclPtrTy *Group, 3354 unsigned NumDecls) { 3355 llvm::SmallVector<Decl*, 8> Decls; 3356 3357 if (DS.isTypeSpecOwned()) 3358 Decls.push_back((Decl*)DS.getTypeRep()); 3359 3360 for (unsigned i = 0; i != NumDecls; ++i) 3361 if (Decl *D = Group[i].getAs<Decl>()) 3362 Decls.push_back(D); 3363 3364 // Perform semantic analysis that depends on having fully processed both 3365 // the declarator and initializer. 3366 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3367 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3368 if (!IDecl) 3369 continue; 3370 QualType T = IDecl->getType(); 3371 3372 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3373 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3374 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3375 if (!IDecl->isInvalidDecl() && 3376 RequireCompleteType(IDecl->getLocation(), T, 3377 diag::err_typecheck_decl_incomplete_type)) 3378 IDecl->setInvalidDecl(); 3379 } 3380 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3381 // object that has file scope without an initializer, and without a 3382 // storage-class specifier or with the storage-class specifier "static", 3383 // constitutes a tentative definition. Note: A tentative definition with 3384 // external linkage is valid (C99 6.2.2p5). 3385 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3386 if (const IncompleteArrayType *ArrayT 3387 = Context.getAsIncompleteArrayType(T)) { 3388 if (RequireCompleteType(IDecl->getLocation(), 3389 ArrayT->getElementType(), 3390 diag::err_illegal_decl_array_incomplete_type)) 3391 IDecl->setInvalidDecl(); 3392 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3393 // C99 6.9.2p3: If the declaration of an identifier for an object is 3394 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3395 // declared type shall not be an incomplete type. 3396 // NOTE: code such as the following 3397 // static struct s; 3398 // struct s { int a; }; 3399 // is accepted by gcc. Hence here we issue a warning instead of 3400 // an error and we do not invalidate the static declaration. 3401 // NOTE: to avoid multiple warnings, only check the first declaration. 3402 if (IDecl->getPreviousDeclaration() == 0) 3403 RequireCompleteType(IDecl->getLocation(), T, 3404 diag::ext_typecheck_decl_incomplete_type); 3405 } 3406 } 3407 } 3408 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3409 Decls.data(), Decls.size())); 3410} 3411 3412 3413/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3414/// to introduce parameters into function prototype scope. 3415Sema::DeclPtrTy 3416Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3417 const DeclSpec &DS = D.getDeclSpec(); 3418 3419 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3420 VarDecl::StorageClass StorageClass = VarDecl::None; 3421 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3422 StorageClass = VarDecl::Register; 3423 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3424 Diag(DS.getStorageClassSpecLoc(), 3425 diag::err_invalid_storage_class_in_func_decl); 3426 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3427 } 3428 3429 if (D.getDeclSpec().isThreadSpecified()) 3430 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3431 3432 DiagnoseFunctionSpecifiers(D); 3433 3434 // Check that there are no default arguments inside the type of this 3435 // parameter (C++ only). 3436 if (getLangOptions().CPlusPlus) 3437 CheckExtraCXXDefaultArguments(D); 3438 3439 DeclaratorInfo *DInfo = 0; 3440 TagDecl *OwnedDecl = 0; 3441 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3442 &OwnedDecl); 3443 3444 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3445 // C++ [dcl.fct]p6: 3446 // Types shall not be defined in return or parameter types. 3447 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3448 << Context.getTypeDeclType(OwnedDecl); 3449 } 3450 3451 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3452 // Can this happen for params? We already checked that they don't conflict 3453 // among each other. Here they can only shadow globals, which is ok. 3454 IdentifierInfo *II = D.getIdentifier(); 3455 if (II) { 3456 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3457 if (PrevDecl->isTemplateParameter()) { 3458 // Maybe we will complain about the shadowed template parameter. 3459 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3460 // Just pretend that we didn't see the previous declaration. 3461 PrevDecl = 0; 3462 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3463 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3464 3465 // Recover by removing the name 3466 II = 0; 3467 D.SetIdentifier(0, D.getIdentifierLoc()); 3468 } 3469 } 3470 } 3471 3472 // Parameters can not be abstract class types. 3473 // For record types, this is done by the AbstractClassUsageDiagnoser once 3474 // the class has been completely parsed. 3475 if (!CurContext->isRecord() && 3476 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3477 diag::err_abstract_type_in_decl, 3478 AbstractParamType)) 3479 D.setInvalidType(true); 3480 3481 QualType T = adjustParameterType(parmDeclType); 3482 3483 ParmVarDecl *New; 3484 if (T == parmDeclType) // parameter type did not need adjustment 3485 New = ParmVarDecl::Create(Context, CurContext, 3486 D.getIdentifierLoc(), II, 3487 parmDeclType, DInfo, StorageClass, 3488 0); 3489 else // keep track of both the adjusted and unadjusted types 3490 New = OriginalParmVarDecl::Create(Context, CurContext, 3491 D.getIdentifierLoc(), II, T, DInfo, 3492 parmDeclType, StorageClass, 0); 3493 3494 if (D.isInvalidType()) 3495 New->setInvalidDecl(); 3496 3497 // Parameter declarators cannot be interface types. All ObjC objects are 3498 // passed by reference. 3499 if (T->isObjCInterfaceType()) { 3500 Diag(D.getIdentifierLoc(), 3501 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3502 New->setInvalidDecl(); 3503 } 3504 3505 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3506 if (D.getCXXScopeSpec().isSet()) { 3507 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3508 << D.getCXXScopeSpec().getRange(); 3509 New->setInvalidDecl(); 3510 } 3511 3512 // Add the parameter declaration into this scope. 3513 S->AddDecl(DeclPtrTy::make(New)); 3514 if (II) 3515 IdResolver.AddDecl(New); 3516 3517 ProcessDeclAttributes(S, New, D); 3518 3519 if (New->hasAttr<BlocksAttr>()) { 3520 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3521 } 3522 return DeclPtrTy::make(New); 3523} 3524 3525void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3526 SourceLocation LocAfterDecls) { 3527 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3528 "Not a function declarator!"); 3529 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3530 3531 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3532 // for a K&R function. 3533 if (!FTI.hasPrototype) { 3534 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3535 --i; 3536 if (FTI.ArgInfo[i].Param == 0) { 3537 std::string Code = " int "; 3538 Code += FTI.ArgInfo[i].Ident->getName(); 3539 Code += ";\n"; 3540 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3541 << FTI.ArgInfo[i].Ident 3542 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3543 3544 // Implicitly declare the argument as type 'int' for lack of a better 3545 // type. 3546 DeclSpec DS; 3547 const char* PrevSpec; // unused 3548 unsigned DiagID; // unused 3549 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3550 PrevSpec, DiagID); 3551 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3552 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3553 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3554 } 3555 } 3556 } 3557} 3558 3559Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3560 Declarator &D) { 3561 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3562 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3563 "Not a function declarator!"); 3564 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3565 3566 if (FTI.hasPrototype) { 3567 // FIXME: Diagnose arguments without names in C. 3568 } 3569 3570 Scope *ParentScope = FnBodyScope->getParent(); 3571 3572 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3573 MultiTemplateParamsArg(*this), 3574 /*IsFunctionDefinition=*/true); 3575 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3576} 3577 3578Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3579 if (!D) 3580 return D; 3581 FunctionDecl *FD = 0; 3582 3583 if (FunctionTemplateDecl *FunTmpl 3584 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3585 FD = FunTmpl->getTemplatedDecl(); 3586 else 3587 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3588 3589 CurFunctionNeedsScopeChecking = false; 3590 3591 // See if this is a redefinition. 3592 const FunctionDecl *Definition; 3593 if (FD->getBody(Definition)) { 3594 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3595 Diag(Definition->getLocation(), diag::note_previous_definition); 3596 } 3597 3598 // Builtin functions cannot be defined. 3599 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3600 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3601 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3602 FD->setInvalidDecl(); 3603 } 3604 } 3605 3606 // The return type of a function definition must be complete 3607 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3608 QualType ResultType = FD->getResultType(); 3609 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3610 !FD->isInvalidDecl() && 3611 RequireCompleteType(FD->getLocation(), ResultType, 3612 diag::err_func_def_incomplete_result)) 3613 FD->setInvalidDecl(); 3614 3615 // GNU warning -Wmissing-prototypes: 3616 // Warn if a global function is defined without a previous 3617 // prototype declaration. This warning is issued even if the 3618 // definition itself provides a prototype. The aim is to detect 3619 // global functions that fail to be declared in header files. 3620 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3621 !FD->isMain(Context)) { 3622 bool MissingPrototype = true; 3623 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3624 Prev; Prev = Prev->getPreviousDeclaration()) { 3625 // Ignore any declarations that occur in function or method 3626 // scope, because they aren't visible from the header. 3627 if (Prev->getDeclContext()->isFunctionOrMethod()) 3628 continue; 3629 3630 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3631 break; 3632 } 3633 3634 if (MissingPrototype) 3635 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3636 } 3637 3638 if (FnBodyScope) 3639 PushDeclContext(FnBodyScope, FD); 3640 3641 // Check the validity of our function parameters 3642 CheckParmsForFunctionDef(FD); 3643 3644 // Introduce our parameters into the function scope 3645 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3646 ParmVarDecl *Param = FD->getParamDecl(p); 3647 Param->setOwningFunction(FD); 3648 3649 // If this has an identifier, add it to the scope stack. 3650 if (Param->getIdentifier() && FnBodyScope) 3651 PushOnScopeChains(Param, FnBodyScope); 3652 } 3653 3654 // Checking attributes of current function definition 3655 // dllimport attribute. 3656 if (FD->getAttr<DLLImportAttr>() && 3657 (!FD->getAttr<DLLExportAttr>())) { 3658 // dllimport attribute cannot be applied to definition. 3659 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3660 Diag(FD->getLocation(), 3661 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3662 << "dllimport"; 3663 FD->setInvalidDecl(); 3664 return DeclPtrTy::make(FD); 3665 } else { 3666 // If a symbol previously declared dllimport is later defined, the 3667 // attribute is ignored in subsequent references, and a warning is 3668 // emitted. 3669 Diag(FD->getLocation(), 3670 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3671 << FD->getNameAsCString() << "dllimport"; 3672 } 3673 } 3674 return DeclPtrTy::make(FD); 3675} 3676 3677Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3678 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3679} 3680 3681Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3682 bool IsInstantiation) { 3683 Decl *dcl = D.getAs<Decl>(); 3684 Stmt *Body = BodyArg.takeAs<Stmt>(); 3685 3686 FunctionDecl *FD = 0; 3687 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3688 if (FunTmpl) 3689 FD = FunTmpl->getTemplatedDecl(); 3690 else 3691 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3692 3693 if (FD) { 3694 FD->setBody(Body); 3695 if (FD->isMain(Context)) 3696 // C and C++ allow for main to automagically return 0. 3697 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3698 FD->setHasImplicitReturnZero(true); 3699 else 3700 CheckFallThroughForFunctionDef(FD, Body); 3701 3702 if (!FD->isInvalidDecl()) 3703 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3704 3705 // C++ [basic.def.odr]p2: 3706 // [...] A virtual member function is used if it is not pure. [...] 3707 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3708 if (Method->isVirtual() && !Method->isPure()) 3709 MarkDeclarationReferenced(Method->getLocation(), Method); 3710 3711 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3712 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3713 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3714 MD->setBody(Body); 3715 CheckFallThroughForFunctionDef(MD, Body); 3716 MD->setEndLoc(Body->getLocEnd()); 3717 3718 if (!MD->isInvalidDecl()) 3719 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3720 } else { 3721 Body->Destroy(Context); 3722 return DeclPtrTy(); 3723 } 3724 if (!IsInstantiation) 3725 PopDeclContext(); 3726 3727 // Verify and clean out per-function state. 3728 3729 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3730 3731 // Check goto/label use. 3732 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3733 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3734 LabelStmt *L = I->second; 3735 3736 // Verify that we have no forward references left. If so, there was a goto 3737 // or address of a label taken, but no definition of it. Label fwd 3738 // definitions are indicated with a null substmt. 3739 if (L->getSubStmt() != 0) 3740 continue; 3741 3742 // Emit error. 3743 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3744 3745 // At this point, we have gotos that use the bogus label. Stitch it into 3746 // the function body so that they aren't leaked and that the AST is well 3747 // formed. 3748 if (Body == 0) { 3749 // The whole function wasn't parsed correctly, just delete this. 3750 L->Destroy(Context); 3751 continue; 3752 } 3753 3754 // Otherwise, the body is valid: we want to stitch the label decl into the 3755 // function somewhere so that it is properly owned and so that the goto 3756 // has a valid target. Do this by creating a new compound stmt with the 3757 // label in it. 3758 3759 // Give the label a sub-statement. 3760 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3761 3762 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3763 cast<CXXTryStmt>(Body)->getTryBlock() : 3764 cast<CompoundStmt>(Body); 3765 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3766 Elements.push_back(L); 3767 Compound->setStmts(Context, &Elements[0], Elements.size()); 3768 } 3769 FunctionLabelMap.clear(); 3770 3771 if (!Body) return D; 3772 3773 // Verify that that gotos and switch cases don't jump into scopes illegally. 3774 if (CurFunctionNeedsScopeChecking) 3775 DiagnoseInvalidJumps(Body); 3776 3777 // C++ constructors that have function-try-blocks can't have return 3778 // statements in the handlers of that block. (C++ [except.handle]p14) 3779 // Verify this. 3780 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3781 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3782 3783 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3784 computeBaseOrMembersToDestroy(Destructor); 3785 return D; 3786} 3787 3788/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3789/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3790NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3791 IdentifierInfo &II, Scope *S) { 3792 // Before we produce a declaration for an implicitly defined 3793 // function, see whether there was a locally-scoped declaration of 3794 // this name as a function or variable. If so, use that 3795 // (non-visible) declaration, and complain about it. 3796 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3797 = LocallyScopedExternalDecls.find(&II); 3798 if (Pos != LocallyScopedExternalDecls.end()) { 3799 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3800 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3801 return Pos->second; 3802 } 3803 3804 // Extension in C99. Legal in C90, but warn about it. 3805 if (getLangOptions().C99) 3806 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3807 else 3808 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3809 3810 // FIXME: handle stuff like: 3811 // void foo() { extern float X(); } 3812 // void bar() { X(); } <-- implicit decl for X in another scope. 3813 3814 // Set a Declarator for the implicit definition: int foo(); 3815 const char *Dummy; 3816 DeclSpec DS; 3817 unsigned DiagID; 3818 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3819 Error = Error; // Silence warning. 3820 assert(!Error && "Error setting up implicit decl!"); 3821 Declarator D(DS, Declarator::BlockContext); 3822 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3823 0, 0, false, SourceLocation(), 3824 false, 0,0,0, Loc, Loc, D), 3825 SourceLocation()); 3826 D.SetIdentifier(&II, Loc); 3827 3828 // Insert this function into translation-unit scope. 3829 3830 DeclContext *PrevDC = CurContext; 3831 CurContext = Context.getTranslationUnitDecl(); 3832 3833 FunctionDecl *FD = 3834 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3835 FD->setImplicit(); 3836 3837 CurContext = PrevDC; 3838 3839 AddKnownFunctionAttributes(FD); 3840 3841 return FD; 3842} 3843 3844/// \brief Adds any function attributes that we know a priori based on 3845/// the declaration of this function. 3846/// 3847/// These attributes can apply both to implicitly-declared builtins 3848/// (like __builtin___printf_chk) or to library-declared functions 3849/// like NSLog or printf. 3850void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3851 if (FD->isInvalidDecl()) 3852 return; 3853 3854 // If this is a built-in function, map its builtin attributes to 3855 // actual attributes. 3856 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3857 // Handle printf-formatting attributes. 3858 unsigned FormatIdx; 3859 bool HasVAListArg; 3860 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3861 if (!FD->getAttr<FormatAttr>()) 3862 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3863 HasVAListArg ? 0 : FormatIdx + 2)); 3864 } 3865 3866 // Mark const if we don't care about errno and that is the only 3867 // thing preventing the function from being const. This allows 3868 // IRgen to use LLVM intrinsics for such functions. 3869 if (!getLangOptions().MathErrno && 3870 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3871 if (!FD->getAttr<ConstAttr>()) 3872 FD->addAttr(::new (Context) ConstAttr()); 3873 } 3874 3875 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3876 FD->addAttr(::new (Context) NoReturnAttr()); 3877 } 3878 3879 IdentifierInfo *Name = FD->getIdentifier(); 3880 if (!Name) 3881 return; 3882 if ((!getLangOptions().CPlusPlus && 3883 FD->getDeclContext()->isTranslationUnit()) || 3884 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3885 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3886 LinkageSpecDecl::lang_c)) { 3887 // Okay: this could be a libc/libm/Objective-C function we know 3888 // about. 3889 } else 3890 return; 3891 3892 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3893 // FIXME: NSLog and NSLogv should be target specific 3894 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3895 // FIXME: We known better than our headers. 3896 const_cast<FormatAttr *>(Format)->setType("printf"); 3897 } else 3898 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3899 Name->isStr("NSLogv") ? 0 : 2)); 3900 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3901 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3902 // target-specific builtins, perhaps? 3903 if (!FD->getAttr<FormatAttr>()) 3904 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3905 Name->isStr("vasprintf") ? 0 : 3)); 3906 } 3907} 3908 3909TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3910 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3911 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3912 3913 // Scope manipulation handled by caller. 3914 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3915 D.getIdentifierLoc(), 3916 D.getIdentifier(), 3917 T); 3918 3919 if (const TagType *TT = T->getAs<TagType>()) { 3920 TagDecl *TD = TT->getDecl(); 3921 3922 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3923 // keep track of the TypedefDecl. 3924 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3925 TD->setTypedefForAnonDecl(NewTD); 3926 } 3927 3928 if (D.isInvalidType()) 3929 NewTD->setInvalidDecl(); 3930 return NewTD; 3931} 3932 3933 3934/// \brief Determine whether a tag with a given kind is acceptable 3935/// as a redeclaration of the given tag declaration. 3936/// 3937/// \returns true if the new tag kind is acceptable, false otherwise. 3938bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3939 TagDecl::TagKind NewTag, 3940 SourceLocation NewTagLoc, 3941 const IdentifierInfo &Name) { 3942 // C++ [dcl.type.elab]p3: 3943 // The class-key or enum keyword present in the 3944 // elaborated-type-specifier shall agree in kind with the 3945 // declaration to which the name in theelaborated-type-specifier 3946 // refers. This rule also applies to the form of 3947 // elaborated-type-specifier that declares a class-name or 3948 // friend class since it can be construed as referring to the 3949 // definition of the class. Thus, in any 3950 // elaborated-type-specifier, the enum keyword shall be used to 3951 // refer to an enumeration (7.2), the union class-keyshall be 3952 // used to refer to a union (clause 9), and either the class or 3953 // struct class-key shall be used to refer to a class (clause 9) 3954 // declared using the class or struct class-key. 3955 TagDecl::TagKind OldTag = Previous->getTagKind(); 3956 if (OldTag == NewTag) 3957 return true; 3958 3959 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3960 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3961 // Warn about the struct/class tag mismatch. 3962 bool isTemplate = false; 3963 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3964 isTemplate = Record->getDescribedClassTemplate(); 3965 3966 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3967 << (NewTag == TagDecl::TK_class) 3968 << isTemplate << &Name 3969 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3970 OldTag == TagDecl::TK_class? "class" : "struct"); 3971 Diag(Previous->getLocation(), diag::note_previous_use); 3972 return true; 3973 } 3974 return false; 3975} 3976 3977/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3978/// former case, Name will be non-null. In the later case, Name will be null. 3979/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3980/// reference/declaration/definition of a tag. 3981Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3982 SourceLocation KWLoc, const CXXScopeSpec &SS, 3983 IdentifierInfo *Name, SourceLocation NameLoc, 3984 AttributeList *Attr, AccessSpecifier AS, 3985 MultiTemplateParamsArg TemplateParameterLists, 3986 bool &OwnedDecl) { 3987 // If this is not a definition, it must have a name. 3988 assert((Name != 0 || TUK == TUK_Definition) && 3989 "Nameless record must be a definition!"); 3990 3991 OwnedDecl = false; 3992 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 3993 3994 if (TUK != TUK_Reference) { 3995 if (TemplateParameterList *TemplateParams 3996 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3997 (TemplateParameterList**)TemplateParameterLists.get(), 3998 TemplateParameterLists.size())) { 3999 if (TemplateParams->size() > 0) { 4000 // This is a declaration or definition of a class template (which may 4001 // be a member of another template). 4002 OwnedDecl = false; 4003 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4004 SS, Name, NameLoc, Attr, 4005 TemplateParams, 4006 AS); 4007 TemplateParameterLists.release(); 4008 return Result.get(); 4009 } else { 4010 // FIXME: diagnose the extraneous 'template<>', once we recover 4011 // slightly better in ParseTemplate.cpp from bogus template 4012 // parameters. 4013 } 4014 } 4015 } 4016 4017 DeclContext *SearchDC = CurContext; 4018 DeclContext *DC = CurContext; 4019 NamedDecl *PrevDecl = 0; 4020 4021 bool Invalid = false; 4022 4023 if (Name && SS.isNotEmpty()) { 4024 // We have a nested-name tag ('struct foo::bar'). 4025 4026 // Check for invalid 'foo::'. 4027 if (SS.isInvalid()) { 4028 Name = 0; 4029 goto CreateNewDecl; 4030 } 4031 4032 if (RequireCompleteDeclContext(SS)) 4033 return DeclPtrTy::make((Decl *)0); 4034 4035 DC = computeDeclContext(SS, true); 4036 SearchDC = DC; 4037 // Look-up name inside 'foo::'. 4038 PrevDecl 4039 = dyn_cast_or_null<TagDecl>( 4040 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4041 4042 // A tag 'foo::bar' must already exist. 4043 if (PrevDecl == 0) { 4044 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4045 Name = 0; 4046 Invalid = true; 4047 goto CreateNewDecl; 4048 } 4049 } else if (Name) { 4050 // If this is a named struct, check to see if there was a previous forward 4051 // declaration or definition. 4052 // FIXME: We're looking into outer scopes here, even when we 4053 // shouldn't be. Doing so can result in ambiguities that we 4054 // shouldn't be diagnosing. 4055 LookupResult R = LookupName(S, Name, LookupTagName, 4056 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4057 if (R.isAmbiguous()) { 4058 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4059 // FIXME: This is not best way to recover from case like: 4060 // 4061 // struct S s; 4062 // 4063 // causes needless "incomplete type" error later. 4064 Name = 0; 4065 PrevDecl = 0; 4066 Invalid = true; 4067 } else 4068 PrevDecl = R; 4069 4070 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4071 // FIXME: This makes sure that we ignore the contexts associated 4072 // with C structs, unions, and enums when looking for a matching 4073 // tag declaration or definition. See the similar lookup tweak 4074 // in Sema::LookupName; is there a better way to deal with this? 4075 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4076 SearchDC = SearchDC->getParent(); 4077 } 4078 } 4079 4080 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4081 // Maybe we will complain about the shadowed template parameter. 4082 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4083 // Just pretend that we didn't see the previous declaration. 4084 PrevDecl = 0; 4085 } 4086 4087 if (PrevDecl) { 4088 // Check whether the previous declaration is usable. 4089 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4090 4091 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4092 // If this is a use of a previous tag, or if the tag is already declared 4093 // in the same scope (so that the definition/declaration completes or 4094 // rementions the tag), reuse the decl. 4095 if (TUK == TUK_Reference || TUK == TUK_Friend || 4096 isDeclInScope(PrevDecl, SearchDC, S)) { 4097 // Make sure that this wasn't declared as an enum and now used as a 4098 // struct or something similar. 4099 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4100 bool SafeToContinue 4101 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4102 Kind != TagDecl::TK_enum); 4103 if (SafeToContinue) 4104 Diag(KWLoc, diag::err_use_with_wrong_tag) 4105 << Name 4106 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4107 PrevTagDecl->getKindName()); 4108 else 4109 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4110 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4111 4112 if (SafeToContinue) 4113 Kind = PrevTagDecl->getTagKind(); 4114 else { 4115 // Recover by making this an anonymous redefinition. 4116 Name = 0; 4117 PrevDecl = 0; 4118 Invalid = true; 4119 } 4120 } 4121 4122 if (!Invalid) { 4123 // If this is a use, just return the declaration we found. 4124 4125 // FIXME: In the future, return a variant or some other clue 4126 // for the consumer of this Decl to know it doesn't own it. 4127 // For our current ASTs this shouldn't be a problem, but will 4128 // need to be changed with DeclGroups. 4129 if (TUK == TUK_Reference) 4130 return DeclPtrTy::make(PrevDecl); 4131 4132 // If this is a friend, make sure we create the new 4133 // declaration in the appropriate semantic context. 4134 if (TUK == TUK_Friend) 4135 SearchDC = PrevDecl->getDeclContext(); 4136 4137 // Diagnose attempts to redefine a tag. 4138 if (TUK == TUK_Definition) { 4139 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4140 Diag(NameLoc, diag::err_redefinition) << Name; 4141 Diag(Def->getLocation(), diag::note_previous_definition); 4142 // If this is a redefinition, recover by making this 4143 // struct be anonymous, which will make any later 4144 // references get the previous definition. 4145 Name = 0; 4146 PrevDecl = 0; 4147 Invalid = true; 4148 } else { 4149 // If the type is currently being defined, complain 4150 // about a nested redefinition. 4151 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4152 if (Tag->isBeingDefined()) { 4153 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4154 Diag(PrevTagDecl->getLocation(), 4155 diag::note_previous_definition); 4156 Name = 0; 4157 PrevDecl = 0; 4158 Invalid = true; 4159 } 4160 } 4161 4162 // Okay, this is definition of a previously declared or referenced 4163 // tag PrevDecl. We're going to create a new Decl for it. 4164 } 4165 } 4166 // If we get here we have (another) forward declaration or we 4167 // have a definition. Just create a new decl. 4168 4169 } else { 4170 // If we get here, this is a definition of a new tag type in a nested 4171 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4172 // new decl/type. We set PrevDecl to NULL so that the entities 4173 // have distinct types. 4174 PrevDecl = 0; 4175 } 4176 // If we get here, we're going to create a new Decl. If PrevDecl 4177 // is non-NULL, it's a definition of the tag declared by 4178 // PrevDecl. If it's NULL, we have a new definition. 4179 } else { 4180 // PrevDecl is a namespace, template, or anything else 4181 // that lives in the IDNS_Tag identifier namespace. 4182 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4183 // The tag name clashes with a namespace name, issue an error and 4184 // recover by making this tag be anonymous. 4185 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4186 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4187 Name = 0; 4188 PrevDecl = 0; 4189 Invalid = true; 4190 } else { 4191 // The existing declaration isn't relevant to us; we're in a 4192 // new scope, so clear out the previous declaration. 4193 PrevDecl = 0; 4194 } 4195 } 4196 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4197 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4198 // C++ [basic.scope.pdecl]p5: 4199 // -- for an elaborated-type-specifier of the form 4200 // 4201 // class-key identifier 4202 // 4203 // if the elaborated-type-specifier is used in the 4204 // decl-specifier-seq or parameter-declaration-clause of a 4205 // function defined in namespace scope, the identifier is 4206 // declared as a class-name in the namespace that contains 4207 // the declaration; otherwise, except as a friend 4208 // declaration, the identifier is declared in the smallest 4209 // non-class, non-function-prototype scope that contains the 4210 // declaration. 4211 // 4212 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4213 // C structs and unions. 4214 // 4215 // GNU C also supports this behavior as part of its incomplete 4216 // enum types extension, while GNU C++ does not. 4217 // 4218 // Find the context where we'll be declaring the tag. 4219 // FIXME: We would like to maintain the current DeclContext as the 4220 // lexical context, 4221 while (SearchDC->isRecord()) 4222 SearchDC = SearchDC->getParent(); 4223 4224 // Find the scope where we'll be declaring the tag. 4225 while (S->isClassScope() || 4226 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4227 ((S->getFlags() & Scope::DeclScope) == 0) || 4228 (S->getEntity() && 4229 ((DeclContext *)S->getEntity())->isTransparentContext())) 4230 S = S->getParent(); 4231 4232 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4233 // C++ [namespace.memdef]p3: 4234 // If a friend declaration in a non-local class first declares a 4235 // class or function, the friend class or function is a member of 4236 // the innermost enclosing namespace. 4237 while (!SearchDC->isFileContext()) 4238 SearchDC = SearchDC->getParent(); 4239 4240 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4241 while (S->getEntity() != SearchDC) 4242 S = S->getParent(); 4243 } 4244 4245CreateNewDecl: 4246 4247 // If there is an identifier, use the location of the identifier as the 4248 // location of the decl, otherwise use the location of the struct/union 4249 // keyword. 4250 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4251 4252 // Otherwise, create a new declaration. If there is a previous 4253 // declaration of the same entity, the two will be linked via 4254 // PrevDecl. 4255 TagDecl *New; 4256 4257 if (Kind == TagDecl::TK_enum) { 4258 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4259 // enum X { A, B, C } D; D should chain to X. 4260 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4261 cast_or_null<EnumDecl>(PrevDecl)); 4262 // If this is an undefined enum, warn. 4263 if (TUK != TUK_Definition && !Invalid) { 4264 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4265 : diag::ext_forward_ref_enum; 4266 Diag(Loc, DK); 4267 } 4268 } else { 4269 // struct/union/class 4270 4271 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4272 // struct X { int A; } D; D should chain to X. 4273 if (getLangOptions().CPlusPlus) 4274 // FIXME: Look for a way to use RecordDecl for simple structs. 4275 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4276 cast_or_null<CXXRecordDecl>(PrevDecl)); 4277 else 4278 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4279 cast_or_null<RecordDecl>(PrevDecl)); 4280 } 4281 4282 if (Kind != TagDecl::TK_enum) { 4283 // Handle #pragma pack: if the #pragma pack stack has non-default 4284 // alignment, make up a packed attribute for this decl. These 4285 // attributes are checked when the ASTContext lays out the 4286 // structure. 4287 // 4288 // It is important for implementing the correct semantics that this 4289 // happen here (in act on tag decl). The #pragma pack stack is 4290 // maintained as a result of parser callbacks which can occur at 4291 // many points during the parsing of a struct declaration (because 4292 // the #pragma tokens are effectively skipped over during the 4293 // parsing of the struct). 4294 if (unsigned Alignment = getPragmaPackAlignment()) 4295 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4296 } 4297 4298 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4299 // C++ [dcl.typedef]p3: 4300 // [...] Similarly, in a given scope, a class or enumeration 4301 // shall not be declared with the same name as a typedef-name 4302 // that is declared in that scope and refers to a type other 4303 // than the class or enumeration itself. 4304 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4305 TypedefDecl *PrevTypedef = 0; 4306 if (Lookup.getKind() == LookupResult::Found) 4307 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4308 4309 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4310 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4311 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4312 Diag(Loc, diag::err_tag_definition_of_typedef) 4313 << Context.getTypeDeclType(New) 4314 << PrevTypedef->getUnderlyingType(); 4315 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4316 Invalid = true; 4317 } 4318 } 4319 4320 if (Invalid) 4321 New->setInvalidDecl(); 4322 4323 if (Attr) 4324 ProcessDeclAttributeList(S, New, Attr); 4325 4326 // If we're declaring or defining a tag in function prototype scope 4327 // in C, note that this type can only be used within the function. 4328 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4329 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4330 4331 // Set the lexical context. If the tag has a C++ scope specifier, the 4332 // lexical context will be different from the semantic context. 4333 New->setLexicalDeclContext(CurContext); 4334 4335 // Mark this as a friend decl if applicable. 4336 if (TUK == TUK_Friend) 4337 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4338 4339 // Set the access specifier. 4340 if (!Invalid && TUK != TUK_Friend) 4341 SetMemberAccessSpecifier(New, PrevDecl, AS); 4342 4343 if (TUK == TUK_Definition) 4344 New->startDefinition(); 4345 4346 // If this has an identifier, add it to the scope stack. 4347 if (TUK == TUK_Friend) { 4348 // We might be replacing an existing declaration in the lookup tables; 4349 // if so, borrow its access specifier. 4350 if (PrevDecl) 4351 New->setAccess(PrevDecl->getAccess()); 4352 4353 // Friend tag decls are visible in fairly strange ways. 4354 if (!CurContext->isDependentContext()) { 4355 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4356 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4357 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4358 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4359 } 4360 } else if (Name) { 4361 S = getNonFieldDeclScope(S); 4362 PushOnScopeChains(New, S); 4363 } else { 4364 CurContext->addDecl(New); 4365 } 4366 4367 // If this is the C FILE type, notify the AST context. 4368 if (IdentifierInfo *II = New->getIdentifier()) 4369 if (!New->isInvalidDecl() && 4370 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4371 II->isStr("FILE")) 4372 Context.setFILEDecl(New); 4373 4374 OwnedDecl = true; 4375 return DeclPtrTy::make(New); 4376} 4377 4378void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4379 AdjustDeclIfTemplate(TagD); 4380 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4381 4382 // Enter the tag context. 4383 PushDeclContext(S, Tag); 4384 4385 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4386 FieldCollector->StartClass(); 4387 4388 if (Record->getIdentifier()) { 4389 // C++ [class]p2: 4390 // [...] The class-name is also inserted into the scope of the 4391 // class itself; this is known as the injected-class-name. For 4392 // purposes of access checking, the injected-class-name is treated 4393 // as if it were a public member name. 4394 CXXRecordDecl *InjectedClassName 4395 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4396 CurContext, Record->getLocation(), 4397 Record->getIdentifier(), 4398 Record->getTagKeywordLoc(), 4399 Record); 4400 InjectedClassName->setImplicit(); 4401 InjectedClassName->setAccess(AS_public); 4402 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4403 InjectedClassName->setDescribedClassTemplate(Template); 4404 PushOnScopeChains(InjectedClassName, S); 4405 assert(InjectedClassName->isInjectedClassName() && 4406 "Broken injected-class-name"); 4407 } 4408 } 4409} 4410 4411void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4412 SourceLocation RBraceLoc) { 4413 AdjustDeclIfTemplate(TagD); 4414 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4415 Tag->setRBraceLoc(RBraceLoc); 4416 4417 if (isa<CXXRecordDecl>(Tag)) 4418 FieldCollector->FinishClass(); 4419 4420 // Exit this scope of this tag's definition. 4421 PopDeclContext(); 4422 4423 // Notify the consumer that we've defined a tag. 4424 Consumer.HandleTagDeclDefinition(Tag); 4425} 4426 4427// Note that FieldName may be null for anonymous bitfields. 4428bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4429 QualType FieldTy, const Expr *BitWidth, 4430 bool *ZeroWidth) { 4431 // Default to true; that shouldn't confuse checks for emptiness 4432 if (ZeroWidth) 4433 *ZeroWidth = true; 4434 4435 // C99 6.7.2.1p4 - verify the field type. 4436 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4437 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4438 // Handle incomplete types with specific error. 4439 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4440 return true; 4441 if (FieldName) 4442 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4443 << FieldName << FieldTy << BitWidth->getSourceRange(); 4444 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4445 << FieldTy << BitWidth->getSourceRange(); 4446 } 4447 4448 // If the bit-width is type- or value-dependent, don't try to check 4449 // it now. 4450 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4451 return false; 4452 4453 llvm::APSInt Value; 4454 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4455 return true; 4456 4457 if (Value != 0 && ZeroWidth) 4458 *ZeroWidth = false; 4459 4460 // Zero-width bitfield is ok for anonymous field. 4461 if (Value == 0 && FieldName) 4462 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4463 4464 if (Value.isSigned() && Value.isNegative()) { 4465 if (FieldName) 4466 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4467 << FieldName << Value.toString(10); 4468 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4469 << Value.toString(10); 4470 } 4471 4472 if (!FieldTy->isDependentType()) { 4473 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4474 if (Value.getZExtValue() > TypeSize) { 4475 if (FieldName) 4476 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4477 << FieldName << (unsigned)TypeSize; 4478 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4479 << (unsigned)TypeSize; 4480 } 4481 } 4482 4483 return false; 4484} 4485 4486/// ActOnField - Each field of a struct/union/class is passed into this in order 4487/// to create a FieldDecl object for it. 4488Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4489 SourceLocation DeclStart, 4490 Declarator &D, ExprTy *BitfieldWidth) { 4491 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4492 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4493 AS_public); 4494 return DeclPtrTy::make(Res); 4495} 4496 4497/// HandleField - Analyze a field of a C struct or a C++ data member. 4498/// 4499FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4500 SourceLocation DeclStart, 4501 Declarator &D, Expr *BitWidth, 4502 AccessSpecifier AS) { 4503 IdentifierInfo *II = D.getIdentifier(); 4504 SourceLocation Loc = DeclStart; 4505 if (II) Loc = D.getIdentifierLoc(); 4506 4507 DeclaratorInfo *DInfo = 0; 4508 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4509 if (getLangOptions().CPlusPlus) 4510 CheckExtraCXXDefaultArguments(D); 4511 4512 DiagnoseFunctionSpecifiers(D); 4513 4514 if (D.getDeclSpec().isThreadSpecified()) 4515 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4516 4517 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4518 4519 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4520 // Maybe we will complain about the shadowed template parameter. 4521 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4522 // Just pretend that we didn't see the previous declaration. 4523 PrevDecl = 0; 4524 } 4525 4526 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4527 PrevDecl = 0; 4528 4529 bool Mutable 4530 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4531 SourceLocation TSSL = D.getSourceRange().getBegin(); 4532 FieldDecl *NewFD 4533 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4534 AS, PrevDecl, &D); 4535 if (NewFD->isInvalidDecl() && PrevDecl) { 4536 // Don't introduce NewFD into scope; there's already something 4537 // with the same name in the same scope. 4538 } else if (II) { 4539 PushOnScopeChains(NewFD, S); 4540 } else 4541 Record->addDecl(NewFD); 4542 4543 return NewFD; 4544} 4545 4546/// \brief Build a new FieldDecl and check its well-formedness. 4547/// 4548/// This routine builds a new FieldDecl given the fields name, type, 4549/// record, etc. \p PrevDecl should refer to any previous declaration 4550/// with the same name and in the same scope as the field to be 4551/// created. 4552/// 4553/// \returns a new FieldDecl. 4554/// 4555/// \todo The Declarator argument is a hack. It will be removed once 4556FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4557 DeclaratorInfo *DInfo, 4558 RecordDecl *Record, SourceLocation Loc, 4559 bool Mutable, Expr *BitWidth, 4560 SourceLocation TSSL, 4561 AccessSpecifier AS, NamedDecl *PrevDecl, 4562 Declarator *D) { 4563 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4564 bool InvalidDecl = false; 4565 if (D) InvalidDecl = D->isInvalidType(); 4566 4567 // If we receive a broken type, recover by assuming 'int' and 4568 // marking this declaration as invalid. 4569 if (T.isNull()) { 4570 InvalidDecl = true; 4571 T = Context.IntTy; 4572 } 4573 4574 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4575 // than a variably modified type. 4576 if (T->isVariablyModifiedType()) { 4577 bool SizeIsNegative; 4578 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4579 SizeIsNegative); 4580 if (!FixedTy.isNull()) { 4581 Diag(Loc, diag::warn_illegal_constant_array_size); 4582 T = FixedTy; 4583 } else { 4584 if (SizeIsNegative) 4585 Diag(Loc, diag::err_typecheck_negative_array_size); 4586 else 4587 Diag(Loc, diag::err_typecheck_field_variable_size); 4588 InvalidDecl = true; 4589 } 4590 } 4591 4592 // Fields can not have abstract class types 4593 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4594 AbstractFieldType)) 4595 InvalidDecl = true; 4596 4597 bool ZeroWidth = false; 4598 // If this is declared as a bit-field, check the bit-field. 4599 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4600 InvalidDecl = true; 4601 DeleteExpr(BitWidth); 4602 BitWidth = 0; 4603 ZeroWidth = false; 4604 } 4605 4606 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4607 BitWidth, Mutable); 4608 if (InvalidDecl) 4609 NewFD->setInvalidDecl(); 4610 4611 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4612 Diag(Loc, diag::err_duplicate_member) << II; 4613 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4614 NewFD->setInvalidDecl(); 4615 } 4616 4617 if (getLangOptions().CPlusPlus) { 4618 QualType EltTy = Context.getBaseElementType(T); 4619 4620 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4621 4622 if (!T->isPODType()) 4623 CXXRecord->setPOD(false); 4624 if (!ZeroWidth) 4625 CXXRecord->setEmpty(false); 4626 4627 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4628 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4629 4630 if (!RDecl->hasTrivialConstructor()) 4631 CXXRecord->setHasTrivialConstructor(false); 4632 if (!RDecl->hasTrivialCopyConstructor()) 4633 CXXRecord->setHasTrivialCopyConstructor(false); 4634 if (!RDecl->hasTrivialCopyAssignment()) 4635 CXXRecord->setHasTrivialCopyAssignment(false); 4636 if (!RDecl->hasTrivialDestructor()) 4637 CXXRecord->setHasTrivialDestructor(false); 4638 4639 // C++ 9.5p1: An object of a class with a non-trivial 4640 // constructor, a non-trivial copy constructor, a non-trivial 4641 // destructor, or a non-trivial copy assignment operator 4642 // cannot be a member of a union, nor can an array of such 4643 // objects. 4644 // TODO: C++0x alters this restriction significantly. 4645 if (Record->isUnion()) { 4646 // We check for copy constructors before constructors 4647 // because otherwise we'll never get complaints about 4648 // copy constructors. 4649 4650 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4651 4652 CXXSpecialMember member; 4653 if (!RDecl->hasTrivialCopyConstructor()) 4654 member = CXXCopyConstructor; 4655 else if (!RDecl->hasTrivialConstructor()) 4656 member = CXXDefaultConstructor; 4657 else if (!RDecl->hasTrivialCopyAssignment()) 4658 member = CXXCopyAssignment; 4659 else if (!RDecl->hasTrivialDestructor()) 4660 member = CXXDestructor; 4661 else 4662 member = invalid; 4663 4664 if (member != invalid) { 4665 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4666 DiagnoseNontrivial(RT, member); 4667 NewFD->setInvalidDecl(); 4668 } 4669 } 4670 } 4671 } 4672 4673 // FIXME: We need to pass in the attributes given an AST 4674 // representation, not a parser representation. 4675 if (D) 4676 // FIXME: What to pass instead of TUScope? 4677 ProcessDeclAttributes(TUScope, NewFD, *D); 4678 4679 if (T.isObjCGCWeak()) 4680 Diag(Loc, diag::warn_attribute_weak_on_field); 4681 4682 NewFD->setAccess(AS); 4683 4684 // C++ [dcl.init.aggr]p1: 4685 // An aggregate is an array or a class (clause 9) with [...] no 4686 // private or protected non-static data members (clause 11). 4687 // A POD must be an aggregate. 4688 if (getLangOptions().CPlusPlus && 4689 (AS == AS_private || AS == AS_protected)) { 4690 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4691 CXXRecord->setAggregate(false); 4692 CXXRecord->setPOD(false); 4693 } 4694 4695 return NewFD; 4696} 4697 4698/// DiagnoseNontrivial - Given that a class has a non-trivial 4699/// special member, figure out why. 4700void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4701 QualType QT(T, 0U); 4702 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4703 4704 // Check whether the member was user-declared. 4705 switch (member) { 4706 case CXXDefaultConstructor: 4707 if (RD->hasUserDeclaredConstructor()) { 4708 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4709 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4710 if (!ci->isImplicitlyDefined(Context)) { 4711 SourceLocation CtorLoc = ci->getLocation(); 4712 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4713 return; 4714 } 4715 4716 assert(0 && "found no user-declared constructors"); 4717 return; 4718 } 4719 break; 4720 4721 case CXXCopyConstructor: 4722 if (RD->hasUserDeclaredCopyConstructor()) { 4723 SourceLocation CtorLoc = 4724 RD->getCopyConstructor(Context, 0)->getLocation(); 4725 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4726 return; 4727 } 4728 break; 4729 4730 case CXXCopyAssignment: 4731 if (RD->hasUserDeclaredCopyAssignment()) { 4732 // FIXME: this should use the location of the copy 4733 // assignment, not the type. 4734 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4735 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4736 return; 4737 } 4738 break; 4739 4740 case CXXDestructor: 4741 if (RD->hasUserDeclaredDestructor()) { 4742 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4743 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4744 return; 4745 } 4746 break; 4747 } 4748 4749 typedef CXXRecordDecl::base_class_iterator base_iter; 4750 4751 // Virtual bases and members inhibit trivial copying/construction, 4752 // but not trivial destruction. 4753 if (member != CXXDestructor) { 4754 // Check for virtual bases. vbases includes indirect virtual bases, 4755 // so we just iterate through the direct bases. 4756 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4757 if (bi->isVirtual()) { 4758 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4759 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4760 return; 4761 } 4762 4763 // Check for virtual methods. 4764 typedef CXXRecordDecl::method_iterator meth_iter; 4765 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4766 ++mi) { 4767 if (mi->isVirtual()) { 4768 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4769 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4770 return; 4771 } 4772 } 4773 } 4774 4775 bool (CXXRecordDecl::*hasTrivial)() const; 4776 switch (member) { 4777 case CXXDefaultConstructor: 4778 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4779 case CXXCopyConstructor: 4780 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4781 case CXXCopyAssignment: 4782 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4783 case CXXDestructor: 4784 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4785 default: 4786 assert(0 && "unexpected special member"); return; 4787 } 4788 4789 // Check for nontrivial bases (and recurse). 4790 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4791 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4792 assert(BaseRT); 4793 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4794 if (!(BaseRecTy->*hasTrivial)()) { 4795 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4796 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4797 DiagnoseNontrivial(BaseRT, member); 4798 return; 4799 } 4800 } 4801 4802 // Check for nontrivial members (and recurse). 4803 typedef RecordDecl::field_iterator field_iter; 4804 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4805 ++fi) { 4806 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4807 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4808 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4809 4810 if (!(EltRD->*hasTrivial)()) { 4811 SourceLocation FLoc = (*fi)->getLocation(); 4812 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4813 DiagnoseNontrivial(EltRT, member); 4814 return; 4815 } 4816 } 4817 } 4818 4819 assert(0 && "found no explanation for non-trivial member"); 4820} 4821 4822/// TranslateIvarVisibility - Translate visibility from a token ID to an 4823/// AST enum value. 4824static ObjCIvarDecl::AccessControl 4825TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4826 switch (ivarVisibility) { 4827 default: assert(0 && "Unknown visitibility kind"); 4828 case tok::objc_private: return ObjCIvarDecl::Private; 4829 case tok::objc_public: return ObjCIvarDecl::Public; 4830 case tok::objc_protected: return ObjCIvarDecl::Protected; 4831 case tok::objc_package: return ObjCIvarDecl::Package; 4832 } 4833} 4834 4835/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4836/// in order to create an IvarDecl object for it. 4837Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4838 SourceLocation DeclStart, 4839 DeclPtrTy IntfDecl, 4840 Declarator &D, ExprTy *BitfieldWidth, 4841 tok::ObjCKeywordKind Visibility) { 4842 4843 IdentifierInfo *II = D.getIdentifier(); 4844 Expr *BitWidth = (Expr*)BitfieldWidth; 4845 SourceLocation Loc = DeclStart; 4846 if (II) Loc = D.getIdentifierLoc(); 4847 4848 // FIXME: Unnamed fields can be handled in various different ways, for 4849 // example, unnamed unions inject all members into the struct namespace! 4850 4851 DeclaratorInfo *DInfo = 0; 4852 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4853 4854 if (BitWidth) { 4855 // 6.7.2.1p3, 6.7.2.1p4 4856 if (VerifyBitField(Loc, II, T, BitWidth)) { 4857 D.setInvalidType(); 4858 DeleteExpr(BitWidth); 4859 BitWidth = 0; 4860 } 4861 } else { 4862 // Not a bitfield. 4863 4864 // validate II. 4865 4866 } 4867 4868 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4869 // than a variably modified type. 4870 if (T->isVariablyModifiedType()) { 4871 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4872 D.setInvalidType(); 4873 } 4874 4875 // Get the visibility (access control) for this ivar. 4876 ObjCIvarDecl::AccessControl ac = 4877 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4878 : ObjCIvarDecl::None; 4879 // Must set ivar's DeclContext to its enclosing interface. 4880 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4881 DeclContext *EnclosingContext; 4882 if (ObjCImplementationDecl *IMPDecl = 4883 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4884 // Case of ivar declared in an implementation. Context is that of its class. 4885 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4886 assert(IDecl && "No class- ActOnIvar"); 4887 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4888 } else 4889 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4890 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4891 4892 // Construct the decl. 4893 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4894 EnclosingContext, Loc, II, T, 4895 DInfo, ac, (Expr *)BitfieldWidth); 4896 4897 if (II) { 4898 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4899 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4900 && !isa<TagDecl>(PrevDecl)) { 4901 Diag(Loc, diag::err_duplicate_member) << II; 4902 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4903 NewID->setInvalidDecl(); 4904 } 4905 } 4906 4907 // Process attributes attached to the ivar. 4908 ProcessDeclAttributes(S, NewID, D); 4909 4910 if (D.isInvalidType()) 4911 NewID->setInvalidDecl(); 4912 4913 if (II) { 4914 // FIXME: When interfaces are DeclContexts, we'll need to add 4915 // these to the interface. 4916 S->AddDecl(DeclPtrTy::make(NewID)); 4917 IdResolver.AddDecl(NewID); 4918 } 4919 4920 return DeclPtrTy::make(NewID); 4921} 4922 4923void Sema::ActOnFields(Scope* S, 4924 SourceLocation RecLoc, DeclPtrTy RecDecl, 4925 DeclPtrTy *Fields, unsigned NumFields, 4926 SourceLocation LBrac, SourceLocation RBrac, 4927 AttributeList *Attr) { 4928 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4929 assert(EnclosingDecl && "missing record or interface decl"); 4930 4931 // If the decl this is being inserted into is invalid, then it may be a 4932 // redeclaration or some other bogus case. Don't try to add fields to it. 4933 if (EnclosingDecl->isInvalidDecl()) { 4934 // FIXME: Deallocate fields? 4935 return; 4936 } 4937 4938 4939 // Verify that all the fields are okay. 4940 unsigned NumNamedMembers = 0; 4941 llvm::SmallVector<FieldDecl*, 32> RecFields; 4942 4943 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4944 for (unsigned i = 0; i != NumFields; ++i) { 4945 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4946 4947 // Get the type for the field. 4948 Type *FDTy = FD->getType().getTypePtr(); 4949 4950 if (!FD->isAnonymousStructOrUnion()) { 4951 // Remember all fields written by the user. 4952 RecFields.push_back(FD); 4953 } 4954 4955 // If the field is already invalid for some reason, don't emit more 4956 // diagnostics about it. 4957 if (FD->isInvalidDecl()) 4958 continue; 4959 4960 // C99 6.7.2.1p2: 4961 // A structure or union shall not contain a member with 4962 // incomplete or function type (hence, a structure shall not 4963 // contain an instance of itself, but may contain a pointer to 4964 // an instance of itself), except that the last member of a 4965 // structure with more than one named member may have incomplete 4966 // array type; such a structure (and any union containing, 4967 // possibly recursively, a member that is such a structure) 4968 // shall not be a member of a structure or an element of an 4969 // array. 4970 if (FDTy->isFunctionType()) { 4971 // Field declared as a function. 4972 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4973 << FD->getDeclName(); 4974 FD->setInvalidDecl(); 4975 EnclosingDecl->setInvalidDecl(); 4976 continue; 4977 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4978 Record && Record->isStruct()) { 4979 // Flexible array member. 4980 if (NumNamedMembers < 1) { 4981 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4982 << FD->getDeclName(); 4983 FD->setInvalidDecl(); 4984 EnclosingDecl->setInvalidDecl(); 4985 continue; 4986 } 4987 // Okay, we have a legal flexible array member at the end of the struct. 4988 if (Record) 4989 Record->setHasFlexibleArrayMember(true); 4990 } else if (!FDTy->isDependentType() && 4991 RequireCompleteType(FD->getLocation(), FD->getType(), 4992 diag::err_field_incomplete)) { 4993 // Incomplete type 4994 FD->setInvalidDecl(); 4995 EnclosingDecl->setInvalidDecl(); 4996 continue; 4997 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 4998 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4999 // If this is a member of a union, then entire union becomes "flexible". 5000 if (Record && Record->isUnion()) { 5001 Record->setHasFlexibleArrayMember(true); 5002 } else { 5003 // If this is a struct/class and this is not the last element, reject 5004 // it. Note that GCC supports variable sized arrays in the middle of 5005 // structures. 5006 if (i != NumFields-1) 5007 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5008 << FD->getDeclName() << FD->getType(); 5009 else { 5010 // We support flexible arrays at the end of structs in 5011 // other structs as an extension. 5012 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5013 << FD->getDeclName(); 5014 if (Record) 5015 Record->setHasFlexibleArrayMember(true); 5016 } 5017 } 5018 } 5019 if (Record && FDTTy->getDecl()->hasObjectMember()) 5020 Record->setHasObjectMember(true); 5021 } else if (FDTy->isObjCInterfaceType()) { 5022 /// A field cannot be an Objective-c object 5023 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5024 FD->setInvalidDecl(); 5025 EnclosingDecl->setInvalidDecl(); 5026 continue; 5027 } else if (getLangOptions().ObjC1 && 5028 getLangOptions().getGCMode() != LangOptions::NonGC && 5029 Record && 5030 (FD->getType()->isObjCObjectPointerType() || 5031 FD->getType().isObjCGCStrong())) 5032 Record->setHasObjectMember(true); 5033 // Keep track of the number of named members. 5034 if (FD->getIdentifier()) 5035 ++NumNamedMembers; 5036 } 5037 5038 // Okay, we successfully defined 'Record'. 5039 if (Record) { 5040 Record->completeDefinition(Context); 5041 } else { 5042 ObjCIvarDecl **ClsFields = 5043 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5044 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5045 ID->setIVarList(ClsFields, RecFields.size(), Context); 5046 ID->setLocEnd(RBrac); 5047 // Add ivar's to class's DeclContext. 5048 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5049 ClsFields[i]->setLexicalDeclContext(ID); 5050 ID->addDecl(ClsFields[i]); 5051 } 5052 // Must enforce the rule that ivars in the base classes may not be 5053 // duplicates. 5054 if (ID->getSuperClass()) { 5055 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5056 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5057 ObjCIvarDecl* Ivar = (*IVI); 5058 5059 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5060 ObjCIvarDecl* prevIvar = 5061 ID->getSuperClass()->lookupInstanceVariable(II); 5062 if (prevIvar) { 5063 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5064 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5065 } 5066 } 5067 } 5068 } 5069 } else if (ObjCImplementationDecl *IMPDecl = 5070 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5071 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5072 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5073 // Ivar declared in @implementation never belongs to the implementation. 5074 // Only it is in implementation's lexical context. 5075 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5076 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5077 } 5078 } 5079 5080 if (Attr) 5081 ProcessDeclAttributeList(S, Record, Attr); 5082} 5083 5084EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5085 EnumConstantDecl *LastEnumConst, 5086 SourceLocation IdLoc, 5087 IdentifierInfo *Id, 5088 ExprArg val) { 5089 Expr *Val = (Expr *)val.get(); 5090 5091 llvm::APSInt EnumVal(32); 5092 QualType EltTy; 5093 if (Val && !Val->isTypeDependent()) { 5094 // Make sure to promote the operand type to int. 5095 UsualUnaryConversions(Val); 5096 if (Val != val.get()) { 5097 val.release(); 5098 val = Val; 5099 } 5100 5101 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5102 SourceLocation ExpLoc; 5103 if (!Val->isValueDependent() && 5104 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5105 Val = 0; 5106 } else { 5107 EltTy = Val->getType(); 5108 } 5109 } 5110 5111 if (!Val) { 5112 if (LastEnumConst) { 5113 // Assign the last value + 1. 5114 EnumVal = LastEnumConst->getInitVal(); 5115 ++EnumVal; 5116 5117 // Check for overflow on increment. 5118 if (EnumVal < LastEnumConst->getInitVal()) 5119 Diag(IdLoc, diag::warn_enum_value_overflow); 5120 5121 EltTy = LastEnumConst->getType(); 5122 } else { 5123 // First value, set to zero. 5124 EltTy = Context.IntTy; 5125 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5126 } 5127 } 5128 5129 val.release(); 5130 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5131 Val, EnumVal); 5132} 5133 5134 5135Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5136 DeclPtrTy lastEnumConst, 5137 SourceLocation IdLoc, 5138 IdentifierInfo *Id, 5139 SourceLocation EqualLoc, ExprTy *val) { 5140 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5141 EnumConstantDecl *LastEnumConst = 5142 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5143 Expr *Val = static_cast<Expr*>(val); 5144 5145 // The scope passed in may not be a decl scope. Zip up the scope tree until 5146 // we find one that is. 5147 S = getNonFieldDeclScope(S); 5148 5149 // Verify that there isn't already something declared with this name in this 5150 // scope. 5151 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5152 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5153 // Maybe we will complain about the shadowed template parameter. 5154 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5155 // Just pretend that we didn't see the previous declaration. 5156 PrevDecl = 0; 5157 } 5158 5159 if (PrevDecl) { 5160 // When in C++, we may get a TagDecl with the same name; in this case the 5161 // enum constant will 'hide' the tag. 5162 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5163 "Received TagDecl when not in C++!"); 5164 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5165 if (isa<EnumConstantDecl>(PrevDecl)) 5166 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5167 else 5168 Diag(IdLoc, diag::err_redefinition) << Id; 5169 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5170 if (Val) Val->Destroy(Context); 5171 return DeclPtrTy(); 5172 } 5173 } 5174 5175 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5176 IdLoc, Id, Owned(Val)); 5177 5178 // Register this decl in the current scope stack. 5179 if (New) 5180 PushOnScopeChains(New, S); 5181 5182 return DeclPtrTy::make(New); 5183} 5184 5185void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5186 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5187 DeclPtrTy *Elements, unsigned NumElements, 5188 Scope *S, AttributeList *Attr) { 5189 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5190 QualType EnumType = Context.getTypeDeclType(Enum); 5191 5192 if (Attr) 5193 ProcessDeclAttributeList(S, Enum, Attr); 5194 5195 // TODO: If the result value doesn't fit in an int, it must be a long or long 5196 // long value. ISO C does not support this, but GCC does as an extension, 5197 // emit a warning. 5198 unsigned IntWidth = Context.Target.getIntWidth(); 5199 unsigned CharWidth = Context.Target.getCharWidth(); 5200 unsigned ShortWidth = Context.Target.getShortWidth(); 5201 5202 // Verify that all the values are okay, compute the size of the values, and 5203 // reverse the list. 5204 unsigned NumNegativeBits = 0; 5205 unsigned NumPositiveBits = 0; 5206 5207 // Keep track of whether all elements have type int. 5208 bool AllElementsInt = true; 5209 5210 for (unsigned i = 0; i != NumElements; ++i) { 5211 EnumConstantDecl *ECD = 5212 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5213 if (!ECD) continue; // Already issued a diagnostic. 5214 5215 // If the enum value doesn't fit in an int, emit an extension warning. 5216 const llvm::APSInt &InitVal = ECD->getInitVal(); 5217 assert(InitVal.getBitWidth() >= IntWidth && 5218 "Should have promoted value to int"); 5219 if (InitVal.getBitWidth() > IntWidth) { 5220 llvm::APSInt V(InitVal); 5221 V.trunc(IntWidth); 5222 V.extend(InitVal.getBitWidth()); 5223 if (V != InitVal) 5224 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5225 << InitVal.toString(10); 5226 } 5227 5228 // Keep track of the size of positive and negative values. 5229 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5230 NumPositiveBits = std::max(NumPositiveBits, 5231 (unsigned)InitVal.getActiveBits()); 5232 else 5233 NumNegativeBits = std::max(NumNegativeBits, 5234 (unsigned)InitVal.getMinSignedBits()); 5235 5236 // Keep track of whether every enum element has type int (very commmon). 5237 if (AllElementsInt) 5238 AllElementsInt = ECD->getType() == Context.IntTy; 5239 } 5240 5241 // Figure out the type that should be used for this enum. 5242 // FIXME: Support -fshort-enums. 5243 QualType BestType; 5244 unsigned BestWidth; 5245 5246 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5247 5248 if (NumNegativeBits) { 5249 // If there is a negative value, figure out the smallest integer type (of 5250 // int/long/longlong) that fits. 5251 // If it's packed, check also if it fits a char or a short. 5252 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5253 BestType = Context.SignedCharTy; 5254 BestWidth = CharWidth; 5255 } else if (Packed && NumNegativeBits <= ShortWidth && 5256 NumPositiveBits < ShortWidth) { 5257 BestType = Context.ShortTy; 5258 BestWidth = ShortWidth; 5259 } 5260 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5261 BestType = Context.IntTy; 5262 BestWidth = IntWidth; 5263 } else { 5264 BestWidth = Context.Target.getLongWidth(); 5265 5266 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5267 BestType = Context.LongTy; 5268 else { 5269 BestWidth = Context.Target.getLongLongWidth(); 5270 5271 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5272 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5273 BestType = Context.LongLongTy; 5274 } 5275 } 5276 } else { 5277 // If there is no negative value, figure out which of uint, ulong, ulonglong 5278 // fits. 5279 // If it's packed, check also if it fits a char or a short. 5280 if (Packed && NumPositiveBits <= CharWidth) { 5281 BestType = Context.UnsignedCharTy; 5282 BestWidth = CharWidth; 5283 } else if (Packed && NumPositiveBits <= ShortWidth) { 5284 BestType = Context.UnsignedShortTy; 5285 BestWidth = ShortWidth; 5286 } 5287 else if (NumPositiveBits <= IntWidth) { 5288 BestType = Context.UnsignedIntTy; 5289 BestWidth = IntWidth; 5290 } else if (NumPositiveBits <= 5291 (BestWidth = Context.Target.getLongWidth())) { 5292 BestType = Context.UnsignedLongTy; 5293 } else { 5294 BestWidth = Context.Target.getLongLongWidth(); 5295 assert(NumPositiveBits <= BestWidth && 5296 "How could an initializer get larger than ULL?"); 5297 BestType = Context.UnsignedLongLongTy; 5298 } 5299 } 5300 5301 // Loop over all of the enumerator constants, changing their types to match 5302 // the type of the enum if needed. 5303 for (unsigned i = 0; i != NumElements; ++i) { 5304 EnumConstantDecl *ECD = 5305 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5306 if (!ECD) continue; // Already issued a diagnostic. 5307 5308 // Standard C says the enumerators have int type, but we allow, as an 5309 // extension, the enumerators to be larger than int size. If each 5310 // enumerator value fits in an int, type it as an int, otherwise type it the 5311 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5312 // that X has type 'int', not 'unsigned'. 5313 if (ECD->getType() == Context.IntTy) { 5314 // Make sure the init value is signed. 5315 llvm::APSInt IV = ECD->getInitVal(); 5316 IV.setIsSigned(true); 5317 ECD->setInitVal(IV); 5318 5319 if (getLangOptions().CPlusPlus) 5320 // C++ [dcl.enum]p4: Following the closing brace of an 5321 // enum-specifier, each enumerator has the type of its 5322 // enumeration. 5323 ECD->setType(EnumType); 5324 continue; // Already int type. 5325 } 5326 5327 // Determine whether the value fits into an int. 5328 llvm::APSInt InitVal = ECD->getInitVal(); 5329 bool FitsInInt; 5330 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5331 FitsInInt = InitVal.getActiveBits() < IntWidth; 5332 else 5333 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5334 5335 // If it fits into an integer type, force it. Otherwise force it to match 5336 // the enum decl type. 5337 QualType NewTy; 5338 unsigned NewWidth; 5339 bool NewSign; 5340 if (FitsInInt) { 5341 NewTy = Context.IntTy; 5342 NewWidth = IntWidth; 5343 NewSign = true; 5344 } else if (ECD->getType() == BestType) { 5345 // Already the right type! 5346 if (getLangOptions().CPlusPlus) 5347 // C++ [dcl.enum]p4: Following the closing brace of an 5348 // enum-specifier, each enumerator has the type of its 5349 // enumeration. 5350 ECD->setType(EnumType); 5351 continue; 5352 } else { 5353 NewTy = BestType; 5354 NewWidth = BestWidth; 5355 NewSign = BestType->isSignedIntegerType(); 5356 } 5357 5358 // Adjust the APSInt value. 5359 InitVal.extOrTrunc(NewWidth); 5360 InitVal.setIsSigned(NewSign); 5361 ECD->setInitVal(InitVal); 5362 5363 // Adjust the Expr initializer and type. 5364 if (ECD->getInitExpr()) 5365 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5366 CastExpr::CK_Unknown, 5367 ECD->getInitExpr(), 5368 /*isLvalue=*/false)); 5369 if (getLangOptions().CPlusPlus) 5370 // C++ [dcl.enum]p4: Following the closing brace of an 5371 // enum-specifier, each enumerator has the type of its 5372 // enumeration. 5373 ECD->setType(EnumType); 5374 else 5375 ECD->setType(NewTy); 5376 } 5377 5378 Enum->completeDefinition(Context, BestType); 5379} 5380 5381Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5382 ExprArg expr) { 5383 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5384 5385 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5386 Loc, AsmString); 5387 CurContext->addDecl(New); 5388 return DeclPtrTy::make(New); 5389} 5390 5391void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5392 SourceLocation PragmaLoc, 5393 SourceLocation NameLoc) { 5394 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5395 5396 if (PrevDecl) { 5397 PrevDecl->addAttr(::new (Context) WeakAttr()); 5398 } else { 5399 (void)WeakUndeclaredIdentifiers.insert( 5400 std::pair<IdentifierInfo*,WeakInfo> 5401 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5402 } 5403} 5404 5405void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5406 IdentifierInfo* AliasName, 5407 SourceLocation PragmaLoc, 5408 SourceLocation NameLoc, 5409 SourceLocation AliasNameLoc) { 5410 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5411 WeakInfo W = WeakInfo(Name, NameLoc); 5412 5413 if (PrevDecl) { 5414 if (!PrevDecl->hasAttr<AliasAttr>()) 5415 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5416 DeclApplyPragmaWeak(TUScope, ND, W); 5417 } else { 5418 (void)WeakUndeclaredIdentifiers.insert( 5419 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5420 } 5421} 5422