SemaDecl.cpp revision 7adb10fa317cd7eacb0959f775e77353d4f24ad1
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->getAsFunctionType(); 770 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 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()->getAsFunctionProtoType() && 820 Old->getNumParams() == New->getNumParams()) { 821 llvm::SmallVector<QualType, 16> ArgTypes; 822 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 823 const FunctionProtoType *OldProto 824 = Old->getType()->getAsFunctionProtoType(); 825 const FunctionProtoType *NewProto 826 = New->getType()->getAsFunctionProtoType(); 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()->getAsFunctionType()) { 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 1592 assert(false && "Unknown name kind"); 1593 return DeclarationName(); 1594} 1595 1596/// isNearlyMatchingFunction - Determine whether the C++ functions 1597/// Declaration and Definition are "nearly" matching. This heuristic 1598/// is used to improve diagnostics in the case where an out-of-line 1599/// function definition doesn't match any declaration within 1600/// the class or namespace. 1601static bool isNearlyMatchingFunction(ASTContext &Context, 1602 FunctionDecl *Declaration, 1603 FunctionDecl *Definition) { 1604 if (Declaration->param_size() != Definition->param_size()) 1605 return false; 1606 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1607 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1608 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1609 1610 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1611 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1612 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1613 return false; 1614 } 1615 1616 return true; 1617} 1618 1619Sema::DeclPtrTy 1620Sema::HandleDeclarator(Scope *S, Declarator &D, 1621 MultiTemplateParamsArg TemplateParamLists, 1622 bool IsFunctionDefinition) { 1623 DeclarationName Name = GetNameForDeclarator(D); 1624 1625 // All of these full declarators require an identifier. If it doesn't have 1626 // one, the ParsedFreeStandingDeclSpec action should be used. 1627 if (!Name) { 1628 if (!D.isInvalidType()) // Reject this if we think it is valid. 1629 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1630 diag::err_declarator_need_ident) 1631 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1632 return DeclPtrTy(); 1633 } 1634 1635 // The scope passed in may not be a decl scope. Zip up the scope tree until 1636 // we find one that is. 1637 while ((S->getFlags() & Scope::DeclScope) == 0 || 1638 (S->getFlags() & Scope::TemplateParamScope) != 0) 1639 S = S->getParent(); 1640 1641 // If this is an out-of-line definition of a member of a class template 1642 // or class template partial specialization, we may need to rebuild the 1643 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1644 // for more information. 1645 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1646 // handle expressions properly. 1647 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1648 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1649 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1650 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1651 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1652 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1653 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1654 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1655 // FIXME: Preserve type source info. 1656 QualType T = GetTypeFromParser(DS.getTypeRep()); 1657 EnterDeclaratorContext(S, DC); 1658 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1659 ExitDeclaratorContext(S); 1660 if (T.isNull()) 1661 return DeclPtrTy(); 1662 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1663 } 1664 } 1665 1666 DeclContext *DC; 1667 NamedDecl *PrevDecl; 1668 NamedDecl *New; 1669 1670 DeclaratorInfo *DInfo = 0; 1671 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1672 1673 // See if this is a redefinition of a variable in the same scope. 1674 if (D.getCXXScopeSpec().isInvalid()) { 1675 DC = CurContext; 1676 PrevDecl = 0; 1677 D.setInvalidType(); 1678 } else if (!D.getCXXScopeSpec().isSet()) { 1679 LookupNameKind NameKind = LookupOrdinaryName; 1680 1681 // If the declaration we're planning to build will be a function 1682 // or object with linkage, then look for another declaration with 1683 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1684 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1685 /* Do nothing*/; 1686 else if (R->isFunctionType()) { 1687 if (CurContext->isFunctionOrMethod() || 1688 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1689 NameKind = LookupRedeclarationWithLinkage; 1690 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1691 NameKind = LookupRedeclarationWithLinkage; 1692 else if (CurContext->getLookupContext()->isTranslationUnit() && 1693 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1694 NameKind = LookupRedeclarationWithLinkage; 1695 1696 DC = CurContext; 1697 PrevDecl = LookupName(S, Name, NameKind, true, 1698 NameKind == LookupRedeclarationWithLinkage, 1699 D.getIdentifierLoc()); 1700 } else { // Something like "int foo::x;" 1701 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1702 1703 if (!DC) { 1704 // If we could not compute the declaration context, it's because the 1705 // declaration context is dependent but does not refer to a class, 1706 // class template, or class template partial specialization. Complain 1707 // and return early, to avoid the coming semantic disaster. 1708 Diag(D.getIdentifierLoc(), 1709 diag::err_template_qualified_declarator_no_match) 1710 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1711 << D.getCXXScopeSpec().getRange(); 1712 return DeclPtrTy(); 1713 } 1714 1715 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1716 1717 // C++ 7.3.1.2p2: 1718 // Members (including explicit specializations of templates) of a named 1719 // namespace can also be defined outside that namespace by explicit 1720 // qualification of the name being defined, provided that the entity being 1721 // defined was already declared in the namespace and the definition appears 1722 // after the point of declaration in a namespace that encloses the 1723 // declarations namespace. 1724 // 1725 // Note that we only check the context at this point. We don't yet 1726 // have enough information to make sure that PrevDecl is actually 1727 // the declaration we want to match. For example, given: 1728 // 1729 // class X { 1730 // void f(); 1731 // void f(float); 1732 // }; 1733 // 1734 // void X::f(int) { } // ill-formed 1735 // 1736 // In this case, PrevDecl will point to the overload set 1737 // containing the two f's declared in X, but neither of them 1738 // matches. 1739 1740 // First check whether we named the global scope. 1741 if (isa<TranslationUnitDecl>(DC)) { 1742 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1743 << Name << D.getCXXScopeSpec().getRange(); 1744 } else if (!CurContext->Encloses(DC)) { 1745 // The qualifying scope doesn't enclose the original declaration. 1746 // Emit diagnostic based on current scope. 1747 SourceLocation L = D.getIdentifierLoc(); 1748 SourceRange R = D.getCXXScopeSpec().getRange(); 1749 if (isa<FunctionDecl>(CurContext)) 1750 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1751 else 1752 Diag(L, diag::err_invalid_declarator_scope) 1753 << Name << cast<NamedDecl>(DC) << R; 1754 D.setInvalidType(); 1755 } 1756 } 1757 1758 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1759 // Maybe we will complain about the shadowed template parameter. 1760 if (!D.isInvalidType()) 1761 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1762 D.setInvalidType(); 1763 1764 // Just pretend that we didn't see the previous declaration. 1765 PrevDecl = 0; 1766 } 1767 1768 // In C++, the previous declaration we find might be a tag type 1769 // (class or enum). In this case, the new declaration will hide the 1770 // tag type. Note that this does does not apply if we're declaring a 1771 // typedef (C++ [dcl.typedef]p4). 1772 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1773 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1774 PrevDecl = 0; 1775 1776 bool Redeclaration = false; 1777 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1778 if (TemplateParamLists.size()) { 1779 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1780 return DeclPtrTy(); 1781 } 1782 1783 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1784 } else if (R->isFunctionType()) { 1785 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1786 move(TemplateParamLists), 1787 IsFunctionDefinition, Redeclaration); 1788 } else { 1789 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1790 move(TemplateParamLists), 1791 Redeclaration); 1792 } 1793 1794 if (New == 0) 1795 return DeclPtrTy(); 1796 1797 // If this has an identifier and is not an invalid redeclaration, 1798 // add it to the scope stack. 1799 if (Name && !(Redeclaration && New->isInvalidDecl())) 1800 PushOnScopeChains(New, S); 1801 1802 return DeclPtrTy::make(New); 1803} 1804 1805/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1806/// types into constant array types in certain situations which would otherwise 1807/// be errors (for GCC compatibility). 1808static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1809 ASTContext &Context, 1810 bool &SizeIsNegative) { 1811 // This method tries to turn a variable array into a constant 1812 // array even when the size isn't an ICE. This is necessary 1813 // for compatibility with code that depends on gcc's buggy 1814 // constant expression folding, like struct {char x[(int)(char*)2];} 1815 SizeIsNegative = false; 1816 1817 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1818 QualType Pointee = PTy->getPointeeType(); 1819 QualType FixedType = 1820 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1821 if (FixedType.isNull()) return FixedType; 1822 FixedType = Context.getPointerType(FixedType); 1823 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1824 return FixedType; 1825 } 1826 1827 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1828 if (!VLATy) 1829 return QualType(); 1830 // FIXME: We should probably handle this case 1831 if (VLATy->getElementType()->isVariablyModifiedType()) 1832 return QualType(); 1833 1834 Expr::EvalResult EvalResult; 1835 if (!VLATy->getSizeExpr() || 1836 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1837 !EvalResult.Val.isInt()) 1838 return QualType(); 1839 1840 llvm::APSInt &Res = EvalResult.Val.getInt(); 1841 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1842 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1843 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1844 // so as to transfer ownership to the ConstantArrayWithExpr. 1845 // Alternatively, we could "clone" it (how?). 1846 // Since we don't know how to do things above, we just use the 1847 // very same Expr*. 1848 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1849 Res, ArySizeExpr, 1850 ArrayType::Normal, 0, 1851 VLATy->getBracketsRange()); 1852 } 1853 1854 SizeIsNegative = true; 1855 return QualType(); 1856} 1857 1858/// \brief Register the given locally-scoped external C declaration so 1859/// that it can be found later for redeclarations 1860void 1861Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1862 Scope *S) { 1863 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1864 "Decl is not a locally-scoped decl!"); 1865 // Note that we have a locally-scoped external with this name. 1866 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1867 1868 if (!PrevDecl) 1869 return; 1870 1871 // If there was a previous declaration of this variable, it may be 1872 // in our identifier chain. Update the identifier chain with the new 1873 // declaration. 1874 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1875 // The previous declaration was found on the identifer resolver 1876 // chain, so remove it from its scope. 1877 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1878 S = S->getParent(); 1879 1880 if (S) 1881 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1882 } 1883} 1884 1885/// \brief Diagnose function specifiers on a declaration of an identifier that 1886/// does not identify a function. 1887void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1888 // FIXME: We should probably indicate the identifier in question to avoid 1889 // confusion for constructs like "inline int a(), b;" 1890 if (D.getDeclSpec().isInlineSpecified()) 1891 Diag(D.getDeclSpec().getInlineSpecLoc(), 1892 diag::err_inline_non_function); 1893 1894 if (D.getDeclSpec().isVirtualSpecified()) 1895 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1896 diag::err_virtual_non_function); 1897 1898 if (D.getDeclSpec().isExplicitSpecified()) 1899 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1900 diag::err_explicit_non_function); 1901} 1902 1903NamedDecl* 1904Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1905 QualType R, DeclaratorInfo *DInfo, 1906 Decl* PrevDecl, bool &Redeclaration) { 1907 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1908 if (D.getCXXScopeSpec().isSet()) { 1909 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1910 << D.getCXXScopeSpec().getRange(); 1911 D.setInvalidType(); 1912 // Pretend we didn't see the scope specifier. 1913 DC = 0; 1914 } 1915 1916 if (getLangOptions().CPlusPlus) { 1917 // Check that there are no default arguments (C++ only). 1918 CheckExtraCXXDefaultArguments(D); 1919 } 1920 1921 DiagnoseFunctionSpecifiers(D); 1922 1923 if (D.getDeclSpec().isThreadSpecified()) 1924 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1925 1926 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1927 if (!NewTD) return 0; 1928 1929 if (D.isInvalidType()) 1930 NewTD->setInvalidDecl(); 1931 1932 // Handle attributes prior to checking for duplicates in MergeVarDecl 1933 ProcessDeclAttributes(S, NewTD, D); 1934 // Merge the decl with the existing one if appropriate. If the decl is 1935 // in an outer scope, it isn't the same thing. 1936 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1937 Redeclaration = true; 1938 MergeTypeDefDecl(NewTD, PrevDecl); 1939 } 1940 1941 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1942 // then it shall have block scope. 1943 QualType T = NewTD->getUnderlyingType(); 1944 if (T->isVariablyModifiedType()) { 1945 CurFunctionNeedsScopeChecking = true; 1946 1947 if (S->getFnParent() == 0) { 1948 bool SizeIsNegative; 1949 QualType FixedTy = 1950 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1951 if (!FixedTy.isNull()) { 1952 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1953 NewTD->setUnderlyingType(FixedTy); 1954 } else { 1955 if (SizeIsNegative) 1956 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1957 else if (T->isVariableArrayType()) 1958 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1959 else 1960 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1961 NewTD->setInvalidDecl(); 1962 } 1963 } 1964 } 1965 1966 // If this is the C FILE type, notify the AST context. 1967 if (IdentifierInfo *II = NewTD->getIdentifier()) 1968 if (!NewTD->isInvalidDecl() && 1969 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1970 if (II->isStr("FILE")) 1971 Context.setFILEDecl(NewTD); 1972 else if (II->isStr("jmp_buf")) 1973 Context.setjmp_bufDecl(NewTD); 1974 else if (II->isStr("sigjmp_buf")) 1975 Context.setsigjmp_bufDecl(NewTD); 1976 } 1977 1978 return NewTD; 1979} 1980 1981/// \brief Determines whether the given declaration is an out-of-scope 1982/// previous declaration. 1983/// 1984/// This routine should be invoked when name lookup has found a 1985/// previous declaration (PrevDecl) that is not in the scope where a 1986/// new declaration by the same name is being introduced. If the new 1987/// declaration occurs in a local scope, previous declarations with 1988/// linkage may still be considered previous declarations (C99 1989/// 6.2.2p4-5, C++ [basic.link]p6). 1990/// 1991/// \param PrevDecl the previous declaration found by name 1992/// lookup 1993/// 1994/// \param DC the context in which the new declaration is being 1995/// declared. 1996/// 1997/// \returns true if PrevDecl is an out-of-scope previous declaration 1998/// for a new delcaration with the same name. 1999static bool 2000isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2001 ASTContext &Context) { 2002 if (!PrevDecl) 2003 return 0; 2004 2005 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2006 // case we need to check each of the overloaded functions. 2007 if (!PrevDecl->hasLinkage()) 2008 return false; 2009 2010 if (Context.getLangOptions().CPlusPlus) { 2011 // C++ [basic.link]p6: 2012 // If there is a visible declaration of an entity with linkage 2013 // having the same name and type, ignoring entities declared 2014 // outside the innermost enclosing namespace scope, the block 2015 // scope declaration declares that same entity and receives the 2016 // linkage of the previous declaration. 2017 DeclContext *OuterContext = DC->getLookupContext(); 2018 if (!OuterContext->isFunctionOrMethod()) 2019 // This rule only applies to block-scope declarations. 2020 return false; 2021 else { 2022 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2023 if (PrevOuterContext->isRecord()) 2024 // We found a member function: ignore it. 2025 return false; 2026 else { 2027 // Find the innermost enclosing namespace for the new and 2028 // previous declarations. 2029 while (!OuterContext->isFileContext()) 2030 OuterContext = OuterContext->getParent(); 2031 while (!PrevOuterContext->isFileContext()) 2032 PrevOuterContext = PrevOuterContext->getParent(); 2033 2034 // The previous declaration is in a different namespace, so it 2035 // isn't the same function. 2036 if (OuterContext->getPrimaryContext() != 2037 PrevOuterContext->getPrimaryContext()) 2038 return false; 2039 } 2040 } 2041 } 2042 2043 return true; 2044} 2045 2046NamedDecl* 2047Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2048 QualType R, DeclaratorInfo *DInfo, 2049 NamedDecl* PrevDecl, 2050 MultiTemplateParamsArg TemplateParamLists, 2051 bool &Redeclaration) { 2052 DeclarationName Name = GetNameForDeclarator(D); 2053 2054 // Check that there are no default arguments (C++ only). 2055 if (getLangOptions().CPlusPlus) 2056 CheckExtraCXXDefaultArguments(D); 2057 2058 VarDecl *NewVD; 2059 VarDecl::StorageClass SC; 2060 switch (D.getDeclSpec().getStorageClassSpec()) { 2061 default: assert(0 && "Unknown storage class!"); 2062 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2063 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2064 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2065 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2066 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2067 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2068 case DeclSpec::SCS_mutable: 2069 // mutable can only appear on non-static class members, so it's always 2070 // an error here 2071 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2072 D.setInvalidType(); 2073 SC = VarDecl::None; 2074 break; 2075 } 2076 2077 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2078 if (!II) { 2079 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2080 << Name.getAsString(); 2081 return 0; 2082 } 2083 2084 DiagnoseFunctionSpecifiers(D); 2085 2086 if (!DC->isRecord() && S->getFnParent() == 0) { 2087 // C99 6.9p2: The storage-class specifiers auto and register shall not 2088 // appear in the declaration specifiers in an external declaration. 2089 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2090 2091 // If this is a register variable with an asm label specified, then this 2092 // is a GNU extension. 2093 if (SC == VarDecl::Register && D.getAsmLabel()) 2094 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2095 else 2096 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2097 D.setInvalidType(); 2098 } 2099 } 2100 if (DC->isRecord() && !CurContext->isRecord()) { 2101 // This is an out-of-line definition of a static data member. 2102 if (SC == VarDecl::Static) { 2103 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2104 diag::err_static_out_of_line) 2105 << CodeModificationHint::CreateRemoval( 2106 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2107 } else if (SC == VarDecl::None) 2108 SC = VarDecl::Static; 2109 } 2110 if (SC == VarDecl::Static) { 2111 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2112 if (RD->isLocalClass()) 2113 Diag(D.getIdentifierLoc(), 2114 diag::err_static_data_member_not_allowed_in_local_class) 2115 << Name << RD->getDeclName(); 2116 } 2117 } 2118 2119 // Match up the template parameter lists with the scope specifier, then 2120 // determine whether we have a template or a template specialization. 2121 if (TemplateParameterList *TemplateParams 2122 = MatchTemplateParametersToScopeSpecifier( 2123 D.getDeclSpec().getSourceRange().getBegin(), 2124 D.getCXXScopeSpec(), 2125 (TemplateParameterList**)TemplateParamLists.get(), 2126 TemplateParamLists.size())) { 2127 if (TemplateParams->size() > 0) { 2128 // There is no such thing as a variable template. 2129 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2130 << II 2131 << SourceRange(TemplateParams->getTemplateLoc(), 2132 TemplateParams->getRAngleLoc()); 2133 return 0; 2134 } else { 2135 // There is an extraneous 'template<>' for this variable. Complain 2136 // about it, but allow the declaration of the variable. 2137 Diag(TemplateParams->getTemplateLoc(), 2138 diag::err_template_variable_noparams) 2139 << II 2140 << SourceRange(TemplateParams->getTemplateLoc(), 2141 TemplateParams->getRAngleLoc()); 2142 } 2143 } 2144 2145 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2146 II, R, DInfo, SC); 2147 2148 if (D.isInvalidType()) 2149 NewVD->setInvalidDecl(); 2150 2151 if (D.getDeclSpec().isThreadSpecified()) { 2152 if (NewVD->hasLocalStorage()) 2153 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2154 else if (!Context.Target.isTLSSupported()) 2155 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2156 else 2157 NewVD->setThreadSpecified(true); 2158 } 2159 2160 // Set the lexical context. If the declarator has a C++ scope specifier, the 2161 // lexical context will be different from the semantic context. 2162 NewVD->setLexicalDeclContext(CurContext); 2163 2164 // Handle attributes prior to checking for duplicates in MergeVarDecl 2165 ProcessDeclAttributes(S, NewVD, D); 2166 2167 // Handle GNU asm-label extension (encoded as an attribute). 2168 if (Expr *E = (Expr*) D.getAsmLabel()) { 2169 // The parser guarantees this is a string. 2170 StringLiteral *SE = cast<StringLiteral>(E); 2171 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2172 SE->getByteLength()))); 2173 } 2174 2175 // If name lookup finds a previous declaration that is not in the 2176 // same scope as the new declaration, this may still be an 2177 // acceptable redeclaration. 2178 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2179 !(NewVD->hasLinkage() && 2180 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2181 PrevDecl = 0; 2182 2183 // Merge the decl with the existing one if appropriate. 2184 if (PrevDecl) { 2185 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2186 // The user tried to define a non-static data member 2187 // out-of-line (C++ [dcl.meaning]p1). 2188 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2189 << D.getCXXScopeSpec().getRange(); 2190 PrevDecl = 0; 2191 NewVD->setInvalidDecl(); 2192 } 2193 } else if (D.getCXXScopeSpec().isSet()) { 2194 // No previous declaration in the qualifying scope. 2195 NestedNameSpecifier *NNS = 2196 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2197 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2198 D.getCXXScopeSpec().getRange()); 2199 NewVD->setInvalidDecl(); 2200 } 2201 2202 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2203 2204 // attributes declared post-definition are currently ignored 2205 if (PrevDecl) { 2206 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2207 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2208 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2209 Diag(Def->getLocation(), diag::note_previous_definition); 2210 } 2211 } 2212 2213 // If this is a locally-scoped extern C variable, update the map of 2214 // such variables. 2215 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2216 !NewVD->isInvalidDecl()) 2217 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2218 2219 return NewVD; 2220} 2221 2222/// \brief Perform semantic checking on a newly-created variable 2223/// declaration. 2224/// 2225/// This routine performs all of the type-checking required for a 2226/// variable declaration once it has been built. It is used both to 2227/// check variables after they have been parsed and their declarators 2228/// have been translated into a declaration, and to check variables 2229/// that have been instantiated from a template. 2230/// 2231/// Sets NewVD->isInvalidDecl() if an error was encountered. 2232void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2233 bool &Redeclaration) { 2234 // If the decl is already known invalid, don't check it. 2235 if (NewVD->isInvalidDecl()) 2236 return; 2237 2238 QualType T = NewVD->getType(); 2239 2240 if (T->isObjCInterfaceType()) { 2241 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2242 return NewVD->setInvalidDecl(); 2243 } 2244 2245 // The variable can not have an abstract class type. 2246 if (RequireNonAbstractType(NewVD->getLocation(), T, 2247 diag::err_abstract_type_in_decl, 2248 AbstractVariableType)) 2249 return NewVD->setInvalidDecl(); 2250 2251 // Emit an error if an address space was applied to decl with local storage. 2252 // This includes arrays of objects with address space qualifiers, but not 2253 // automatic variables that point to other address spaces. 2254 // ISO/IEC TR 18037 S5.1.2 2255 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2256 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2257 return NewVD->setInvalidDecl(); 2258 } 2259 2260 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2261 && !NewVD->hasAttr<BlocksAttr>()) 2262 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2263 2264 bool isVM = T->isVariablyModifiedType(); 2265 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2266 NewVD->hasAttr<BlocksAttr>()) 2267 CurFunctionNeedsScopeChecking = true; 2268 2269 if ((isVM && NewVD->hasLinkage()) || 2270 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2271 bool SizeIsNegative; 2272 QualType FixedTy = 2273 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2274 2275 if (FixedTy.isNull() && T->isVariableArrayType()) { 2276 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2277 // FIXME: This won't give the correct result for 2278 // int a[10][n]; 2279 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2280 2281 if (NewVD->isFileVarDecl()) 2282 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2283 << SizeRange; 2284 else if (NewVD->getStorageClass() == VarDecl::Static) 2285 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2286 << SizeRange; 2287 else 2288 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2289 << SizeRange; 2290 return NewVD->setInvalidDecl(); 2291 } 2292 2293 if (FixedTy.isNull()) { 2294 if (NewVD->isFileVarDecl()) 2295 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2296 else 2297 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2298 return NewVD->setInvalidDecl(); 2299 } 2300 2301 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2302 NewVD->setType(FixedTy); 2303 } 2304 2305 if (!PrevDecl && NewVD->isExternC()) { 2306 // Since we did not find anything by this name and we're declaring 2307 // an extern "C" variable, look for a non-visible extern "C" 2308 // declaration with the same name. 2309 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2310 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2311 if (Pos != LocallyScopedExternalDecls.end()) 2312 PrevDecl = Pos->second; 2313 } 2314 2315 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2316 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2317 << T; 2318 return NewVD->setInvalidDecl(); 2319 } 2320 2321 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2322 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2323 return NewVD->setInvalidDecl(); 2324 } 2325 2326 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2327 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2328 return NewVD->setInvalidDecl(); 2329 } 2330 2331 if (PrevDecl) { 2332 Redeclaration = true; 2333 MergeVarDecl(NewVD, PrevDecl); 2334 } 2335} 2336 2337static bool isUsingDecl(Decl *D) { 2338 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2339} 2340 2341NamedDecl* 2342Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2343 QualType R, DeclaratorInfo *DInfo, 2344 NamedDecl* PrevDecl, 2345 MultiTemplateParamsArg TemplateParamLists, 2346 bool IsFunctionDefinition, bool &Redeclaration) { 2347 assert(R.getTypePtr()->isFunctionType()); 2348 2349 DeclarationName Name = GetNameForDeclarator(D); 2350 FunctionDecl::StorageClass SC = FunctionDecl::None; 2351 switch (D.getDeclSpec().getStorageClassSpec()) { 2352 default: assert(0 && "Unknown storage class!"); 2353 case DeclSpec::SCS_auto: 2354 case DeclSpec::SCS_register: 2355 case DeclSpec::SCS_mutable: 2356 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2357 diag::err_typecheck_sclass_func); 2358 D.setInvalidType(); 2359 break; 2360 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2361 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2362 case DeclSpec::SCS_static: { 2363 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2364 // C99 6.7.1p5: 2365 // The declaration of an identifier for a function that has 2366 // block scope shall have no explicit storage-class specifier 2367 // other than extern 2368 // See also (C++ [dcl.stc]p4). 2369 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2370 diag::err_static_block_func); 2371 SC = FunctionDecl::None; 2372 } else 2373 SC = FunctionDecl::Static; 2374 break; 2375 } 2376 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2377 } 2378 2379 if (D.getDeclSpec().isThreadSpecified()) 2380 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2381 2382 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2383 bool isInline = D.getDeclSpec().isInlineSpecified(); 2384 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2385 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2386 2387 // Check that the return type is not an abstract class type. 2388 // For record types, this is done by the AbstractClassUsageDiagnoser once 2389 // the class has been completely parsed. 2390 if (!DC->isRecord() && 2391 RequireNonAbstractType(D.getIdentifierLoc(), 2392 R->getAsFunctionType()->getResultType(), 2393 diag::err_abstract_type_in_decl, 2394 AbstractReturnType)) 2395 D.setInvalidType(); 2396 2397 // Do not allow returning a objc interface by-value. 2398 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2399 Diag(D.getIdentifierLoc(), 2400 diag::err_object_cannot_be_passed_returned_by_value) << 0 2401 << R->getAsFunctionType()->getResultType(); 2402 D.setInvalidType(); 2403 } 2404 2405 bool isVirtualOkay = false; 2406 FunctionDecl *NewFD; 2407 2408 if (isFriend) { 2409 // DC is the namespace in which the function is being declared. 2410 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2411 "friend function being created in a non-namespace context"); 2412 2413 // C++ [class.friend]p5 2414 // A function can be defined in a friend declaration of a 2415 // class . . . . Such a function is implicitly inline. 2416 isInline |= IsFunctionDefinition; 2417 } 2418 2419 if (D.getKind() == Declarator::DK_Constructor) { 2420 // This is a C++ constructor declaration. 2421 assert(DC->isRecord() && 2422 "Constructors can only be declared in a member context"); 2423 2424 R = CheckConstructorDeclarator(D, R, SC); 2425 2426 // Create the new declaration 2427 NewFD = CXXConstructorDecl::Create(Context, 2428 cast<CXXRecordDecl>(DC), 2429 D.getIdentifierLoc(), Name, R, DInfo, 2430 isExplicit, isInline, 2431 /*isImplicitlyDeclared=*/false); 2432 } else if (D.getKind() == Declarator::DK_Destructor) { 2433 // This is a C++ destructor declaration. 2434 if (DC->isRecord()) { 2435 R = CheckDestructorDeclarator(D, SC); 2436 2437 NewFD = CXXDestructorDecl::Create(Context, 2438 cast<CXXRecordDecl>(DC), 2439 D.getIdentifierLoc(), Name, R, 2440 isInline, 2441 /*isImplicitlyDeclared=*/false); 2442 2443 isVirtualOkay = true; 2444 } else { 2445 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2446 2447 // Create a FunctionDecl to satisfy the function definition parsing 2448 // code path. 2449 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2450 Name, R, DInfo, SC, isInline, 2451 /*hasPrototype=*/true); 2452 D.setInvalidType(); 2453 } 2454 } else if (D.getKind() == Declarator::DK_Conversion) { 2455 if (!DC->isRecord()) { 2456 Diag(D.getIdentifierLoc(), 2457 diag::err_conv_function_not_member); 2458 return 0; 2459 } 2460 2461 CheckConversionDeclarator(D, R, SC); 2462 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2463 D.getIdentifierLoc(), Name, R, DInfo, 2464 isInline, isExplicit); 2465 2466 isVirtualOkay = true; 2467 } else if (DC->isRecord()) { 2468 // If the of the function is the same as the name of the record, then this 2469 // must be an invalid constructor that has a return type. 2470 // (The parser checks for a return type and makes the declarator a 2471 // constructor if it has no return type). 2472 // must have an invalid constructor that has a return type 2473 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2474 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2475 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2476 << SourceRange(D.getIdentifierLoc()); 2477 return 0; 2478 } 2479 2480 // This is a C++ method declaration. 2481 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2482 D.getIdentifierLoc(), Name, R, DInfo, 2483 (SC == FunctionDecl::Static), isInline); 2484 2485 isVirtualOkay = (SC != FunctionDecl::Static); 2486 } else { 2487 // Determine whether the function was written with a 2488 // prototype. This true when: 2489 // - we're in C++ (where every function has a prototype), 2490 // - there is a prototype in the declarator, or 2491 // - the type R of the function is some kind of typedef or other reference 2492 // to a type name (which eventually refers to a function type). 2493 bool HasPrototype = 2494 getLangOptions().CPlusPlus || 2495 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2496 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2497 2498 NewFD = FunctionDecl::Create(Context, DC, 2499 D.getIdentifierLoc(), 2500 Name, R, DInfo, SC, isInline, HasPrototype); 2501 } 2502 2503 if (D.isInvalidType()) 2504 NewFD->setInvalidDecl(); 2505 2506 // Set the lexical context. If the declarator has a C++ 2507 // scope specifier, or is the object of a friend declaration, the 2508 // lexical context will be different from the semantic context. 2509 NewFD->setLexicalDeclContext(CurContext); 2510 2511 if (isFriend) 2512 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2513 2514 // Match up the template parameter lists with the scope specifier, then 2515 // determine whether we have a template or a template specialization. 2516 FunctionTemplateDecl *FunctionTemplate = 0; 2517 if (TemplateParameterList *TemplateParams 2518 = MatchTemplateParametersToScopeSpecifier( 2519 D.getDeclSpec().getSourceRange().getBegin(), 2520 D.getCXXScopeSpec(), 2521 (TemplateParameterList**)TemplateParamLists.get(), 2522 TemplateParamLists.size())) { 2523 if (TemplateParams->size() > 0) { 2524 // This is a function template 2525 2526 // Check that we can declare a template here. 2527 if (CheckTemplateDeclScope(S, TemplateParams)) 2528 return 0; 2529 2530 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2531 NewFD->getLocation(), 2532 Name, TemplateParams, 2533 NewFD); 2534 FunctionTemplate->setLexicalDeclContext(CurContext); 2535 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2536 } else { 2537 // FIXME: Handle function template specializations 2538 } 2539 2540 // FIXME: Free this memory properly. 2541 TemplateParamLists.release(); 2542 } 2543 2544 // C++ [dcl.fct.spec]p5: 2545 // The virtual specifier shall only be used in declarations of 2546 // nonstatic class member functions that appear within a 2547 // member-specification of a class declaration; see 10.3. 2548 // 2549 if (isVirtual && !NewFD->isInvalidDecl()) { 2550 if (!isVirtualOkay) { 2551 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2552 diag::err_virtual_non_function); 2553 } else if (!CurContext->isRecord()) { 2554 // 'virtual' was specified outside of the class. 2555 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2556 << CodeModificationHint::CreateRemoval( 2557 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2558 } else { 2559 // Okay: Add virtual to the method. 2560 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2561 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2562 CurClass->setAggregate(false); 2563 CurClass->setPOD(false); 2564 CurClass->setEmpty(false); 2565 CurClass->setPolymorphic(true); 2566 CurClass->setHasTrivialConstructor(false); 2567 CurClass->setHasTrivialCopyConstructor(false); 2568 CurClass->setHasTrivialCopyAssignment(false); 2569 } 2570 } 2571 2572 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2573 // Look for virtual methods in base classes that this method might override. 2574 2575 BasePaths Paths; 2576 if (LookupInBases(cast<CXXRecordDecl>(DC), 2577 MemberLookupCriteria(NewMD), Paths)) { 2578 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2579 E = Paths.found_decls_end(); I != E; ++I) { 2580 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2581 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2582 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2583 NewMD->addOverriddenMethod(OldMD); 2584 } 2585 } 2586 } 2587 } 2588 2589 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2590 !CurContext->isRecord()) { 2591 // C++ [class.static]p1: 2592 // A data or function member of a class may be declared static 2593 // in a class definition, in which case it is a static member of 2594 // the class. 2595 2596 // Complain about the 'static' specifier if it's on an out-of-line 2597 // member function definition. 2598 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2599 diag::err_static_out_of_line) 2600 << CodeModificationHint::CreateRemoval( 2601 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2602 } 2603 2604 // Handle GNU asm-label extension (encoded as an attribute). 2605 if (Expr *E = (Expr*) D.getAsmLabel()) { 2606 // The parser guarantees this is a string. 2607 StringLiteral *SE = cast<StringLiteral>(E); 2608 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2609 SE->getByteLength()))); 2610 } 2611 2612 // Copy the parameter declarations from the declarator D to the function 2613 // declaration NewFD, if they are available. First scavenge them into Params. 2614 llvm::SmallVector<ParmVarDecl*, 16> Params; 2615 if (D.getNumTypeObjects() > 0) { 2616 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2617 2618 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2619 // function that takes no arguments, not a function that takes a 2620 // single void argument. 2621 // We let through "const void" here because Sema::GetTypeForDeclarator 2622 // already checks for that case. 2623 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2624 FTI.ArgInfo[0].Param && 2625 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2626 // Empty arg list, don't push any params. 2627 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2628 2629 // In C++, the empty parameter-type-list must be spelled "void"; a 2630 // typedef of void is not permitted. 2631 if (getLangOptions().CPlusPlus && 2632 Param->getType().getUnqualifiedType() != Context.VoidTy) 2633 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2634 // FIXME: Leaks decl? 2635 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2636 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2637 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2638 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2639 Param->setDeclContext(NewFD); 2640 Params.push_back(Param); 2641 } 2642 } 2643 2644 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2645 // When we're declaring a function with a typedef, typeof, etc as in the 2646 // following example, we'll need to synthesize (unnamed) 2647 // parameters for use in the declaration. 2648 // 2649 // @code 2650 // typedef void fn(int); 2651 // fn f; 2652 // @endcode 2653 2654 // Synthesize a parameter for each argument type. 2655 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2656 AE = FT->arg_type_end(); AI != AE; ++AI) { 2657 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2658 SourceLocation(), 0, 2659 *AI, /*DInfo=*/0, 2660 VarDecl::None, 0); 2661 Param->setImplicit(); 2662 Params.push_back(Param); 2663 } 2664 } else { 2665 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2666 "Should not need args for typedef of non-prototype fn"); 2667 } 2668 // Finally, we know we have the right number of parameters, install them. 2669 NewFD->setParams(Context, Params.data(), Params.size()); 2670 2671 // If name lookup finds a previous declaration that is not in the 2672 // same scope as the new declaration, this may still be an 2673 // acceptable redeclaration. 2674 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2675 !(NewFD->hasLinkage() && 2676 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2677 PrevDecl = 0; 2678 2679 // Perform semantic checking on the function declaration. 2680 bool OverloadableAttrRequired = false; // FIXME: HACK! 2681 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2682 /*FIXME:*/OverloadableAttrRequired); 2683 2684 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2685 // An out-of-line member function declaration must also be a 2686 // definition (C++ [dcl.meaning]p1). 2687 if (!IsFunctionDefinition && !isFriend) { 2688 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2689 << D.getCXXScopeSpec().getRange(); 2690 NewFD->setInvalidDecl(); 2691 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2692 // The user tried to provide an out-of-line definition for a 2693 // function that is a member of a class or namespace, but there 2694 // was no such member function declared (C++ [class.mfct]p2, 2695 // C++ [namespace.memdef]p2). For example: 2696 // 2697 // class X { 2698 // void f() const; 2699 // }; 2700 // 2701 // void X::f() { } // ill-formed 2702 // 2703 // Complain about this problem, and attempt to suggest close 2704 // matches (e.g., those that differ only in cv-qualifiers and 2705 // whether the parameter types are references). 2706 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2707 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2708 NewFD->setInvalidDecl(); 2709 2710 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2711 true); 2712 assert(!Prev.isAmbiguous() && 2713 "Cannot have an ambiguity in previous-declaration lookup"); 2714 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2715 Func != FuncEnd; ++Func) { 2716 if (isa<FunctionDecl>(*Func) && 2717 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2718 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2719 } 2720 2721 PrevDecl = 0; 2722 } 2723 } 2724 2725 // Handle attributes. We need to have merged decls when handling attributes 2726 // (for example to check for conflicts, etc). 2727 // FIXME: This needs to happen before we merge declarations. Then, 2728 // let attribute merging cope with attribute conflicts. 2729 ProcessDeclAttributes(S, NewFD, D); 2730 2731 // attributes declared post-definition are currently ignored 2732 if (Redeclaration && PrevDecl) { 2733 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2734 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2735 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2736 Diag(Def->getLocation(), diag::note_previous_definition); 2737 } 2738 } 2739 2740 AddKnownFunctionAttributes(NewFD); 2741 2742 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2743 // If a function name is overloadable in C, then every function 2744 // with that name must be marked "overloadable". 2745 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2746 << Redeclaration << NewFD; 2747 if (PrevDecl) 2748 Diag(PrevDecl->getLocation(), 2749 diag::note_attribute_overloadable_prev_overload); 2750 NewFD->addAttr(::new (Context) OverloadableAttr()); 2751 } 2752 2753 // If this is a locally-scoped extern C function, update the 2754 // map of such names. 2755 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2756 && !NewFD->isInvalidDecl()) 2757 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2758 2759 // Set this FunctionDecl's range up to the right paren. 2760 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2761 2762 if (FunctionTemplate && NewFD->isInvalidDecl()) 2763 FunctionTemplate->setInvalidDecl(); 2764 2765 if (FunctionTemplate) 2766 return FunctionTemplate; 2767 2768 return NewFD; 2769} 2770 2771/// \brief Perform semantic checking of a new function declaration. 2772/// 2773/// Performs semantic analysis of the new function declaration 2774/// NewFD. This routine performs all semantic checking that does not 2775/// require the actual declarator involved in the declaration, and is 2776/// used both for the declaration of functions as they are parsed 2777/// (called via ActOnDeclarator) and for the declaration of functions 2778/// that have been instantiated via C++ template instantiation (called 2779/// via InstantiateDecl). 2780/// 2781/// This sets NewFD->isInvalidDecl() to true if there was an error. 2782void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2783 bool &Redeclaration, 2784 bool &OverloadableAttrRequired) { 2785 // If NewFD is already known erroneous, don't do any of this checking. 2786 if (NewFD->isInvalidDecl()) 2787 return; 2788 2789 if (NewFD->getResultType()->isVariablyModifiedType()) { 2790 // Functions returning a variably modified type violate C99 6.7.5.2p2 2791 // because all functions have linkage. 2792 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2793 return NewFD->setInvalidDecl(); 2794 } 2795 2796 if (NewFD->isMain()) 2797 CheckMain(NewFD); 2798 2799 // Check for a previous declaration of this name. 2800 if (!PrevDecl && NewFD->isExternC()) { 2801 // Since we did not find anything by this name and we're declaring 2802 // an extern "C" function, look for a non-visible extern "C" 2803 // declaration with the same name. 2804 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2805 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2806 if (Pos != LocallyScopedExternalDecls.end()) 2807 PrevDecl = Pos->second; 2808 } 2809 2810 // Merge or overload the declaration with an existing declaration of 2811 // the same name, if appropriate. 2812 if (PrevDecl) { 2813 // Determine whether NewFD is an overload of PrevDecl or 2814 // a declaration that requires merging. If it's an overload, 2815 // there's no more work to do here; we'll just add the new 2816 // function to the scope. 2817 OverloadedFunctionDecl::function_iterator MatchedDecl; 2818 2819 if (!getLangOptions().CPlusPlus && 2820 AllowOverloadingOfFunction(PrevDecl, Context)) { 2821 OverloadableAttrRequired = true; 2822 2823 // Functions marked "overloadable" must have a prototype (that 2824 // we can't get through declaration merging). 2825 if (!NewFD->getType()->getAsFunctionProtoType()) { 2826 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2827 << NewFD; 2828 Redeclaration = true; 2829 2830 // Turn this into a variadic function with no parameters. 2831 QualType R = Context.getFunctionType( 2832 NewFD->getType()->getAsFunctionType()->getResultType(), 2833 0, 0, true, 0); 2834 NewFD->setType(R); 2835 return NewFD->setInvalidDecl(); 2836 } 2837 } 2838 2839 if (PrevDecl && 2840 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2841 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2842 Redeclaration = true; 2843 Decl *OldDecl = PrevDecl; 2844 2845 // If PrevDecl was an overloaded function, extract the 2846 // FunctionDecl that matched. 2847 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2848 OldDecl = *MatchedDecl; 2849 2850 // NewFD and OldDecl represent declarations that need to be 2851 // merged. 2852 if (MergeFunctionDecl(NewFD, OldDecl)) 2853 return NewFD->setInvalidDecl(); 2854 2855 if (FunctionTemplateDecl *OldTemplateDecl 2856 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2857 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2858 else { 2859 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2860 NewFD->setAccess(OldDecl->getAccess()); 2861 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2862 } 2863 } 2864 } 2865 2866 // Semantic checking for this function declaration (in isolation). 2867 if (getLangOptions().CPlusPlus) { 2868 // C++-specific checks. 2869 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2870 CheckConstructor(Constructor); 2871 } else if (isa<CXXDestructorDecl>(NewFD)) { 2872 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2873 QualType ClassType = Context.getTypeDeclType(Record); 2874 if (!ClassType->isDependentType()) { 2875 DeclarationName Name 2876 = Context.DeclarationNames.getCXXDestructorName( 2877 Context.getCanonicalType(ClassType)); 2878 if (NewFD->getDeclName() != Name) { 2879 Diag(NewFD->getLocation(), diag::err_destructor_name); 2880 return NewFD->setInvalidDecl(); 2881 } 2882 } 2883 Record->setUserDeclaredDestructor(true); 2884 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2885 // user-defined destructor. 2886 Record->setPOD(false); 2887 2888 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2889 // declared destructor. 2890 // FIXME: C++0x: don't do this for "= default" destructors 2891 Record->setHasTrivialDestructor(false); 2892 } else if (CXXConversionDecl *Conversion 2893 = dyn_cast<CXXConversionDecl>(NewFD)) 2894 ActOnConversionDeclarator(Conversion); 2895 2896 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2897 if (NewFD->isOverloadedOperator() && 2898 CheckOverloadedOperatorDeclaration(NewFD)) 2899 return NewFD->setInvalidDecl(); 2900 2901 // In C++, check default arguments now that we have merged decls. Unless 2902 // the lexical context is the class, because in this case this is done 2903 // during delayed parsing anyway. 2904 if (!CurContext->isRecord()) 2905 CheckCXXDefaultArguments(NewFD); 2906 } 2907} 2908 2909void Sema::CheckMain(FunctionDecl* FD) { 2910 // C++ [basic.start.main]p3: A program that declares main to be inline 2911 // or static is ill-formed. 2912 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2913 // shall not appear in a declaration of main. 2914 // static main is not an error under C99, but we should warn about it. 2915 bool isInline = FD->isInline(); 2916 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2917 if (isInline || isStatic) { 2918 unsigned diagID = diag::warn_unusual_main_decl; 2919 if (isInline || getLangOptions().CPlusPlus) 2920 diagID = diag::err_unusual_main_decl; 2921 2922 int which = isStatic + (isInline << 1) - 1; 2923 Diag(FD->getLocation(), diagID) << which; 2924 } 2925 2926 QualType T = FD->getType(); 2927 assert(T->isFunctionType() && "function decl is not of function type"); 2928 const FunctionType* FT = T->getAsFunctionType(); 2929 2930 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2931 // TODO: add a replacement fixit to turn the return type into 'int'. 2932 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2933 FD->setInvalidDecl(true); 2934 } 2935 2936 // Treat protoless main() as nullary. 2937 if (isa<FunctionNoProtoType>(FT)) return; 2938 2939 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2940 unsigned nparams = FTP->getNumArgs(); 2941 assert(FD->getNumParams() == nparams); 2942 2943 if (nparams > 3) { 2944 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2945 FD->setInvalidDecl(true); 2946 nparams = 3; 2947 } 2948 2949 // FIXME: a lot of the following diagnostics would be improved 2950 // if we had some location information about types. 2951 2952 QualType CharPP = 2953 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2954 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2955 2956 for (unsigned i = 0; i < nparams; ++i) { 2957 QualType AT = FTP->getArgType(i); 2958 2959 bool mismatch = true; 2960 2961 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2962 mismatch = false; 2963 else if (Expected[i] == CharPP) { 2964 // As an extension, the following forms are okay: 2965 // char const ** 2966 // char const * const * 2967 // char * const * 2968 2969 QualifierSet qs; 2970 const PointerType* PT; 2971 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 2972 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 2973 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 2974 qs.removeConst(); 2975 mismatch = !qs.empty(); 2976 } 2977 } 2978 2979 if (mismatch) { 2980 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 2981 // TODO: suggest replacing given type with expected type 2982 FD->setInvalidDecl(true); 2983 } 2984 } 2985 2986 if (nparams == 1 && !FD->isInvalidDecl()) { 2987 Diag(FD->getLocation(), diag::warn_main_one_arg); 2988 } 2989} 2990 2991bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2992 // FIXME: Need strict checking. In C89, we need to check for 2993 // any assignment, increment, decrement, function-calls, or 2994 // commas outside of a sizeof. In C99, it's the same list, 2995 // except that the aforementioned are allowed in unevaluated 2996 // expressions. Everything else falls under the 2997 // "may accept other forms of constant expressions" exception. 2998 // (We never end up here for C++, so the constant expression 2999 // rules there don't matter.) 3000 if (Init->isConstantInitializer(Context)) 3001 return false; 3002 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3003 << Init->getSourceRange(); 3004 return true; 3005} 3006 3007void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3008 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3009} 3010 3011/// AddInitializerToDecl - Adds the initializer Init to the 3012/// declaration dcl. If DirectInit is true, this is C++ direct 3013/// initialization rather than copy initialization. 3014void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3015 Decl *RealDecl = dcl.getAs<Decl>(); 3016 // If there is no declaration, there was an error parsing it. Just ignore 3017 // the initializer. 3018 if (RealDecl == 0) 3019 return; 3020 3021 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3022 // With declarators parsed the way they are, the parser cannot 3023 // distinguish between a normal initializer and a pure-specifier. 3024 // Thus this grotesque test. 3025 IntegerLiteral *IL; 3026 Expr *Init = static_cast<Expr *>(init.get()); 3027 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3028 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3029 if (Method->isVirtualAsWritten()) { 3030 Method->setPure(); 3031 3032 // A class is abstract if at least one function is pure virtual. 3033 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3034 } else if (!Method->isInvalidDecl()) { 3035 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3036 << Method->getDeclName() << Init->getSourceRange(); 3037 Method->setInvalidDecl(); 3038 } 3039 } else { 3040 Diag(Method->getLocation(), diag::err_member_function_initialization) 3041 << Method->getDeclName() << Init->getSourceRange(); 3042 Method->setInvalidDecl(); 3043 } 3044 return; 3045 } 3046 3047 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3048 if (!VDecl) { 3049 if (getLangOptions().CPlusPlus && 3050 RealDecl->getLexicalDeclContext()->isRecord() && 3051 isa<NamedDecl>(RealDecl)) 3052 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3053 << cast<NamedDecl>(RealDecl)->getDeclName(); 3054 else 3055 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3056 RealDecl->setInvalidDecl(); 3057 return; 3058 } 3059 3060 if (!VDecl->getType()->isArrayType() && 3061 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3062 diag::err_typecheck_decl_incomplete_type)) { 3063 RealDecl->setInvalidDecl(); 3064 return; 3065 } 3066 3067 const VarDecl *Def = 0; 3068 if (VDecl->getDefinition(Def)) { 3069 Diag(VDecl->getLocation(), diag::err_redefinition) 3070 << VDecl->getDeclName(); 3071 Diag(Def->getLocation(), diag::note_previous_definition); 3072 VDecl->setInvalidDecl(); 3073 return; 3074 } 3075 3076 // Take ownership of the expression, now that we're sure we have somewhere 3077 // to put it. 3078 Expr *Init = init.takeAs<Expr>(); 3079 assert(Init && "missing initializer"); 3080 3081 // Get the decls type and save a reference for later, since 3082 // CheckInitializerTypes may change it. 3083 QualType DclT = VDecl->getType(), SavT = DclT; 3084 if (VDecl->isBlockVarDecl()) { 3085 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3086 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3087 VDecl->setInvalidDecl(); 3088 } else if (!VDecl->isInvalidDecl()) { 3089 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3090 VDecl->getDeclName(), DirectInit)) 3091 VDecl->setInvalidDecl(); 3092 3093 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3094 // Don't check invalid declarations to avoid emitting useless diagnostics. 3095 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3096 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3097 CheckForConstantInitializer(Init, DclT); 3098 } 3099 } 3100 } else if (VDecl->isStaticDataMember() && 3101 VDecl->getLexicalDeclContext()->isRecord()) { 3102 // This is an in-class initialization for a static data member, e.g., 3103 // 3104 // struct S { 3105 // static const int value = 17; 3106 // }; 3107 3108 // Attach the initializer 3109 VDecl->setInit(Context, Init); 3110 3111 // C++ [class.mem]p4: 3112 // A member-declarator can contain a constant-initializer only 3113 // if it declares a static member (9.4) of const integral or 3114 // const enumeration type, see 9.4.2. 3115 QualType T = VDecl->getType(); 3116 if (!T->isDependentType() && 3117 (!Context.getCanonicalType(T).isConstQualified() || 3118 !T->isIntegralType())) { 3119 Diag(VDecl->getLocation(), diag::err_member_initialization) 3120 << VDecl->getDeclName() << Init->getSourceRange(); 3121 VDecl->setInvalidDecl(); 3122 } else { 3123 // C++ [class.static.data]p4: 3124 // If a static data member is of const integral or const 3125 // enumeration type, its declaration in the class definition 3126 // can specify a constant-initializer which shall be an 3127 // integral constant expression (5.19). 3128 if (!Init->isTypeDependent() && 3129 !Init->getType()->isIntegralType()) { 3130 // We have a non-dependent, non-integral or enumeration type. 3131 Diag(Init->getSourceRange().getBegin(), 3132 diag::err_in_class_initializer_non_integral_type) 3133 << Init->getType() << Init->getSourceRange(); 3134 VDecl->setInvalidDecl(); 3135 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3136 // Check whether the expression is a constant expression. 3137 llvm::APSInt Value; 3138 SourceLocation Loc; 3139 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3140 Diag(Loc, diag::err_in_class_initializer_non_constant) 3141 << Init->getSourceRange(); 3142 VDecl->setInvalidDecl(); 3143 } else if (!VDecl->getType()->isDependentType()) 3144 ImpCastExprToType(Init, VDecl->getType()); 3145 } 3146 } 3147 } else if (VDecl->isFileVarDecl()) { 3148 if (VDecl->getStorageClass() == VarDecl::Extern) 3149 Diag(VDecl->getLocation(), diag::warn_extern_init); 3150 if (!VDecl->isInvalidDecl()) 3151 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3152 VDecl->getDeclName(), DirectInit)) 3153 VDecl->setInvalidDecl(); 3154 3155 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3156 // Don't check invalid declarations to avoid emitting useless diagnostics. 3157 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3158 // C99 6.7.8p4. All file scoped initializers need to be constant. 3159 CheckForConstantInitializer(Init, DclT); 3160 } 3161 } 3162 // If the type changed, it means we had an incomplete type that was 3163 // completed by the initializer. For example: 3164 // int ary[] = { 1, 3, 5 }; 3165 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3166 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3167 VDecl->setType(DclT); 3168 Init->setType(DclT); 3169 } 3170 3171 Init = MaybeCreateCXXExprWithTemporaries(Init, 3172 /*ShouldDestroyTemporaries=*/true); 3173 // Attach the initializer to the decl. 3174 VDecl->setInit(Context, Init); 3175 3176 // If the previous declaration of VDecl was a tentative definition, 3177 // remove it from the set of tentative definitions. 3178 if (VDecl->getPreviousDeclaration() && 3179 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3180 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3181 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3182 } 3183 3184 return; 3185} 3186 3187void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3188 bool TypeContainsUndeducedAuto) { 3189 Decl *RealDecl = dcl.getAs<Decl>(); 3190 3191 // If there is no declaration, there was an error parsing it. Just ignore it. 3192 if (RealDecl == 0) 3193 return; 3194 3195 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3196 QualType Type = Var->getType(); 3197 3198 // Record tentative definitions. 3199 if (Var->isTentativeDefinition(Context)) { 3200 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3201 InsertPair = 3202 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3203 3204 // Keep the latest definition in the map. If we see 'int i; int i;' we 3205 // want the second one in the map. 3206 InsertPair.first->second = Var; 3207 3208 // However, for the list, we don't care about the order, just make sure 3209 // that there are no dupes for a given declaration name. 3210 if (InsertPair.second) 3211 TentativeDefinitionList.push_back(Var->getDeclName()); 3212 } 3213 3214 // C++ [dcl.init.ref]p3: 3215 // The initializer can be omitted for a reference only in a 3216 // parameter declaration (8.3.5), in the declaration of a 3217 // function return type, in the declaration of a class member 3218 // within its class declaration (9.2), and where the extern 3219 // specifier is explicitly used. 3220 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3221 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3222 << Var->getDeclName() 3223 << SourceRange(Var->getLocation(), Var->getLocation()); 3224 Var->setInvalidDecl(); 3225 return; 3226 } 3227 3228 // C++0x [dcl.spec.auto]p3 3229 if (TypeContainsUndeducedAuto) { 3230 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3231 << Var->getDeclName() << Type; 3232 Var->setInvalidDecl(); 3233 return; 3234 } 3235 3236 // C++ [dcl.init]p9: 3237 // If no initializer is specified for an object, and the object 3238 // is of (possibly cv-qualified) non-POD class type (or array 3239 // thereof), the object shall be default-initialized; if the 3240 // object is of const-qualified type, the underlying class type 3241 // shall have a user-declared default constructor. 3242 // 3243 // FIXME: Diagnose the "user-declared default constructor" bit. 3244 if (getLangOptions().CPlusPlus) { 3245 QualType InitType = Type; 3246 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3247 InitType = Array->getElementType(); 3248 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3249 InitType->isRecordType() && !InitType->isDependentType()) { 3250 if (!RequireCompleteType(Var->getLocation(), InitType, 3251 diag::err_invalid_incomplete_type_use)) { 3252 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3253 3254 CXXConstructorDecl *Constructor 3255 = PerformInitializationByConstructor(InitType, 3256 MultiExprArg(*this, 0, 0), 3257 Var->getLocation(), 3258 SourceRange(Var->getLocation(), 3259 Var->getLocation()), 3260 Var->getDeclName(), 3261 IK_Default, 3262 ConstructorArgs); 3263 3264 // FIXME: Location info for the variable initialization? 3265 if (!Constructor) 3266 Var->setInvalidDecl(); 3267 else { 3268 // FIXME: Cope with initialization of arrays 3269 if (!Constructor->isTrivial() && 3270 InitializeVarWithConstructor(Var, Constructor, InitType, 3271 move_arg(ConstructorArgs))) 3272 Var->setInvalidDecl(); 3273 3274 FinalizeVarWithDestructor(Var, InitType); 3275 } 3276 } 3277 } 3278 } 3279 3280#if 0 3281 // FIXME: Temporarily disabled because we are not properly parsing 3282 // linkage specifications on declarations, e.g., 3283 // 3284 // extern "C" const CGPoint CGPointerZero; 3285 // 3286 // C++ [dcl.init]p9: 3287 // 3288 // If no initializer is specified for an object, and the 3289 // object is of (possibly cv-qualified) non-POD class type (or 3290 // array thereof), the object shall be default-initialized; if 3291 // the object is of const-qualified type, the underlying class 3292 // type shall have a user-declared default 3293 // constructor. Otherwise, if no initializer is specified for 3294 // an object, the object and its subobjects, if any, have an 3295 // indeterminate initial value; if the object or any of its 3296 // subobjects are of const-qualified type, the program is 3297 // ill-formed. 3298 // 3299 // This isn't technically an error in C, so we don't diagnose it. 3300 // 3301 // FIXME: Actually perform the POD/user-defined default 3302 // constructor check. 3303 if (getLangOptions().CPlusPlus && 3304 Context.getCanonicalType(Type).isConstQualified() && 3305 !Var->hasExternalStorage()) 3306 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3307 << Var->getName() 3308 << SourceRange(Var->getLocation(), Var->getLocation()); 3309#endif 3310 } 3311} 3312 3313Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3314 DeclPtrTy *Group, 3315 unsigned NumDecls) { 3316 llvm::SmallVector<Decl*, 8> Decls; 3317 3318 if (DS.isTypeSpecOwned()) 3319 Decls.push_back((Decl*)DS.getTypeRep()); 3320 3321 for (unsigned i = 0; i != NumDecls; ++i) 3322 if (Decl *D = Group[i].getAs<Decl>()) 3323 Decls.push_back(D); 3324 3325 // Perform semantic analysis that depends on having fully processed both 3326 // the declarator and initializer. 3327 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3328 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3329 if (!IDecl) 3330 continue; 3331 QualType T = IDecl->getType(); 3332 3333 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3334 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3335 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3336 if (!IDecl->isInvalidDecl() && 3337 RequireCompleteType(IDecl->getLocation(), T, 3338 diag::err_typecheck_decl_incomplete_type)) 3339 IDecl->setInvalidDecl(); 3340 } 3341 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3342 // object that has file scope without an initializer, and without a 3343 // storage-class specifier or with the storage-class specifier "static", 3344 // constitutes a tentative definition. Note: A tentative definition with 3345 // external linkage is valid (C99 6.2.2p5). 3346 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3347 if (const IncompleteArrayType *ArrayT 3348 = Context.getAsIncompleteArrayType(T)) { 3349 if (RequireCompleteType(IDecl->getLocation(), 3350 ArrayT->getElementType(), 3351 diag::err_illegal_decl_array_incomplete_type)) 3352 IDecl->setInvalidDecl(); 3353 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3354 // C99 6.9.2p3: If the declaration of an identifier for an object is 3355 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3356 // declared type shall not be an incomplete type. 3357 // NOTE: code such as the following 3358 // static struct s; 3359 // struct s { int a; }; 3360 // is accepted by gcc. Hence here we issue a warning instead of 3361 // an error and we do not invalidate the static declaration. 3362 // NOTE: to avoid multiple warnings, only check the first declaration. 3363 if (IDecl->getPreviousDeclaration() == 0) 3364 RequireCompleteType(IDecl->getLocation(), T, 3365 diag::ext_typecheck_decl_incomplete_type); 3366 } 3367 } 3368 } 3369 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3370 Decls.data(), Decls.size())); 3371} 3372 3373 3374/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3375/// to introduce parameters into function prototype scope. 3376Sema::DeclPtrTy 3377Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3378 const DeclSpec &DS = D.getDeclSpec(); 3379 3380 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3381 VarDecl::StorageClass StorageClass = VarDecl::None; 3382 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3383 StorageClass = VarDecl::Register; 3384 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3385 Diag(DS.getStorageClassSpecLoc(), 3386 diag::err_invalid_storage_class_in_func_decl); 3387 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3388 } 3389 3390 if (D.getDeclSpec().isThreadSpecified()) 3391 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3392 3393 DiagnoseFunctionSpecifiers(D); 3394 3395 // Check that there are no default arguments inside the type of this 3396 // parameter (C++ only). 3397 if (getLangOptions().CPlusPlus) 3398 CheckExtraCXXDefaultArguments(D); 3399 3400 DeclaratorInfo *DInfo = 0; 3401 TagDecl *OwnedDecl = 0; 3402 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3403 &OwnedDecl); 3404 3405 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3406 // C++ [dcl.fct]p6: 3407 // Types shall not be defined in return or parameter types. 3408 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3409 << Context.getTypeDeclType(OwnedDecl); 3410 } 3411 3412 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3413 // Can this happen for params? We already checked that they don't conflict 3414 // among each other. Here they can only shadow globals, which is ok. 3415 IdentifierInfo *II = D.getIdentifier(); 3416 if (II) { 3417 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3418 if (PrevDecl->isTemplateParameter()) { 3419 // Maybe we will complain about the shadowed template parameter. 3420 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3421 // Just pretend that we didn't see the previous declaration. 3422 PrevDecl = 0; 3423 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3424 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3425 3426 // Recover by removing the name 3427 II = 0; 3428 D.SetIdentifier(0, D.getIdentifierLoc()); 3429 } 3430 } 3431 } 3432 3433 // Parameters can not be abstract class types. 3434 // For record types, this is done by the AbstractClassUsageDiagnoser once 3435 // the class has been completely parsed. 3436 if (!CurContext->isRecord() && 3437 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3438 diag::err_abstract_type_in_decl, 3439 AbstractParamType)) 3440 D.setInvalidType(true); 3441 3442 QualType T = adjustParameterType(parmDeclType); 3443 3444 ParmVarDecl *New; 3445 if (T == parmDeclType) // parameter type did not need adjustment 3446 New = ParmVarDecl::Create(Context, CurContext, 3447 D.getIdentifierLoc(), II, 3448 parmDeclType, DInfo, StorageClass, 3449 0); 3450 else // keep track of both the adjusted and unadjusted types 3451 New = OriginalParmVarDecl::Create(Context, CurContext, 3452 D.getIdentifierLoc(), II, T, DInfo, 3453 parmDeclType, StorageClass, 0); 3454 3455 if (D.isInvalidType()) 3456 New->setInvalidDecl(); 3457 3458 // Parameter declarators cannot be interface types. All ObjC objects are 3459 // passed by reference. 3460 if (T->isObjCInterfaceType()) { 3461 Diag(D.getIdentifierLoc(), 3462 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3463 New->setInvalidDecl(); 3464 } 3465 3466 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3467 if (D.getCXXScopeSpec().isSet()) { 3468 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3469 << D.getCXXScopeSpec().getRange(); 3470 New->setInvalidDecl(); 3471 } 3472 3473 // Add the parameter declaration into this scope. 3474 S->AddDecl(DeclPtrTy::make(New)); 3475 if (II) 3476 IdResolver.AddDecl(New); 3477 3478 ProcessDeclAttributes(S, New, D); 3479 3480 if (New->hasAttr<BlocksAttr>()) { 3481 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3482 } 3483 return DeclPtrTy::make(New); 3484} 3485 3486void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3487 SourceLocation LocAfterDecls) { 3488 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3489 "Not a function declarator!"); 3490 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3491 3492 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3493 // for a K&R function. 3494 if (!FTI.hasPrototype) { 3495 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3496 --i; 3497 if (FTI.ArgInfo[i].Param == 0) { 3498 std::string Code = " int "; 3499 Code += FTI.ArgInfo[i].Ident->getName(); 3500 Code += ";\n"; 3501 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3502 << FTI.ArgInfo[i].Ident 3503 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3504 3505 // Implicitly declare the argument as type 'int' for lack of a better 3506 // type. 3507 DeclSpec DS; 3508 const char* PrevSpec; // unused 3509 unsigned DiagID; // unused 3510 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3511 PrevSpec, DiagID); 3512 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3513 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3514 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3515 } 3516 } 3517 } 3518} 3519 3520Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3521 Declarator &D) { 3522 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3523 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3524 "Not a function declarator!"); 3525 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3526 3527 if (FTI.hasPrototype) { 3528 // FIXME: Diagnose arguments without names in C. 3529 } 3530 3531 Scope *ParentScope = FnBodyScope->getParent(); 3532 3533 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3534 MultiTemplateParamsArg(*this), 3535 /*IsFunctionDefinition=*/true); 3536 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3537} 3538 3539Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3540 if (!D) 3541 return D; 3542 FunctionDecl *FD = 0; 3543 3544 if (FunctionTemplateDecl *FunTmpl 3545 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3546 FD = FunTmpl->getTemplatedDecl(); 3547 else 3548 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3549 3550 CurFunctionNeedsScopeChecking = false; 3551 3552 // See if this is a redefinition. 3553 const FunctionDecl *Definition; 3554 if (FD->getBody(Definition)) { 3555 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3556 Diag(Definition->getLocation(), diag::note_previous_definition); 3557 } 3558 3559 // Builtin functions cannot be defined. 3560 if (unsigned BuiltinID = FD->getBuiltinID()) { 3561 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3562 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3563 FD->setInvalidDecl(); 3564 } 3565 } 3566 3567 // The return type of a function definition must be complete 3568 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3569 QualType ResultType = FD->getResultType(); 3570 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3571 !FD->isInvalidDecl() && 3572 RequireCompleteType(FD->getLocation(), ResultType, 3573 diag::err_func_def_incomplete_result)) 3574 FD->setInvalidDecl(); 3575 3576 // GNU warning -Wmissing-prototypes: 3577 // Warn if a global function is defined without a previous 3578 // prototype declaration. This warning is issued even if the 3579 // definition itself provides a prototype. The aim is to detect 3580 // global functions that fail to be declared in header files. 3581 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3582 !FD->isMain()) { 3583 bool MissingPrototype = true; 3584 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3585 Prev; Prev = Prev->getPreviousDeclaration()) { 3586 // Ignore any declarations that occur in function or method 3587 // scope, because they aren't visible from the header. 3588 if (Prev->getDeclContext()->isFunctionOrMethod()) 3589 continue; 3590 3591 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3592 break; 3593 } 3594 3595 if (MissingPrototype) 3596 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3597 } 3598 3599 if (FnBodyScope) 3600 PushDeclContext(FnBodyScope, FD); 3601 3602 // Check the validity of our function parameters 3603 CheckParmsForFunctionDef(FD); 3604 3605 // Introduce our parameters into the function scope 3606 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3607 ParmVarDecl *Param = FD->getParamDecl(p); 3608 Param->setOwningFunction(FD); 3609 3610 // If this has an identifier, add it to the scope stack. 3611 if (Param->getIdentifier() && FnBodyScope) 3612 PushOnScopeChains(Param, FnBodyScope); 3613 } 3614 3615 // Checking attributes of current function definition 3616 // dllimport attribute. 3617 if (FD->getAttr<DLLImportAttr>() && 3618 (!FD->getAttr<DLLExportAttr>())) { 3619 // dllimport attribute cannot be applied to definition. 3620 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3621 Diag(FD->getLocation(), 3622 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3623 << "dllimport"; 3624 FD->setInvalidDecl(); 3625 return DeclPtrTy::make(FD); 3626 } else { 3627 // If a symbol previously declared dllimport is later defined, the 3628 // attribute is ignored in subsequent references, and a warning is 3629 // emitted. 3630 Diag(FD->getLocation(), 3631 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3632 << FD->getNameAsCString() << "dllimport"; 3633 } 3634 } 3635 return DeclPtrTy::make(FD); 3636} 3637 3638Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3639 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3640} 3641 3642Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3643 bool IsInstantiation) { 3644 Decl *dcl = D.getAs<Decl>(); 3645 Stmt *Body = BodyArg.takeAs<Stmt>(); 3646 3647 FunctionDecl *FD = 0; 3648 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3649 if (FunTmpl) 3650 FD = FunTmpl->getTemplatedDecl(); 3651 else 3652 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3653 3654 if (FD) { 3655 FD->setBody(Body); 3656 if (FD->isMain()) 3657 // C and C++ allow for main to automagically return 0. 3658 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3659 FD->setHasImplicitReturnZero(true); 3660 else 3661 CheckFallThroughForFunctionDef(FD, Body); 3662 3663 if (!FD->isInvalidDecl()) 3664 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3665 3666 // C++ [basic.def.odr]p2: 3667 // [...] A virtual member function is used if it is not pure. [...] 3668 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3669 if (Method->isVirtual() && !Method->isPure()) 3670 MarkDeclarationReferenced(Method->getLocation(), Method); 3671 3672 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3673 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3674 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3675 MD->setBody(Body); 3676 CheckFallThroughForFunctionDef(MD, Body); 3677 MD->setEndLoc(Body->getLocEnd()); 3678 3679 if (!MD->isInvalidDecl()) 3680 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3681 } else { 3682 Body->Destroy(Context); 3683 return DeclPtrTy(); 3684 } 3685 if (!IsInstantiation) 3686 PopDeclContext(); 3687 3688 // Verify and clean out per-function state. 3689 3690 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3691 3692 // Check goto/label use. 3693 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3694 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3695 LabelStmt *L = I->second; 3696 3697 // Verify that we have no forward references left. If so, there was a goto 3698 // or address of a label taken, but no definition of it. Label fwd 3699 // definitions are indicated with a null substmt. 3700 if (L->getSubStmt() != 0) 3701 continue; 3702 3703 // Emit error. 3704 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3705 3706 // At this point, we have gotos that use the bogus label. Stitch it into 3707 // the function body so that they aren't leaked and that the AST is well 3708 // formed. 3709 if (Body == 0) { 3710 // The whole function wasn't parsed correctly, just delete this. 3711 L->Destroy(Context); 3712 continue; 3713 } 3714 3715 // Otherwise, the body is valid: we want to stitch the label decl into the 3716 // function somewhere so that it is properly owned and so that the goto 3717 // has a valid target. Do this by creating a new compound stmt with the 3718 // label in it. 3719 3720 // Give the label a sub-statement. 3721 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3722 3723 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3724 cast<CXXTryStmt>(Body)->getTryBlock() : 3725 cast<CompoundStmt>(Body); 3726 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3727 Elements.push_back(L); 3728 Compound->setStmts(Context, &Elements[0], Elements.size()); 3729 } 3730 FunctionLabelMap.clear(); 3731 3732 if (!Body) return D; 3733 3734 // Verify that that gotos and switch cases don't jump into scopes illegally. 3735 if (CurFunctionNeedsScopeChecking) 3736 DiagnoseInvalidJumps(Body); 3737 3738 // C++ constructors that have function-try-blocks can't have return 3739 // statements in the handlers of that block. (C++ [except.handle]p14) 3740 // Verify this. 3741 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3742 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3743 3744 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3745 computeBaseOrMembersToDestroy(Destructor); 3746 return D; 3747} 3748 3749/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3750/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3751NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3752 IdentifierInfo &II, Scope *S) { 3753 // Before we produce a declaration for an implicitly defined 3754 // function, see whether there was a locally-scoped declaration of 3755 // this name as a function or variable. If so, use that 3756 // (non-visible) declaration, and complain about it. 3757 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3758 = LocallyScopedExternalDecls.find(&II); 3759 if (Pos != LocallyScopedExternalDecls.end()) { 3760 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3761 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3762 return Pos->second; 3763 } 3764 3765 // Extension in C99. Legal in C90, but warn about it. 3766 if (getLangOptions().C99) 3767 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3768 else 3769 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3770 3771 // FIXME: handle stuff like: 3772 // void foo() { extern float X(); } 3773 // void bar() { X(); } <-- implicit decl for X in another scope. 3774 3775 // Set a Declarator for the implicit definition: int foo(); 3776 const char *Dummy; 3777 DeclSpec DS; 3778 unsigned DiagID; 3779 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3780 Error = Error; // Silence warning. 3781 assert(!Error && "Error setting up implicit decl!"); 3782 Declarator D(DS, Declarator::BlockContext); 3783 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3784 0, 0, false, SourceLocation(), 3785 false, 0,0,0, Loc, Loc, D), 3786 SourceLocation()); 3787 D.SetIdentifier(&II, Loc); 3788 3789 // Insert this function into translation-unit scope. 3790 3791 DeclContext *PrevDC = CurContext; 3792 CurContext = Context.getTranslationUnitDecl(); 3793 3794 FunctionDecl *FD = 3795 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3796 FD->setImplicit(); 3797 3798 CurContext = PrevDC; 3799 3800 AddKnownFunctionAttributes(FD); 3801 3802 return FD; 3803} 3804 3805/// \brief Adds any function attributes that we know a priori based on 3806/// the declaration of this function. 3807/// 3808/// These attributes can apply both to implicitly-declared builtins 3809/// (like __builtin___printf_chk) or to library-declared functions 3810/// like NSLog or printf. 3811void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3812 if (FD->isInvalidDecl()) 3813 return; 3814 3815 // If this is a built-in function, map its builtin attributes to 3816 // actual attributes. 3817 if (unsigned BuiltinID = FD->getBuiltinID()) { 3818 // Handle printf-formatting attributes. 3819 unsigned FormatIdx; 3820 bool HasVAListArg; 3821 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3822 if (!FD->getAttr<FormatAttr>()) 3823 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3824 HasVAListArg ? 0 : FormatIdx + 2)); 3825 } 3826 3827 // Mark const if we don't care about errno and that is the only 3828 // thing preventing the function from being const. This allows 3829 // IRgen to use LLVM intrinsics for such functions. 3830 if (!getLangOptions().MathErrno && 3831 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3832 if (!FD->getAttr<ConstAttr>()) 3833 FD->addAttr(::new (Context) ConstAttr()); 3834 } 3835 3836 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3837 FD->addAttr(::new (Context) NoReturnAttr()); 3838 } 3839 3840 IdentifierInfo *Name = FD->getIdentifier(); 3841 if (!Name) 3842 return; 3843 if ((!getLangOptions().CPlusPlus && 3844 FD->getDeclContext()->isTranslationUnit()) || 3845 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3846 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3847 LinkageSpecDecl::lang_c)) { 3848 // Okay: this could be a libc/libm/Objective-C function we know 3849 // about. 3850 } else 3851 return; 3852 3853 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3854 // FIXME: NSLog and NSLogv should be target specific 3855 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3856 // FIXME: We known better than our headers. 3857 const_cast<FormatAttr *>(Format)->setType("printf"); 3858 } else 3859 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3860 Name->isStr("NSLogv") ? 0 : 2)); 3861 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3862 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3863 // target-specific builtins, perhaps? 3864 if (!FD->getAttr<FormatAttr>()) 3865 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3866 Name->isStr("vasprintf") ? 0 : 3)); 3867 } 3868} 3869 3870TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3871 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3872 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3873 3874 // Scope manipulation handled by caller. 3875 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3876 D.getIdentifierLoc(), 3877 D.getIdentifier(), 3878 T); 3879 3880 if (const TagType *TT = T->getAs<TagType>()) { 3881 TagDecl *TD = TT->getDecl(); 3882 3883 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3884 // keep track of the TypedefDecl. 3885 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3886 TD->setTypedefForAnonDecl(NewTD); 3887 } 3888 3889 if (D.isInvalidType()) 3890 NewTD->setInvalidDecl(); 3891 return NewTD; 3892} 3893 3894 3895/// \brief Determine whether a tag with a given kind is acceptable 3896/// as a redeclaration of the given tag declaration. 3897/// 3898/// \returns true if the new tag kind is acceptable, false otherwise. 3899bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3900 TagDecl::TagKind NewTag, 3901 SourceLocation NewTagLoc, 3902 const IdentifierInfo &Name) { 3903 // C++ [dcl.type.elab]p3: 3904 // The class-key or enum keyword present in the 3905 // elaborated-type-specifier shall agree in kind with the 3906 // declaration to which the name in theelaborated-type-specifier 3907 // refers. This rule also applies to the form of 3908 // elaborated-type-specifier that declares a class-name or 3909 // friend class since it can be construed as referring to the 3910 // definition of the class. Thus, in any 3911 // elaborated-type-specifier, the enum keyword shall be used to 3912 // refer to an enumeration (7.2), the union class-keyshall be 3913 // used to refer to a union (clause 9), and either the class or 3914 // struct class-key shall be used to refer to a class (clause 9) 3915 // declared using the class or struct class-key. 3916 TagDecl::TagKind OldTag = Previous->getTagKind(); 3917 if (OldTag == NewTag) 3918 return true; 3919 3920 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3921 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3922 // Warn about the struct/class tag mismatch. 3923 bool isTemplate = false; 3924 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3925 isTemplate = Record->getDescribedClassTemplate(); 3926 3927 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3928 << (NewTag == TagDecl::TK_class) 3929 << isTemplate << &Name 3930 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3931 OldTag == TagDecl::TK_class? "class" : "struct"); 3932 Diag(Previous->getLocation(), diag::note_previous_use); 3933 return true; 3934 } 3935 return false; 3936} 3937 3938/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3939/// former case, Name will be non-null. In the later case, Name will be null. 3940/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3941/// reference/declaration/definition of a tag. 3942Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3943 SourceLocation KWLoc, const CXXScopeSpec &SS, 3944 IdentifierInfo *Name, SourceLocation NameLoc, 3945 AttributeList *Attr, AccessSpecifier AS, 3946 MultiTemplateParamsArg TemplateParameterLists, 3947 bool &OwnedDecl, bool &IsDependent) { 3948 // If this is not a definition, it must have a name. 3949 assert((Name != 0 || TUK == TUK_Definition) && 3950 "Nameless record must be a definition!"); 3951 3952 OwnedDecl = false; 3953 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 3954 3955 if (TUK != TUK_Reference) { 3956 if (TemplateParameterList *TemplateParams 3957 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3958 (TemplateParameterList**)TemplateParameterLists.get(), 3959 TemplateParameterLists.size())) { 3960 if (TemplateParams->size() > 0) { 3961 // This is a declaration or definition of a class template (which may 3962 // be a member of another template). 3963 OwnedDecl = false; 3964 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 3965 SS, Name, NameLoc, Attr, 3966 TemplateParams, 3967 AS); 3968 TemplateParameterLists.release(); 3969 return Result.get(); 3970 } else { 3971 // FIXME: diagnose the extraneous 'template<>', once we recover 3972 // slightly better in ParseTemplate.cpp from bogus template 3973 // parameters. 3974 } 3975 } 3976 } 3977 3978 DeclContext *SearchDC = CurContext; 3979 DeclContext *DC = CurContext; 3980 NamedDecl *PrevDecl = 0; 3981 bool isStdBadAlloc = false; 3982 bool Invalid = false; 3983 3984 if (Name && SS.isNotEmpty()) { 3985 // We have a nested-name tag ('struct foo::bar'). 3986 3987 // Check for invalid 'foo::'. 3988 if (SS.isInvalid()) { 3989 Name = 0; 3990 goto CreateNewDecl; 3991 } 3992 3993 // If this is a friend or a reference to a class in a dependent 3994 // context, don't try to make a decl for it. 3995 if (TUK == TUK_Friend || TUK == TUK_Reference) { 3996 DC = computeDeclContext(SS, false); 3997 if (!DC) { 3998 IsDependent = true; 3999 return DeclPtrTy(); 4000 } 4001 } 4002 4003 if (RequireCompleteDeclContext(SS)) 4004 return DeclPtrTy::make((Decl *)0); 4005 4006 DC = computeDeclContext(SS, true); 4007 SearchDC = DC; 4008 // Look-up name inside 'foo::'. 4009 PrevDecl 4010 = dyn_cast_or_null<TagDecl>( 4011 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4012 4013 // A tag 'foo::bar' must already exist. 4014 if (PrevDecl == 0) { 4015 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4016 Name = 0; 4017 Invalid = true; 4018 goto CreateNewDecl; 4019 } 4020 } else if (Name) { 4021 // If this is a named struct, check to see if there was a previous forward 4022 // declaration or definition. 4023 // FIXME: We're looking into outer scopes here, even when we 4024 // shouldn't be. Doing so can result in ambiguities that we 4025 // shouldn't be diagnosing. 4026 LookupResult R = LookupName(S, Name, LookupTagName, 4027 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4028 if (R.isAmbiguous()) { 4029 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4030 // FIXME: This is not best way to recover from case like: 4031 // 4032 // struct S s; 4033 // 4034 // causes needless "incomplete type" error later. 4035 Name = 0; 4036 PrevDecl = 0; 4037 Invalid = true; 4038 } else 4039 PrevDecl = R; 4040 4041 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4042 // FIXME: This makes sure that we ignore the contexts associated 4043 // with C structs, unions, and enums when looking for a matching 4044 // tag declaration or definition. See the similar lookup tweak 4045 // in Sema::LookupName; is there a better way to deal with this? 4046 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4047 SearchDC = SearchDC->getParent(); 4048 } 4049 } 4050 4051 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4052 // Maybe we will complain about the shadowed template parameter. 4053 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4054 // Just pretend that we didn't see the previous declaration. 4055 PrevDecl = 0; 4056 } 4057 4058 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4059 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4060 // This is a declaration of or a reference to "std::bad_alloc". 4061 isStdBadAlloc = true; 4062 4063 if (!PrevDecl && StdBadAlloc) { 4064 // std::bad_alloc has been implicitly declared (but made invisible to 4065 // name lookup). Fill in this implicit declaration as the previous 4066 // declaration, so that the declarations get chained appropriately. 4067 PrevDecl = StdBadAlloc; 4068 } 4069 } 4070 4071 if (PrevDecl) { 4072 // Check whether the previous declaration is usable. 4073 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4074 4075 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4076 // If this is a use of a previous tag, or if the tag is already declared 4077 // in the same scope (so that the definition/declaration completes or 4078 // rementions the tag), reuse the decl. 4079 if (TUK == TUK_Reference || TUK == TUK_Friend || 4080 isDeclInScope(PrevDecl, SearchDC, S)) { 4081 // Make sure that this wasn't declared as an enum and now used as a 4082 // struct or something similar. 4083 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4084 bool SafeToContinue 4085 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4086 Kind != TagDecl::TK_enum); 4087 if (SafeToContinue) 4088 Diag(KWLoc, diag::err_use_with_wrong_tag) 4089 << Name 4090 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4091 PrevTagDecl->getKindName()); 4092 else 4093 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4094 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4095 4096 if (SafeToContinue) 4097 Kind = PrevTagDecl->getTagKind(); 4098 else { 4099 // Recover by making this an anonymous redefinition. 4100 Name = 0; 4101 PrevDecl = 0; 4102 Invalid = true; 4103 } 4104 } 4105 4106 if (!Invalid) { 4107 // If this is a use, just return the declaration we found. 4108 4109 // FIXME: In the future, return a variant or some other clue 4110 // for the consumer of this Decl to know it doesn't own it. 4111 // For our current ASTs this shouldn't be a problem, but will 4112 // need to be changed with DeclGroups. 4113 if (TUK == TUK_Reference) 4114 return DeclPtrTy::make(PrevDecl); 4115 4116 // If this is a friend, make sure we create the new 4117 // declaration in the appropriate semantic context. 4118 if (TUK == TUK_Friend) 4119 SearchDC = PrevDecl->getDeclContext(); 4120 4121 // Diagnose attempts to redefine a tag. 4122 if (TUK == TUK_Definition) { 4123 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4124 Diag(NameLoc, diag::err_redefinition) << Name; 4125 Diag(Def->getLocation(), diag::note_previous_definition); 4126 // If this is a redefinition, recover by making this 4127 // struct be anonymous, which will make any later 4128 // references get the previous definition. 4129 Name = 0; 4130 PrevDecl = 0; 4131 Invalid = true; 4132 } else { 4133 // If the type is currently being defined, complain 4134 // about a nested redefinition. 4135 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4136 if (Tag->isBeingDefined()) { 4137 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4138 Diag(PrevTagDecl->getLocation(), 4139 diag::note_previous_definition); 4140 Name = 0; 4141 PrevDecl = 0; 4142 Invalid = true; 4143 } 4144 } 4145 4146 // Okay, this is definition of a previously declared or referenced 4147 // tag PrevDecl. We're going to create a new Decl for it. 4148 } 4149 } 4150 // If we get here we have (another) forward declaration or we 4151 // have a definition. Just create a new decl. 4152 4153 } else { 4154 // If we get here, this is a definition of a new tag type in a nested 4155 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4156 // new decl/type. We set PrevDecl to NULL so that the entities 4157 // have distinct types. 4158 PrevDecl = 0; 4159 } 4160 // If we get here, we're going to create a new Decl. If PrevDecl 4161 // is non-NULL, it's a definition of the tag declared by 4162 // PrevDecl. If it's NULL, we have a new definition. 4163 } else { 4164 // PrevDecl is a namespace, template, or anything else 4165 // that lives in the IDNS_Tag identifier namespace. 4166 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4167 // The tag name clashes with a namespace name, issue an error and 4168 // recover by making this tag be anonymous. 4169 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4170 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4171 Name = 0; 4172 PrevDecl = 0; 4173 Invalid = true; 4174 } else { 4175 // The existing declaration isn't relevant to us; we're in a 4176 // new scope, so clear out the previous declaration. 4177 PrevDecl = 0; 4178 } 4179 } 4180 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4181 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4182 // C++ [basic.scope.pdecl]p5: 4183 // -- for an elaborated-type-specifier of the form 4184 // 4185 // class-key identifier 4186 // 4187 // if the elaborated-type-specifier is used in the 4188 // decl-specifier-seq or parameter-declaration-clause of a 4189 // function defined in namespace scope, the identifier is 4190 // declared as a class-name in the namespace that contains 4191 // the declaration; otherwise, except as a friend 4192 // declaration, the identifier is declared in the smallest 4193 // non-class, non-function-prototype scope that contains the 4194 // declaration. 4195 // 4196 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4197 // C structs and unions. 4198 // 4199 // GNU C also supports this behavior as part of its incomplete 4200 // enum types extension, while GNU C++ does not. 4201 // 4202 // Find the context where we'll be declaring the tag. 4203 // FIXME: We would like to maintain the current DeclContext as the 4204 // lexical context, 4205 while (SearchDC->isRecord()) 4206 SearchDC = SearchDC->getParent(); 4207 4208 // Find the scope where we'll be declaring the tag. 4209 while (S->isClassScope() || 4210 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4211 ((S->getFlags() & Scope::DeclScope) == 0) || 4212 (S->getEntity() && 4213 ((DeclContext *)S->getEntity())->isTransparentContext())) 4214 S = S->getParent(); 4215 4216 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4217 // C++ [namespace.memdef]p3: 4218 // If a friend declaration in a non-local class first declares a 4219 // class or function, the friend class or function is a member of 4220 // the innermost enclosing namespace. 4221 while (!SearchDC->isFileContext()) 4222 SearchDC = SearchDC->getParent(); 4223 4224 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4225 while (S->getEntity() != SearchDC) 4226 S = S->getParent(); 4227 } 4228 4229CreateNewDecl: 4230 4231 // If there is an identifier, use the location of the identifier as the 4232 // location of the decl, otherwise use the location of the struct/union 4233 // keyword. 4234 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4235 4236 // Otherwise, create a new declaration. If there is a previous 4237 // declaration of the same entity, the two will be linked via 4238 // PrevDecl. 4239 TagDecl *New; 4240 4241 if (Kind == TagDecl::TK_enum) { 4242 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4243 // enum X { A, B, C } D; D should chain to X. 4244 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4245 cast_or_null<EnumDecl>(PrevDecl)); 4246 // If this is an undefined enum, warn. 4247 if (TUK != TUK_Definition && !Invalid) { 4248 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4249 : diag::ext_forward_ref_enum; 4250 Diag(Loc, DK); 4251 } 4252 } else { 4253 // struct/union/class 4254 4255 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4256 // struct X { int A; } D; D should chain to X. 4257 if (getLangOptions().CPlusPlus) { 4258 // FIXME: Look for a way to use RecordDecl for simple structs. 4259 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4260 cast_or_null<CXXRecordDecl>(PrevDecl)); 4261 4262 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4263 StdBadAlloc = cast<CXXRecordDecl>(New); 4264 } else 4265 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4266 cast_or_null<RecordDecl>(PrevDecl)); 4267 } 4268 4269 if (Kind != TagDecl::TK_enum) { 4270 // Handle #pragma pack: if the #pragma pack stack has non-default 4271 // alignment, make up a packed attribute for this decl. These 4272 // attributes are checked when the ASTContext lays out the 4273 // structure. 4274 // 4275 // It is important for implementing the correct semantics that this 4276 // happen here (in act on tag decl). The #pragma pack stack is 4277 // maintained as a result of parser callbacks which can occur at 4278 // many points during the parsing of a struct declaration (because 4279 // the #pragma tokens are effectively skipped over during the 4280 // parsing of the struct). 4281 if (unsigned Alignment = getPragmaPackAlignment()) 4282 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4283 } 4284 4285 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4286 // C++ [dcl.typedef]p3: 4287 // [...] Similarly, in a given scope, a class or enumeration 4288 // shall not be declared with the same name as a typedef-name 4289 // that is declared in that scope and refers to a type other 4290 // than the class or enumeration itself. 4291 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4292 TypedefDecl *PrevTypedef = 0; 4293 if (Lookup.getKind() == LookupResult::Found) 4294 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4295 4296 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4297 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4298 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4299 Diag(Loc, diag::err_tag_definition_of_typedef) 4300 << Context.getTypeDeclType(New) 4301 << PrevTypedef->getUnderlyingType(); 4302 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4303 Invalid = true; 4304 } 4305 } 4306 4307 if (Invalid) 4308 New->setInvalidDecl(); 4309 4310 if (Attr) 4311 ProcessDeclAttributeList(S, New, Attr); 4312 4313 // If we're declaring or defining a tag in function prototype scope 4314 // in C, note that this type can only be used within the function. 4315 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4316 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4317 4318 // Set the lexical context. If the tag has a C++ scope specifier, the 4319 // lexical context will be different from the semantic context. 4320 New->setLexicalDeclContext(CurContext); 4321 4322 // Mark this as a friend decl if applicable. 4323 if (TUK == TUK_Friend) 4324 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4325 4326 // Set the access specifier. 4327 if (!Invalid && TUK != TUK_Friend) 4328 SetMemberAccessSpecifier(New, PrevDecl, AS); 4329 4330 if (TUK == TUK_Definition) 4331 New->startDefinition(); 4332 4333 // If this has an identifier, add it to the scope stack. 4334 if (TUK == TUK_Friend) { 4335 // We might be replacing an existing declaration in the lookup tables; 4336 // if so, borrow its access specifier. 4337 if (PrevDecl) 4338 New->setAccess(PrevDecl->getAccess()); 4339 4340 // Friend tag decls are visible in fairly strange ways. 4341 if (!CurContext->isDependentContext()) { 4342 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4343 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4344 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4345 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4346 } 4347 } else if (Name) { 4348 S = getNonFieldDeclScope(S); 4349 PushOnScopeChains(New, S); 4350 } else { 4351 CurContext->addDecl(New); 4352 } 4353 4354 // If this is the C FILE type, notify the AST context. 4355 if (IdentifierInfo *II = New->getIdentifier()) 4356 if (!New->isInvalidDecl() && 4357 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4358 II->isStr("FILE")) 4359 Context.setFILEDecl(New); 4360 4361 OwnedDecl = true; 4362 return DeclPtrTy::make(New); 4363} 4364 4365void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4366 AdjustDeclIfTemplate(TagD); 4367 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4368 4369 // Enter the tag context. 4370 PushDeclContext(S, Tag); 4371 4372 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4373 FieldCollector->StartClass(); 4374 4375 if (Record->getIdentifier()) { 4376 // C++ [class]p2: 4377 // [...] The class-name is also inserted into the scope of the 4378 // class itself; this is known as the injected-class-name. For 4379 // purposes of access checking, the injected-class-name is treated 4380 // as if it were a public member name. 4381 CXXRecordDecl *InjectedClassName 4382 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4383 CurContext, Record->getLocation(), 4384 Record->getIdentifier(), 4385 Record->getTagKeywordLoc(), 4386 Record); 4387 InjectedClassName->setImplicit(); 4388 InjectedClassName->setAccess(AS_public); 4389 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4390 InjectedClassName->setDescribedClassTemplate(Template); 4391 PushOnScopeChains(InjectedClassName, S); 4392 assert(InjectedClassName->isInjectedClassName() && 4393 "Broken injected-class-name"); 4394 } 4395 } 4396} 4397 4398void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4399 SourceLocation RBraceLoc) { 4400 AdjustDeclIfTemplate(TagD); 4401 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4402 Tag->setRBraceLoc(RBraceLoc); 4403 4404 if (isa<CXXRecordDecl>(Tag)) 4405 FieldCollector->FinishClass(); 4406 4407 // Exit this scope of this tag's definition. 4408 PopDeclContext(); 4409 4410 // Notify the consumer that we've defined a tag. 4411 Consumer.HandleTagDeclDefinition(Tag); 4412} 4413 4414// Note that FieldName may be null for anonymous bitfields. 4415bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4416 QualType FieldTy, const Expr *BitWidth, 4417 bool *ZeroWidth) { 4418 // Default to true; that shouldn't confuse checks for emptiness 4419 if (ZeroWidth) 4420 *ZeroWidth = true; 4421 4422 // C99 6.7.2.1p4 - verify the field type. 4423 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4424 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4425 // Handle incomplete types with specific error. 4426 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4427 return true; 4428 if (FieldName) 4429 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4430 << FieldName << FieldTy << BitWidth->getSourceRange(); 4431 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4432 << FieldTy << BitWidth->getSourceRange(); 4433 } 4434 4435 // If the bit-width is type- or value-dependent, don't try to check 4436 // it now. 4437 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4438 return false; 4439 4440 llvm::APSInt Value; 4441 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4442 return true; 4443 4444 if (Value != 0 && ZeroWidth) 4445 *ZeroWidth = false; 4446 4447 // Zero-width bitfield is ok for anonymous field. 4448 if (Value == 0 && FieldName) 4449 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4450 4451 if (Value.isSigned() && Value.isNegative()) { 4452 if (FieldName) 4453 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4454 << FieldName << Value.toString(10); 4455 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4456 << Value.toString(10); 4457 } 4458 4459 if (!FieldTy->isDependentType()) { 4460 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4461 if (Value.getZExtValue() > TypeSize) { 4462 if (FieldName) 4463 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4464 << FieldName << (unsigned)TypeSize; 4465 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4466 << (unsigned)TypeSize; 4467 } 4468 } 4469 4470 return false; 4471} 4472 4473/// ActOnField - Each field of a struct/union/class is passed into this in order 4474/// to create a FieldDecl object for it. 4475Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4476 SourceLocation DeclStart, 4477 Declarator &D, ExprTy *BitfieldWidth) { 4478 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4479 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4480 AS_public); 4481 return DeclPtrTy::make(Res); 4482} 4483 4484/// HandleField - Analyze a field of a C struct or a C++ data member. 4485/// 4486FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4487 SourceLocation DeclStart, 4488 Declarator &D, Expr *BitWidth, 4489 AccessSpecifier AS) { 4490 IdentifierInfo *II = D.getIdentifier(); 4491 SourceLocation Loc = DeclStart; 4492 if (II) Loc = D.getIdentifierLoc(); 4493 4494 DeclaratorInfo *DInfo = 0; 4495 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4496 if (getLangOptions().CPlusPlus) 4497 CheckExtraCXXDefaultArguments(D); 4498 4499 DiagnoseFunctionSpecifiers(D); 4500 4501 if (D.getDeclSpec().isThreadSpecified()) 4502 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4503 4504 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4505 4506 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4507 // Maybe we will complain about the shadowed template parameter. 4508 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4509 // Just pretend that we didn't see the previous declaration. 4510 PrevDecl = 0; 4511 } 4512 4513 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4514 PrevDecl = 0; 4515 4516 bool Mutable 4517 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4518 SourceLocation TSSL = D.getSourceRange().getBegin(); 4519 FieldDecl *NewFD 4520 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4521 AS, PrevDecl, &D); 4522 if (NewFD->isInvalidDecl() && PrevDecl) { 4523 // Don't introduce NewFD into scope; there's already something 4524 // with the same name in the same scope. 4525 } else if (II) { 4526 PushOnScopeChains(NewFD, S); 4527 } else 4528 Record->addDecl(NewFD); 4529 4530 return NewFD; 4531} 4532 4533/// \brief Build a new FieldDecl and check its well-formedness. 4534/// 4535/// This routine builds a new FieldDecl given the fields name, type, 4536/// record, etc. \p PrevDecl should refer to any previous declaration 4537/// with the same name and in the same scope as the field to be 4538/// created. 4539/// 4540/// \returns a new FieldDecl. 4541/// 4542/// \todo The Declarator argument is a hack. It will be removed once 4543FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4544 DeclaratorInfo *DInfo, 4545 RecordDecl *Record, SourceLocation Loc, 4546 bool Mutable, Expr *BitWidth, 4547 SourceLocation TSSL, 4548 AccessSpecifier AS, NamedDecl *PrevDecl, 4549 Declarator *D) { 4550 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4551 bool InvalidDecl = false; 4552 if (D) InvalidDecl = D->isInvalidType(); 4553 4554 // If we receive a broken type, recover by assuming 'int' and 4555 // marking this declaration as invalid. 4556 if (T.isNull()) { 4557 InvalidDecl = true; 4558 T = Context.IntTy; 4559 } 4560 4561 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4562 // than a variably modified type. 4563 if (T->isVariablyModifiedType()) { 4564 bool SizeIsNegative; 4565 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4566 SizeIsNegative); 4567 if (!FixedTy.isNull()) { 4568 Diag(Loc, diag::warn_illegal_constant_array_size); 4569 T = FixedTy; 4570 } else { 4571 if (SizeIsNegative) 4572 Diag(Loc, diag::err_typecheck_negative_array_size); 4573 else 4574 Diag(Loc, diag::err_typecheck_field_variable_size); 4575 InvalidDecl = true; 4576 } 4577 } 4578 4579 // Fields can not have abstract class types 4580 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4581 AbstractFieldType)) 4582 InvalidDecl = true; 4583 4584 bool ZeroWidth = false; 4585 // If this is declared as a bit-field, check the bit-field. 4586 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4587 InvalidDecl = true; 4588 DeleteExpr(BitWidth); 4589 BitWidth = 0; 4590 ZeroWidth = false; 4591 } 4592 4593 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4594 BitWidth, Mutable); 4595 if (InvalidDecl) 4596 NewFD->setInvalidDecl(); 4597 4598 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4599 Diag(Loc, diag::err_duplicate_member) << II; 4600 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4601 NewFD->setInvalidDecl(); 4602 } 4603 4604 if (getLangOptions().CPlusPlus) { 4605 QualType EltTy = Context.getBaseElementType(T); 4606 4607 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4608 4609 if (!T->isPODType()) 4610 CXXRecord->setPOD(false); 4611 if (!ZeroWidth) 4612 CXXRecord->setEmpty(false); 4613 4614 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4615 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4616 4617 if (!RDecl->hasTrivialConstructor()) 4618 CXXRecord->setHasTrivialConstructor(false); 4619 if (!RDecl->hasTrivialCopyConstructor()) 4620 CXXRecord->setHasTrivialCopyConstructor(false); 4621 if (!RDecl->hasTrivialCopyAssignment()) 4622 CXXRecord->setHasTrivialCopyAssignment(false); 4623 if (!RDecl->hasTrivialDestructor()) 4624 CXXRecord->setHasTrivialDestructor(false); 4625 4626 // C++ 9.5p1: An object of a class with a non-trivial 4627 // constructor, a non-trivial copy constructor, a non-trivial 4628 // destructor, or a non-trivial copy assignment operator 4629 // cannot be a member of a union, nor can an array of such 4630 // objects. 4631 // TODO: C++0x alters this restriction significantly. 4632 if (Record->isUnion()) { 4633 // We check for copy constructors before constructors 4634 // because otherwise we'll never get complaints about 4635 // copy constructors. 4636 4637 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4638 4639 CXXSpecialMember member; 4640 if (!RDecl->hasTrivialCopyConstructor()) 4641 member = CXXCopyConstructor; 4642 else if (!RDecl->hasTrivialConstructor()) 4643 member = CXXDefaultConstructor; 4644 else if (!RDecl->hasTrivialCopyAssignment()) 4645 member = CXXCopyAssignment; 4646 else if (!RDecl->hasTrivialDestructor()) 4647 member = CXXDestructor; 4648 else 4649 member = invalid; 4650 4651 if (member != invalid) { 4652 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4653 DiagnoseNontrivial(RT, member); 4654 NewFD->setInvalidDecl(); 4655 } 4656 } 4657 } 4658 } 4659 4660 // FIXME: We need to pass in the attributes given an AST 4661 // representation, not a parser representation. 4662 if (D) 4663 // FIXME: What to pass instead of TUScope? 4664 ProcessDeclAttributes(TUScope, NewFD, *D); 4665 4666 if (T.isObjCGCWeak()) 4667 Diag(Loc, diag::warn_attribute_weak_on_field); 4668 4669 NewFD->setAccess(AS); 4670 4671 // C++ [dcl.init.aggr]p1: 4672 // An aggregate is an array or a class (clause 9) with [...] no 4673 // private or protected non-static data members (clause 11). 4674 // A POD must be an aggregate. 4675 if (getLangOptions().CPlusPlus && 4676 (AS == AS_private || AS == AS_protected)) { 4677 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4678 CXXRecord->setAggregate(false); 4679 CXXRecord->setPOD(false); 4680 } 4681 4682 return NewFD; 4683} 4684 4685/// DiagnoseNontrivial - Given that a class has a non-trivial 4686/// special member, figure out why. 4687void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4688 QualType QT(T, 0U); 4689 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4690 4691 // Check whether the member was user-declared. 4692 switch (member) { 4693 case CXXDefaultConstructor: 4694 if (RD->hasUserDeclaredConstructor()) { 4695 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4696 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4697 if (!ci->isImplicitlyDefined(Context)) { 4698 SourceLocation CtorLoc = ci->getLocation(); 4699 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4700 return; 4701 } 4702 4703 assert(0 && "found no user-declared constructors"); 4704 return; 4705 } 4706 break; 4707 4708 case CXXCopyConstructor: 4709 if (RD->hasUserDeclaredCopyConstructor()) { 4710 SourceLocation CtorLoc = 4711 RD->getCopyConstructor(Context, 0)->getLocation(); 4712 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4713 return; 4714 } 4715 break; 4716 4717 case CXXCopyAssignment: 4718 if (RD->hasUserDeclaredCopyAssignment()) { 4719 // FIXME: this should use the location of the copy 4720 // assignment, not the type. 4721 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4722 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4723 return; 4724 } 4725 break; 4726 4727 case CXXDestructor: 4728 if (RD->hasUserDeclaredDestructor()) { 4729 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4730 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4731 return; 4732 } 4733 break; 4734 } 4735 4736 typedef CXXRecordDecl::base_class_iterator base_iter; 4737 4738 // Virtual bases and members inhibit trivial copying/construction, 4739 // but not trivial destruction. 4740 if (member != CXXDestructor) { 4741 // Check for virtual bases. vbases includes indirect virtual bases, 4742 // so we just iterate through the direct bases. 4743 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4744 if (bi->isVirtual()) { 4745 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4746 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4747 return; 4748 } 4749 4750 // Check for virtual methods. 4751 typedef CXXRecordDecl::method_iterator meth_iter; 4752 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4753 ++mi) { 4754 if (mi->isVirtual()) { 4755 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4756 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4757 return; 4758 } 4759 } 4760 } 4761 4762 bool (CXXRecordDecl::*hasTrivial)() const; 4763 switch (member) { 4764 case CXXDefaultConstructor: 4765 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4766 case CXXCopyConstructor: 4767 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4768 case CXXCopyAssignment: 4769 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4770 case CXXDestructor: 4771 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4772 default: 4773 assert(0 && "unexpected special member"); return; 4774 } 4775 4776 // Check for nontrivial bases (and recurse). 4777 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4778 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4779 assert(BaseRT); 4780 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4781 if (!(BaseRecTy->*hasTrivial)()) { 4782 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4783 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4784 DiagnoseNontrivial(BaseRT, member); 4785 return; 4786 } 4787 } 4788 4789 // Check for nontrivial members (and recurse). 4790 typedef RecordDecl::field_iterator field_iter; 4791 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4792 ++fi) { 4793 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4794 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4795 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4796 4797 if (!(EltRD->*hasTrivial)()) { 4798 SourceLocation FLoc = (*fi)->getLocation(); 4799 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4800 DiagnoseNontrivial(EltRT, member); 4801 return; 4802 } 4803 } 4804 } 4805 4806 assert(0 && "found no explanation for non-trivial member"); 4807} 4808 4809/// TranslateIvarVisibility - Translate visibility from a token ID to an 4810/// AST enum value. 4811static ObjCIvarDecl::AccessControl 4812TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4813 switch (ivarVisibility) { 4814 default: assert(0 && "Unknown visitibility kind"); 4815 case tok::objc_private: return ObjCIvarDecl::Private; 4816 case tok::objc_public: return ObjCIvarDecl::Public; 4817 case tok::objc_protected: return ObjCIvarDecl::Protected; 4818 case tok::objc_package: return ObjCIvarDecl::Package; 4819 } 4820} 4821 4822/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4823/// in order to create an IvarDecl object for it. 4824Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4825 SourceLocation DeclStart, 4826 DeclPtrTy IntfDecl, 4827 Declarator &D, ExprTy *BitfieldWidth, 4828 tok::ObjCKeywordKind Visibility) { 4829 4830 IdentifierInfo *II = D.getIdentifier(); 4831 Expr *BitWidth = (Expr*)BitfieldWidth; 4832 SourceLocation Loc = DeclStart; 4833 if (II) Loc = D.getIdentifierLoc(); 4834 4835 // FIXME: Unnamed fields can be handled in various different ways, for 4836 // example, unnamed unions inject all members into the struct namespace! 4837 4838 DeclaratorInfo *DInfo = 0; 4839 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4840 4841 if (BitWidth) { 4842 // 6.7.2.1p3, 6.7.2.1p4 4843 if (VerifyBitField(Loc, II, T, BitWidth)) { 4844 D.setInvalidType(); 4845 DeleteExpr(BitWidth); 4846 BitWidth = 0; 4847 } 4848 } else { 4849 // Not a bitfield. 4850 4851 // validate II. 4852 4853 } 4854 4855 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4856 // than a variably modified type. 4857 if (T->isVariablyModifiedType()) { 4858 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4859 D.setInvalidType(); 4860 } 4861 4862 // Get the visibility (access control) for this ivar. 4863 ObjCIvarDecl::AccessControl ac = 4864 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4865 : ObjCIvarDecl::None; 4866 // Must set ivar's DeclContext to its enclosing interface. 4867 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4868 DeclContext *EnclosingContext; 4869 if (ObjCImplementationDecl *IMPDecl = 4870 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4871 // Case of ivar declared in an implementation. Context is that of its class. 4872 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4873 assert(IDecl && "No class- ActOnIvar"); 4874 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4875 } else 4876 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4877 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4878 4879 // Construct the decl. 4880 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4881 EnclosingContext, Loc, II, T, 4882 DInfo, ac, (Expr *)BitfieldWidth); 4883 4884 if (II) { 4885 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4886 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4887 && !isa<TagDecl>(PrevDecl)) { 4888 Diag(Loc, diag::err_duplicate_member) << II; 4889 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4890 NewID->setInvalidDecl(); 4891 } 4892 } 4893 4894 // Process attributes attached to the ivar. 4895 ProcessDeclAttributes(S, NewID, D); 4896 4897 if (D.isInvalidType()) 4898 NewID->setInvalidDecl(); 4899 4900 if (II) { 4901 // FIXME: When interfaces are DeclContexts, we'll need to add 4902 // these to the interface. 4903 S->AddDecl(DeclPtrTy::make(NewID)); 4904 IdResolver.AddDecl(NewID); 4905 } 4906 4907 return DeclPtrTy::make(NewID); 4908} 4909 4910void Sema::ActOnFields(Scope* S, 4911 SourceLocation RecLoc, DeclPtrTy RecDecl, 4912 DeclPtrTy *Fields, unsigned NumFields, 4913 SourceLocation LBrac, SourceLocation RBrac, 4914 AttributeList *Attr) { 4915 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4916 assert(EnclosingDecl && "missing record or interface decl"); 4917 4918 // If the decl this is being inserted into is invalid, then it may be a 4919 // redeclaration or some other bogus case. Don't try to add fields to it. 4920 if (EnclosingDecl->isInvalidDecl()) { 4921 // FIXME: Deallocate fields? 4922 return; 4923 } 4924 4925 4926 // Verify that all the fields are okay. 4927 unsigned NumNamedMembers = 0; 4928 llvm::SmallVector<FieldDecl*, 32> RecFields; 4929 4930 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4931 for (unsigned i = 0; i != NumFields; ++i) { 4932 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4933 4934 // Get the type for the field. 4935 Type *FDTy = FD->getType().getTypePtr(); 4936 4937 if (!FD->isAnonymousStructOrUnion()) { 4938 // Remember all fields written by the user. 4939 RecFields.push_back(FD); 4940 } 4941 4942 // If the field is already invalid for some reason, don't emit more 4943 // diagnostics about it. 4944 if (FD->isInvalidDecl()) 4945 continue; 4946 4947 // C99 6.7.2.1p2: 4948 // A structure or union shall not contain a member with 4949 // incomplete or function type (hence, a structure shall not 4950 // contain an instance of itself, but may contain a pointer to 4951 // an instance of itself), except that the last member of a 4952 // structure with more than one named member may have incomplete 4953 // array type; such a structure (and any union containing, 4954 // possibly recursively, a member that is such a structure) 4955 // shall not be a member of a structure or an element of an 4956 // array. 4957 if (FDTy->isFunctionType()) { 4958 // Field declared as a function. 4959 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4960 << FD->getDeclName(); 4961 FD->setInvalidDecl(); 4962 EnclosingDecl->setInvalidDecl(); 4963 continue; 4964 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4965 Record && Record->isStruct()) { 4966 // Flexible array member. 4967 if (NumNamedMembers < 1) { 4968 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4969 << FD->getDeclName(); 4970 FD->setInvalidDecl(); 4971 EnclosingDecl->setInvalidDecl(); 4972 continue; 4973 } 4974 // Okay, we have a legal flexible array member at the end of the struct. 4975 if (Record) 4976 Record->setHasFlexibleArrayMember(true); 4977 } else if (!FDTy->isDependentType() && 4978 RequireCompleteType(FD->getLocation(), FD->getType(), 4979 diag::err_field_incomplete)) { 4980 // Incomplete type 4981 FD->setInvalidDecl(); 4982 EnclosingDecl->setInvalidDecl(); 4983 continue; 4984 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 4985 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4986 // If this is a member of a union, then entire union becomes "flexible". 4987 if (Record && Record->isUnion()) { 4988 Record->setHasFlexibleArrayMember(true); 4989 } else { 4990 // If this is a struct/class and this is not the last element, reject 4991 // it. Note that GCC supports variable sized arrays in the middle of 4992 // structures. 4993 if (i != NumFields-1) 4994 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4995 << FD->getDeclName() << FD->getType(); 4996 else { 4997 // We support flexible arrays at the end of structs in 4998 // other structs as an extension. 4999 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5000 << FD->getDeclName(); 5001 if (Record) 5002 Record->setHasFlexibleArrayMember(true); 5003 } 5004 } 5005 } 5006 if (Record && FDTTy->getDecl()->hasObjectMember()) 5007 Record->setHasObjectMember(true); 5008 } else if (FDTy->isObjCInterfaceType()) { 5009 /// A field cannot be an Objective-c object 5010 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5011 FD->setInvalidDecl(); 5012 EnclosingDecl->setInvalidDecl(); 5013 continue; 5014 } else if (getLangOptions().ObjC1 && 5015 getLangOptions().getGCMode() != LangOptions::NonGC && 5016 Record && 5017 (FD->getType()->isObjCObjectPointerType() || 5018 FD->getType().isObjCGCStrong())) 5019 Record->setHasObjectMember(true); 5020 // Keep track of the number of named members. 5021 if (FD->getIdentifier()) 5022 ++NumNamedMembers; 5023 } 5024 5025 // Okay, we successfully defined 'Record'. 5026 if (Record) { 5027 Record->completeDefinition(Context); 5028 } else { 5029 ObjCIvarDecl **ClsFields = 5030 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5031 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5032 ID->setIVarList(ClsFields, RecFields.size(), Context); 5033 ID->setLocEnd(RBrac); 5034 // Add ivar's to class's DeclContext. 5035 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5036 ClsFields[i]->setLexicalDeclContext(ID); 5037 ID->addDecl(ClsFields[i]); 5038 } 5039 // Must enforce the rule that ivars in the base classes may not be 5040 // duplicates. 5041 if (ID->getSuperClass()) { 5042 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5043 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5044 ObjCIvarDecl* Ivar = (*IVI); 5045 5046 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5047 ObjCIvarDecl* prevIvar = 5048 ID->getSuperClass()->lookupInstanceVariable(II); 5049 if (prevIvar) { 5050 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5051 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5052 } 5053 } 5054 } 5055 } 5056 } else if (ObjCImplementationDecl *IMPDecl = 5057 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5058 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5059 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5060 // Ivar declared in @implementation never belongs to the implementation. 5061 // Only it is in implementation's lexical context. 5062 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5063 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5064 } 5065 } 5066 5067 if (Attr) 5068 ProcessDeclAttributeList(S, Record, Attr); 5069} 5070 5071EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5072 EnumConstantDecl *LastEnumConst, 5073 SourceLocation IdLoc, 5074 IdentifierInfo *Id, 5075 ExprArg val) { 5076 Expr *Val = (Expr *)val.get(); 5077 5078 llvm::APSInt EnumVal(32); 5079 QualType EltTy; 5080 if (Val && !Val->isTypeDependent()) { 5081 // Make sure to promote the operand type to int. 5082 UsualUnaryConversions(Val); 5083 if (Val != val.get()) { 5084 val.release(); 5085 val = Val; 5086 } 5087 5088 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5089 SourceLocation ExpLoc; 5090 if (!Val->isValueDependent() && 5091 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5092 Val = 0; 5093 } else { 5094 EltTy = Val->getType(); 5095 } 5096 } 5097 5098 if (!Val) { 5099 if (LastEnumConst) { 5100 // Assign the last value + 1. 5101 EnumVal = LastEnumConst->getInitVal(); 5102 ++EnumVal; 5103 5104 // Check for overflow on increment. 5105 if (EnumVal < LastEnumConst->getInitVal()) 5106 Diag(IdLoc, diag::warn_enum_value_overflow); 5107 5108 EltTy = LastEnumConst->getType(); 5109 } else { 5110 // First value, set to zero. 5111 EltTy = Context.IntTy; 5112 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5113 } 5114 } 5115 5116 val.release(); 5117 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5118 Val, EnumVal); 5119} 5120 5121 5122Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5123 DeclPtrTy lastEnumConst, 5124 SourceLocation IdLoc, 5125 IdentifierInfo *Id, 5126 SourceLocation EqualLoc, ExprTy *val) { 5127 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5128 EnumConstantDecl *LastEnumConst = 5129 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5130 Expr *Val = static_cast<Expr*>(val); 5131 5132 // The scope passed in may not be a decl scope. Zip up the scope tree until 5133 // we find one that is. 5134 S = getNonFieldDeclScope(S); 5135 5136 // Verify that there isn't already something declared with this name in this 5137 // scope. 5138 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5139 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5140 // Maybe we will complain about the shadowed template parameter. 5141 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5142 // Just pretend that we didn't see the previous declaration. 5143 PrevDecl = 0; 5144 } 5145 5146 if (PrevDecl) { 5147 // When in C++, we may get a TagDecl with the same name; in this case the 5148 // enum constant will 'hide' the tag. 5149 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5150 "Received TagDecl when not in C++!"); 5151 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5152 if (isa<EnumConstantDecl>(PrevDecl)) 5153 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5154 else 5155 Diag(IdLoc, diag::err_redefinition) << Id; 5156 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5157 if (Val) Val->Destroy(Context); 5158 return DeclPtrTy(); 5159 } 5160 } 5161 5162 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5163 IdLoc, Id, Owned(Val)); 5164 5165 // Register this decl in the current scope stack. 5166 if (New) 5167 PushOnScopeChains(New, S); 5168 5169 return DeclPtrTy::make(New); 5170} 5171 5172void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5173 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5174 DeclPtrTy *Elements, unsigned NumElements, 5175 Scope *S, AttributeList *Attr) { 5176 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5177 QualType EnumType = Context.getTypeDeclType(Enum); 5178 5179 if (Attr) 5180 ProcessDeclAttributeList(S, Enum, Attr); 5181 5182 // TODO: If the result value doesn't fit in an int, it must be a long or long 5183 // long value. ISO C does not support this, but GCC does as an extension, 5184 // emit a warning. 5185 unsigned IntWidth = Context.Target.getIntWidth(); 5186 unsigned CharWidth = Context.Target.getCharWidth(); 5187 unsigned ShortWidth = Context.Target.getShortWidth(); 5188 5189 // Verify that all the values are okay, compute the size of the values, and 5190 // reverse the list. 5191 unsigned NumNegativeBits = 0; 5192 unsigned NumPositiveBits = 0; 5193 5194 // Keep track of whether all elements have type int. 5195 bool AllElementsInt = true; 5196 5197 for (unsigned i = 0; i != NumElements; ++i) { 5198 EnumConstantDecl *ECD = 5199 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5200 if (!ECD) continue; // Already issued a diagnostic. 5201 5202 // If the enum value doesn't fit in an int, emit an extension warning. 5203 const llvm::APSInt &InitVal = ECD->getInitVal(); 5204 assert(InitVal.getBitWidth() >= IntWidth && 5205 "Should have promoted value to int"); 5206 if (InitVal.getBitWidth() > IntWidth) { 5207 llvm::APSInt V(InitVal); 5208 V.trunc(IntWidth); 5209 V.extend(InitVal.getBitWidth()); 5210 if (V != InitVal) 5211 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5212 << InitVal.toString(10); 5213 } 5214 5215 // Keep track of the size of positive and negative values. 5216 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5217 NumPositiveBits = std::max(NumPositiveBits, 5218 (unsigned)InitVal.getActiveBits()); 5219 else 5220 NumNegativeBits = std::max(NumNegativeBits, 5221 (unsigned)InitVal.getMinSignedBits()); 5222 5223 // Keep track of whether every enum element has type int (very commmon). 5224 if (AllElementsInt) 5225 AllElementsInt = ECD->getType() == Context.IntTy; 5226 } 5227 5228 // Figure out the type that should be used for this enum. 5229 // FIXME: Support -fshort-enums. 5230 QualType BestType; 5231 unsigned BestWidth; 5232 5233 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5234 5235 if (NumNegativeBits) { 5236 // If there is a negative value, figure out the smallest integer type (of 5237 // int/long/longlong) that fits. 5238 // If it's packed, check also if it fits a char or a short. 5239 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5240 BestType = Context.SignedCharTy; 5241 BestWidth = CharWidth; 5242 } else if (Packed && NumNegativeBits <= ShortWidth && 5243 NumPositiveBits < ShortWidth) { 5244 BestType = Context.ShortTy; 5245 BestWidth = ShortWidth; 5246 } 5247 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5248 BestType = Context.IntTy; 5249 BestWidth = IntWidth; 5250 } else { 5251 BestWidth = Context.Target.getLongWidth(); 5252 5253 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5254 BestType = Context.LongTy; 5255 else { 5256 BestWidth = Context.Target.getLongLongWidth(); 5257 5258 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5259 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5260 BestType = Context.LongLongTy; 5261 } 5262 } 5263 } else { 5264 // If there is no negative value, figure out which of uint, ulong, ulonglong 5265 // fits. 5266 // If it's packed, check also if it fits a char or a short. 5267 if (Packed && NumPositiveBits <= CharWidth) { 5268 BestType = Context.UnsignedCharTy; 5269 BestWidth = CharWidth; 5270 } else if (Packed && NumPositiveBits <= ShortWidth) { 5271 BestType = Context.UnsignedShortTy; 5272 BestWidth = ShortWidth; 5273 } 5274 else if (NumPositiveBits <= IntWidth) { 5275 BestType = Context.UnsignedIntTy; 5276 BestWidth = IntWidth; 5277 } else if (NumPositiveBits <= 5278 (BestWidth = Context.Target.getLongWidth())) { 5279 BestType = Context.UnsignedLongTy; 5280 } else { 5281 BestWidth = Context.Target.getLongLongWidth(); 5282 assert(NumPositiveBits <= BestWidth && 5283 "How could an initializer get larger than ULL?"); 5284 BestType = Context.UnsignedLongLongTy; 5285 } 5286 } 5287 5288 // Loop over all of the enumerator constants, changing their types to match 5289 // the type of the enum if needed. 5290 for (unsigned i = 0; i != NumElements; ++i) { 5291 EnumConstantDecl *ECD = 5292 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5293 if (!ECD) continue; // Already issued a diagnostic. 5294 5295 // Standard C says the enumerators have int type, but we allow, as an 5296 // extension, the enumerators to be larger than int size. If each 5297 // enumerator value fits in an int, type it as an int, otherwise type it the 5298 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5299 // that X has type 'int', not 'unsigned'. 5300 if (ECD->getType() == Context.IntTy) { 5301 // Make sure the init value is signed. 5302 llvm::APSInt IV = ECD->getInitVal(); 5303 IV.setIsSigned(true); 5304 ECD->setInitVal(IV); 5305 5306 if (getLangOptions().CPlusPlus) 5307 // C++ [dcl.enum]p4: Following the closing brace of an 5308 // enum-specifier, each enumerator has the type of its 5309 // enumeration. 5310 ECD->setType(EnumType); 5311 continue; // Already int type. 5312 } 5313 5314 // Determine whether the value fits into an int. 5315 llvm::APSInt InitVal = ECD->getInitVal(); 5316 bool FitsInInt; 5317 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5318 FitsInInt = InitVal.getActiveBits() < IntWidth; 5319 else 5320 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5321 5322 // If it fits into an integer type, force it. Otherwise force it to match 5323 // the enum decl type. 5324 QualType NewTy; 5325 unsigned NewWidth; 5326 bool NewSign; 5327 if (FitsInInt) { 5328 NewTy = Context.IntTy; 5329 NewWidth = IntWidth; 5330 NewSign = true; 5331 } else if (ECD->getType() == BestType) { 5332 // Already the right type! 5333 if (getLangOptions().CPlusPlus) 5334 // C++ [dcl.enum]p4: Following the closing brace of an 5335 // enum-specifier, each enumerator has the type of its 5336 // enumeration. 5337 ECD->setType(EnumType); 5338 continue; 5339 } else { 5340 NewTy = BestType; 5341 NewWidth = BestWidth; 5342 NewSign = BestType->isSignedIntegerType(); 5343 } 5344 5345 // Adjust the APSInt value. 5346 InitVal.extOrTrunc(NewWidth); 5347 InitVal.setIsSigned(NewSign); 5348 ECD->setInitVal(InitVal); 5349 5350 // Adjust the Expr initializer and type. 5351 if (ECD->getInitExpr()) 5352 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5353 CastExpr::CK_Unknown, 5354 ECD->getInitExpr(), 5355 /*isLvalue=*/false)); 5356 if (getLangOptions().CPlusPlus) 5357 // C++ [dcl.enum]p4: Following the closing brace of an 5358 // enum-specifier, each enumerator has the type of its 5359 // enumeration. 5360 ECD->setType(EnumType); 5361 else 5362 ECD->setType(NewTy); 5363 } 5364 5365 Enum->completeDefinition(Context, BestType); 5366} 5367 5368Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5369 ExprArg expr) { 5370 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5371 5372 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5373 Loc, AsmString); 5374 CurContext->addDecl(New); 5375 return DeclPtrTy::make(New); 5376} 5377 5378void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5379 SourceLocation PragmaLoc, 5380 SourceLocation NameLoc) { 5381 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5382 5383 if (PrevDecl) { 5384 PrevDecl->addAttr(::new (Context) WeakAttr()); 5385 } else { 5386 (void)WeakUndeclaredIdentifiers.insert( 5387 std::pair<IdentifierInfo*,WeakInfo> 5388 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5389 } 5390} 5391 5392void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5393 IdentifierInfo* AliasName, 5394 SourceLocation PragmaLoc, 5395 SourceLocation NameLoc, 5396 SourceLocation AliasNameLoc) { 5397 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5398 WeakInfo W = WeakInfo(Name, NameLoc); 5399 5400 if (PrevDecl) { 5401 if (!PrevDecl->hasAttr<AliasAttr>()) 5402 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5403 DeclApplyPragmaWeak(TUScope, ND, W); 5404 } else { 5405 (void)WeakUndeclaredIdentifiers.insert( 5406 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5407 } 5408} 5409