SemaDecl.cpp revision db422dffb720ff41d0b60e228f45c685600ffa9e
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/Analysis/CFG.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Basic/PartialDiagnostic.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/Basic/TargetInfo.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/BitVector.h" 33#include "llvm/ADT/STLExtras.h" 34#include <algorithm> 35#include <functional> 36#include <queue> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, const CXXScopeSpec *SS, 65 bool isClassName) { 66 // C++ [temp.res]p3: 67 // A qualified-id that refers to a type and in which the 68 // nested-name-specifier depends on a template-parameter (14.6.2) 69 // shall be prefixed by the keyword typename to indicate that the 70 // qualified-id denotes a type, forming an 71 // elaborated-type-specifier (7.1.5.3). 72 // 73 // We therefore do not perform any name lookup if the result would 74 // refer to a member of an unknown specialization. 75 if (SS && isUnknownSpecialization(*SS)) { 76 if (!isClassName) 77 return 0; 78 79 // We know from the grammar that this name refers to a type, so build a 80 // TypenameType node to describe the type. 81 // FIXME: Record somewhere that this TypenameType node has no "typename" 82 // keyword associated with it. 83 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 84 II, SS->getRange()).getAsOpaquePtr(); 85 } 86 87 LookupResult Result 88 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 89 90 NamedDecl *IIDecl = 0; 91 switch (Result.getKind()) { 92 case LookupResult::NotFound: 93 case LookupResult::FoundOverloaded: 94 return 0; 95 96 case LookupResult::AmbiguousBaseSubobjectTypes: 97 case LookupResult::AmbiguousBaseSubobjects: 98 case LookupResult::AmbiguousReference: { 99 // Look to see if we have a type anywhere in the list of results. 100 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 101 Res != ResEnd; ++Res) { 102 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 103 if (!IIDecl || 104 (*Res)->getLocation().getRawEncoding() < 105 IIDecl->getLocation().getRawEncoding()) 106 IIDecl = *Res; 107 } 108 } 109 110 if (!IIDecl) { 111 // None of the entities we found is a type, so there is no way 112 // to even assume that the result is a type. In this case, don't 113 // complain about the ambiguity. The parser will either try to 114 // perform this lookup again (e.g., as an object name), which 115 // will produce the ambiguity, or will complain that it expected 116 // a type name. 117 Result.Destroy(); 118 return 0; 119 } 120 121 // We found a type within the ambiguous lookup; diagnose the 122 // ambiguity and then return that type. This might be the right 123 // answer, or it might not be, but it suppresses any attempt to 124 // perform the name lookup again. 125 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 126 break; 127 } 128 129 case LookupResult::Found: 130 IIDecl = Result.getAsDecl(); 131 break; 132 } 133 134 if (IIDecl) { 135 QualType T; 136 137 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 138 // Check whether we can use this type 139 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 140 141 if (getLangOptions().CPlusPlus) { 142 // C++ [temp.local]p2: 143 // Within the scope of a class template specialization or 144 // partial specialization, when the injected-class-name is 145 // not followed by a <, it is equivalent to the 146 // injected-class-name followed by the template-argument s 147 // of the class template specialization or partial 148 // specialization enclosed in <>. 149 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 150 if (RD->isInjectedClassName()) 151 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 152 T = Template->getInjectedClassNameType(Context); 153 } 154 155 if (T.isNull()) 156 T = Context.getTypeDeclType(TD); 157 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 158 // Check whether we can use this interface. 159 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 160 161 T = Context.getObjCInterfaceType(IDecl); 162 } else 163 return 0; 164 165 if (SS) 166 T = getQualifiedNameType(*SS, T); 167 168 return T.getAsOpaquePtr(); 169 } 170 171 return 0; 172} 173 174/// isTagName() - This method is called *for error recovery purposes only* 175/// to determine if the specified name is a valid tag name ("struct foo"). If 176/// so, this returns the TST for the tag corresponding to it (TST_enum, 177/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 178/// where the user forgot to specify the tag. 179DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 180 // Do a tag name lookup in this scope. 181 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 182 if (R.getKind() == LookupResult::Found) 183 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 184 switch (TD->getTagKind()) { 185 case TagDecl::TK_struct: return DeclSpec::TST_struct; 186 case TagDecl::TK_union: return DeclSpec::TST_union; 187 case TagDecl::TK_class: return DeclSpec::TST_class; 188 case TagDecl::TK_enum: return DeclSpec::TST_enum; 189 } 190 } 191 192 return DeclSpec::TST_unspecified; 193} 194 195 196// Determines the context to return to after temporarily entering a 197// context. This depends in an unnecessarily complicated way on the 198// exact ordering of callbacks from the parser. 199DeclContext *Sema::getContainingDC(DeclContext *DC) { 200 201 // Functions defined inline within classes aren't parsed until we've 202 // finished parsing the top-level class, so the top-level class is 203 // the context we'll need to return to. 204 if (isa<FunctionDecl>(DC)) { 205 DC = DC->getLexicalParent(); 206 207 // A function not defined within a class will always return to its 208 // lexical context. 209 if (!isa<CXXRecordDecl>(DC)) 210 return DC; 211 212 // A C++ inline method/friend is parsed *after* the topmost class 213 // it was declared in is fully parsed ("complete"); the topmost 214 // class is the context we need to return to. 215 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 216 DC = RD; 217 218 // Return the declaration context of the topmost class the inline method is 219 // declared in. 220 return DC; 221 } 222 223 if (isa<ObjCMethodDecl>(DC)) 224 return Context.getTranslationUnitDecl(); 225 226 return DC->getLexicalParent(); 227} 228 229void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 230 assert(getContainingDC(DC) == CurContext && 231 "The next DeclContext should be lexically contained in the current one."); 232 CurContext = DC; 233 S->setEntity(DC); 234} 235 236void Sema::PopDeclContext() { 237 assert(CurContext && "DeclContext imbalance!"); 238 239 CurContext = getContainingDC(CurContext); 240} 241 242/// EnterDeclaratorContext - Used when we must lookup names in the context 243/// of a declarator's nested name specifier. 244void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 245 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 246 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 247 CurContext = DC; 248 assert(CurContext && "No context?"); 249 S->setEntity(CurContext); 250} 251 252void Sema::ExitDeclaratorContext(Scope *S) { 253 S->setEntity(PreDeclaratorDC); 254 PreDeclaratorDC = 0; 255 256 // Reset CurContext to the nearest enclosing context. 257 while (!S->getEntity() && S->getParent()) 258 S = S->getParent(); 259 CurContext = static_cast<DeclContext*>(S->getEntity()); 260 assert(CurContext && "No context?"); 261} 262 263/// \brief Determine whether we allow overloading of the function 264/// PrevDecl with another declaration. 265/// 266/// This routine determines whether overloading is possible, not 267/// whether some new function is actually an overload. It will return 268/// true in C++ (where we can always provide overloads) or, as an 269/// extension, in C when the previous function is already an 270/// overloaded function declaration or has the "overloadable" 271/// attribute. 272static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 273 if (Context.getLangOptions().CPlusPlus) 274 return true; 275 276 if (isa<OverloadedFunctionDecl>(PrevDecl)) 277 return true; 278 279 return PrevDecl->getAttr<OverloadableAttr>() != 0; 280} 281 282/// Add this decl to the scope shadowed decl chains. 283void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 284 // Move up the scope chain until we find the nearest enclosing 285 // non-transparent context. The declaration will be introduced into this 286 // scope. 287 while (S->getEntity() && 288 ((DeclContext *)S->getEntity())->isTransparentContext()) 289 S = S->getParent(); 290 291 S->AddDecl(DeclPtrTy::make(D)); 292 293 // Add scoped declarations into their context, so that they can be 294 // found later. Declarations without a context won't be inserted 295 // into any context. 296 if (AddToContext) 297 CurContext->addDecl(D); 298 299 // C++ [basic.scope]p4: 300 // -- exactly one declaration shall declare a class name or 301 // enumeration name that is not a typedef name and the other 302 // declarations shall all refer to the same object or 303 // enumerator, or all refer to functions and function templates; 304 // in this case the class name or enumeration name is hidden. 305 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 306 // We are pushing the name of a tag (enum or class). 307 if (CurContext->getLookupContext() 308 == TD->getDeclContext()->getLookupContext()) { 309 // We're pushing the tag into the current context, which might 310 // require some reshuffling in the identifier resolver. 311 IdentifierResolver::iterator 312 I = IdResolver.begin(TD->getDeclName()), 313 IEnd = IdResolver.end(); 314 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 315 NamedDecl *PrevDecl = *I; 316 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 317 PrevDecl = *I, ++I) { 318 if (TD->declarationReplaces(*I)) { 319 // This is a redeclaration. Remove it from the chain and 320 // break out, so that we'll add in the shadowed 321 // declaration. 322 S->RemoveDecl(DeclPtrTy::make(*I)); 323 if (PrevDecl == *I) { 324 IdResolver.RemoveDecl(*I); 325 IdResolver.AddDecl(TD); 326 return; 327 } else { 328 IdResolver.RemoveDecl(*I); 329 break; 330 } 331 } 332 } 333 334 // There is already a declaration with the same name in the same 335 // scope, which is not a tag declaration. It must be found 336 // before we find the new declaration, so insert the new 337 // declaration at the end of the chain. 338 IdResolver.AddShadowedDecl(TD, PrevDecl); 339 340 return; 341 } 342 } 343 } else if ((isa<FunctionDecl>(D) && 344 AllowOverloadingOfFunction(D, Context)) || 345 isa<FunctionTemplateDecl>(D)) { 346 // We are pushing the name of a function or function template, 347 // which might be an overloaded name. 348 IdentifierResolver::iterator Redecl 349 = std::find_if(IdResolver.begin(D->getDeclName()), 350 IdResolver.end(), 351 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 352 D)); 353 if (Redecl != IdResolver.end() && 354 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 355 // There is already a declaration of a function on our 356 // IdResolver chain. Replace it with this declaration. 357 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 358 IdResolver.RemoveDecl(*Redecl); 359 } 360 } else if (isa<ObjCInterfaceDecl>(D)) { 361 // We're pushing an Objective-C interface into the current 362 // context. If there is already an alias declaration, remove it first. 363 for (IdentifierResolver::iterator 364 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 365 I != IEnd; ++I) { 366 if (isa<ObjCCompatibleAliasDecl>(*I)) { 367 S->RemoveDecl(DeclPtrTy::make(*I)); 368 IdResolver.RemoveDecl(*I); 369 break; 370 } 371 } 372 } 373 374 IdResolver.AddDecl(D); 375} 376 377void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 378 if (S->decl_empty()) return; 379 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 380 "Scope shouldn't contain decls!"); 381 382 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 383 I != E; ++I) { 384 Decl *TmpD = (*I).getAs<Decl>(); 385 assert(TmpD && "This decl didn't get pushed??"); 386 387 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 388 NamedDecl *D = cast<NamedDecl>(TmpD); 389 390 if (!D->getDeclName()) continue; 391 392 // Remove this name from our lexical scope. 393 IdResolver.RemoveDecl(D); 394 } 395} 396 397/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 398/// return 0 if one not found. 399ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 400 // The third "scope" argument is 0 since we aren't enabling lazy built-in 401 // creation from this context. 402 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 403 404 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 405} 406 407/// getNonFieldDeclScope - Retrieves the innermost scope, starting 408/// from S, where a non-field would be declared. This routine copes 409/// with the difference between C and C++ scoping rules in structs and 410/// unions. For example, the following code is well-formed in C but 411/// ill-formed in C++: 412/// @code 413/// struct S6 { 414/// enum { BAR } e; 415/// }; 416/// 417/// void test_S6() { 418/// struct S6 a; 419/// a.e = BAR; 420/// } 421/// @endcode 422/// For the declaration of BAR, this routine will return a different 423/// scope. The scope S will be the scope of the unnamed enumeration 424/// within S6. In C++, this routine will return the scope associated 425/// with S6, because the enumeration's scope is a transparent 426/// context but structures can contain non-field names. In C, this 427/// routine will return the translation unit scope, since the 428/// enumeration's scope is a transparent context and structures cannot 429/// contain non-field names. 430Scope *Sema::getNonFieldDeclScope(Scope *S) { 431 while (((S->getFlags() & Scope::DeclScope) == 0) || 432 (S->getEntity() && 433 ((DeclContext *)S->getEntity())->isTransparentContext()) || 434 (S->isClassScope() && !getLangOptions().CPlusPlus)) 435 S = S->getParent(); 436 return S; 437} 438 439void Sema::InitBuiltinVaListType() { 440 if (!Context.getBuiltinVaListType().isNull()) 441 return; 442 443 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 444 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 445 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 446 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 447} 448 449/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 450/// file scope. lazily create a decl for it. ForRedeclaration is true 451/// if we're creating this built-in in anticipation of redeclaring the 452/// built-in. 453NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 454 Scope *S, bool ForRedeclaration, 455 SourceLocation Loc) { 456 Builtin::ID BID = (Builtin::ID)bid; 457 458 if (Context.BuiltinInfo.hasVAListUse(BID)) 459 InitBuiltinVaListType(); 460 461 ASTContext::GetBuiltinTypeError Error; 462 QualType R = Context.GetBuiltinType(BID, Error); 463 switch (Error) { 464 case ASTContext::GE_None: 465 // Okay 466 break; 467 468 case ASTContext::GE_Missing_stdio: 469 if (ForRedeclaration) 470 Diag(Loc, diag::err_implicit_decl_requires_stdio) 471 << Context.BuiltinInfo.GetName(BID); 472 return 0; 473 474 case ASTContext::GE_Missing_setjmp: 475 if (ForRedeclaration) 476 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 477 << Context.BuiltinInfo.GetName(BID); 478 return 0; 479 } 480 481 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 482 Diag(Loc, diag::ext_implicit_lib_function_decl) 483 << Context.BuiltinInfo.GetName(BID) 484 << R; 485 if (Context.BuiltinInfo.getHeaderName(BID) && 486 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 487 != Diagnostic::Ignored) 488 Diag(Loc, diag::note_please_include_header) 489 << Context.BuiltinInfo.getHeaderName(BID) 490 << Context.BuiltinInfo.GetName(BID); 491 } 492 493 FunctionDecl *New = FunctionDecl::Create(Context, 494 Context.getTranslationUnitDecl(), 495 Loc, II, R, /*DInfo=*/0, 496 FunctionDecl::Extern, false, 497 /*hasPrototype=*/true); 498 New->setImplicit(); 499 500 // Create Decl objects for each parameter, adding them to the 501 // FunctionDecl. 502 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 503 llvm::SmallVector<ParmVarDecl*, 16> Params; 504 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 505 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 506 FT->getArgType(i), /*DInfo=*/0, 507 VarDecl::None, 0)); 508 New->setParams(Context, Params.data(), Params.size()); 509 } 510 511 AddKnownFunctionAttributes(New); 512 513 // TUScope is the translation-unit scope to insert this function into. 514 // FIXME: This is hideous. We need to teach PushOnScopeChains to 515 // relate Scopes to DeclContexts, and probably eliminate CurContext 516 // entirely, but we're not there yet. 517 DeclContext *SavedContext = CurContext; 518 CurContext = Context.getTranslationUnitDecl(); 519 PushOnScopeChains(New, TUScope); 520 CurContext = SavedContext; 521 return New; 522} 523 524/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 525/// same name and scope as a previous declaration 'Old'. Figure out 526/// how to resolve this situation, merging decls or emitting 527/// diagnostics as appropriate. If there was an error, set New to be invalid. 528/// 529void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 530 // If either decl is known invalid already, set the new one to be invalid and 531 // don't bother doing any merging checks. 532 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 533 return New->setInvalidDecl(); 534 535 // Allow multiple definitions for ObjC built-in typedefs. 536 // FIXME: Verify the underlying types are equivalent! 537 if (getLangOptions().ObjC1) { 538 const IdentifierInfo *TypeID = New->getIdentifier(); 539 switch (TypeID->getLength()) { 540 default: break; 541 case 2: 542 if (!TypeID->isStr("id")) 543 break; 544 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 545 // Install the built-in type for 'id', ignoring the current definition. 546 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 547 return; 548 case 5: 549 if (!TypeID->isStr("Class")) 550 break; 551 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 552 // Install the built-in type for 'Class', ignoring the current definition. 553 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 554 return; 555 case 3: 556 if (!TypeID->isStr("SEL")) 557 break; 558 Context.setObjCSelType(Context.getTypeDeclType(New)); 559 return; 560 case 8: 561 if (!TypeID->isStr("Protocol")) 562 break; 563 Context.setObjCProtoType(New->getUnderlyingType()); 564 return; 565 } 566 // Fall through - the typedef name was not a builtin type. 567 } 568 // Verify the old decl was also a type. 569 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 570 if (!Old) { 571 Diag(New->getLocation(), diag::err_redefinition_different_kind) 572 << New->getDeclName(); 573 if (OldD->getLocation().isValid()) 574 Diag(OldD->getLocation(), diag::note_previous_definition); 575 return New->setInvalidDecl(); 576 } 577 578 // Determine the "old" type we'll use for checking and diagnostics. 579 QualType OldType; 580 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 581 OldType = OldTypedef->getUnderlyingType(); 582 else 583 OldType = Context.getTypeDeclType(Old); 584 585 // If the typedef types are not identical, reject them in all languages and 586 // with any extensions enabled. 587 588 if (OldType != New->getUnderlyingType() && 589 Context.getCanonicalType(OldType) != 590 Context.getCanonicalType(New->getUnderlyingType())) { 591 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 592 << New->getUnderlyingType() << OldType; 593 if (Old->getLocation().isValid()) 594 Diag(Old->getLocation(), diag::note_previous_definition); 595 return New->setInvalidDecl(); 596 } 597 598 if (getLangOptions().Microsoft) 599 return; 600 601 // C++ [dcl.typedef]p2: 602 // In a given non-class scope, a typedef specifier can be used to 603 // redefine the name of any type declared in that scope to refer 604 // to the type to which it already refers. 605 if (getLangOptions().CPlusPlus) { 606 if (!isa<CXXRecordDecl>(CurContext)) 607 return; 608 Diag(New->getLocation(), diag::err_redefinition) 609 << New->getDeclName(); 610 Diag(Old->getLocation(), diag::note_previous_definition); 611 return New->setInvalidDecl(); 612 } 613 614 // If we have a redefinition of a typedef in C, emit a warning. This warning 615 // is normally mapped to an error, but can be controlled with 616 // -Wtypedef-redefinition. If either the original or the redefinition is 617 // in a system header, don't emit this for compatibility with GCC. 618 if (PP.getDiagnostics().getSuppressSystemWarnings() && 619 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 620 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 621 return; 622 623 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 624 << New->getDeclName(); 625 Diag(Old->getLocation(), diag::note_previous_definition); 626 return; 627} 628 629/// DeclhasAttr - returns true if decl Declaration already has the target 630/// attribute. 631static bool 632DeclHasAttr(const Decl *decl, const Attr *target) { 633 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 634 if (attr->getKind() == target->getKind()) 635 return true; 636 637 return false; 638} 639 640/// MergeAttributes - append attributes from the Old decl to the New one. 641static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 642 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 643 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 644 Attr *NewAttr = attr->clone(C); 645 NewAttr->setInherited(true); 646 New->addAttr(NewAttr); 647 } 648 } 649} 650 651/// Used in MergeFunctionDecl to keep track of function parameters in 652/// C. 653struct GNUCompatibleParamWarning { 654 ParmVarDecl *OldParm; 655 ParmVarDecl *NewParm; 656 QualType PromotedType; 657}; 658 659/// MergeFunctionDecl - We just parsed a function 'New' from 660/// declarator D which has the same name and scope as a previous 661/// declaration 'Old'. Figure out how to resolve this situation, 662/// merging decls or emitting diagnostics as appropriate. 663/// 664/// In C++, New and Old must be declarations that are not 665/// overloaded. Use IsOverload to determine whether New and Old are 666/// overloaded, and to select the Old declaration that New should be 667/// merged with. 668/// 669/// Returns true if there was an error, false otherwise. 670bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 671 assert(!isa<OverloadedFunctionDecl>(OldD) && 672 "Cannot merge with an overloaded function declaration"); 673 674 // Verify the old decl was also a function. 675 FunctionDecl *Old = 0; 676 if (FunctionTemplateDecl *OldFunctionTemplate 677 = dyn_cast<FunctionTemplateDecl>(OldD)) 678 Old = OldFunctionTemplate->getTemplatedDecl(); 679 else 680 Old = dyn_cast<FunctionDecl>(OldD); 681 if (!Old) { 682 Diag(New->getLocation(), diag::err_redefinition_different_kind) 683 << New->getDeclName(); 684 Diag(OldD->getLocation(), diag::note_previous_definition); 685 return true; 686 } 687 688 // Determine whether the previous declaration was a definition, 689 // implicit declaration, or a declaration. 690 diag::kind PrevDiag; 691 if (Old->isThisDeclarationADefinition()) 692 PrevDiag = diag::note_previous_definition; 693 else if (Old->isImplicit()) 694 PrevDiag = diag::note_previous_implicit_declaration; 695 else 696 PrevDiag = diag::note_previous_declaration; 697 698 QualType OldQType = Context.getCanonicalType(Old->getType()); 699 QualType NewQType = Context.getCanonicalType(New->getType()); 700 701 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 702 New->getStorageClass() == FunctionDecl::Static && 703 Old->getStorageClass() != FunctionDecl::Static) { 704 Diag(New->getLocation(), diag::err_static_non_static) 705 << New; 706 Diag(Old->getLocation(), PrevDiag); 707 return true; 708 } 709 710 if (getLangOptions().CPlusPlus) { 711 // (C++98 13.1p2): 712 // Certain function declarations cannot be overloaded: 713 // -- Function declarations that differ only in the return type 714 // cannot be overloaded. 715 QualType OldReturnType 716 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 717 QualType NewReturnType 718 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 719 if (OldReturnType != NewReturnType) { 720 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 721 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 722 return true; 723 } 724 725 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 726 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 727 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 728 NewMethod->getLexicalDeclContext()->isRecord()) { 729 // -- Member function declarations with the same name and the 730 // same parameter types cannot be overloaded if any of them 731 // is a static member function declaration. 732 if (OldMethod->isStatic() || NewMethod->isStatic()) { 733 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 734 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 735 return true; 736 } 737 738 // C++ [class.mem]p1: 739 // [...] A member shall not be declared twice in the 740 // member-specification, except that a nested class or member 741 // class template can be declared and then later defined. 742 unsigned NewDiag; 743 if (isa<CXXConstructorDecl>(OldMethod)) 744 NewDiag = diag::err_constructor_redeclared; 745 else if (isa<CXXDestructorDecl>(NewMethod)) 746 NewDiag = diag::err_destructor_redeclared; 747 else if (isa<CXXConversionDecl>(NewMethod)) 748 NewDiag = diag::err_conv_function_redeclared; 749 else 750 NewDiag = diag::err_member_redeclared; 751 752 Diag(New->getLocation(), NewDiag); 753 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 754 } 755 756 // (C++98 8.3.5p3): 757 // All declarations for a function shall agree exactly in both the 758 // return type and the parameter-type-list. 759 if (OldQType == NewQType) 760 return MergeCompatibleFunctionDecls(New, Old); 761 762 // Fall through for conflicting redeclarations and redefinitions. 763 } 764 765 // C: Function types need to be compatible, not identical. This handles 766 // duplicate function decls like "void f(int); void f(enum X);" properly. 767 if (!getLangOptions().CPlusPlus && 768 Context.typesAreCompatible(OldQType, NewQType)) { 769 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 770 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 771 const FunctionProtoType *OldProto = 0; 772 if (isa<FunctionNoProtoType>(NewFuncType) && 773 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 774 // The old declaration provided a function prototype, but the 775 // new declaration does not. Merge in the prototype. 776 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 777 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 778 OldProto->arg_type_end()); 779 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 780 ParamTypes.data(), ParamTypes.size(), 781 OldProto->isVariadic(), 782 OldProto->getTypeQuals()); 783 New->setType(NewQType); 784 New->setHasInheritedPrototype(); 785 786 // Synthesize a parameter for each argument type. 787 llvm::SmallVector<ParmVarDecl*, 16> Params; 788 for (FunctionProtoType::arg_type_iterator 789 ParamType = OldProto->arg_type_begin(), 790 ParamEnd = OldProto->arg_type_end(); 791 ParamType != ParamEnd; ++ParamType) { 792 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 793 SourceLocation(), 0, 794 *ParamType, /*DInfo=*/0, 795 VarDecl::None, 0); 796 Param->setImplicit(); 797 Params.push_back(Param); 798 } 799 800 New->setParams(Context, Params.data(), Params.size()); 801 } 802 803 return MergeCompatibleFunctionDecls(New, Old); 804 } 805 806 // GNU C permits a K&R definition to follow a prototype declaration 807 // if the declared types of the parameters in the K&R definition 808 // match the types in the prototype declaration, even when the 809 // promoted types of the parameters from the K&R definition differ 810 // from the types in the prototype. GCC then keeps the types from 811 // the prototype. 812 // 813 // If a variadic prototype is followed by a non-variadic K&R definition, 814 // the K&R definition becomes variadic. This is sort of an edge case, but 815 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 816 // C99 6.9.1p8. 817 if (!getLangOptions().CPlusPlus && 818 Old->hasPrototype() && !New->hasPrototype() && 819 New->getType()->getAs<FunctionProtoType>() && 820 Old->getNumParams() == New->getNumParams()) { 821 llvm::SmallVector<QualType, 16> ArgTypes; 822 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 823 const FunctionProtoType *OldProto 824 = Old->getType()->getAs<FunctionProtoType>(); 825 const FunctionProtoType *NewProto 826 = New->getType()->getAs<FunctionProtoType>(); 827 828 // Determine whether this is the GNU C extension. 829 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 830 NewProto->getResultType()); 831 bool LooseCompatible = !MergedReturn.isNull(); 832 for (unsigned Idx = 0, End = Old->getNumParams(); 833 LooseCompatible && Idx != End; ++Idx) { 834 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 835 ParmVarDecl *NewParm = New->getParamDecl(Idx); 836 if (Context.typesAreCompatible(OldParm->getType(), 837 NewProto->getArgType(Idx))) { 838 ArgTypes.push_back(NewParm->getType()); 839 } else if (Context.typesAreCompatible(OldParm->getType(), 840 NewParm->getType())) { 841 GNUCompatibleParamWarning Warn 842 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 843 Warnings.push_back(Warn); 844 ArgTypes.push_back(NewParm->getType()); 845 } else 846 LooseCompatible = false; 847 } 848 849 if (LooseCompatible) { 850 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 851 Diag(Warnings[Warn].NewParm->getLocation(), 852 diag::ext_param_promoted_not_compatible_with_prototype) 853 << Warnings[Warn].PromotedType 854 << Warnings[Warn].OldParm->getType(); 855 Diag(Warnings[Warn].OldParm->getLocation(), 856 diag::note_previous_declaration); 857 } 858 859 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 860 ArgTypes.size(), 861 OldProto->isVariadic(), 0)); 862 return MergeCompatibleFunctionDecls(New, Old); 863 } 864 865 // Fall through to diagnose conflicting types. 866 } 867 868 // A function that has already been declared has been redeclared or defined 869 // with a different type- show appropriate diagnostic 870 if (unsigned BuiltinID = Old->getBuiltinID()) { 871 // The user has declared a builtin function with an incompatible 872 // signature. 873 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 874 // The function the user is redeclaring is a library-defined 875 // function like 'malloc' or 'printf'. Warn about the 876 // redeclaration, then pretend that we don't know about this 877 // library built-in. 878 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 879 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 880 << Old << Old->getType(); 881 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 882 Old->setInvalidDecl(); 883 return false; 884 } 885 886 PrevDiag = diag::note_previous_builtin_declaration; 887 } 888 889 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 890 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 891 return true; 892} 893 894/// \brief Completes the merge of two function declarations that are 895/// known to be compatible. 896/// 897/// This routine handles the merging of attributes and other 898/// properties of function declarations form the old declaration to 899/// the new declaration, once we know that New is in fact a 900/// redeclaration of Old. 901/// 902/// \returns false 903bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 904 // Merge the attributes 905 MergeAttributes(New, Old, Context); 906 907 // Merge the storage class. 908 if (Old->getStorageClass() != FunctionDecl::Extern && 909 Old->getStorageClass() != FunctionDecl::None) 910 New->setStorageClass(Old->getStorageClass()); 911 912 // Merge "pure" flag. 913 if (Old->isPure()) 914 New->setPure(); 915 916 // Merge the "deleted" flag. 917 if (Old->isDeleted()) 918 New->setDeleted(); 919 920 if (getLangOptions().CPlusPlus) 921 return MergeCXXFunctionDecl(New, Old); 922 923 return false; 924} 925 926/// MergeVarDecl - We just parsed a variable 'New' which has the same name 927/// and scope as a previous declaration 'Old'. Figure out how to resolve this 928/// situation, merging decls or emitting diagnostics as appropriate. 929/// 930/// Tentative definition rules (C99 6.9.2p2) are checked by 931/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 932/// definitions here, since the initializer hasn't been attached. 933/// 934void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 935 // If either decl is invalid, make sure the new one is marked invalid and 936 // don't do any other checking. 937 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 938 return New->setInvalidDecl(); 939 940 // Verify the old decl was also a variable. 941 VarDecl *Old = dyn_cast<VarDecl>(OldD); 942 if (!Old) { 943 Diag(New->getLocation(), diag::err_redefinition_different_kind) 944 << New->getDeclName(); 945 Diag(OldD->getLocation(), diag::note_previous_definition); 946 return New->setInvalidDecl(); 947 } 948 949 MergeAttributes(New, Old, Context); 950 951 // Merge the types 952 QualType MergedT; 953 if (getLangOptions().CPlusPlus) { 954 if (Context.hasSameType(New->getType(), Old->getType())) 955 MergedT = New->getType(); 956 // C++ [basic.types]p7: 957 // [...] The declared type of an array object might be an array of 958 // unknown size and therefore be incomplete at one point in a 959 // translation unit and complete later on; [...] 960 else if (Old->getType()->isIncompleteArrayType() && 961 New->getType()->isArrayType()) { 962 CanQual<ArrayType> OldArray 963 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 964 CanQual<ArrayType> NewArray 965 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 966 if (OldArray->getElementType() == NewArray->getElementType()) 967 MergedT = New->getType(); 968 } 969 } else { 970 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 971 } 972 if (MergedT.isNull()) { 973 Diag(New->getLocation(), diag::err_redefinition_different_type) 974 << New->getDeclName(); 975 Diag(Old->getLocation(), diag::note_previous_definition); 976 return New->setInvalidDecl(); 977 } 978 New->setType(MergedT); 979 980 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 981 if (New->getStorageClass() == VarDecl::Static && 982 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 983 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 984 Diag(Old->getLocation(), diag::note_previous_definition); 985 return New->setInvalidDecl(); 986 } 987 // C99 6.2.2p4: 988 // For an identifier declared with the storage-class specifier 989 // extern in a scope in which a prior declaration of that 990 // identifier is visible,23) if the prior declaration specifies 991 // internal or external linkage, the linkage of the identifier at 992 // the later declaration is the same as the linkage specified at 993 // the prior declaration. If no prior declaration is visible, or 994 // if the prior declaration specifies no linkage, then the 995 // identifier has external linkage. 996 if (New->hasExternalStorage() && Old->hasLinkage()) 997 /* Okay */; 998 else if (New->getStorageClass() != VarDecl::Static && 999 Old->getStorageClass() == VarDecl::Static) { 1000 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1001 Diag(Old->getLocation(), diag::note_previous_definition); 1002 return New->setInvalidDecl(); 1003 } 1004 1005 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1006 1007 // FIXME: The test for external storage here seems wrong? We still 1008 // need to check for mismatches. 1009 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1010 // Don't complain about out-of-line definitions of static members. 1011 !(Old->getLexicalDeclContext()->isRecord() && 1012 !New->getLexicalDeclContext()->isRecord())) { 1013 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1014 Diag(Old->getLocation(), diag::note_previous_definition); 1015 return New->setInvalidDecl(); 1016 } 1017 1018 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1019 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1020 Diag(Old->getLocation(), diag::note_previous_definition); 1021 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1022 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1023 Diag(Old->getLocation(), diag::note_previous_definition); 1024 } 1025 1026 // Keep a chain of previous declarations. 1027 New->setPreviousDeclaration(Old); 1028} 1029 1030/// CheckFallThrough - Check that we don't fall off the end of a 1031/// Statement that should return a value. 1032/// 1033/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1034/// MaybeFallThrough iff we might or might not fall off the end and 1035/// NeverFallThrough iff we never fall off the end of the statement. We assume 1036/// that functions not marked noreturn will return. 1037Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1038 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1039 1040 // FIXME: They should never return 0, fix that, delete this code. 1041 if (cfg == 0) 1042 return NeverFallThrough; 1043 // The CFG leaves in dead things, and we don't want to dead code paths to 1044 // confuse us, so we mark all live things first. 1045 std::queue<CFGBlock*> workq; 1046 llvm::BitVector live(cfg->getNumBlockIDs()); 1047 // Prep work queue 1048 workq.push(&cfg->getEntry()); 1049 // Solve 1050 while (!workq.empty()) { 1051 CFGBlock *item = workq.front(); 1052 workq.pop(); 1053 live.set(item->getBlockID()); 1054 for (CFGBlock::succ_iterator I=item->succ_begin(), 1055 E=item->succ_end(); 1056 I != E; 1057 ++I) { 1058 if ((*I) && !live[(*I)->getBlockID()]) { 1059 live.set((*I)->getBlockID()); 1060 workq.push(*I); 1061 } 1062 } 1063 } 1064 1065 // Now we know what is live, we check the live precessors of the exit block 1066 // and look for fall through paths, being careful to ignore normal returns, 1067 // and exceptional paths. 1068 bool HasLiveReturn = false; 1069 bool HasFakeEdge = false; 1070 bool HasPlainEdge = false; 1071 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1072 E = cfg->getExit().pred_end(); 1073 I != E; 1074 ++I) { 1075 CFGBlock& B = **I; 1076 if (!live[B.getBlockID()]) 1077 continue; 1078 if (B.size() == 0) { 1079 // A labeled empty statement, or the entry block... 1080 HasPlainEdge = true; 1081 continue; 1082 } 1083 Stmt *S = B[B.size()-1]; 1084 if (isa<ReturnStmt>(S)) { 1085 HasLiveReturn = true; 1086 continue; 1087 } 1088 if (isa<ObjCAtThrowStmt>(S)) { 1089 HasFakeEdge = true; 1090 continue; 1091 } 1092 if (isa<CXXThrowExpr>(S)) { 1093 HasFakeEdge = true; 1094 continue; 1095 } 1096 bool NoReturnEdge = false; 1097 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1098 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1099 if (CEE->getType().getNoReturnAttr()) { 1100 NoReturnEdge = true; 1101 HasFakeEdge = true; 1102 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1103 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1104 if (FD->hasAttr<NoReturnAttr>()) { 1105 NoReturnEdge = true; 1106 HasFakeEdge = true; 1107 } 1108 } 1109 } 1110 } 1111 // FIXME: Add noreturn message sends. 1112 if (NoReturnEdge == false) 1113 HasPlainEdge = true; 1114 } 1115 if (!HasPlainEdge) 1116 return NeverFallThrough; 1117 if (HasFakeEdge || HasLiveReturn) 1118 return MaybeFallThrough; 1119 // This says AlwaysFallThrough for calls to functions that are not marked 1120 // noreturn, that don't return. If people would like this warning to be more 1121 // accurate, such functions should be marked as noreturn. 1122 return AlwaysFallThrough; 1123} 1124 1125/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1126/// function that should return a value. Check that we don't fall off the end 1127/// of a noreturn function. We assume that functions and blocks not marked 1128/// noreturn will return. 1129void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1130 // FIXME: Would be nice if we had a better way to control cascading errors, 1131 // but for now, avoid them. The problem is that when Parse sees: 1132 // int foo() { return a; } 1133 // The return is eaten and the Sema code sees just: 1134 // int foo() { } 1135 // which this code would then warn about. 1136 if (getDiagnostics().hasErrorOccurred()) 1137 return; 1138 bool ReturnsVoid = false; 1139 bool HasNoReturn = false; 1140 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1141 if (FD->getResultType()->isVoidType()) 1142 ReturnsVoid = true; 1143 if (FD->hasAttr<NoReturnAttr>()) 1144 HasNoReturn = true; 1145 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1146 if (MD->getResultType()->isVoidType()) 1147 ReturnsVoid = true; 1148 if (MD->hasAttr<NoReturnAttr>()) 1149 HasNoReturn = true; 1150 } 1151 1152 // Short circuit for compilation speed. 1153 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1154 == Diagnostic::Ignored || ReturnsVoid) 1155 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1156 == Diagnostic::Ignored || !HasNoReturn) 1157 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1158 == Diagnostic::Ignored || !ReturnsVoid)) 1159 return; 1160 // FIXME: Funtion try block 1161 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1162 switch (CheckFallThrough(Body)) { 1163 case MaybeFallThrough: 1164 if (HasNoReturn) 1165 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1166 else if (!ReturnsVoid) 1167 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1168 break; 1169 case AlwaysFallThrough: 1170 if (HasNoReturn) 1171 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1172 else if (!ReturnsVoid) 1173 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1174 break; 1175 case NeverFallThrough: 1176 if (ReturnsVoid) 1177 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1178 break; 1179 } 1180 } 1181} 1182 1183/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1184/// that should return a value. Check that we don't fall off the end of a 1185/// noreturn block. We assume that functions and blocks not marked noreturn 1186/// will return. 1187void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1188 // FIXME: Would be nice if we had a better way to control cascading errors, 1189 // but for now, avoid them. The problem is that when Parse sees: 1190 // int foo() { return a; } 1191 // The return is eaten and the Sema code sees just: 1192 // int foo() { } 1193 // which this code would then warn about. 1194 if (getDiagnostics().hasErrorOccurred()) 1195 return; 1196 bool ReturnsVoid = false; 1197 bool HasNoReturn = false; 1198 if (const FunctionType *FT = BlockTy->getPointeeType()->getAs<FunctionType>()) { 1199 if (FT->getResultType()->isVoidType()) 1200 ReturnsVoid = true; 1201 if (FT->getNoReturnAttr()) 1202 HasNoReturn = true; 1203 } 1204 1205 // Short circuit for compilation speed. 1206 if (ReturnsVoid 1207 && !HasNoReturn 1208 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1209 == Diagnostic::Ignored || !ReturnsVoid)) 1210 return; 1211 // FIXME: Funtion try block 1212 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1213 switch (CheckFallThrough(Body)) { 1214 case MaybeFallThrough: 1215 if (HasNoReturn) 1216 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1217 else if (!ReturnsVoid) 1218 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1219 break; 1220 case AlwaysFallThrough: 1221 if (HasNoReturn) 1222 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1223 else if (!ReturnsVoid) 1224 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1225 break; 1226 case NeverFallThrough: 1227 if (ReturnsVoid) 1228 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1229 break; 1230 } 1231 } 1232} 1233 1234/// CheckParmsForFunctionDef - Check that the parameters of the given 1235/// function are appropriate for the definition of a function. This 1236/// takes care of any checks that cannot be performed on the 1237/// declaration itself, e.g., that the types of each of the function 1238/// parameters are complete. 1239bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1240 bool HasInvalidParm = false; 1241 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1242 ParmVarDecl *Param = FD->getParamDecl(p); 1243 1244 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1245 // function declarator that is part of a function definition of 1246 // that function shall not have incomplete type. 1247 // 1248 // This is also C++ [dcl.fct]p6. 1249 if (!Param->isInvalidDecl() && 1250 RequireCompleteType(Param->getLocation(), Param->getType(), 1251 diag::err_typecheck_decl_incomplete_type)) { 1252 Param->setInvalidDecl(); 1253 HasInvalidParm = true; 1254 } 1255 1256 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1257 // declaration of each parameter shall include an identifier. 1258 if (Param->getIdentifier() == 0 && 1259 !Param->isImplicit() && 1260 !getLangOptions().CPlusPlus) 1261 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1262 } 1263 1264 return HasInvalidParm; 1265} 1266 1267/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1268/// no declarator (e.g. "struct foo;") is parsed. 1269Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1270 // FIXME: Error on auto/register at file scope 1271 // FIXME: Error on inline/virtual/explicit 1272 // FIXME: Error on invalid restrict 1273 // FIXME: Warn on useless __thread 1274 // FIXME: Warn on useless const/volatile 1275 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1276 // FIXME: Warn on useless attributes 1277 TagDecl *Tag = 0; 1278 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1279 DS.getTypeSpecType() == DeclSpec::TST_struct || 1280 DS.getTypeSpecType() == DeclSpec::TST_union || 1281 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1282 if (!DS.getTypeRep()) // We probably had an error 1283 return DeclPtrTy(); 1284 1285 // Note that the above type specs guarantee that the 1286 // type rep is a Decl, whereas in many of the others 1287 // it's a Type. 1288 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1289 } 1290 1291 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1292 if (!Record->getDeclName() && Record->isDefinition() && 1293 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1294 if (getLangOptions().CPlusPlus || 1295 Record->getDeclContext()->isRecord()) 1296 return BuildAnonymousStructOrUnion(S, DS, Record); 1297 1298 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1299 << DS.getSourceRange(); 1300 } 1301 1302 // Microsoft allows unnamed struct/union fields. Don't complain 1303 // about them. 1304 // FIXME: Should we support Microsoft's extensions in this area? 1305 if (Record->getDeclName() && getLangOptions().Microsoft) 1306 return DeclPtrTy::make(Tag); 1307 } 1308 1309 if (!DS.isMissingDeclaratorOk() && 1310 DS.getTypeSpecType() != DeclSpec::TST_error) { 1311 // Warn about typedefs of enums without names, since this is an 1312 // extension in both Microsoft an GNU. 1313 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1314 Tag && isa<EnumDecl>(Tag)) { 1315 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1316 << DS.getSourceRange(); 1317 return DeclPtrTy::make(Tag); 1318 } 1319 1320 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1321 << DS.getSourceRange(); 1322 return DeclPtrTy(); 1323 } 1324 1325 return DeclPtrTy::make(Tag); 1326} 1327 1328/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1329/// anonymous struct or union AnonRecord into the owning context Owner 1330/// and scope S. This routine will be invoked just after we realize 1331/// that an unnamed union or struct is actually an anonymous union or 1332/// struct, e.g., 1333/// 1334/// @code 1335/// union { 1336/// int i; 1337/// float f; 1338/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1339/// // f into the surrounding scope.x 1340/// @endcode 1341/// 1342/// This routine is recursive, injecting the names of nested anonymous 1343/// structs/unions into the owning context and scope as well. 1344bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1345 RecordDecl *AnonRecord) { 1346 bool Invalid = false; 1347 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1348 FEnd = AnonRecord->field_end(); 1349 F != FEnd; ++F) { 1350 if ((*F)->getDeclName()) { 1351 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1352 LookupOrdinaryName, true); 1353 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1354 // C++ [class.union]p2: 1355 // The names of the members of an anonymous union shall be 1356 // distinct from the names of any other entity in the 1357 // scope in which the anonymous union is declared. 1358 unsigned diagKind 1359 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1360 : diag::err_anonymous_struct_member_redecl; 1361 Diag((*F)->getLocation(), diagKind) 1362 << (*F)->getDeclName(); 1363 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1364 Invalid = true; 1365 } else { 1366 // C++ [class.union]p2: 1367 // For the purpose of name lookup, after the anonymous union 1368 // definition, the members of the anonymous union are 1369 // considered to have been defined in the scope in which the 1370 // anonymous union is declared. 1371 Owner->makeDeclVisibleInContext(*F); 1372 S->AddDecl(DeclPtrTy::make(*F)); 1373 IdResolver.AddDecl(*F); 1374 } 1375 } else if (const RecordType *InnerRecordType 1376 = (*F)->getType()->getAs<RecordType>()) { 1377 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1378 if (InnerRecord->isAnonymousStructOrUnion()) 1379 Invalid = Invalid || 1380 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1381 } 1382 } 1383 1384 return Invalid; 1385} 1386 1387/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1388/// anonymous structure or union. Anonymous unions are a C++ feature 1389/// (C++ [class.union]) and a GNU C extension; anonymous structures 1390/// are a GNU C and GNU C++ extension. 1391Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1392 RecordDecl *Record) { 1393 DeclContext *Owner = Record->getDeclContext(); 1394 1395 // Diagnose whether this anonymous struct/union is an extension. 1396 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1397 Diag(Record->getLocation(), diag::ext_anonymous_union); 1398 else if (!Record->isUnion()) 1399 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1400 1401 // C and C++ require different kinds of checks for anonymous 1402 // structs/unions. 1403 bool Invalid = false; 1404 if (getLangOptions().CPlusPlus) { 1405 const char* PrevSpec = 0; 1406 unsigned DiagID; 1407 // C++ [class.union]p3: 1408 // Anonymous unions declared in a named namespace or in the 1409 // global namespace shall be declared static. 1410 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1411 (isa<TranslationUnitDecl>(Owner) || 1412 (isa<NamespaceDecl>(Owner) && 1413 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1414 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1415 Invalid = true; 1416 1417 // Recover by adding 'static'. 1418 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1419 PrevSpec, DiagID); 1420 } 1421 // C++ [class.union]p3: 1422 // A storage class is not allowed in a declaration of an 1423 // anonymous union in a class scope. 1424 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1425 isa<RecordDecl>(Owner)) { 1426 Diag(DS.getStorageClassSpecLoc(), 1427 diag::err_anonymous_union_with_storage_spec); 1428 Invalid = true; 1429 1430 // Recover by removing the storage specifier. 1431 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1432 PrevSpec, DiagID); 1433 } 1434 1435 // C++ [class.union]p2: 1436 // The member-specification of an anonymous union shall only 1437 // define non-static data members. [Note: nested types and 1438 // functions cannot be declared within an anonymous union. ] 1439 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1440 MemEnd = Record->decls_end(); 1441 Mem != MemEnd; ++Mem) { 1442 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1443 // C++ [class.union]p3: 1444 // An anonymous union shall not have private or protected 1445 // members (clause 11). 1446 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1447 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1448 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1449 Invalid = true; 1450 } 1451 } else if ((*Mem)->isImplicit()) { 1452 // Any implicit members are fine. 1453 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1454 // This is a type that showed up in an 1455 // elaborated-type-specifier inside the anonymous struct or 1456 // union, but which actually declares a type outside of the 1457 // anonymous struct or union. It's okay. 1458 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1459 if (!MemRecord->isAnonymousStructOrUnion() && 1460 MemRecord->getDeclName()) { 1461 // This is a nested type declaration. 1462 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1463 << (int)Record->isUnion(); 1464 Invalid = true; 1465 } 1466 } else { 1467 // We have something that isn't a non-static data 1468 // member. Complain about it. 1469 unsigned DK = diag::err_anonymous_record_bad_member; 1470 if (isa<TypeDecl>(*Mem)) 1471 DK = diag::err_anonymous_record_with_type; 1472 else if (isa<FunctionDecl>(*Mem)) 1473 DK = diag::err_anonymous_record_with_function; 1474 else if (isa<VarDecl>(*Mem)) 1475 DK = diag::err_anonymous_record_with_static; 1476 Diag((*Mem)->getLocation(), DK) 1477 << (int)Record->isUnion(); 1478 Invalid = true; 1479 } 1480 } 1481 } 1482 1483 if (!Record->isUnion() && !Owner->isRecord()) { 1484 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1485 << (int)getLangOptions().CPlusPlus; 1486 Invalid = true; 1487 } 1488 1489 // Create a declaration for this anonymous struct/union. 1490 NamedDecl *Anon = 0; 1491 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1492 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1493 /*IdentifierInfo=*/0, 1494 Context.getTypeDeclType(Record), 1495 // FIXME: Type source info. 1496 /*DInfo=*/0, 1497 /*BitWidth=*/0, /*Mutable=*/false); 1498 Anon->setAccess(AS_public); 1499 if (getLangOptions().CPlusPlus) 1500 FieldCollector->Add(cast<FieldDecl>(Anon)); 1501 } else { 1502 VarDecl::StorageClass SC; 1503 switch (DS.getStorageClassSpec()) { 1504 default: assert(0 && "Unknown storage class!"); 1505 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1506 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1507 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1508 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1509 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1510 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1511 case DeclSpec::SCS_mutable: 1512 // mutable can only appear on non-static class members, so it's always 1513 // an error here 1514 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1515 Invalid = true; 1516 SC = VarDecl::None; 1517 break; 1518 } 1519 1520 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1521 /*IdentifierInfo=*/0, 1522 Context.getTypeDeclType(Record), 1523 // FIXME: Type source info. 1524 /*DInfo=*/0, 1525 SC); 1526 } 1527 Anon->setImplicit(); 1528 1529 // Add the anonymous struct/union object to the current 1530 // context. We'll be referencing this object when we refer to one of 1531 // its members. 1532 Owner->addDecl(Anon); 1533 1534 // Inject the members of the anonymous struct/union into the owning 1535 // context and into the identifier resolver chain for name lookup 1536 // purposes. 1537 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1538 Invalid = true; 1539 1540 // Mark this as an anonymous struct/union type. Note that we do not 1541 // do this until after we have already checked and injected the 1542 // members of this anonymous struct/union type, because otherwise 1543 // the members could be injected twice: once by DeclContext when it 1544 // builds its lookup table, and once by 1545 // InjectAnonymousStructOrUnionMembers. 1546 Record->setAnonymousStructOrUnion(true); 1547 1548 if (Invalid) 1549 Anon->setInvalidDecl(); 1550 1551 return DeclPtrTy::make(Anon); 1552} 1553 1554 1555/// GetNameForDeclarator - Determine the full declaration name for the 1556/// given Declarator. 1557DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1558 switch (D.getKind()) { 1559 case Declarator::DK_Abstract: 1560 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1561 return DeclarationName(); 1562 1563 case Declarator::DK_Normal: 1564 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1565 return DeclarationName(D.getIdentifier()); 1566 1567 case Declarator::DK_Constructor: { 1568 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1569 return Context.DeclarationNames.getCXXConstructorName( 1570 Context.getCanonicalType(Ty)); 1571 } 1572 1573 case Declarator::DK_Destructor: { 1574 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1575 return Context.DeclarationNames.getCXXDestructorName( 1576 Context.getCanonicalType(Ty)); 1577 } 1578 1579 case Declarator::DK_Conversion: { 1580 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1581 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1582 return Context.DeclarationNames.getCXXConversionFunctionName( 1583 Context.getCanonicalType(Ty)); 1584 } 1585 1586 case Declarator::DK_Operator: 1587 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1588 return Context.DeclarationNames.getCXXOperatorName( 1589 D.getOverloadedOperator()); 1590 1591 case Declarator::DK_TemplateId: { 1592 TemplateName Name 1593 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1594 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1595 return Template->getDeclName(); 1596 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1597 return Ovl->getDeclName(); 1598 1599 return DeclarationName(); 1600 } 1601 } 1602 1603 assert(false && "Unknown name kind"); 1604 return DeclarationName(); 1605} 1606 1607/// isNearlyMatchingFunction - Determine whether the C++ functions 1608/// Declaration and Definition are "nearly" matching. This heuristic 1609/// is used to improve diagnostics in the case where an out-of-line 1610/// function definition doesn't match any declaration within 1611/// the class or namespace. 1612static bool isNearlyMatchingFunction(ASTContext &Context, 1613 FunctionDecl *Declaration, 1614 FunctionDecl *Definition) { 1615 if (Declaration->param_size() != Definition->param_size()) 1616 return false; 1617 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1618 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1619 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1620 1621 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1622 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1623 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1624 return false; 1625 } 1626 1627 return true; 1628} 1629 1630Sema::DeclPtrTy 1631Sema::HandleDeclarator(Scope *S, Declarator &D, 1632 MultiTemplateParamsArg TemplateParamLists, 1633 bool IsFunctionDefinition) { 1634 DeclarationName Name = GetNameForDeclarator(D); 1635 1636 // All of these full declarators require an identifier. If it doesn't have 1637 // one, the ParsedFreeStandingDeclSpec action should be used. 1638 if (!Name) { 1639 if (!D.isInvalidType()) // Reject this if we think it is valid. 1640 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1641 diag::err_declarator_need_ident) 1642 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1643 return DeclPtrTy(); 1644 } 1645 1646 // The scope passed in may not be a decl scope. Zip up the scope tree until 1647 // we find one that is. 1648 while ((S->getFlags() & Scope::DeclScope) == 0 || 1649 (S->getFlags() & Scope::TemplateParamScope) != 0) 1650 S = S->getParent(); 1651 1652 // If this is an out-of-line definition of a member of a class template 1653 // or class template partial specialization, we may need to rebuild the 1654 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1655 // for more information. 1656 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1657 // handle expressions properly. 1658 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1659 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1660 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1661 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1662 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1663 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1664 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1665 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1666 // FIXME: Preserve type source info. 1667 QualType T = GetTypeFromParser(DS.getTypeRep()); 1668 EnterDeclaratorContext(S, DC); 1669 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1670 ExitDeclaratorContext(S); 1671 if (T.isNull()) 1672 return DeclPtrTy(); 1673 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1674 } 1675 } 1676 1677 DeclContext *DC; 1678 NamedDecl *PrevDecl; 1679 NamedDecl *New; 1680 1681 DeclaratorInfo *DInfo = 0; 1682 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1683 1684 // See if this is a redefinition of a variable in the same scope. 1685 if (D.getCXXScopeSpec().isInvalid()) { 1686 DC = CurContext; 1687 PrevDecl = 0; 1688 D.setInvalidType(); 1689 } else if (!D.getCXXScopeSpec().isSet()) { 1690 LookupNameKind NameKind = LookupOrdinaryName; 1691 1692 // If the declaration we're planning to build will be a function 1693 // or object with linkage, then look for another declaration with 1694 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1695 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1696 /* Do nothing*/; 1697 else if (R->isFunctionType()) { 1698 if (CurContext->isFunctionOrMethod() || 1699 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1700 NameKind = LookupRedeclarationWithLinkage; 1701 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1702 NameKind = LookupRedeclarationWithLinkage; 1703 else if (CurContext->getLookupContext()->isTranslationUnit() && 1704 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1705 NameKind = LookupRedeclarationWithLinkage; 1706 1707 DC = CurContext; 1708 PrevDecl = LookupName(S, Name, NameKind, true, 1709 NameKind == LookupRedeclarationWithLinkage, 1710 D.getIdentifierLoc()); 1711 } else { // Something like "int foo::x;" 1712 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1713 1714 if (!DC) { 1715 // If we could not compute the declaration context, it's because the 1716 // declaration context is dependent but does not refer to a class, 1717 // class template, or class template partial specialization. Complain 1718 // and return early, to avoid the coming semantic disaster. 1719 Diag(D.getIdentifierLoc(), 1720 diag::err_template_qualified_declarator_no_match) 1721 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1722 << D.getCXXScopeSpec().getRange(); 1723 return DeclPtrTy(); 1724 } 1725 1726 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1727 1728 // C++ 7.3.1.2p2: 1729 // Members (including explicit specializations of templates) of a named 1730 // namespace can also be defined outside that namespace by explicit 1731 // qualification of the name being defined, provided that the entity being 1732 // defined was already declared in the namespace and the definition appears 1733 // after the point of declaration in a namespace that encloses the 1734 // declarations namespace. 1735 // 1736 // Note that we only check the context at this point. We don't yet 1737 // have enough information to make sure that PrevDecl is actually 1738 // the declaration we want to match. For example, given: 1739 // 1740 // class X { 1741 // void f(); 1742 // void f(float); 1743 // }; 1744 // 1745 // void X::f(int) { } // ill-formed 1746 // 1747 // In this case, PrevDecl will point to the overload set 1748 // containing the two f's declared in X, but neither of them 1749 // matches. 1750 1751 // First check whether we named the global scope. 1752 if (isa<TranslationUnitDecl>(DC)) { 1753 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1754 << Name << D.getCXXScopeSpec().getRange(); 1755 } else if (!CurContext->Encloses(DC)) { 1756 // The qualifying scope doesn't enclose the original declaration. 1757 // Emit diagnostic based on current scope. 1758 SourceLocation L = D.getIdentifierLoc(); 1759 SourceRange R = D.getCXXScopeSpec().getRange(); 1760 if (isa<FunctionDecl>(CurContext)) 1761 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1762 else 1763 Diag(L, diag::err_invalid_declarator_scope) 1764 << Name << cast<NamedDecl>(DC) << R; 1765 D.setInvalidType(); 1766 } 1767 } 1768 1769 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1770 // Maybe we will complain about the shadowed template parameter. 1771 if (!D.isInvalidType()) 1772 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1773 D.setInvalidType(); 1774 1775 // Just pretend that we didn't see the previous declaration. 1776 PrevDecl = 0; 1777 } 1778 1779 // In C++, the previous declaration we find might be a tag type 1780 // (class or enum). In this case, the new declaration will hide the 1781 // tag type. Note that this does does not apply if we're declaring a 1782 // typedef (C++ [dcl.typedef]p4). 1783 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1784 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1785 PrevDecl = 0; 1786 1787 bool Redeclaration = false; 1788 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1789 if (TemplateParamLists.size()) { 1790 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1791 return DeclPtrTy(); 1792 } 1793 1794 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1795 } else if (R->isFunctionType()) { 1796 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1797 move(TemplateParamLists), 1798 IsFunctionDefinition, Redeclaration); 1799 } else { 1800 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1801 move(TemplateParamLists), 1802 Redeclaration); 1803 } 1804 1805 if (New == 0) 1806 return DeclPtrTy(); 1807 1808 // If this has an identifier and is not an invalid redeclaration or 1809 // function template specialization, add it to the scope stack. 1810 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1811 !(isa<FunctionDecl>(New) && 1812 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1813 PushOnScopeChains(New, S); 1814 1815 return DeclPtrTy::make(New); 1816} 1817 1818/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1819/// types into constant array types in certain situations which would otherwise 1820/// be errors (for GCC compatibility). 1821static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1822 ASTContext &Context, 1823 bool &SizeIsNegative) { 1824 // This method tries to turn a variable array into a constant 1825 // array even when the size isn't an ICE. This is necessary 1826 // for compatibility with code that depends on gcc's buggy 1827 // constant expression folding, like struct {char x[(int)(char*)2];} 1828 SizeIsNegative = false; 1829 1830 QualifierCollector Qs; 1831 const Type *Ty = Qs.strip(T); 1832 1833 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1834 QualType Pointee = PTy->getPointeeType(); 1835 QualType FixedType = 1836 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1837 if (FixedType.isNull()) return FixedType; 1838 FixedType = Context.getPointerType(FixedType); 1839 return Qs.apply(FixedType); 1840 } 1841 1842 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1843 if (!VLATy) 1844 return QualType(); 1845 // FIXME: We should probably handle this case 1846 if (VLATy->getElementType()->isVariablyModifiedType()) 1847 return QualType(); 1848 1849 Expr::EvalResult EvalResult; 1850 if (!VLATy->getSizeExpr() || 1851 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1852 !EvalResult.Val.isInt()) 1853 return QualType(); 1854 1855 llvm::APSInt &Res = EvalResult.Val.getInt(); 1856 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1857 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1858 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1859 // so as to transfer ownership to the ConstantArrayWithExpr. 1860 // Alternatively, we could "clone" it (how?). 1861 // Since we don't know how to do things above, we just use the 1862 // very same Expr*. 1863 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1864 Res, ArySizeExpr, 1865 ArrayType::Normal, 0, 1866 VLATy->getBracketsRange()); 1867 } 1868 1869 SizeIsNegative = true; 1870 return QualType(); 1871} 1872 1873/// \brief Register the given locally-scoped external C declaration so 1874/// that it can be found later for redeclarations 1875void 1876Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1877 Scope *S) { 1878 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1879 "Decl is not a locally-scoped decl!"); 1880 // Note that we have a locally-scoped external with this name. 1881 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1882 1883 if (!PrevDecl) 1884 return; 1885 1886 // If there was a previous declaration of this variable, it may be 1887 // in our identifier chain. Update the identifier chain with the new 1888 // declaration. 1889 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1890 // The previous declaration was found on the identifer resolver 1891 // chain, so remove it from its scope. 1892 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1893 S = S->getParent(); 1894 1895 if (S) 1896 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1897 } 1898} 1899 1900/// \brief Diagnose function specifiers on a declaration of an identifier that 1901/// does not identify a function. 1902void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1903 // FIXME: We should probably indicate the identifier in question to avoid 1904 // confusion for constructs like "inline int a(), b;" 1905 if (D.getDeclSpec().isInlineSpecified()) 1906 Diag(D.getDeclSpec().getInlineSpecLoc(), 1907 diag::err_inline_non_function); 1908 1909 if (D.getDeclSpec().isVirtualSpecified()) 1910 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1911 diag::err_virtual_non_function); 1912 1913 if (D.getDeclSpec().isExplicitSpecified()) 1914 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1915 diag::err_explicit_non_function); 1916} 1917 1918NamedDecl* 1919Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1920 QualType R, DeclaratorInfo *DInfo, 1921 Decl* PrevDecl, bool &Redeclaration) { 1922 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1923 if (D.getCXXScopeSpec().isSet()) { 1924 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1925 << D.getCXXScopeSpec().getRange(); 1926 D.setInvalidType(); 1927 // Pretend we didn't see the scope specifier. 1928 DC = 0; 1929 } 1930 1931 if (getLangOptions().CPlusPlus) { 1932 // Check that there are no default arguments (C++ only). 1933 CheckExtraCXXDefaultArguments(D); 1934 } 1935 1936 DiagnoseFunctionSpecifiers(D); 1937 1938 if (D.getDeclSpec().isThreadSpecified()) 1939 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1940 1941 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1942 if (!NewTD) return 0; 1943 1944 if (D.isInvalidType()) 1945 NewTD->setInvalidDecl(); 1946 1947 // Handle attributes prior to checking for duplicates in MergeVarDecl 1948 ProcessDeclAttributes(S, NewTD, D); 1949 // Merge the decl with the existing one if appropriate. If the decl is 1950 // in an outer scope, it isn't the same thing. 1951 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1952 Redeclaration = true; 1953 MergeTypeDefDecl(NewTD, PrevDecl); 1954 } 1955 1956 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1957 // then it shall have block scope. 1958 QualType T = NewTD->getUnderlyingType(); 1959 if (T->isVariablyModifiedType()) { 1960 CurFunctionNeedsScopeChecking = true; 1961 1962 if (S->getFnParent() == 0) { 1963 bool SizeIsNegative; 1964 QualType FixedTy = 1965 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1966 if (!FixedTy.isNull()) { 1967 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1968 NewTD->setUnderlyingType(FixedTy); 1969 } else { 1970 if (SizeIsNegative) 1971 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1972 else if (T->isVariableArrayType()) 1973 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1974 else 1975 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1976 NewTD->setInvalidDecl(); 1977 } 1978 } 1979 } 1980 1981 // If this is the C FILE type, notify the AST context. 1982 if (IdentifierInfo *II = NewTD->getIdentifier()) 1983 if (!NewTD->isInvalidDecl() && 1984 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1985 if (II->isStr("FILE")) 1986 Context.setFILEDecl(NewTD); 1987 else if (II->isStr("jmp_buf")) 1988 Context.setjmp_bufDecl(NewTD); 1989 else if (II->isStr("sigjmp_buf")) 1990 Context.setsigjmp_bufDecl(NewTD); 1991 } 1992 1993 return NewTD; 1994} 1995 1996/// \brief Determines whether the given declaration is an out-of-scope 1997/// previous declaration. 1998/// 1999/// This routine should be invoked when name lookup has found a 2000/// previous declaration (PrevDecl) that is not in the scope where a 2001/// new declaration by the same name is being introduced. If the new 2002/// declaration occurs in a local scope, previous declarations with 2003/// linkage may still be considered previous declarations (C99 2004/// 6.2.2p4-5, C++ [basic.link]p6). 2005/// 2006/// \param PrevDecl the previous declaration found by name 2007/// lookup 2008/// 2009/// \param DC the context in which the new declaration is being 2010/// declared. 2011/// 2012/// \returns true if PrevDecl is an out-of-scope previous declaration 2013/// for a new delcaration with the same name. 2014static bool 2015isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2016 ASTContext &Context) { 2017 if (!PrevDecl) 2018 return 0; 2019 2020 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2021 // case we need to check each of the overloaded functions. 2022 if (!PrevDecl->hasLinkage()) 2023 return false; 2024 2025 if (Context.getLangOptions().CPlusPlus) { 2026 // C++ [basic.link]p6: 2027 // If there is a visible declaration of an entity with linkage 2028 // having the same name and type, ignoring entities declared 2029 // outside the innermost enclosing namespace scope, the block 2030 // scope declaration declares that same entity and receives the 2031 // linkage of the previous declaration. 2032 DeclContext *OuterContext = DC->getLookupContext(); 2033 if (!OuterContext->isFunctionOrMethod()) 2034 // This rule only applies to block-scope declarations. 2035 return false; 2036 else { 2037 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2038 if (PrevOuterContext->isRecord()) 2039 // We found a member function: ignore it. 2040 return false; 2041 else { 2042 // Find the innermost enclosing namespace for the new and 2043 // previous declarations. 2044 while (!OuterContext->isFileContext()) 2045 OuterContext = OuterContext->getParent(); 2046 while (!PrevOuterContext->isFileContext()) 2047 PrevOuterContext = PrevOuterContext->getParent(); 2048 2049 // The previous declaration is in a different namespace, so it 2050 // isn't the same function. 2051 if (OuterContext->getPrimaryContext() != 2052 PrevOuterContext->getPrimaryContext()) 2053 return false; 2054 } 2055 } 2056 } 2057 2058 return true; 2059} 2060 2061NamedDecl* 2062Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2063 QualType R, DeclaratorInfo *DInfo, 2064 NamedDecl* PrevDecl, 2065 MultiTemplateParamsArg TemplateParamLists, 2066 bool &Redeclaration) { 2067 DeclarationName Name = GetNameForDeclarator(D); 2068 2069 // Check that there are no default arguments (C++ only). 2070 if (getLangOptions().CPlusPlus) 2071 CheckExtraCXXDefaultArguments(D); 2072 2073 VarDecl *NewVD; 2074 VarDecl::StorageClass SC; 2075 switch (D.getDeclSpec().getStorageClassSpec()) { 2076 default: assert(0 && "Unknown storage class!"); 2077 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2078 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2079 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2080 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2081 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2082 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2083 case DeclSpec::SCS_mutable: 2084 // mutable can only appear on non-static class members, so it's always 2085 // an error here 2086 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2087 D.setInvalidType(); 2088 SC = VarDecl::None; 2089 break; 2090 } 2091 2092 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2093 if (!II) { 2094 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2095 << Name.getAsString(); 2096 return 0; 2097 } 2098 2099 DiagnoseFunctionSpecifiers(D); 2100 2101 if (!DC->isRecord() && S->getFnParent() == 0) { 2102 // C99 6.9p2: The storage-class specifiers auto and register shall not 2103 // appear in the declaration specifiers in an external declaration. 2104 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2105 2106 // If this is a register variable with an asm label specified, then this 2107 // is a GNU extension. 2108 if (SC == VarDecl::Register && D.getAsmLabel()) 2109 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2110 else 2111 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2112 D.setInvalidType(); 2113 } 2114 } 2115 if (DC->isRecord() && !CurContext->isRecord()) { 2116 // This is an out-of-line definition of a static data member. 2117 if (SC == VarDecl::Static) { 2118 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2119 diag::err_static_out_of_line) 2120 << CodeModificationHint::CreateRemoval( 2121 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2122 } else if (SC == VarDecl::None) 2123 SC = VarDecl::Static; 2124 } 2125 if (SC == VarDecl::Static) { 2126 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2127 if (RD->isLocalClass()) 2128 Diag(D.getIdentifierLoc(), 2129 diag::err_static_data_member_not_allowed_in_local_class) 2130 << Name << RD->getDeclName(); 2131 } 2132 } 2133 2134 // Match up the template parameter lists with the scope specifier, then 2135 // determine whether we have a template or a template specialization. 2136 if (TemplateParameterList *TemplateParams 2137 = MatchTemplateParametersToScopeSpecifier( 2138 D.getDeclSpec().getSourceRange().getBegin(), 2139 D.getCXXScopeSpec(), 2140 (TemplateParameterList**)TemplateParamLists.get(), 2141 TemplateParamLists.size())) { 2142 if (TemplateParams->size() > 0) { 2143 // There is no such thing as a variable template. 2144 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2145 << II 2146 << SourceRange(TemplateParams->getTemplateLoc(), 2147 TemplateParams->getRAngleLoc()); 2148 return 0; 2149 } else { 2150 // There is an extraneous 'template<>' for this variable. Complain 2151 // about it, but allow the declaration of the variable. 2152 Diag(TemplateParams->getTemplateLoc(), 2153 diag::err_template_variable_noparams) 2154 << II 2155 << SourceRange(TemplateParams->getTemplateLoc(), 2156 TemplateParams->getRAngleLoc()); 2157 } 2158 } 2159 2160 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2161 II, R, DInfo, SC); 2162 2163 if (D.isInvalidType()) 2164 NewVD->setInvalidDecl(); 2165 2166 if (D.getDeclSpec().isThreadSpecified()) { 2167 if (NewVD->hasLocalStorage()) 2168 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2169 else if (!Context.Target.isTLSSupported()) 2170 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2171 else 2172 NewVD->setThreadSpecified(true); 2173 } 2174 2175 // Set the lexical context. If the declarator has a C++ scope specifier, the 2176 // lexical context will be different from the semantic context. 2177 NewVD->setLexicalDeclContext(CurContext); 2178 2179 // Handle attributes prior to checking for duplicates in MergeVarDecl 2180 ProcessDeclAttributes(S, NewVD, D); 2181 2182 // Handle GNU asm-label extension (encoded as an attribute). 2183 if (Expr *E = (Expr*) D.getAsmLabel()) { 2184 // The parser guarantees this is a string. 2185 StringLiteral *SE = cast<StringLiteral>(E); 2186 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2187 SE->getByteLength()))); 2188 } 2189 2190 // If name lookup finds a previous declaration that is not in the 2191 // same scope as the new declaration, this may still be an 2192 // acceptable redeclaration. 2193 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2194 !(NewVD->hasLinkage() && 2195 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2196 PrevDecl = 0; 2197 2198 // Merge the decl with the existing one if appropriate. 2199 if (PrevDecl) { 2200 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2201 // The user tried to define a non-static data member 2202 // out-of-line (C++ [dcl.meaning]p1). 2203 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2204 << D.getCXXScopeSpec().getRange(); 2205 PrevDecl = 0; 2206 NewVD->setInvalidDecl(); 2207 } 2208 } else if (D.getCXXScopeSpec().isSet()) { 2209 // No previous declaration in the qualifying scope. 2210 NestedNameSpecifier *NNS = 2211 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2212 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2213 D.getCXXScopeSpec().getRange()); 2214 NewVD->setInvalidDecl(); 2215 } 2216 2217 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2218 2219 // attributes declared post-definition are currently ignored 2220 if (PrevDecl) { 2221 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2222 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2223 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2224 Diag(Def->getLocation(), diag::note_previous_definition); 2225 } 2226 } 2227 2228 // If this is a locally-scoped extern C variable, update the map of 2229 // such variables. 2230 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2231 !NewVD->isInvalidDecl()) 2232 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2233 2234 return NewVD; 2235} 2236 2237/// \brief Perform semantic checking on a newly-created variable 2238/// declaration. 2239/// 2240/// This routine performs all of the type-checking required for a 2241/// variable declaration once it has been built. It is used both to 2242/// check variables after they have been parsed and their declarators 2243/// have been translated into a declaration, and to check variables 2244/// that have been instantiated from a template. 2245/// 2246/// Sets NewVD->isInvalidDecl() if an error was encountered. 2247void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2248 bool &Redeclaration) { 2249 // If the decl is already known invalid, don't check it. 2250 if (NewVD->isInvalidDecl()) 2251 return; 2252 2253 QualType T = NewVD->getType(); 2254 2255 if (T->isObjCInterfaceType()) { 2256 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2257 return NewVD->setInvalidDecl(); 2258 } 2259 2260 // The variable can not have an abstract class type. 2261 if (RequireNonAbstractType(NewVD->getLocation(), T, 2262 diag::err_abstract_type_in_decl, 2263 AbstractVariableType)) 2264 return NewVD->setInvalidDecl(); 2265 2266 // Emit an error if an address space was applied to decl with local storage. 2267 // This includes arrays of objects with address space qualifiers, but not 2268 // automatic variables that point to other address spaces. 2269 // ISO/IEC TR 18037 S5.1.2 2270 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2271 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2272 return NewVD->setInvalidDecl(); 2273 } 2274 2275 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2276 && !NewVD->hasAttr<BlocksAttr>()) 2277 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2278 2279 bool isVM = T->isVariablyModifiedType(); 2280 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2281 NewVD->hasAttr<BlocksAttr>()) 2282 CurFunctionNeedsScopeChecking = true; 2283 2284 if ((isVM && NewVD->hasLinkage()) || 2285 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2286 bool SizeIsNegative; 2287 QualType FixedTy = 2288 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2289 2290 if (FixedTy.isNull() && T->isVariableArrayType()) { 2291 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2292 // FIXME: This won't give the correct result for 2293 // int a[10][n]; 2294 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2295 2296 if (NewVD->isFileVarDecl()) 2297 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2298 << SizeRange; 2299 else if (NewVD->getStorageClass() == VarDecl::Static) 2300 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2301 << SizeRange; 2302 else 2303 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2304 << SizeRange; 2305 return NewVD->setInvalidDecl(); 2306 } 2307 2308 if (FixedTy.isNull()) { 2309 if (NewVD->isFileVarDecl()) 2310 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2311 else 2312 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2313 return NewVD->setInvalidDecl(); 2314 } 2315 2316 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2317 NewVD->setType(FixedTy); 2318 } 2319 2320 if (!PrevDecl && NewVD->isExternC()) { 2321 // Since we did not find anything by this name and we're declaring 2322 // an extern "C" variable, look for a non-visible extern "C" 2323 // declaration with the same name. 2324 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2325 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2326 if (Pos != LocallyScopedExternalDecls.end()) 2327 PrevDecl = Pos->second; 2328 } 2329 2330 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2331 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2332 << T; 2333 return NewVD->setInvalidDecl(); 2334 } 2335 2336 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2337 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2338 return NewVD->setInvalidDecl(); 2339 } 2340 2341 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2342 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2343 return NewVD->setInvalidDecl(); 2344 } 2345 2346 if (PrevDecl) { 2347 Redeclaration = true; 2348 MergeVarDecl(NewVD, PrevDecl); 2349 } 2350} 2351 2352static bool isUsingDecl(Decl *D) { 2353 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2354} 2355 2356NamedDecl* 2357Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2358 QualType R, DeclaratorInfo *DInfo, 2359 NamedDecl* PrevDecl, 2360 MultiTemplateParamsArg TemplateParamLists, 2361 bool IsFunctionDefinition, bool &Redeclaration) { 2362 assert(R.getTypePtr()->isFunctionType()); 2363 2364 DeclarationName Name = GetNameForDeclarator(D); 2365 FunctionDecl::StorageClass SC = FunctionDecl::None; 2366 switch (D.getDeclSpec().getStorageClassSpec()) { 2367 default: assert(0 && "Unknown storage class!"); 2368 case DeclSpec::SCS_auto: 2369 case DeclSpec::SCS_register: 2370 case DeclSpec::SCS_mutable: 2371 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2372 diag::err_typecheck_sclass_func); 2373 D.setInvalidType(); 2374 break; 2375 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2376 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2377 case DeclSpec::SCS_static: { 2378 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2379 // C99 6.7.1p5: 2380 // The declaration of an identifier for a function that has 2381 // block scope shall have no explicit storage-class specifier 2382 // other than extern 2383 // See also (C++ [dcl.stc]p4). 2384 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2385 diag::err_static_block_func); 2386 SC = FunctionDecl::None; 2387 } else 2388 SC = FunctionDecl::Static; 2389 break; 2390 } 2391 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2392 } 2393 2394 if (D.getDeclSpec().isThreadSpecified()) 2395 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2396 2397 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2398 bool isInline = D.getDeclSpec().isInlineSpecified(); 2399 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2400 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2401 2402 // Check that the return type is not an abstract class type. 2403 // For record types, this is done by the AbstractClassUsageDiagnoser once 2404 // the class has been completely parsed. 2405 if (!DC->isRecord() && 2406 RequireNonAbstractType(D.getIdentifierLoc(), 2407 R->getAs<FunctionType>()->getResultType(), 2408 diag::err_abstract_type_in_decl, 2409 AbstractReturnType)) 2410 D.setInvalidType(); 2411 2412 // Do not allow returning a objc interface by-value. 2413 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2414 Diag(D.getIdentifierLoc(), 2415 diag::err_object_cannot_be_passed_returned_by_value) << 0 2416 << R->getAs<FunctionType>()->getResultType(); 2417 D.setInvalidType(); 2418 } 2419 2420 bool isVirtualOkay = false; 2421 FunctionDecl *NewFD; 2422 2423 if (isFriend) { 2424 // DC is the namespace in which the function is being declared. 2425 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2426 "friend function being created in a non-namespace context"); 2427 2428 // C++ [class.friend]p5 2429 // A function can be defined in a friend declaration of a 2430 // class . . . . Such a function is implicitly inline. 2431 isInline |= IsFunctionDefinition; 2432 } 2433 2434 if (D.getKind() == Declarator::DK_Constructor) { 2435 // This is a C++ constructor declaration. 2436 assert(DC->isRecord() && 2437 "Constructors can only be declared in a member context"); 2438 2439 R = CheckConstructorDeclarator(D, R, SC); 2440 2441 // Create the new declaration 2442 NewFD = CXXConstructorDecl::Create(Context, 2443 cast<CXXRecordDecl>(DC), 2444 D.getIdentifierLoc(), Name, R, DInfo, 2445 isExplicit, isInline, 2446 /*isImplicitlyDeclared=*/false); 2447 } else if (D.getKind() == Declarator::DK_Destructor) { 2448 // This is a C++ destructor declaration. 2449 if (DC->isRecord()) { 2450 R = CheckDestructorDeclarator(D, SC); 2451 2452 NewFD = CXXDestructorDecl::Create(Context, 2453 cast<CXXRecordDecl>(DC), 2454 D.getIdentifierLoc(), Name, R, 2455 isInline, 2456 /*isImplicitlyDeclared=*/false); 2457 2458 isVirtualOkay = true; 2459 } else { 2460 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2461 2462 // Create a FunctionDecl to satisfy the function definition parsing 2463 // code path. 2464 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2465 Name, R, DInfo, SC, isInline, 2466 /*hasPrototype=*/true); 2467 D.setInvalidType(); 2468 } 2469 } else if (D.getKind() == Declarator::DK_Conversion) { 2470 if (!DC->isRecord()) { 2471 Diag(D.getIdentifierLoc(), 2472 diag::err_conv_function_not_member); 2473 return 0; 2474 } 2475 2476 CheckConversionDeclarator(D, R, SC); 2477 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2478 D.getIdentifierLoc(), Name, R, DInfo, 2479 isInline, isExplicit); 2480 2481 isVirtualOkay = true; 2482 } else if (DC->isRecord()) { 2483 // If the of the function is the same as the name of the record, then this 2484 // must be an invalid constructor that has a return type. 2485 // (The parser checks for a return type and makes the declarator a 2486 // constructor if it has no return type). 2487 // must have an invalid constructor that has a return type 2488 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2489 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2490 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2491 << SourceRange(D.getIdentifierLoc()); 2492 return 0; 2493 } 2494 2495 // This is a C++ method declaration. 2496 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2497 D.getIdentifierLoc(), Name, R, DInfo, 2498 (SC == FunctionDecl::Static), isInline); 2499 2500 isVirtualOkay = (SC != FunctionDecl::Static); 2501 } else { 2502 // Determine whether the function was written with a 2503 // prototype. This true when: 2504 // - we're in C++ (where every function has a prototype), 2505 // - there is a prototype in the declarator, or 2506 // - the type R of the function is some kind of typedef or other reference 2507 // to a type name (which eventually refers to a function type). 2508 bool HasPrototype = 2509 getLangOptions().CPlusPlus || 2510 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2511 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2512 2513 NewFD = FunctionDecl::Create(Context, DC, 2514 D.getIdentifierLoc(), 2515 Name, R, DInfo, SC, isInline, HasPrototype); 2516 } 2517 2518 if (D.isInvalidType()) 2519 NewFD->setInvalidDecl(); 2520 2521 // Set the lexical context. If the declarator has a C++ 2522 // scope specifier, or is the object of a friend declaration, the 2523 // lexical context will be different from the semantic context. 2524 NewFD->setLexicalDeclContext(CurContext); 2525 2526 if (isFriend) 2527 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2528 2529 // Match up the template parameter lists with the scope specifier, then 2530 // determine whether we have a template or a template specialization. 2531 FunctionTemplateDecl *FunctionTemplate = 0; 2532 bool isFunctionTemplateSpecialization = false; 2533 if (TemplateParameterList *TemplateParams 2534 = MatchTemplateParametersToScopeSpecifier( 2535 D.getDeclSpec().getSourceRange().getBegin(), 2536 D.getCXXScopeSpec(), 2537 (TemplateParameterList**)TemplateParamLists.get(), 2538 TemplateParamLists.size())) { 2539 if (TemplateParams->size() > 0) { 2540 // This is a function template 2541 2542 // Check that we can declare a template here. 2543 if (CheckTemplateDeclScope(S, TemplateParams)) 2544 return 0; 2545 2546 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2547 NewFD->getLocation(), 2548 Name, TemplateParams, 2549 NewFD); 2550 FunctionTemplate->setLexicalDeclContext(CurContext); 2551 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2552 } else { 2553 // This is a function template specialization. 2554 isFunctionTemplateSpecialization = true; 2555 } 2556 2557 // FIXME: Free this memory properly. 2558 TemplateParamLists.release(); 2559 } 2560 2561 // C++ [dcl.fct.spec]p5: 2562 // The virtual specifier shall only be used in declarations of 2563 // nonstatic class member functions that appear within a 2564 // member-specification of a class declaration; see 10.3. 2565 // 2566 if (isVirtual && !NewFD->isInvalidDecl()) { 2567 if (!isVirtualOkay) { 2568 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2569 diag::err_virtual_non_function); 2570 } else if (!CurContext->isRecord()) { 2571 // 'virtual' was specified outside of the class. 2572 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2573 << CodeModificationHint::CreateRemoval( 2574 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2575 } else { 2576 // Okay: Add virtual to the method. 2577 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2578 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2579 CurClass->setAggregate(false); 2580 CurClass->setPOD(false); 2581 CurClass->setEmpty(false); 2582 CurClass->setPolymorphic(true); 2583 CurClass->setHasTrivialConstructor(false); 2584 CurClass->setHasTrivialCopyConstructor(false); 2585 CurClass->setHasTrivialCopyAssignment(false); 2586 } 2587 } 2588 2589 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2590 // Look for virtual methods in base classes that this method might override. 2591 2592 BasePaths Paths; 2593 if (LookupInBases(cast<CXXRecordDecl>(DC), 2594 MemberLookupCriteria(NewMD), Paths)) { 2595 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2596 E = Paths.found_decls_end(); I != E; ++I) { 2597 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2598 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2599 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2600 NewMD->addOverriddenMethod(OldMD); 2601 } 2602 } 2603 } 2604 } 2605 2606 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2607 !CurContext->isRecord()) { 2608 // C++ [class.static]p1: 2609 // A data or function member of a class may be declared static 2610 // in a class definition, in which case it is a static member of 2611 // the class. 2612 2613 // Complain about the 'static' specifier if it's on an out-of-line 2614 // member function definition. 2615 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2616 diag::err_static_out_of_line) 2617 << CodeModificationHint::CreateRemoval( 2618 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2619 } 2620 2621 // Handle GNU asm-label extension (encoded as an attribute). 2622 if (Expr *E = (Expr*) D.getAsmLabel()) { 2623 // The parser guarantees this is a string. 2624 StringLiteral *SE = cast<StringLiteral>(E); 2625 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2626 SE->getByteLength()))); 2627 } 2628 2629 // Copy the parameter declarations from the declarator D to the function 2630 // declaration NewFD, if they are available. First scavenge them into Params. 2631 llvm::SmallVector<ParmVarDecl*, 16> Params; 2632 if (D.getNumTypeObjects() > 0) { 2633 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2634 2635 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2636 // function that takes no arguments, not a function that takes a 2637 // single void argument. 2638 // We let through "const void" here because Sema::GetTypeForDeclarator 2639 // already checks for that case. 2640 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2641 FTI.ArgInfo[0].Param && 2642 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2643 // Empty arg list, don't push any params. 2644 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2645 2646 // In C++, the empty parameter-type-list must be spelled "void"; a 2647 // typedef of void is not permitted. 2648 if (getLangOptions().CPlusPlus && 2649 Param->getType().getUnqualifiedType() != Context.VoidTy) 2650 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2651 // FIXME: Leaks decl? 2652 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2653 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2654 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2655 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2656 Param->setDeclContext(NewFD); 2657 Params.push_back(Param); 2658 } 2659 } 2660 2661 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2662 // When we're declaring a function with a typedef, typeof, etc as in the 2663 // following example, we'll need to synthesize (unnamed) 2664 // parameters for use in the declaration. 2665 // 2666 // @code 2667 // typedef void fn(int); 2668 // fn f; 2669 // @endcode 2670 2671 // Synthesize a parameter for each argument type. 2672 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2673 AE = FT->arg_type_end(); AI != AE; ++AI) { 2674 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2675 SourceLocation(), 0, 2676 *AI, /*DInfo=*/0, 2677 VarDecl::None, 0); 2678 Param->setImplicit(); 2679 Params.push_back(Param); 2680 } 2681 } else { 2682 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2683 "Should not need args for typedef of non-prototype fn"); 2684 } 2685 // Finally, we know we have the right number of parameters, install them. 2686 NewFD->setParams(Context, Params.data(), Params.size()); 2687 2688 // If name lookup finds a previous declaration that is not in the 2689 // same scope as the new declaration, this may still be an 2690 // acceptable redeclaration. 2691 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2692 !(NewFD->hasLinkage() && 2693 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2694 PrevDecl = 0; 2695 2696 // FIXME: If the declarator has a template argument list but 2697 // isFunctionTemplateSpecialization is false, this is a function template 2698 // specialization but the user forgot the "template<>" header. Complain about 2699 // the missing template<> header and set isFunctionTemplateSpecialization. 2700 2701 if (isFunctionTemplateSpecialization && 2702 CheckFunctionTemplateSpecialization(NewFD, 2703 /*FIXME:*/false, SourceLocation(), 2704 0, 0, SourceLocation(), 2705 PrevDecl)) 2706 NewFD->setInvalidDecl(); 2707 2708 // Perform semantic checking on the function declaration. 2709 bool OverloadableAttrRequired = false; // FIXME: HACK! 2710 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2711 /*FIXME:*/OverloadableAttrRequired); 2712 2713 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2714 // An out-of-line member function declaration must also be a 2715 // definition (C++ [dcl.meaning]p1). 2716 // FIXME: Find a better way to recognize out-of-line specializations! 2717 if (!IsFunctionDefinition && !isFriend && 2718 !(TemplateParamLists.size() && !FunctionTemplate)) { 2719 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2720 << D.getCXXScopeSpec().getRange(); 2721 NewFD->setInvalidDecl(); 2722 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2723 // The user tried to provide an out-of-line definition for a 2724 // function that is a member of a class or namespace, but there 2725 // was no such member function declared (C++ [class.mfct]p2, 2726 // C++ [namespace.memdef]p2). For example: 2727 // 2728 // class X { 2729 // void f() const; 2730 // }; 2731 // 2732 // void X::f() { } // ill-formed 2733 // 2734 // Complain about this problem, and attempt to suggest close 2735 // matches (e.g., those that differ only in cv-qualifiers and 2736 // whether the parameter types are references). 2737 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2738 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2739 NewFD->setInvalidDecl(); 2740 2741 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2742 true); 2743 assert(!Prev.isAmbiguous() && 2744 "Cannot have an ambiguity in previous-declaration lookup"); 2745 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2746 Func != FuncEnd; ++Func) { 2747 if (isa<FunctionDecl>(*Func) && 2748 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2749 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2750 } 2751 2752 PrevDecl = 0; 2753 } 2754 } 2755 2756 // Handle attributes. We need to have merged decls when handling attributes 2757 // (for example to check for conflicts, etc). 2758 // FIXME: This needs to happen before we merge declarations. Then, 2759 // let attribute merging cope with attribute conflicts. 2760 ProcessDeclAttributes(S, NewFD, D); 2761 2762 // attributes declared post-definition are currently ignored 2763 if (Redeclaration && PrevDecl) { 2764 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2765 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2766 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2767 Diag(Def->getLocation(), diag::note_previous_definition); 2768 } 2769 } 2770 2771 AddKnownFunctionAttributes(NewFD); 2772 2773 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2774 // If a function name is overloadable in C, then every function 2775 // with that name must be marked "overloadable". 2776 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2777 << Redeclaration << NewFD; 2778 if (PrevDecl) 2779 Diag(PrevDecl->getLocation(), 2780 diag::note_attribute_overloadable_prev_overload); 2781 NewFD->addAttr(::new (Context) OverloadableAttr()); 2782 } 2783 2784 // If this is a locally-scoped extern C function, update the 2785 // map of such names. 2786 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2787 && !NewFD->isInvalidDecl()) 2788 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2789 2790 // Set this FunctionDecl's range up to the right paren. 2791 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2792 2793 if (FunctionTemplate && NewFD->isInvalidDecl()) 2794 FunctionTemplate->setInvalidDecl(); 2795 2796 if (FunctionTemplate) 2797 return FunctionTemplate; 2798 2799 return NewFD; 2800} 2801 2802/// \brief Perform semantic checking of a new function declaration. 2803/// 2804/// Performs semantic analysis of the new function declaration 2805/// NewFD. This routine performs all semantic checking that does not 2806/// require the actual declarator involved in the declaration, and is 2807/// used both for the declaration of functions as they are parsed 2808/// (called via ActOnDeclarator) and for the declaration of functions 2809/// that have been instantiated via C++ template instantiation (called 2810/// via InstantiateDecl). 2811/// 2812/// This sets NewFD->isInvalidDecl() to true if there was an error. 2813void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2814 bool &Redeclaration, 2815 bool &OverloadableAttrRequired) { 2816 // If NewFD is already known erroneous, don't do any of this checking. 2817 if (NewFD->isInvalidDecl()) 2818 return; 2819 2820 if (NewFD->getResultType()->isVariablyModifiedType()) { 2821 // Functions returning a variably modified type violate C99 6.7.5.2p2 2822 // because all functions have linkage. 2823 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2824 return NewFD->setInvalidDecl(); 2825 } 2826 2827 if (NewFD->isMain()) 2828 CheckMain(NewFD); 2829 2830 // Check for a previous declaration of this name. 2831 if (!PrevDecl && NewFD->isExternC()) { 2832 // Since we did not find anything by this name and we're declaring 2833 // an extern "C" function, look for a non-visible extern "C" 2834 // declaration with the same name. 2835 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2836 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2837 if (Pos != LocallyScopedExternalDecls.end()) 2838 PrevDecl = Pos->second; 2839 } 2840 2841 // Merge or overload the declaration with an existing declaration of 2842 // the same name, if appropriate. 2843 if (PrevDecl) { 2844 // Determine whether NewFD is an overload of PrevDecl or 2845 // a declaration that requires merging. If it's an overload, 2846 // there's no more work to do here; we'll just add the new 2847 // function to the scope. 2848 OverloadedFunctionDecl::function_iterator MatchedDecl; 2849 2850 if (!getLangOptions().CPlusPlus && 2851 AllowOverloadingOfFunction(PrevDecl, Context)) { 2852 OverloadableAttrRequired = true; 2853 2854 // Functions marked "overloadable" must have a prototype (that 2855 // we can't get through declaration merging). 2856 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2857 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2858 << NewFD; 2859 Redeclaration = true; 2860 2861 // Turn this into a variadic function with no parameters. 2862 QualType R = Context.getFunctionType( 2863 NewFD->getType()->getAs<FunctionType>()->getResultType(), 2864 0, 0, true, 0); 2865 NewFD->setType(R); 2866 return NewFD->setInvalidDecl(); 2867 } 2868 } 2869 2870 if (PrevDecl && 2871 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2872 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2873 Redeclaration = true; 2874 Decl *OldDecl = PrevDecl; 2875 2876 // If PrevDecl was an overloaded function, extract the 2877 // FunctionDecl that matched. 2878 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2879 OldDecl = *MatchedDecl; 2880 2881 // NewFD and OldDecl represent declarations that need to be 2882 // merged. 2883 if (MergeFunctionDecl(NewFD, OldDecl)) 2884 return NewFD->setInvalidDecl(); 2885 2886 if (FunctionTemplateDecl *OldTemplateDecl 2887 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2888 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2889 else { 2890 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2891 NewFD->setAccess(OldDecl->getAccess()); 2892 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2893 } 2894 } 2895 } 2896 2897 // Semantic checking for this function declaration (in isolation). 2898 if (getLangOptions().CPlusPlus) { 2899 // C++-specific checks. 2900 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2901 CheckConstructor(Constructor); 2902 } else if (isa<CXXDestructorDecl>(NewFD)) { 2903 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2904 QualType ClassType = Context.getTypeDeclType(Record); 2905 if (!ClassType->isDependentType()) { 2906 DeclarationName Name 2907 = Context.DeclarationNames.getCXXDestructorName( 2908 Context.getCanonicalType(ClassType)); 2909 if (NewFD->getDeclName() != Name) { 2910 Diag(NewFD->getLocation(), diag::err_destructor_name); 2911 return NewFD->setInvalidDecl(); 2912 } 2913 } 2914 Record->setUserDeclaredDestructor(true); 2915 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2916 // user-defined destructor. 2917 Record->setPOD(false); 2918 2919 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2920 // declared destructor. 2921 // FIXME: C++0x: don't do this for "= default" destructors 2922 Record->setHasTrivialDestructor(false); 2923 } else if (CXXConversionDecl *Conversion 2924 = dyn_cast<CXXConversionDecl>(NewFD)) 2925 ActOnConversionDeclarator(Conversion); 2926 2927 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2928 if (NewFD->isOverloadedOperator() && 2929 CheckOverloadedOperatorDeclaration(NewFD)) 2930 return NewFD->setInvalidDecl(); 2931 2932 // In C++, check default arguments now that we have merged decls. Unless 2933 // the lexical context is the class, because in this case this is done 2934 // during delayed parsing anyway. 2935 if (!CurContext->isRecord()) 2936 CheckCXXDefaultArguments(NewFD); 2937 } 2938} 2939 2940void Sema::CheckMain(FunctionDecl* FD) { 2941 // C++ [basic.start.main]p3: A program that declares main to be inline 2942 // or static is ill-formed. 2943 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2944 // shall not appear in a declaration of main. 2945 // static main is not an error under C99, but we should warn about it. 2946 bool isInline = FD->isInline(); 2947 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2948 if (isInline || isStatic) { 2949 unsigned diagID = diag::warn_unusual_main_decl; 2950 if (isInline || getLangOptions().CPlusPlus) 2951 diagID = diag::err_unusual_main_decl; 2952 2953 int which = isStatic + (isInline << 1) - 1; 2954 Diag(FD->getLocation(), diagID) << which; 2955 } 2956 2957 QualType T = FD->getType(); 2958 assert(T->isFunctionType() && "function decl is not of function type"); 2959 const FunctionType* FT = T->getAs<FunctionType>(); 2960 2961 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2962 // TODO: add a replacement fixit to turn the return type into 'int'. 2963 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2964 FD->setInvalidDecl(true); 2965 } 2966 2967 // Treat protoless main() as nullary. 2968 if (isa<FunctionNoProtoType>(FT)) return; 2969 2970 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2971 unsigned nparams = FTP->getNumArgs(); 2972 assert(FD->getNumParams() == nparams); 2973 2974 if (nparams > 3) { 2975 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2976 FD->setInvalidDecl(true); 2977 nparams = 3; 2978 } 2979 2980 // FIXME: a lot of the following diagnostics would be improved 2981 // if we had some location information about types. 2982 2983 QualType CharPP = 2984 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2985 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2986 2987 for (unsigned i = 0; i < nparams; ++i) { 2988 QualType AT = FTP->getArgType(i); 2989 2990 bool mismatch = true; 2991 2992 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2993 mismatch = false; 2994 else if (Expected[i] == CharPP) { 2995 // As an extension, the following forms are okay: 2996 // char const ** 2997 // char const * const * 2998 // char * const * 2999 3000 QualifierCollector qs; 3001 const PointerType* PT; 3002 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3003 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3004 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3005 qs.removeConst(); 3006 mismatch = !qs.empty(); 3007 } 3008 } 3009 3010 if (mismatch) { 3011 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3012 // TODO: suggest replacing given type with expected type 3013 FD->setInvalidDecl(true); 3014 } 3015 } 3016 3017 if (nparams == 1 && !FD->isInvalidDecl()) { 3018 Diag(FD->getLocation(), diag::warn_main_one_arg); 3019 } 3020} 3021 3022bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3023 // FIXME: Need strict checking. In C89, we need to check for 3024 // any assignment, increment, decrement, function-calls, or 3025 // commas outside of a sizeof. In C99, it's the same list, 3026 // except that the aforementioned are allowed in unevaluated 3027 // expressions. Everything else falls under the 3028 // "may accept other forms of constant expressions" exception. 3029 // (We never end up here for C++, so the constant expression 3030 // rules there don't matter.) 3031 if (Init->isConstantInitializer(Context)) 3032 return false; 3033 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3034 << Init->getSourceRange(); 3035 return true; 3036} 3037 3038void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3039 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3040} 3041 3042/// AddInitializerToDecl - Adds the initializer Init to the 3043/// declaration dcl. If DirectInit is true, this is C++ direct 3044/// initialization rather than copy initialization. 3045void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3046 Decl *RealDecl = dcl.getAs<Decl>(); 3047 // If there is no declaration, there was an error parsing it. Just ignore 3048 // the initializer. 3049 if (RealDecl == 0) 3050 return; 3051 3052 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3053 // With declarators parsed the way they are, the parser cannot 3054 // distinguish between a normal initializer and a pure-specifier. 3055 // Thus this grotesque test. 3056 IntegerLiteral *IL; 3057 Expr *Init = static_cast<Expr *>(init.get()); 3058 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3059 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3060 if (Method->isVirtualAsWritten()) { 3061 Method->setPure(); 3062 3063 // A class is abstract if at least one function is pure virtual. 3064 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3065 } else if (!Method->isInvalidDecl()) { 3066 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3067 << Method->getDeclName() << Init->getSourceRange(); 3068 Method->setInvalidDecl(); 3069 } 3070 } else { 3071 Diag(Method->getLocation(), diag::err_member_function_initialization) 3072 << Method->getDeclName() << Init->getSourceRange(); 3073 Method->setInvalidDecl(); 3074 } 3075 return; 3076 } 3077 3078 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3079 if (!VDecl) { 3080 if (getLangOptions().CPlusPlus && 3081 RealDecl->getLexicalDeclContext()->isRecord() && 3082 isa<NamedDecl>(RealDecl)) 3083 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3084 << cast<NamedDecl>(RealDecl)->getDeclName(); 3085 else 3086 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3087 RealDecl->setInvalidDecl(); 3088 return; 3089 } 3090 3091 if (!VDecl->getType()->isArrayType() && 3092 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3093 diag::err_typecheck_decl_incomplete_type)) { 3094 RealDecl->setInvalidDecl(); 3095 return; 3096 } 3097 3098 const VarDecl *Def = 0; 3099 if (VDecl->getDefinition(Def)) { 3100 Diag(VDecl->getLocation(), diag::err_redefinition) 3101 << VDecl->getDeclName(); 3102 Diag(Def->getLocation(), diag::note_previous_definition); 3103 VDecl->setInvalidDecl(); 3104 return; 3105 } 3106 3107 // Take ownership of the expression, now that we're sure we have somewhere 3108 // to put it. 3109 Expr *Init = init.takeAs<Expr>(); 3110 assert(Init && "missing initializer"); 3111 3112 // Get the decls type and save a reference for later, since 3113 // CheckInitializerTypes may change it. 3114 QualType DclT = VDecl->getType(), SavT = DclT; 3115 if (VDecl->isBlockVarDecl()) { 3116 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3117 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3118 VDecl->setInvalidDecl(); 3119 } else if (!VDecl->isInvalidDecl()) { 3120 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3121 VDecl->getDeclName(), DirectInit)) 3122 VDecl->setInvalidDecl(); 3123 3124 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3125 // Don't check invalid declarations to avoid emitting useless diagnostics. 3126 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3127 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3128 CheckForConstantInitializer(Init, DclT); 3129 } 3130 } 3131 } else if (VDecl->isStaticDataMember() && 3132 VDecl->getLexicalDeclContext()->isRecord()) { 3133 // This is an in-class initialization for a static data member, e.g., 3134 // 3135 // struct S { 3136 // static const int value = 17; 3137 // }; 3138 3139 // Attach the initializer 3140 VDecl->setInit(Context, Init); 3141 3142 // C++ [class.mem]p4: 3143 // A member-declarator can contain a constant-initializer only 3144 // if it declares a static member (9.4) of const integral or 3145 // const enumeration type, see 9.4.2. 3146 QualType T = VDecl->getType(); 3147 if (!T->isDependentType() && 3148 (!Context.getCanonicalType(T).isConstQualified() || 3149 !T->isIntegralType())) { 3150 Diag(VDecl->getLocation(), diag::err_member_initialization) 3151 << VDecl->getDeclName() << Init->getSourceRange(); 3152 VDecl->setInvalidDecl(); 3153 } else { 3154 // C++ [class.static.data]p4: 3155 // If a static data member is of const integral or const 3156 // enumeration type, its declaration in the class definition 3157 // can specify a constant-initializer which shall be an 3158 // integral constant expression (5.19). 3159 if (!Init->isTypeDependent() && 3160 !Init->getType()->isIntegralType()) { 3161 // We have a non-dependent, non-integral or enumeration type. 3162 Diag(Init->getSourceRange().getBegin(), 3163 diag::err_in_class_initializer_non_integral_type) 3164 << Init->getType() << Init->getSourceRange(); 3165 VDecl->setInvalidDecl(); 3166 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3167 // Check whether the expression is a constant expression. 3168 llvm::APSInt Value; 3169 SourceLocation Loc; 3170 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3171 Diag(Loc, diag::err_in_class_initializer_non_constant) 3172 << Init->getSourceRange(); 3173 VDecl->setInvalidDecl(); 3174 } else if (!VDecl->getType()->isDependentType()) 3175 ImpCastExprToType(Init, VDecl->getType()); 3176 } 3177 } 3178 } else if (VDecl->isFileVarDecl()) { 3179 if (VDecl->getStorageClass() == VarDecl::Extern) 3180 Diag(VDecl->getLocation(), diag::warn_extern_init); 3181 if (!VDecl->isInvalidDecl()) 3182 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3183 VDecl->getDeclName(), DirectInit)) 3184 VDecl->setInvalidDecl(); 3185 3186 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3187 // Don't check invalid declarations to avoid emitting useless diagnostics. 3188 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3189 // C99 6.7.8p4. All file scoped initializers need to be constant. 3190 CheckForConstantInitializer(Init, DclT); 3191 } 3192 } 3193 // If the type changed, it means we had an incomplete type that was 3194 // completed by the initializer. For example: 3195 // int ary[] = { 1, 3, 5 }; 3196 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3197 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3198 VDecl->setType(DclT); 3199 Init->setType(DclT); 3200 } 3201 3202 Init = MaybeCreateCXXExprWithTemporaries(Init, 3203 /*ShouldDestroyTemporaries=*/true); 3204 // Attach the initializer to the decl. 3205 VDecl->setInit(Context, Init); 3206 3207 // If the previous declaration of VDecl was a tentative definition, 3208 // remove it from the set of tentative definitions. 3209 if (VDecl->getPreviousDeclaration() && 3210 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3211 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3212 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3213 } 3214 3215 return; 3216} 3217 3218void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3219 bool TypeContainsUndeducedAuto) { 3220 Decl *RealDecl = dcl.getAs<Decl>(); 3221 3222 // If there is no declaration, there was an error parsing it. Just ignore it. 3223 if (RealDecl == 0) 3224 return; 3225 3226 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3227 QualType Type = Var->getType(); 3228 3229 // Record tentative definitions. 3230 if (Var->isTentativeDefinition(Context)) { 3231 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3232 InsertPair = 3233 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3234 3235 // Keep the latest definition in the map. If we see 'int i; int i;' we 3236 // want the second one in the map. 3237 InsertPair.first->second = Var; 3238 3239 // However, for the list, we don't care about the order, just make sure 3240 // that there are no dupes for a given declaration name. 3241 if (InsertPair.second) 3242 TentativeDefinitionList.push_back(Var->getDeclName()); 3243 } 3244 3245 // C++ [dcl.init.ref]p3: 3246 // The initializer can be omitted for a reference only in a 3247 // parameter declaration (8.3.5), in the declaration of a 3248 // function return type, in the declaration of a class member 3249 // within its class declaration (9.2), and where the extern 3250 // specifier is explicitly used. 3251 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3252 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3253 << Var->getDeclName() 3254 << SourceRange(Var->getLocation(), Var->getLocation()); 3255 Var->setInvalidDecl(); 3256 return; 3257 } 3258 3259 // C++0x [dcl.spec.auto]p3 3260 if (TypeContainsUndeducedAuto) { 3261 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3262 << Var->getDeclName() << Type; 3263 Var->setInvalidDecl(); 3264 return; 3265 } 3266 3267 // C++ [dcl.init]p9: 3268 // If no initializer is specified for an object, and the object 3269 // is of (possibly cv-qualified) non-POD class type (or array 3270 // thereof), the object shall be default-initialized; if the 3271 // object is of const-qualified type, the underlying class type 3272 // shall have a user-declared default constructor. 3273 // 3274 // FIXME: Diagnose the "user-declared default constructor" bit. 3275 if (getLangOptions().CPlusPlus) { 3276 QualType InitType = Type; 3277 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3278 InitType = Array->getElementType(); 3279 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3280 InitType->isRecordType() && !InitType->isDependentType()) { 3281 if (!RequireCompleteType(Var->getLocation(), InitType, 3282 diag::err_invalid_incomplete_type_use)) { 3283 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3284 3285 CXXConstructorDecl *Constructor 3286 = PerformInitializationByConstructor(InitType, 3287 MultiExprArg(*this, 0, 0), 3288 Var->getLocation(), 3289 SourceRange(Var->getLocation(), 3290 Var->getLocation()), 3291 Var->getDeclName(), 3292 IK_Default, 3293 ConstructorArgs); 3294 3295 // FIXME: Location info for the variable initialization? 3296 if (!Constructor) 3297 Var->setInvalidDecl(); 3298 else { 3299 // FIXME: Cope with initialization of arrays 3300 if (!Constructor->isTrivial() && 3301 InitializeVarWithConstructor(Var, Constructor, InitType, 3302 move_arg(ConstructorArgs))) 3303 Var->setInvalidDecl(); 3304 3305 FinalizeVarWithDestructor(Var, InitType); 3306 } 3307 } 3308 } 3309 } 3310 3311#if 0 3312 // FIXME: Temporarily disabled because we are not properly parsing 3313 // linkage specifications on declarations, e.g., 3314 // 3315 // extern "C" const CGPoint CGPointerZero; 3316 // 3317 // C++ [dcl.init]p9: 3318 // 3319 // If no initializer is specified for an object, and the 3320 // object is of (possibly cv-qualified) non-POD class type (or 3321 // array thereof), the object shall be default-initialized; if 3322 // the object is of const-qualified type, the underlying class 3323 // type shall have a user-declared default 3324 // constructor. Otherwise, if no initializer is specified for 3325 // an object, the object and its subobjects, if any, have an 3326 // indeterminate initial value; if the object or any of its 3327 // subobjects are of const-qualified type, the program is 3328 // ill-formed. 3329 // 3330 // This isn't technically an error in C, so we don't diagnose it. 3331 // 3332 // FIXME: Actually perform the POD/user-defined default 3333 // constructor check. 3334 if (getLangOptions().CPlusPlus && 3335 Context.getCanonicalType(Type).isConstQualified() && 3336 !Var->hasExternalStorage()) 3337 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3338 << Var->getName() 3339 << SourceRange(Var->getLocation(), Var->getLocation()); 3340#endif 3341 } 3342} 3343 3344Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3345 DeclPtrTy *Group, 3346 unsigned NumDecls) { 3347 llvm::SmallVector<Decl*, 8> Decls; 3348 3349 if (DS.isTypeSpecOwned()) 3350 Decls.push_back((Decl*)DS.getTypeRep()); 3351 3352 for (unsigned i = 0; i != NumDecls; ++i) 3353 if (Decl *D = Group[i].getAs<Decl>()) 3354 Decls.push_back(D); 3355 3356 // Perform semantic analysis that depends on having fully processed both 3357 // the declarator and initializer. 3358 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3359 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3360 if (!IDecl) 3361 continue; 3362 QualType T = IDecl->getType(); 3363 3364 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3365 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3366 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3367 if (!IDecl->isInvalidDecl() && 3368 RequireCompleteType(IDecl->getLocation(), T, 3369 diag::err_typecheck_decl_incomplete_type)) 3370 IDecl->setInvalidDecl(); 3371 } 3372 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3373 // object that has file scope without an initializer, and without a 3374 // storage-class specifier or with the storage-class specifier "static", 3375 // constitutes a tentative definition. Note: A tentative definition with 3376 // external linkage is valid (C99 6.2.2p5). 3377 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3378 if (const IncompleteArrayType *ArrayT 3379 = Context.getAsIncompleteArrayType(T)) { 3380 if (RequireCompleteType(IDecl->getLocation(), 3381 ArrayT->getElementType(), 3382 diag::err_illegal_decl_array_incomplete_type)) 3383 IDecl->setInvalidDecl(); 3384 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3385 // C99 6.9.2p3: If the declaration of an identifier for an object is 3386 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3387 // declared type shall not be an incomplete type. 3388 // NOTE: code such as the following 3389 // static struct s; 3390 // struct s { int a; }; 3391 // is accepted by gcc. Hence here we issue a warning instead of 3392 // an error and we do not invalidate the static declaration. 3393 // NOTE: to avoid multiple warnings, only check the first declaration. 3394 if (IDecl->getPreviousDeclaration() == 0) 3395 RequireCompleteType(IDecl->getLocation(), T, 3396 diag::ext_typecheck_decl_incomplete_type); 3397 } 3398 } 3399 } 3400 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3401 Decls.data(), Decls.size())); 3402} 3403 3404 3405/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3406/// to introduce parameters into function prototype scope. 3407Sema::DeclPtrTy 3408Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3409 const DeclSpec &DS = D.getDeclSpec(); 3410 3411 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3412 VarDecl::StorageClass StorageClass = VarDecl::None; 3413 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3414 StorageClass = VarDecl::Register; 3415 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3416 Diag(DS.getStorageClassSpecLoc(), 3417 diag::err_invalid_storage_class_in_func_decl); 3418 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3419 } 3420 3421 if (D.getDeclSpec().isThreadSpecified()) 3422 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3423 3424 DiagnoseFunctionSpecifiers(D); 3425 3426 // Check that there are no default arguments inside the type of this 3427 // parameter (C++ only). 3428 if (getLangOptions().CPlusPlus) 3429 CheckExtraCXXDefaultArguments(D); 3430 3431 DeclaratorInfo *DInfo = 0; 3432 TagDecl *OwnedDecl = 0; 3433 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3434 &OwnedDecl); 3435 3436 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3437 // C++ [dcl.fct]p6: 3438 // Types shall not be defined in return or parameter types. 3439 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3440 << Context.getTypeDeclType(OwnedDecl); 3441 } 3442 3443 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3444 // Can this happen for params? We already checked that they don't conflict 3445 // among each other. Here they can only shadow globals, which is ok. 3446 IdentifierInfo *II = D.getIdentifier(); 3447 if (II) { 3448 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3449 if (PrevDecl->isTemplateParameter()) { 3450 // Maybe we will complain about the shadowed template parameter. 3451 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3452 // Just pretend that we didn't see the previous declaration. 3453 PrevDecl = 0; 3454 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3455 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3456 3457 // Recover by removing the name 3458 II = 0; 3459 D.SetIdentifier(0, D.getIdentifierLoc()); 3460 } 3461 } 3462 } 3463 3464 // Parameters can not be abstract class types. 3465 // For record types, this is done by the AbstractClassUsageDiagnoser once 3466 // the class has been completely parsed. 3467 if (!CurContext->isRecord() && 3468 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3469 diag::err_abstract_type_in_decl, 3470 AbstractParamType)) 3471 D.setInvalidType(true); 3472 3473 QualType T = adjustParameterType(parmDeclType); 3474 3475 ParmVarDecl *New; 3476 if (T == parmDeclType) // parameter type did not need adjustment 3477 New = ParmVarDecl::Create(Context, CurContext, 3478 D.getIdentifierLoc(), II, 3479 parmDeclType, DInfo, StorageClass, 3480 0); 3481 else // keep track of both the adjusted and unadjusted types 3482 New = OriginalParmVarDecl::Create(Context, CurContext, 3483 D.getIdentifierLoc(), II, T, DInfo, 3484 parmDeclType, StorageClass, 0); 3485 3486 if (D.isInvalidType()) 3487 New->setInvalidDecl(); 3488 3489 // Parameter declarators cannot be interface types. All ObjC objects are 3490 // passed by reference. 3491 if (T->isObjCInterfaceType()) { 3492 Diag(D.getIdentifierLoc(), 3493 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3494 New->setInvalidDecl(); 3495 } 3496 3497 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3498 if (D.getCXXScopeSpec().isSet()) { 3499 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3500 << D.getCXXScopeSpec().getRange(); 3501 New->setInvalidDecl(); 3502 } 3503 3504 // Add the parameter declaration into this scope. 3505 S->AddDecl(DeclPtrTy::make(New)); 3506 if (II) 3507 IdResolver.AddDecl(New); 3508 3509 ProcessDeclAttributes(S, New, D); 3510 3511 if (New->hasAttr<BlocksAttr>()) { 3512 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3513 } 3514 return DeclPtrTy::make(New); 3515} 3516 3517void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3518 SourceLocation LocAfterDecls) { 3519 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3520 "Not a function declarator!"); 3521 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3522 3523 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3524 // for a K&R function. 3525 if (!FTI.hasPrototype) { 3526 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3527 --i; 3528 if (FTI.ArgInfo[i].Param == 0) { 3529 std::string Code = " int "; 3530 Code += FTI.ArgInfo[i].Ident->getName(); 3531 Code += ";\n"; 3532 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3533 << FTI.ArgInfo[i].Ident 3534 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3535 3536 // Implicitly declare the argument as type 'int' for lack of a better 3537 // type. 3538 DeclSpec DS; 3539 const char* PrevSpec; // unused 3540 unsigned DiagID; // unused 3541 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3542 PrevSpec, DiagID); 3543 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3544 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3545 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3546 } 3547 } 3548 } 3549} 3550 3551Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3552 Declarator &D) { 3553 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3554 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3555 "Not a function declarator!"); 3556 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3557 3558 if (FTI.hasPrototype) { 3559 // FIXME: Diagnose arguments without names in C. 3560 } 3561 3562 Scope *ParentScope = FnBodyScope->getParent(); 3563 3564 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3565 MultiTemplateParamsArg(*this), 3566 /*IsFunctionDefinition=*/true); 3567 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3568} 3569 3570Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3571 if (!D) 3572 return D; 3573 FunctionDecl *FD = 0; 3574 3575 if (FunctionTemplateDecl *FunTmpl 3576 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3577 FD = FunTmpl->getTemplatedDecl(); 3578 else 3579 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3580 3581 CurFunctionNeedsScopeChecking = false; 3582 3583 // See if this is a redefinition. 3584 const FunctionDecl *Definition; 3585 if (FD->getBody(Definition)) { 3586 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3587 Diag(Definition->getLocation(), diag::note_previous_definition); 3588 } 3589 3590 // Builtin functions cannot be defined. 3591 if (unsigned BuiltinID = FD->getBuiltinID()) { 3592 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3593 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3594 FD->setInvalidDecl(); 3595 } 3596 } 3597 3598 // The return type of a function definition must be complete 3599 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3600 QualType ResultType = FD->getResultType(); 3601 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3602 !FD->isInvalidDecl() && 3603 RequireCompleteType(FD->getLocation(), ResultType, 3604 diag::err_func_def_incomplete_result)) 3605 FD->setInvalidDecl(); 3606 3607 // GNU warning -Wmissing-prototypes: 3608 // Warn if a global function is defined without a previous 3609 // prototype declaration. This warning is issued even if the 3610 // definition itself provides a prototype. The aim is to detect 3611 // global functions that fail to be declared in header files. 3612 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3613 !FD->isMain()) { 3614 bool MissingPrototype = true; 3615 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3616 Prev; Prev = Prev->getPreviousDeclaration()) { 3617 // Ignore any declarations that occur in function or method 3618 // scope, because they aren't visible from the header. 3619 if (Prev->getDeclContext()->isFunctionOrMethod()) 3620 continue; 3621 3622 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3623 break; 3624 } 3625 3626 if (MissingPrototype) 3627 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3628 } 3629 3630 if (FnBodyScope) 3631 PushDeclContext(FnBodyScope, FD); 3632 3633 // Check the validity of our function parameters 3634 CheckParmsForFunctionDef(FD); 3635 3636 // Introduce our parameters into the function scope 3637 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3638 ParmVarDecl *Param = FD->getParamDecl(p); 3639 Param->setOwningFunction(FD); 3640 3641 // If this has an identifier, add it to the scope stack. 3642 if (Param->getIdentifier() && FnBodyScope) 3643 PushOnScopeChains(Param, FnBodyScope); 3644 } 3645 3646 // Checking attributes of current function definition 3647 // dllimport attribute. 3648 if (FD->getAttr<DLLImportAttr>() && 3649 (!FD->getAttr<DLLExportAttr>())) { 3650 // dllimport attribute cannot be applied to definition. 3651 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3652 Diag(FD->getLocation(), 3653 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3654 << "dllimport"; 3655 FD->setInvalidDecl(); 3656 return DeclPtrTy::make(FD); 3657 } else { 3658 // If a symbol previously declared dllimport is later defined, the 3659 // attribute is ignored in subsequent references, and a warning is 3660 // emitted. 3661 Diag(FD->getLocation(), 3662 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3663 << FD->getNameAsCString() << "dllimport"; 3664 } 3665 } 3666 return DeclPtrTy::make(FD); 3667} 3668 3669Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3670 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3671} 3672 3673Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3674 bool IsInstantiation) { 3675 Decl *dcl = D.getAs<Decl>(); 3676 Stmt *Body = BodyArg.takeAs<Stmt>(); 3677 3678 FunctionDecl *FD = 0; 3679 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3680 if (FunTmpl) 3681 FD = FunTmpl->getTemplatedDecl(); 3682 else 3683 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3684 3685 if (FD) { 3686 FD->setBody(Body); 3687 if (FD->isMain()) 3688 // C and C++ allow for main to automagically return 0. 3689 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3690 FD->setHasImplicitReturnZero(true); 3691 else 3692 CheckFallThroughForFunctionDef(FD, Body); 3693 3694 if (!FD->isInvalidDecl()) 3695 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3696 3697 // C++ [basic.def.odr]p2: 3698 // [...] A virtual member function is used if it is not pure. [...] 3699 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3700 if (Method->isVirtual() && !Method->isPure()) 3701 MarkDeclarationReferenced(Method->getLocation(), Method); 3702 3703 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3704 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3705 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3706 MD->setBody(Body); 3707 CheckFallThroughForFunctionDef(MD, Body); 3708 MD->setEndLoc(Body->getLocEnd()); 3709 3710 if (!MD->isInvalidDecl()) 3711 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3712 } else { 3713 Body->Destroy(Context); 3714 return DeclPtrTy(); 3715 } 3716 if (!IsInstantiation) 3717 PopDeclContext(); 3718 3719 // Verify and clean out per-function state. 3720 3721 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3722 3723 // Check goto/label use. 3724 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3725 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3726 LabelStmt *L = I->second; 3727 3728 // Verify that we have no forward references left. If so, there was a goto 3729 // or address of a label taken, but no definition of it. Label fwd 3730 // definitions are indicated with a null substmt. 3731 if (L->getSubStmt() != 0) 3732 continue; 3733 3734 // Emit error. 3735 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3736 3737 // At this point, we have gotos that use the bogus label. Stitch it into 3738 // the function body so that they aren't leaked and that the AST is well 3739 // formed. 3740 if (Body == 0) { 3741 // The whole function wasn't parsed correctly, just delete this. 3742 L->Destroy(Context); 3743 continue; 3744 } 3745 3746 // Otherwise, the body is valid: we want to stitch the label decl into the 3747 // function somewhere so that it is properly owned and so that the goto 3748 // has a valid target. Do this by creating a new compound stmt with the 3749 // label in it. 3750 3751 // Give the label a sub-statement. 3752 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3753 3754 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3755 cast<CXXTryStmt>(Body)->getTryBlock() : 3756 cast<CompoundStmt>(Body); 3757 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3758 Elements.push_back(L); 3759 Compound->setStmts(Context, &Elements[0], Elements.size()); 3760 } 3761 FunctionLabelMap.clear(); 3762 3763 if (!Body) return D; 3764 3765 // Verify that that gotos and switch cases don't jump into scopes illegally. 3766 if (CurFunctionNeedsScopeChecking) 3767 DiagnoseInvalidJumps(Body); 3768 3769 // C++ constructors that have function-try-blocks can't have return 3770 // statements in the handlers of that block. (C++ [except.handle]p14) 3771 // Verify this. 3772 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3773 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3774 3775 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3776 computeBaseOrMembersToDestroy(Destructor); 3777 return D; 3778} 3779 3780/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3781/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3782NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3783 IdentifierInfo &II, Scope *S) { 3784 // Before we produce a declaration for an implicitly defined 3785 // function, see whether there was a locally-scoped declaration of 3786 // this name as a function or variable. If so, use that 3787 // (non-visible) declaration, and complain about it. 3788 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3789 = LocallyScopedExternalDecls.find(&II); 3790 if (Pos != LocallyScopedExternalDecls.end()) { 3791 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3792 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3793 return Pos->second; 3794 } 3795 3796 // Extension in C99. Legal in C90, but warn about it. 3797 if (getLangOptions().C99) 3798 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3799 else 3800 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3801 3802 // FIXME: handle stuff like: 3803 // void foo() { extern float X(); } 3804 // void bar() { X(); } <-- implicit decl for X in another scope. 3805 3806 // Set a Declarator for the implicit definition: int foo(); 3807 const char *Dummy; 3808 DeclSpec DS; 3809 unsigned DiagID; 3810 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3811 Error = Error; // Silence warning. 3812 assert(!Error && "Error setting up implicit decl!"); 3813 Declarator D(DS, Declarator::BlockContext); 3814 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3815 0, 0, false, SourceLocation(), 3816 false, 0,0,0, Loc, Loc, D), 3817 SourceLocation()); 3818 D.SetIdentifier(&II, Loc); 3819 3820 // Insert this function into translation-unit scope. 3821 3822 DeclContext *PrevDC = CurContext; 3823 CurContext = Context.getTranslationUnitDecl(); 3824 3825 FunctionDecl *FD = 3826 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3827 FD->setImplicit(); 3828 3829 CurContext = PrevDC; 3830 3831 AddKnownFunctionAttributes(FD); 3832 3833 return FD; 3834} 3835 3836/// \brief Adds any function attributes that we know a priori based on 3837/// the declaration of this function. 3838/// 3839/// These attributes can apply both to implicitly-declared builtins 3840/// (like __builtin___printf_chk) or to library-declared functions 3841/// like NSLog or printf. 3842void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3843 if (FD->isInvalidDecl()) 3844 return; 3845 3846 // If this is a built-in function, map its builtin attributes to 3847 // actual attributes. 3848 if (unsigned BuiltinID = FD->getBuiltinID()) { 3849 // Handle printf-formatting attributes. 3850 unsigned FormatIdx; 3851 bool HasVAListArg; 3852 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3853 if (!FD->getAttr<FormatAttr>()) 3854 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3855 HasVAListArg ? 0 : FormatIdx + 2)); 3856 } 3857 3858 // Mark const if we don't care about errno and that is the only 3859 // thing preventing the function from being const. This allows 3860 // IRgen to use LLVM intrinsics for such functions. 3861 if (!getLangOptions().MathErrno && 3862 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3863 if (!FD->getAttr<ConstAttr>()) 3864 FD->addAttr(::new (Context) ConstAttr()); 3865 } 3866 3867 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3868 FD->addAttr(::new (Context) NoReturnAttr()); 3869 } 3870 3871 IdentifierInfo *Name = FD->getIdentifier(); 3872 if (!Name) 3873 return; 3874 if ((!getLangOptions().CPlusPlus && 3875 FD->getDeclContext()->isTranslationUnit()) || 3876 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3877 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3878 LinkageSpecDecl::lang_c)) { 3879 // Okay: this could be a libc/libm/Objective-C function we know 3880 // about. 3881 } else 3882 return; 3883 3884 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3885 // FIXME: NSLog and NSLogv should be target specific 3886 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3887 // FIXME: We known better than our headers. 3888 const_cast<FormatAttr *>(Format)->setType("printf"); 3889 } else 3890 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3891 Name->isStr("NSLogv") ? 0 : 2)); 3892 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3893 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3894 // target-specific builtins, perhaps? 3895 if (!FD->getAttr<FormatAttr>()) 3896 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3897 Name->isStr("vasprintf") ? 0 : 3)); 3898 } 3899} 3900 3901TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3902 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3903 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3904 3905 // Scope manipulation handled by caller. 3906 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3907 D.getIdentifierLoc(), 3908 D.getIdentifier(), 3909 T); 3910 3911 if (const TagType *TT = T->getAs<TagType>()) { 3912 TagDecl *TD = TT->getDecl(); 3913 3914 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3915 // keep track of the TypedefDecl. 3916 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3917 TD->setTypedefForAnonDecl(NewTD); 3918 } 3919 3920 if (D.isInvalidType()) 3921 NewTD->setInvalidDecl(); 3922 return NewTD; 3923} 3924 3925 3926/// \brief Determine whether a tag with a given kind is acceptable 3927/// as a redeclaration of the given tag declaration. 3928/// 3929/// \returns true if the new tag kind is acceptable, false otherwise. 3930bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3931 TagDecl::TagKind NewTag, 3932 SourceLocation NewTagLoc, 3933 const IdentifierInfo &Name) { 3934 // C++ [dcl.type.elab]p3: 3935 // The class-key or enum keyword present in the 3936 // elaborated-type-specifier shall agree in kind with the 3937 // declaration to which the name in theelaborated-type-specifier 3938 // refers. This rule also applies to the form of 3939 // elaborated-type-specifier that declares a class-name or 3940 // friend class since it can be construed as referring to the 3941 // definition of the class. Thus, in any 3942 // elaborated-type-specifier, the enum keyword shall be used to 3943 // refer to an enumeration (7.2), the union class-keyshall be 3944 // used to refer to a union (clause 9), and either the class or 3945 // struct class-key shall be used to refer to a class (clause 9) 3946 // declared using the class or struct class-key. 3947 TagDecl::TagKind OldTag = Previous->getTagKind(); 3948 if (OldTag == NewTag) 3949 return true; 3950 3951 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3952 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3953 // Warn about the struct/class tag mismatch. 3954 bool isTemplate = false; 3955 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3956 isTemplate = Record->getDescribedClassTemplate(); 3957 3958 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3959 << (NewTag == TagDecl::TK_class) 3960 << isTemplate << &Name 3961 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3962 OldTag == TagDecl::TK_class? "class" : "struct"); 3963 Diag(Previous->getLocation(), diag::note_previous_use); 3964 return true; 3965 } 3966 return false; 3967} 3968 3969/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3970/// former case, Name will be non-null. In the later case, Name will be null. 3971/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3972/// reference/declaration/definition of a tag. 3973Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3974 SourceLocation KWLoc, const CXXScopeSpec &SS, 3975 IdentifierInfo *Name, SourceLocation NameLoc, 3976 AttributeList *Attr, AccessSpecifier AS, 3977 MultiTemplateParamsArg TemplateParameterLists, 3978 bool &OwnedDecl, bool &IsDependent) { 3979 // If this is not a definition, it must have a name. 3980 assert((Name != 0 || TUK == TUK_Definition) && 3981 "Nameless record must be a definition!"); 3982 3983 OwnedDecl = false; 3984 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 3985 3986 if (TUK != TUK_Reference) { 3987 if (TemplateParameterList *TemplateParams 3988 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3989 (TemplateParameterList**)TemplateParameterLists.get(), 3990 TemplateParameterLists.size())) { 3991 if (TUK == TUK_Friend) { 3992 // When declaring a friend template, we do want to match the 3993 // template parameters to the scope specifier, but don't go so far 3994 // as to try to declare a new template. 3995 } else if (TemplateParams->size() > 0) { 3996 // This is a declaration or definition of a class template (which may 3997 // be a member of another template). 3998 OwnedDecl = false; 3999 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4000 SS, Name, NameLoc, Attr, 4001 TemplateParams, 4002 AS); 4003 TemplateParameterLists.release(); 4004 return Result.get(); 4005 } else { 4006 // FIXME: diagnose the extraneous 'template<>', once we recover 4007 // slightly better in ParseTemplate.cpp from bogus template 4008 // parameters. 4009 } 4010 } 4011 } 4012 4013 DeclContext *SearchDC = CurContext; 4014 DeclContext *DC = CurContext; 4015 NamedDecl *PrevDecl = 0; 4016 bool isStdBadAlloc = false; 4017 bool Invalid = false; 4018 4019 if (Name && SS.isNotEmpty()) { 4020 // We have a nested-name tag ('struct foo::bar'). 4021 4022 // Check for invalid 'foo::'. 4023 if (SS.isInvalid()) { 4024 Name = 0; 4025 goto CreateNewDecl; 4026 } 4027 4028 // If this is a friend or a reference to a class in a dependent 4029 // context, don't try to make a decl for it. 4030 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4031 DC = computeDeclContext(SS, false); 4032 if (!DC) { 4033 IsDependent = true; 4034 return DeclPtrTy(); 4035 } 4036 } 4037 4038 if (RequireCompleteDeclContext(SS)) 4039 return DeclPtrTy::make((Decl *)0); 4040 4041 DC = computeDeclContext(SS, true); 4042 SearchDC = DC; 4043 // Look-up name inside 'foo::'. 4044 PrevDecl 4045 = dyn_cast_or_null<TagDecl>( 4046 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4047 4048 // A tag 'foo::bar' must already exist. 4049 if (PrevDecl == 0) { 4050 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4051 Name = 0; 4052 Invalid = true; 4053 goto CreateNewDecl; 4054 } 4055 } else if (Name) { 4056 // If this is a named struct, check to see if there was a previous forward 4057 // declaration or definition. 4058 // FIXME: We're looking into outer scopes here, even when we 4059 // shouldn't be. Doing so can result in ambiguities that we 4060 // shouldn't be diagnosing. 4061 LookupResult R = LookupName(S, Name, LookupTagName, 4062 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4063 if (R.isAmbiguous()) { 4064 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4065 // FIXME: This is not best way to recover from case like: 4066 // 4067 // struct S s; 4068 // 4069 // causes needless "incomplete type" error later. 4070 Name = 0; 4071 PrevDecl = 0; 4072 Invalid = true; 4073 } else 4074 PrevDecl = R; 4075 4076 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4077 // FIXME: This makes sure that we ignore the contexts associated 4078 // with C structs, unions, and enums when looking for a matching 4079 // tag declaration or definition. See the similar lookup tweak 4080 // in Sema::LookupName; is there a better way to deal with this? 4081 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4082 SearchDC = SearchDC->getParent(); 4083 } 4084 } 4085 4086 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4087 // Maybe we will complain about the shadowed template parameter. 4088 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4089 // Just pretend that we didn't see the previous declaration. 4090 PrevDecl = 0; 4091 } 4092 4093 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4094 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4095 // This is a declaration of or a reference to "std::bad_alloc". 4096 isStdBadAlloc = true; 4097 4098 if (!PrevDecl && StdBadAlloc) { 4099 // std::bad_alloc has been implicitly declared (but made invisible to 4100 // name lookup). Fill in this implicit declaration as the previous 4101 // declaration, so that the declarations get chained appropriately. 4102 PrevDecl = StdBadAlloc; 4103 } 4104 } 4105 4106 if (PrevDecl) { 4107 // Check whether the previous declaration is usable. 4108 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4109 4110 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4111 // If this is a use of a previous tag, or if the tag is already declared 4112 // in the same scope (so that the definition/declaration completes or 4113 // rementions the tag), reuse the decl. 4114 if (TUK == TUK_Reference || TUK == TUK_Friend || 4115 isDeclInScope(PrevDecl, SearchDC, S)) { 4116 // Make sure that this wasn't declared as an enum and now used as a 4117 // struct or something similar. 4118 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4119 bool SafeToContinue 4120 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4121 Kind != TagDecl::TK_enum); 4122 if (SafeToContinue) 4123 Diag(KWLoc, diag::err_use_with_wrong_tag) 4124 << Name 4125 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4126 PrevTagDecl->getKindName()); 4127 else 4128 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4129 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4130 4131 if (SafeToContinue) 4132 Kind = PrevTagDecl->getTagKind(); 4133 else { 4134 // Recover by making this an anonymous redefinition. 4135 Name = 0; 4136 PrevDecl = 0; 4137 Invalid = true; 4138 } 4139 } 4140 4141 if (!Invalid) { 4142 // If this is a use, just return the declaration we found. 4143 4144 // FIXME: In the future, return a variant or some other clue 4145 // for the consumer of this Decl to know it doesn't own it. 4146 // For our current ASTs this shouldn't be a problem, but will 4147 // need to be changed with DeclGroups. 4148 if (TUK == TUK_Reference) 4149 return DeclPtrTy::make(PrevDecl); 4150 4151 // If this is a friend, make sure we create the new 4152 // declaration in the appropriate semantic context. 4153 if (TUK == TUK_Friend) 4154 SearchDC = PrevDecl->getDeclContext(); 4155 4156 // Diagnose attempts to redefine a tag. 4157 if (TUK == TUK_Definition) { 4158 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4159 Diag(NameLoc, diag::err_redefinition) << Name; 4160 Diag(Def->getLocation(), diag::note_previous_definition); 4161 // If this is a redefinition, recover by making this 4162 // struct be anonymous, which will make any later 4163 // references get the previous definition. 4164 Name = 0; 4165 PrevDecl = 0; 4166 Invalid = true; 4167 } else { 4168 // If the type is currently being defined, complain 4169 // about a nested redefinition. 4170 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4171 if (Tag->isBeingDefined()) { 4172 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4173 Diag(PrevTagDecl->getLocation(), 4174 diag::note_previous_definition); 4175 Name = 0; 4176 PrevDecl = 0; 4177 Invalid = true; 4178 } 4179 } 4180 4181 // Okay, this is definition of a previously declared or referenced 4182 // tag PrevDecl. We're going to create a new Decl for it. 4183 } 4184 } 4185 // If we get here we have (another) forward declaration or we 4186 // have a definition. Just create a new decl. 4187 4188 } else { 4189 // If we get here, this is a definition of a new tag type in a nested 4190 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4191 // new decl/type. We set PrevDecl to NULL so that the entities 4192 // have distinct types. 4193 PrevDecl = 0; 4194 } 4195 // If we get here, we're going to create a new Decl. If PrevDecl 4196 // is non-NULL, it's a definition of the tag declared by 4197 // PrevDecl. If it's NULL, we have a new definition. 4198 } else { 4199 // PrevDecl is a namespace, template, or anything else 4200 // that lives in the IDNS_Tag identifier namespace. 4201 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4202 // The tag name clashes with a namespace name, issue an error and 4203 // recover by making this tag be anonymous. 4204 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4205 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4206 Name = 0; 4207 PrevDecl = 0; 4208 Invalid = true; 4209 } else { 4210 // The existing declaration isn't relevant to us; we're in a 4211 // new scope, so clear out the previous declaration. 4212 PrevDecl = 0; 4213 } 4214 } 4215 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4216 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4217 // C++ [basic.scope.pdecl]p5: 4218 // -- for an elaborated-type-specifier of the form 4219 // 4220 // class-key identifier 4221 // 4222 // if the elaborated-type-specifier is used in the 4223 // decl-specifier-seq or parameter-declaration-clause of a 4224 // function defined in namespace scope, the identifier is 4225 // declared as a class-name in the namespace that contains 4226 // the declaration; otherwise, except as a friend 4227 // declaration, the identifier is declared in the smallest 4228 // non-class, non-function-prototype scope that contains the 4229 // declaration. 4230 // 4231 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4232 // C structs and unions. 4233 // 4234 // GNU C also supports this behavior as part of its incomplete 4235 // enum types extension, while GNU C++ does not. 4236 // 4237 // Find the context where we'll be declaring the tag. 4238 // FIXME: We would like to maintain the current DeclContext as the 4239 // lexical context, 4240 while (SearchDC->isRecord()) 4241 SearchDC = SearchDC->getParent(); 4242 4243 // Find the scope where we'll be declaring the tag. 4244 while (S->isClassScope() || 4245 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4246 ((S->getFlags() & Scope::DeclScope) == 0) || 4247 (S->getEntity() && 4248 ((DeclContext *)S->getEntity())->isTransparentContext())) 4249 S = S->getParent(); 4250 4251 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4252 // C++ [namespace.memdef]p3: 4253 // If a friend declaration in a non-local class first declares a 4254 // class or function, the friend class or function is a member of 4255 // the innermost enclosing namespace. 4256 while (!SearchDC->isFileContext()) 4257 SearchDC = SearchDC->getParent(); 4258 4259 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4260 while (S->getEntity() != SearchDC) 4261 S = S->getParent(); 4262 } 4263 4264CreateNewDecl: 4265 4266 // If there is an identifier, use the location of the identifier as the 4267 // location of the decl, otherwise use the location of the struct/union 4268 // keyword. 4269 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4270 4271 // Otherwise, create a new declaration. If there is a previous 4272 // declaration of the same entity, the two will be linked via 4273 // PrevDecl. 4274 TagDecl *New; 4275 4276 if (Kind == TagDecl::TK_enum) { 4277 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4278 // enum X { A, B, C } D; D should chain to X. 4279 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4280 cast_or_null<EnumDecl>(PrevDecl)); 4281 // If this is an undefined enum, warn. 4282 if (TUK != TUK_Definition && !Invalid) { 4283 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4284 : diag::ext_forward_ref_enum; 4285 Diag(Loc, DK); 4286 } 4287 } else { 4288 // struct/union/class 4289 4290 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4291 // struct X { int A; } D; D should chain to X. 4292 if (getLangOptions().CPlusPlus) { 4293 // FIXME: Look for a way to use RecordDecl for simple structs. 4294 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4295 cast_or_null<CXXRecordDecl>(PrevDecl)); 4296 4297 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4298 StdBadAlloc = cast<CXXRecordDecl>(New); 4299 } else 4300 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4301 cast_or_null<RecordDecl>(PrevDecl)); 4302 } 4303 4304 if (Kind != TagDecl::TK_enum) { 4305 // Handle #pragma pack: if the #pragma pack stack has non-default 4306 // alignment, make up a packed attribute for this decl. These 4307 // attributes are checked when the ASTContext lays out the 4308 // structure. 4309 // 4310 // It is important for implementing the correct semantics that this 4311 // happen here (in act on tag decl). The #pragma pack stack is 4312 // maintained as a result of parser callbacks which can occur at 4313 // many points during the parsing of a struct declaration (because 4314 // the #pragma tokens are effectively skipped over during the 4315 // parsing of the struct). 4316 if (unsigned Alignment = getPragmaPackAlignment()) 4317 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4318 } 4319 4320 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4321 // C++ [dcl.typedef]p3: 4322 // [...] Similarly, in a given scope, a class or enumeration 4323 // shall not be declared with the same name as a typedef-name 4324 // that is declared in that scope and refers to a type other 4325 // than the class or enumeration itself. 4326 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4327 TypedefDecl *PrevTypedef = 0; 4328 if (Lookup.getKind() == LookupResult::Found) 4329 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4330 4331 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4332 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4333 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4334 Diag(Loc, diag::err_tag_definition_of_typedef) 4335 << Context.getTypeDeclType(New) 4336 << PrevTypedef->getUnderlyingType(); 4337 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4338 Invalid = true; 4339 } 4340 } 4341 4342 if (Invalid) 4343 New->setInvalidDecl(); 4344 4345 if (Attr) 4346 ProcessDeclAttributeList(S, New, Attr); 4347 4348 // If we're declaring or defining a tag in function prototype scope 4349 // in C, note that this type can only be used within the function. 4350 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4351 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4352 4353 // Set the lexical context. If the tag has a C++ scope specifier, the 4354 // lexical context will be different from the semantic context. 4355 New->setLexicalDeclContext(CurContext); 4356 4357 // Mark this as a friend decl if applicable. 4358 if (TUK == TUK_Friend) 4359 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4360 4361 // Set the access specifier. 4362 if (!Invalid && TUK != TUK_Friend) 4363 SetMemberAccessSpecifier(New, PrevDecl, AS); 4364 4365 if (TUK == TUK_Definition) 4366 New->startDefinition(); 4367 4368 // If this has an identifier, add it to the scope stack. 4369 if (TUK == TUK_Friend) { 4370 // We might be replacing an existing declaration in the lookup tables; 4371 // if so, borrow its access specifier. 4372 if (PrevDecl) 4373 New->setAccess(PrevDecl->getAccess()); 4374 4375 // Friend tag decls are visible in fairly strange ways. 4376 if (!CurContext->isDependentContext()) { 4377 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4378 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4379 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4380 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4381 } 4382 } else if (Name) { 4383 S = getNonFieldDeclScope(S); 4384 PushOnScopeChains(New, S); 4385 } else { 4386 CurContext->addDecl(New); 4387 } 4388 4389 // If this is the C FILE type, notify the AST context. 4390 if (IdentifierInfo *II = New->getIdentifier()) 4391 if (!New->isInvalidDecl() && 4392 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4393 II->isStr("FILE")) 4394 Context.setFILEDecl(New); 4395 4396 OwnedDecl = true; 4397 return DeclPtrTy::make(New); 4398} 4399 4400void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4401 AdjustDeclIfTemplate(TagD); 4402 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4403 4404 // Enter the tag context. 4405 PushDeclContext(S, Tag); 4406 4407 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4408 FieldCollector->StartClass(); 4409 4410 if (Record->getIdentifier()) { 4411 // C++ [class]p2: 4412 // [...] The class-name is also inserted into the scope of the 4413 // class itself; this is known as the injected-class-name. For 4414 // purposes of access checking, the injected-class-name is treated 4415 // as if it were a public member name. 4416 CXXRecordDecl *InjectedClassName 4417 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4418 CurContext, Record->getLocation(), 4419 Record->getIdentifier(), 4420 Record->getTagKeywordLoc(), 4421 Record); 4422 InjectedClassName->setImplicit(); 4423 InjectedClassName->setAccess(AS_public); 4424 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4425 InjectedClassName->setDescribedClassTemplate(Template); 4426 PushOnScopeChains(InjectedClassName, S); 4427 assert(InjectedClassName->isInjectedClassName() && 4428 "Broken injected-class-name"); 4429 } 4430 } 4431} 4432 4433void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4434 SourceLocation RBraceLoc) { 4435 AdjustDeclIfTemplate(TagD); 4436 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4437 Tag->setRBraceLoc(RBraceLoc); 4438 4439 if (isa<CXXRecordDecl>(Tag)) 4440 FieldCollector->FinishClass(); 4441 4442 // Exit this scope of this tag's definition. 4443 PopDeclContext(); 4444 4445 // Notify the consumer that we've defined a tag. 4446 Consumer.HandleTagDeclDefinition(Tag); 4447} 4448 4449// Note that FieldName may be null for anonymous bitfields. 4450bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4451 QualType FieldTy, const Expr *BitWidth, 4452 bool *ZeroWidth) { 4453 // Default to true; that shouldn't confuse checks for emptiness 4454 if (ZeroWidth) 4455 *ZeroWidth = true; 4456 4457 // C99 6.7.2.1p4 - verify the field type. 4458 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4459 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4460 // Handle incomplete types with specific error. 4461 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4462 return true; 4463 if (FieldName) 4464 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4465 << FieldName << FieldTy << BitWidth->getSourceRange(); 4466 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4467 << FieldTy << BitWidth->getSourceRange(); 4468 } 4469 4470 // If the bit-width is type- or value-dependent, don't try to check 4471 // it now. 4472 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4473 return false; 4474 4475 llvm::APSInt Value; 4476 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4477 return true; 4478 4479 if (Value != 0 && ZeroWidth) 4480 *ZeroWidth = false; 4481 4482 // Zero-width bitfield is ok for anonymous field. 4483 if (Value == 0 && FieldName) 4484 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4485 4486 if (Value.isSigned() && Value.isNegative()) { 4487 if (FieldName) 4488 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4489 << FieldName << Value.toString(10); 4490 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4491 << Value.toString(10); 4492 } 4493 4494 if (!FieldTy->isDependentType()) { 4495 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4496 if (Value.getZExtValue() > TypeSize) { 4497 if (FieldName) 4498 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4499 << FieldName << (unsigned)TypeSize; 4500 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4501 << (unsigned)TypeSize; 4502 } 4503 } 4504 4505 return false; 4506} 4507 4508/// ActOnField - Each field of a struct/union/class is passed into this in order 4509/// to create a FieldDecl object for it. 4510Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4511 SourceLocation DeclStart, 4512 Declarator &D, ExprTy *BitfieldWidth) { 4513 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4514 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4515 AS_public); 4516 return DeclPtrTy::make(Res); 4517} 4518 4519/// HandleField - Analyze a field of a C struct or a C++ data member. 4520/// 4521FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4522 SourceLocation DeclStart, 4523 Declarator &D, Expr *BitWidth, 4524 AccessSpecifier AS) { 4525 IdentifierInfo *II = D.getIdentifier(); 4526 SourceLocation Loc = DeclStart; 4527 if (II) Loc = D.getIdentifierLoc(); 4528 4529 DeclaratorInfo *DInfo = 0; 4530 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4531 if (getLangOptions().CPlusPlus) 4532 CheckExtraCXXDefaultArguments(D); 4533 4534 DiagnoseFunctionSpecifiers(D); 4535 4536 if (D.getDeclSpec().isThreadSpecified()) 4537 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4538 4539 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4540 4541 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4542 // Maybe we will complain about the shadowed template parameter. 4543 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4544 // Just pretend that we didn't see the previous declaration. 4545 PrevDecl = 0; 4546 } 4547 4548 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4549 PrevDecl = 0; 4550 4551 bool Mutable 4552 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4553 SourceLocation TSSL = D.getSourceRange().getBegin(); 4554 FieldDecl *NewFD 4555 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4556 AS, PrevDecl, &D); 4557 if (NewFD->isInvalidDecl() && PrevDecl) { 4558 // Don't introduce NewFD into scope; there's already something 4559 // with the same name in the same scope. 4560 } else if (II) { 4561 PushOnScopeChains(NewFD, S); 4562 } else 4563 Record->addDecl(NewFD); 4564 4565 return NewFD; 4566} 4567 4568/// \brief Build a new FieldDecl and check its well-formedness. 4569/// 4570/// This routine builds a new FieldDecl given the fields name, type, 4571/// record, etc. \p PrevDecl should refer to any previous declaration 4572/// with the same name and in the same scope as the field to be 4573/// created. 4574/// 4575/// \returns a new FieldDecl. 4576/// 4577/// \todo The Declarator argument is a hack. It will be removed once 4578FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4579 DeclaratorInfo *DInfo, 4580 RecordDecl *Record, SourceLocation Loc, 4581 bool Mutable, Expr *BitWidth, 4582 SourceLocation TSSL, 4583 AccessSpecifier AS, NamedDecl *PrevDecl, 4584 Declarator *D) { 4585 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4586 bool InvalidDecl = false; 4587 if (D) InvalidDecl = D->isInvalidType(); 4588 4589 // If we receive a broken type, recover by assuming 'int' and 4590 // marking this declaration as invalid. 4591 if (T.isNull()) { 4592 InvalidDecl = true; 4593 T = Context.IntTy; 4594 } 4595 4596 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4597 // than a variably modified type. 4598 if (T->isVariablyModifiedType()) { 4599 bool SizeIsNegative; 4600 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4601 SizeIsNegative); 4602 if (!FixedTy.isNull()) { 4603 Diag(Loc, diag::warn_illegal_constant_array_size); 4604 T = FixedTy; 4605 } else { 4606 if (SizeIsNegative) 4607 Diag(Loc, diag::err_typecheck_negative_array_size); 4608 else 4609 Diag(Loc, diag::err_typecheck_field_variable_size); 4610 InvalidDecl = true; 4611 } 4612 } 4613 4614 // Fields can not have abstract class types 4615 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4616 AbstractFieldType)) 4617 InvalidDecl = true; 4618 4619 bool ZeroWidth = false; 4620 // If this is declared as a bit-field, check the bit-field. 4621 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4622 InvalidDecl = true; 4623 DeleteExpr(BitWidth); 4624 BitWidth = 0; 4625 ZeroWidth = false; 4626 } 4627 4628 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4629 BitWidth, Mutable); 4630 if (InvalidDecl) 4631 NewFD->setInvalidDecl(); 4632 4633 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4634 Diag(Loc, diag::err_duplicate_member) << II; 4635 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4636 NewFD->setInvalidDecl(); 4637 } 4638 4639 if (getLangOptions().CPlusPlus) { 4640 QualType EltTy = Context.getBaseElementType(T); 4641 4642 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4643 4644 if (!T->isPODType()) 4645 CXXRecord->setPOD(false); 4646 if (!ZeroWidth) 4647 CXXRecord->setEmpty(false); 4648 4649 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4650 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4651 4652 if (!RDecl->hasTrivialConstructor()) 4653 CXXRecord->setHasTrivialConstructor(false); 4654 if (!RDecl->hasTrivialCopyConstructor()) 4655 CXXRecord->setHasTrivialCopyConstructor(false); 4656 if (!RDecl->hasTrivialCopyAssignment()) 4657 CXXRecord->setHasTrivialCopyAssignment(false); 4658 if (!RDecl->hasTrivialDestructor()) 4659 CXXRecord->setHasTrivialDestructor(false); 4660 4661 // C++ 9.5p1: An object of a class with a non-trivial 4662 // constructor, a non-trivial copy constructor, a non-trivial 4663 // destructor, or a non-trivial copy assignment operator 4664 // cannot be a member of a union, nor can an array of such 4665 // objects. 4666 // TODO: C++0x alters this restriction significantly. 4667 if (Record->isUnion()) { 4668 // We check for copy constructors before constructors 4669 // because otherwise we'll never get complaints about 4670 // copy constructors. 4671 4672 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4673 4674 CXXSpecialMember member; 4675 if (!RDecl->hasTrivialCopyConstructor()) 4676 member = CXXCopyConstructor; 4677 else if (!RDecl->hasTrivialConstructor()) 4678 member = CXXDefaultConstructor; 4679 else if (!RDecl->hasTrivialCopyAssignment()) 4680 member = CXXCopyAssignment; 4681 else if (!RDecl->hasTrivialDestructor()) 4682 member = CXXDestructor; 4683 else 4684 member = invalid; 4685 4686 if (member != invalid) { 4687 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4688 DiagnoseNontrivial(RT, member); 4689 NewFD->setInvalidDecl(); 4690 } 4691 } 4692 } 4693 } 4694 4695 // FIXME: We need to pass in the attributes given an AST 4696 // representation, not a parser representation. 4697 if (D) 4698 // FIXME: What to pass instead of TUScope? 4699 ProcessDeclAttributes(TUScope, NewFD, *D); 4700 4701 if (T.isObjCGCWeak()) 4702 Diag(Loc, diag::warn_attribute_weak_on_field); 4703 4704 NewFD->setAccess(AS); 4705 4706 // C++ [dcl.init.aggr]p1: 4707 // An aggregate is an array or a class (clause 9) with [...] no 4708 // private or protected non-static data members (clause 11). 4709 // A POD must be an aggregate. 4710 if (getLangOptions().CPlusPlus && 4711 (AS == AS_private || AS == AS_protected)) { 4712 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4713 CXXRecord->setAggregate(false); 4714 CXXRecord->setPOD(false); 4715 } 4716 4717 return NewFD; 4718} 4719 4720/// DiagnoseNontrivial - Given that a class has a non-trivial 4721/// special member, figure out why. 4722void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4723 QualType QT(T, 0U); 4724 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4725 4726 // Check whether the member was user-declared. 4727 switch (member) { 4728 case CXXDefaultConstructor: 4729 if (RD->hasUserDeclaredConstructor()) { 4730 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4731 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4732 if (!ci->isImplicitlyDefined(Context)) { 4733 SourceLocation CtorLoc = ci->getLocation(); 4734 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4735 return; 4736 } 4737 4738 assert(0 && "found no user-declared constructors"); 4739 return; 4740 } 4741 break; 4742 4743 case CXXCopyConstructor: 4744 if (RD->hasUserDeclaredCopyConstructor()) { 4745 SourceLocation CtorLoc = 4746 RD->getCopyConstructor(Context, 0)->getLocation(); 4747 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4748 return; 4749 } 4750 break; 4751 4752 case CXXCopyAssignment: 4753 if (RD->hasUserDeclaredCopyAssignment()) { 4754 // FIXME: this should use the location of the copy 4755 // assignment, not the type. 4756 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4757 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4758 return; 4759 } 4760 break; 4761 4762 case CXXDestructor: 4763 if (RD->hasUserDeclaredDestructor()) { 4764 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4765 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4766 return; 4767 } 4768 break; 4769 } 4770 4771 typedef CXXRecordDecl::base_class_iterator base_iter; 4772 4773 // Virtual bases and members inhibit trivial copying/construction, 4774 // but not trivial destruction. 4775 if (member != CXXDestructor) { 4776 // Check for virtual bases. vbases includes indirect virtual bases, 4777 // so we just iterate through the direct bases. 4778 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4779 if (bi->isVirtual()) { 4780 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4781 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4782 return; 4783 } 4784 4785 // Check for virtual methods. 4786 typedef CXXRecordDecl::method_iterator meth_iter; 4787 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4788 ++mi) { 4789 if (mi->isVirtual()) { 4790 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4791 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4792 return; 4793 } 4794 } 4795 } 4796 4797 bool (CXXRecordDecl::*hasTrivial)() const; 4798 switch (member) { 4799 case CXXDefaultConstructor: 4800 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4801 case CXXCopyConstructor: 4802 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4803 case CXXCopyAssignment: 4804 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4805 case CXXDestructor: 4806 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4807 default: 4808 assert(0 && "unexpected special member"); return; 4809 } 4810 4811 // Check for nontrivial bases (and recurse). 4812 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4813 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4814 assert(BaseRT); 4815 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4816 if (!(BaseRecTy->*hasTrivial)()) { 4817 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4818 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4819 DiagnoseNontrivial(BaseRT, member); 4820 return; 4821 } 4822 } 4823 4824 // Check for nontrivial members (and recurse). 4825 typedef RecordDecl::field_iterator field_iter; 4826 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4827 ++fi) { 4828 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4829 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4830 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4831 4832 if (!(EltRD->*hasTrivial)()) { 4833 SourceLocation FLoc = (*fi)->getLocation(); 4834 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4835 DiagnoseNontrivial(EltRT, member); 4836 return; 4837 } 4838 } 4839 } 4840 4841 assert(0 && "found no explanation for non-trivial member"); 4842} 4843 4844/// TranslateIvarVisibility - Translate visibility from a token ID to an 4845/// AST enum value. 4846static ObjCIvarDecl::AccessControl 4847TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4848 switch (ivarVisibility) { 4849 default: assert(0 && "Unknown visitibility kind"); 4850 case tok::objc_private: return ObjCIvarDecl::Private; 4851 case tok::objc_public: return ObjCIvarDecl::Public; 4852 case tok::objc_protected: return ObjCIvarDecl::Protected; 4853 case tok::objc_package: return ObjCIvarDecl::Package; 4854 } 4855} 4856 4857/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4858/// in order to create an IvarDecl object for it. 4859Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4860 SourceLocation DeclStart, 4861 DeclPtrTy IntfDecl, 4862 Declarator &D, ExprTy *BitfieldWidth, 4863 tok::ObjCKeywordKind Visibility) { 4864 4865 IdentifierInfo *II = D.getIdentifier(); 4866 Expr *BitWidth = (Expr*)BitfieldWidth; 4867 SourceLocation Loc = DeclStart; 4868 if (II) Loc = D.getIdentifierLoc(); 4869 4870 // FIXME: Unnamed fields can be handled in various different ways, for 4871 // example, unnamed unions inject all members into the struct namespace! 4872 4873 DeclaratorInfo *DInfo = 0; 4874 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4875 4876 if (BitWidth) { 4877 // 6.7.2.1p3, 6.7.2.1p4 4878 if (VerifyBitField(Loc, II, T, BitWidth)) { 4879 D.setInvalidType(); 4880 DeleteExpr(BitWidth); 4881 BitWidth = 0; 4882 } 4883 } else { 4884 // Not a bitfield. 4885 4886 // validate II. 4887 4888 } 4889 4890 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4891 // than a variably modified type. 4892 if (T->isVariablyModifiedType()) { 4893 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4894 D.setInvalidType(); 4895 } 4896 4897 // Get the visibility (access control) for this ivar. 4898 ObjCIvarDecl::AccessControl ac = 4899 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4900 : ObjCIvarDecl::None; 4901 // Must set ivar's DeclContext to its enclosing interface. 4902 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4903 DeclContext *EnclosingContext; 4904 if (ObjCImplementationDecl *IMPDecl = 4905 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4906 // Case of ivar declared in an implementation. Context is that of its class. 4907 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4908 assert(IDecl && "No class- ActOnIvar"); 4909 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4910 } else 4911 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4912 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4913 4914 // Construct the decl. 4915 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4916 EnclosingContext, Loc, II, T, 4917 DInfo, ac, (Expr *)BitfieldWidth); 4918 4919 if (II) { 4920 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4921 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4922 && !isa<TagDecl>(PrevDecl)) { 4923 Diag(Loc, diag::err_duplicate_member) << II; 4924 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4925 NewID->setInvalidDecl(); 4926 } 4927 } 4928 4929 // Process attributes attached to the ivar. 4930 ProcessDeclAttributes(S, NewID, D); 4931 4932 if (D.isInvalidType()) 4933 NewID->setInvalidDecl(); 4934 4935 if (II) { 4936 // FIXME: When interfaces are DeclContexts, we'll need to add 4937 // these to the interface. 4938 S->AddDecl(DeclPtrTy::make(NewID)); 4939 IdResolver.AddDecl(NewID); 4940 } 4941 4942 return DeclPtrTy::make(NewID); 4943} 4944 4945void Sema::ActOnFields(Scope* S, 4946 SourceLocation RecLoc, DeclPtrTy RecDecl, 4947 DeclPtrTy *Fields, unsigned NumFields, 4948 SourceLocation LBrac, SourceLocation RBrac, 4949 AttributeList *Attr) { 4950 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4951 assert(EnclosingDecl && "missing record or interface decl"); 4952 4953 // If the decl this is being inserted into is invalid, then it may be a 4954 // redeclaration or some other bogus case. Don't try to add fields to it. 4955 if (EnclosingDecl->isInvalidDecl()) { 4956 // FIXME: Deallocate fields? 4957 return; 4958 } 4959 4960 4961 // Verify that all the fields are okay. 4962 unsigned NumNamedMembers = 0; 4963 llvm::SmallVector<FieldDecl*, 32> RecFields; 4964 4965 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4966 for (unsigned i = 0; i != NumFields; ++i) { 4967 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4968 4969 // Get the type for the field. 4970 Type *FDTy = FD->getType().getTypePtr(); 4971 4972 if (!FD->isAnonymousStructOrUnion()) { 4973 // Remember all fields written by the user. 4974 RecFields.push_back(FD); 4975 } 4976 4977 // If the field is already invalid for some reason, don't emit more 4978 // diagnostics about it. 4979 if (FD->isInvalidDecl()) 4980 continue; 4981 4982 // C99 6.7.2.1p2: 4983 // A structure or union shall not contain a member with 4984 // incomplete or function type (hence, a structure shall not 4985 // contain an instance of itself, but may contain a pointer to 4986 // an instance of itself), except that the last member of a 4987 // structure with more than one named member may have incomplete 4988 // array type; such a structure (and any union containing, 4989 // possibly recursively, a member that is such a structure) 4990 // shall not be a member of a structure or an element of an 4991 // array. 4992 if (FDTy->isFunctionType()) { 4993 // Field declared as a function. 4994 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4995 << FD->getDeclName(); 4996 FD->setInvalidDecl(); 4997 EnclosingDecl->setInvalidDecl(); 4998 continue; 4999 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5000 Record && Record->isStruct()) { 5001 // Flexible array member. 5002 if (NumNamedMembers < 1) { 5003 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5004 << FD->getDeclName(); 5005 FD->setInvalidDecl(); 5006 EnclosingDecl->setInvalidDecl(); 5007 continue; 5008 } 5009 // Okay, we have a legal flexible array member at the end of the struct. 5010 if (Record) 5011 Record->setHasFlexibleArrayMember(true); 5012 } else if (!FDTy->isDependentType() && 5013 RequireCompleteType(FD->getLocation(), FD->getType(), 5014 diag::err_field_incomplete)) { 5015 // Incomplete type 5016 FD->setInvalidDecl(); 5017 EnclosingDecl->setInvalidDecl(); 5018 continue; 5019 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5020 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5021 // If this is a member of a union, then entire union becomes "flexible". 5022 if (Record && Record->isUnion()) { 5023 Record->setHasFlexibleArrayMember(true); 5024 } else { 5025 // If this is a struct/class and this is not the last element, reject 5026 // it. Note that GCC supports variable sized arrays in the middle of 5027 // structures. 5028 if (i != NumFields-1) 5029 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5030 << FD->getDeclName() << FD->getType(); 5031 else { 5032 // We support flexible arrays at the end of structs in 5033 // other structs as an extension. 5034 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5035 << FD->getDeclName(); 5036 if (Record) 5037 Record->setHasFlexibleArrayMember(true); 5038 } 5039 } 5040 } 5041 if (Record && FDTTy->getDecl()->hasObjectMember()) 5042 Record->setHasObjectMember(true); 5043 } else if (FDTy->isObjCInterfaceType()) { 5044 /// A field cannot be an Objective-c object 5045 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5046 FD->setInvalidDecl(); 5047 EnclosingDecl->setInvalidDecl(); 5048 continue; 5049 } else if (getLangOptions().ObjC1 && 5050 getLangOptions().getGCMode() != LangOptions::NonGC && 5051 Record && 5052 (FD->getType()->isObjCObjectPointerType() || 5053 FD->getType().isObjCGCStrong())) 5054 Record->setHasObjectMember(true); 5055 // Keep track of the number of named members. 5056 if (FD->getIdentifier()) 5057 ++NumNamedMembers; 5058 } 5059 5060 // Okay, we successfully defined 'Record'. 5061 if (Record) { 5062 Record->completeDefinition(Context); 5063 } else { 5064 ObjCIvarDecl **ClsFields = 5065 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5066 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5067 ID->setIVarList(ClsFields, RecFields.size(), Context); 5068 ID->setLocEnd(RBrac); 5069 // Add ivar's to class's DeclContext. 5070 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5071 ClsFields[i]->setLexicalDeclContext(ID); 5072 ID->addDecl(ClsFields[i]); 5073 } 5074 // Must enforce the rule that ivars in the base classes may not be 5075 // duplicates. 5076 if (ID->getSuperClass()) { 5077 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5078 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5079 ObjCIvarDecl* Ivar = (*IVI); 5080 5081 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5082 ObjCIvarDecl* prevIvar = 5083 ID->getSuperClass()->lookupInstanceVariable(II); 5084 if (prevIvar) { 5085 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5086 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5087 } 5088 } 5089 } 5090 } 5091 } else if (ObjCImplementationDecl *IMPDecl = 5092 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5093 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5094 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5095 // Ivar declared in @implementation never belongs to the implementation. 5096 // Only it is in implementation's lexical context. 5097 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5098 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5099 } 5100 } 5101 5102 if (Attr) 5103 ProcessDeclAttributeList(S, Record, Attr); 5104} 5105 5106EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5107 EnumConstantDecl *LastEnumConst, 5108 SourceLocation IdLoc, 5109 IdentifierInfo *Id, 5110 ExprArg val) { 5111 Expr *Val = (Expr *)val.get(); 5112 5113 llvm::APSInt EnumVal(32); 5114 QualType EltTy; 5115 if (Val && !Val->isTypeDependent()) { 5116 // Make sure to promote the operand type to int. 5117 UsualUnaryConversions(Val); 5118 if (Val != val.get()) { 5119 val.release(); 5120 val = Val; 5121 } 5122 5123 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5124 SourceLocation ExpLoc; 5125 if (!Val->isValueDependent() && 5126 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5127 Val = 0; 5128 } else { 5129 EltTy = Val->getType(); 5130 } 5131 } 5132 5133 if (!Val) { 5134 if (LastEnumConst) { 5135 // Assign the last value + 1. 5136 EnumVal = LastEnumConst->getInitVal(); 5137 ++EnumVal; 5138 5139 // Check for overflow on increment. 5140 if (EnumVal < LastEnumConst->getInitVal()) 5141 Diag(IdLoc, diag::warn_enum_value_overflow); 5142 5143 EltTy = LastEnumConst->getType(); 5144 } else { 5145 // First value, set to zero. 5146 EltTy = Context.IntTy; 5147 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5148 } 5149 } 5150 5151 val.release(); 5152 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5153 Val, EnumVal); 5154} 5155 5156 5157Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5158 DeclPtrTy lastEnumConst, 5159 SourceLocation IdLoc, 5160 IdentifierInfo *Id, 5161 SourceLocation EqualLoc, ExprTy *val) { 5162 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5163 EnumConstantDecl *LastEnumConst = 5164 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5165 Expr *Val = static_cast<Expr*>(val); 5166 5167 // The scope passed in may not be a decl scope. Zip up the scope tree until 5168 // we find one that is. 5169 S = getNonFieldDeclScope(S); 5170 5171 // Verify that there isn't already something declared with this name in this 5172 // scope. 5173 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5174 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5175 // Maybe we will complain about the shadowed template parameter. 5176 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5177 // Just pretend that we didn't see the previous declaration. 5178 PrevDecl = 0; 5179 } 5180 5181 if (PrevDecl) { 5182 // When in C++, we may get a TagDecl with the same name; in this case the 5183 // enum constant will 'hide' the tag. 5184 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5185 "Received TagDecl when not in C++!"); 5186 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5187 if (isa<EnumConstantDecl>(PrevDecl)) 5188 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5189 else 5190 Diag(IdLoc, diag::err_redefinition) << Id; 5191 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5192 if (Val) Val->Destroy(Context); 5193 return DeclPtrTy(); 5194 } 5195 } 5196 5197 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5198 IdLoc, Id, Owned(Val)); 5199 5200 // Register this decl in the current scope stack. 5201 if (New) 5202 PushOnScopeChains(New, S); 5203 5204 return DeclPtrTy::make(New); 5205} 5206 5207void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5208 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5209 DeclPtrTy *Elements, unsigned NumElements, 5210 Scope *S, AttributeList *Attr) { 5211 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5212 QualType EnumType = Context.getTypeDeclType(Enum); 5213 5214 if (Attr) 5215 ProcessDeclAttributeList(S, Enum, Attr); 5216 5217 // TODO: If the result value doesn't fit in an int, it must be a long or long 5218 // long value. ISO C does not support this, but GCC does as an extension, 5219 // emit a warning. 5220 unsigned IntWidth = Context.Target.getIntWidth(); 5221 unsigned CharWidth = Context.Target.getCharWidth(); 5222 unsigned ShortWidth = Context.Target.getShortWidth(); 5223 5224 // Verify that all the values are okay, compute the size of the values, and 5225 // reverse the list. 5226 unsigned NumNegativeBits = 0; 5227 unsigned NumPositiveBits = 0; 5228 5229 // Keep track of whether all elements have type int. 5230 bool AllElementsInt = true; 5231 5232 for (unsigned i = 0; i != NumElements; ++i) { 5233 EnumConstantDecl *ECD = 5234 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5235 if (!ECD) continue; // Already issued a diagnostic. 5236 5237 // If the enum value doesn't fit in an int, emit an extension warning. 5238 const llvm::APSInt &InitVal = ECD->getInitVal(); 5239 assert(InitVal.getBitWidth() >= IntWidth && 5240 "Should have promoted value to int"); 5241 if (InitVal.getBitWidth() > IntWidth) { 5242 llvm::APSInt V(InitVal); 5243 V.trunc(IntWidth); 5244 V.extend(InitVal.getBitWidth()); 5245 if (V != InitVal) 5246 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5247 << InitVal.toString(10); 5248 } 5249 5250 // Keep track of the size of positive and negative values. 5251 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5252 NumPositiveBits = std::max(NumPositiveBits, 5253 (unsigned)InitVal.getActiveBits()); 5254 else 5255 NumNegativeBits = std::max(NumNegativeBits, 5256 (unsigned)InitVal.getMinSignedBits()); 5257 5258 // Keep track of whether every enum element has type int (very commmon). 5259 if (AllElementsInt) 5260 AllElementsInt = ECD->getType() == Context.IntTy; 5261 } 5262 5263 // Figure out the type that should be used for this enum. 5264 // FIXME: Support -fshort-enums. 5265 QualType BestType; 5266 unsigned BestWidth; 5267 5268 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5269 5270 if (NumNegativeBits) { 5271 // If there is a negative value, figure out the smallest integer type (of 5272 // int/long/longlong) that fits. 5273 // If it's packed, check also if it fits a char or a short. 5274 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5275 BestType = Context.SignedCharTy; 5276 BestWidth = CharWidth; 5277 } else if (Packed && NumNegativeBits <= ShortWidth && 5278 NumPositiveBits < ShortWidth) { 5279 BestType = Context.ShortTy; 5280 BestWidth = ShortWidth; 5281 } 5282 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5283 BestType = Context.IntTy; 5284 BestWidth = IntWidth; 5285 } else { 5286 BestWidth = Context.Target.getLongWidth(); 5287 5288 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5289 BestType = Context.LongTy; 5290 else { 5291 BestWidth = Context.Target.getLongLongWidth(); 5292 5293 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5294 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5295 BestType = Context.LongLongTy; 5296 } 5297 } 5298 } else { 5299 // If there is no negative value, figure out which of uint, ulong, ulonglong 5300 // fits. 5301 // If it's packed, check also if it fits a char or a short. 5302 if (Packed && NumPositiveBits <= CharWidth) { 5303 BestType = Context.UnsignedCharTy; 5304 BestWidth = CharWidth; 5305 } else if (Packed && NumPositiveBits <= ShortWidth) { 5306 BestType = Context.UnsignedShortTy; 5307 BestWidth = ShortWidth; 5308 } 5309 else if (NumPositiveBits <= IntWidth) { 5310 BestType = Context.UnsignedIntTy; 5311 BestWidth = IntWidth; 5312 } else if (NumPositiveBits <= 5313 (BestWidth = Context.Target.getLongWidth())) { 5314 BestType = Context.UnsignedLongTy; 5315 } else { 5316 BestWidth = Context.Target.getLongLongWidth(); 5317 assert(NumPositiveBits <= BestWidth && 5318 "How could an initializer get larger than ULL?"); 5319 BestType = Context.UnsignedLongLongTy; 5320 } 5321 } 5322 5323 // Loop over all of the enumerator constants, changing their types to match 5324 // the type of the enum if needed. 5325 for (unsigned i = 0; i != NumElements; ++i) { 5326 EnumConstantDecl *ECD = 5327 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5328 if (!ECD) continue; // Already issued a diagnostic. 5329 5330 // Standard C says the enumerators have int type, but we allow, as an 5331 // extension, the enumerators to be larger than int size. If each 5332 // enumerator value fits in an int, type it as an int, otherwise type it the 5333 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5334 // that X has type 'int', not 'unsigned'. 5335 if (ECD->getType() == Context.IntTy) { 5336 // Make sure the init value is signed. 5337 llvm::APSInt IV = ECD->getInitVal(); 5338 IV.setIsSigned(true); 5339 ECD->setInitVal(IV); 5340 5341 if (getLangOptions().CPlusPlus) 5342 // C++ [dcl.enum]p4: Following the closing brace of an 5343 // enum-specifier, each enumerator has the type of its 5344 // enumeration. 5345 ECD->setType(EnumType); 5346 continue; // Already int type. 5347 } 5348 5349 // Determine whether the value fits into an int. 5350 llvm::APSInt InitVal = ECD->getInitVal(); 5351 bool FitsInInt; 5352 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5353 FitsInInt = InitVal.getActiveBits() < IntWidth; 5354 else 5355 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5356 5357 // If it fits into an integer type, force it. Otherwise force it to match 5358 // the enum decl type. 5359 QualType NewTy; 5360 unsigned NewWidth; 5361 bool NewSign; 5362 if (FitsInInt) { 5363 NewTy = Context.IntTy; 5364 NewWidth = IntWidth; 5365 NewSign = true; 5366 } else if (ECD->getType() == BestType) { 5367 // Already the right type! 5368 if (getLangOptions().CPlusPlus) 5369 // C++ [dcl.enum]p4: Following the closing brace of an 5370 // enum-specifier, each enumerator has the type of its 5371 // enumeration. 5372 ECD->setType(EnumType); 5373 continue; 5374 } else { 5375 NewTy = BestType; 5376 NewWidth = BestWidth; 5377 NewSign = BestType->isSignedIntegerType(); 5378 } 5379 5380 // Adjust the APSInt value. 5381 InitVal.extOrTrunc(NewWidth); 5382 InitVal.setIsSigned(NewSign); 5383 ECD->setInitVal(InitVal); 5384 5385 // Adjust the Expr initializer and type. 5386 if (ECD->getInitExpr()) 5387 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5388 CastExpr::CK_Unknown, 5389 ECD->getInitExpr(), 5390 /*isLvalue=*/false)); 5391 if (getLangOptions().CPlusPlus) 5392 // C++ [dcl.enum]p4: Following the closing brace of an 5393 // enum-specifier, each enumerator has the type of its 5394 // enumeration. 5395 ECD->setType(EnumType); 5396 else 5397 ECD->setType(NewTy); 5398 } 5399 5400 Enum->completeDefinition(Context, BestType); 5401} 5402 5403Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5404 ExprArg expr) { 5405 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5406 5407 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5408 Loc, AsmString); 5409 CurContext->addDecl(New); 5410 return DeclPtrTy::make(New); 5411} 5412 5413void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5414 SourceLocation PragmaLoc, 5415 SourceLocation NameLoc) { 5416 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5417 5418 if (PrevDecl) { 5419 PrevDecl->addAttr(::new (Context) WeakAttr()); 5420 } else { 5421 (void)WeakUndeclaredIdentifiers.insert( 5422 std::pair<IdentifierInfo*,WeakInfo> 5423 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5424 } 5425} 5426 5427void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5428 IdentifierInfo* AliasName, 5429 SourceLocation PragmaLoc, 5430 SourceLocation NameLoc, 5431 SourceLocation AliasNameLoc) { 5432 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5433 WeakInfo W = WeakInfo(Name, NameLoc); 5434 5435 if (PrevDecl) { 5436 if (!PrevDecl->hasAttr<AliasAttr>()) 5437 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5438 DeclApplyPragmaWeak(TUScope, ND, W); 5439 } else { 5440 (void)WeakUndeclaredIdentifiers.insert( 5441 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5442 } 5443} 5444