SemaDecl.cpp revision f4d84b663ef7dda959cbe45561d90e59760cbb74
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) { 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 CurContext->addDecl(D); 297 298 // C++ [basic.scope]p4: 299 // -- exactly one declaration shall declare a class name or 300 // enumeration name that is not a typedef name and the other 301 // declarations shall all refer to the same object or 302 // enumerator, or all refer to functions and function templates; 303 // in this case the class name or enumeration name is hidden. 304 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 305 // We are pushing the name of a tag (enum or class). 306 if (CurContext->getLookupContext() 307 == TD->getDeclContext()->getLookupContext()) { 308 // We're pushing the tag into the current context, which might 309 // require some reshuffling in the identifier resolver. 310 IdentifierResolver::iterator 311 I = IdResolver.begin(TD->getDeclName()), 312 IEnd = IdResolver.end(); 313 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 314 NamedDecl *PrevDecl = *I; 315 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 316 PrevDecl = *I, ++I) { 317 if (TD->declarationReplaces(*I)) { 318 // This is a redeclaration. Remove it from the chain and 319 // break out, so that we'll add in the shadowed 320 // declaration. 321 S->RemoveDecl(DeclPtrTy::make(*I)); 322 if (PrevDecl == *I) { 323 IdResolver.RemoveDecl(*I); 324 IdResolver.AddDecl(TD); 325 return; 326 } else { 327 IdResolver.RemoveDecl(*I); 328 break; 329 } 330 } 331 } 332 333 // There is already a declaration with the same name in the same 334 // scope, which is not a tag declaration. It must be found 335 // before we find the new declaration, so insert the new 336 // declaration at the end of the chain. 337 IdResolver.AddShadowedDecl(TD, PrevDecl); 338 339 return; 340 } 341 } 342 } else if ((isa<FunctionDecl>(D) && 343 AllowOverloadingOfFunction(D, Context)) || 344 isa<FunctionTemplateDecl>(D)) { 345 // We are pushing the name of a function or function template, 346 // which might be an overloaded name. 347 IdentifierResolver::iterator Redecl 348 = std::find_if(IdResolver.begin(D->getDeclName()), 349 IdResolver.end(), 350 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 351 D)); 352 if (Redecl != IdResolver.end() && 353 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 354 // There is already a declaration of a function on our 355 // IdResolver chain. Replace it with this declaration. 356 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 357 IdResolver.RemoveDecl(*Redecl); 358 } 359 } else if (isa<ObjCInterfaceDecl>(D)) { 360 // We're pushing an Objective-C interface into the current 361 // context. If there is already an alias declaration, remove it first. 362 for (IdentifierResolver::iterator 363 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 364 I != IEnd; ++I) { 365 if (isa<ObjCCompatibleAliasDecl>(*I)) { 366 S->RemoveDecl(DeclPtrTy::make(*I)); 367 IdResolver.RemoveDecl(*I); 368 break; 369 } 370 } 371 } 372 373 IdResolver.AddDecl(D); 374} 375 376void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 377 if (S->decl_empty()) return; 378 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 379 "Scope shouldn't contain decls!"); 380 381 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 382 I != E; ++I) { 383 Decl *TmpD = (*I).getAs<Decl>(); 384 assert(TmpD && "This decl didn't get pushed??"); 385 386 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 387 NamedDecl *D = cast<NamedDecl>(TmpD); 388 389 if (!D->getDeclName()) continue; 390 391 // Remove this name from our lexical scope. 392 IdResolver.RemoveDecl(D); 393 } 394} 395 396/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 397/// return 0 if one not found. 398ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 399 // The third "scope" argument is 0 since we aren't enabling lazy built-in 400 // creation from this context. 401 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 402 403 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 404} 405 406/// getNonFieldDeclScope - Retrieves the innermost scope, starting 407/// from S, where a non-field would be declared. This routine copes 408/// with the difference between C and C++ scoping rules in structs and 409/// unions. For example, the following code is well-formed in C but 410/// ill-formed in C++: 411/// @code 412/// struct S6 { 413/// enum { BAR } e; 414/// }; 415/// 416/// void test_S6() { 417/// struct S6 a; 418/// a.e = BAR; 419/// } 420/// @endcode 421/// For the declaration of BAR, this routine will return a different 422/// scope. The scope S will be the scope of the unnamed enumeration 423/// within S6. In C++, this routine will return the scope associated 424/// with S6, because the enumeration's scope is a transparent 425/// context but structures can contain non-field names. In C, this 426/// routine will return the translation unit scope, since the 427/// enumeration's scope is a transparent context and structures cannot 428/// contain non-field names. 429Scope *Sema::getNonFieldDeclScope(Scope *S) { 430 while (((S->getFlags() & Scope::DeclScope) == 0) || 431 (S->getEntity() && 432 ((DeclContext *)S->getEntity())->isTransparentContext()) || 433 (S->isClassScope() && !getLangOptions().CPlusPlus)) 434 S = S->getParent(); 435 return S; 436} 437 438void Sema::InitBuiltinVaListType() { 439 if (!Context.getBuiltinVaListType().isNull()) 440 return; 441 442 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 443 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 444 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 445 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 446} 447 448/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 449/// file scope. lazily create a decl for it. ForRedeclaration is true 450/// if we're creating this built-in in anticipation of redeclaring the 451/// built-in. 452NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 453 Scope *S, bool ForRedeclaration, 454 SourceLocation Loc) { 455 Builtin::ID BID = (Builtin::ID)bid; 456 457 if (Context.BuiltinInfo.hasVAListUse(BID)) 458 InitBuiltinVaListType(); 459 460 ASTContext::GetBuiltinTypeError Error; 461 QualType R = Context.GetBuiltinType(BID, Error); 462 switch (Error) { 463 case ASTContext::GE_None: 464 // Okay 465 break; 466 467 case ASTContext::GE_Missing_stdio: 468 if (ForRedeclaration) 469 Diag(Loc, diag::err_implicit_decl_requires_stdio) 470 << Context.BuiltinInfo.GetName(BID); 471 return 0; 472 473 case ASTContext::GE_Missing_setjmp: 474 if (ForRedeclaration) 475 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 476 << Context.BuiltinInfo.GetName(BID); 477 return 0; 478 } 479 480 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 481 Diag(Loc, diag::ext_implicit_lib_function_decl) 482 << Context.BuiltinInfo.GetName(BID) 483 << R; 484 if (Context.BuiltinInfo.getHeaderName(BID) && 485 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 486 != Diagnostic::Ignored) 487 Diag(Loc, diag::note_please_include_header) 488 << Context.BuiltinInfo.getHeaderName(BID) 489 << Context.BuiltinInfo.GetName(BID); 490 } 491 492 FunctionDecl *New = FunctionDecl::Create(Context, 493 Context.getTranslationUnitDecl(), 494 Loc, II, R, /*DInfo=*/0, 495 FunctionDecl::Extern, false, 496 /*hasPrototype=*/true); 497 New->setImplicit(); 498 499 // Create Decl objects for each parameter, adding them to the 500 // FunctionDecl. 501 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 502 llvm::SmallVector<ParmVarDecl*, 16> Params; 503 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 504 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 505 FT->getArgType(i), /*DInfo=*/0, 506 VarDecl::None, 0)); 507 New->setParams(Context, Params.data(), Params.size()); 508 } 509 510 AddKnownFunctionAttributes(New); 511 512 // TUScope is the translation-unit scope to insert this function into. 513 // FIXME: This is hideous. We need to teach PushOnScopeChains to 514 // relate Scopes to DeclContexts, and probably eliminate CurContext 515 // entirely, but we're not there yet. 516 DeclContext *SavedContext = CurContext; 517 CurContext = Context.getTranslationUnitDecl(); 518 PushOnScopeChains(New, TUScope); 519 CurContext = SavedContext; 520 return New; 521} 522 523/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 524/// everything from the standard library is defined. 525NamespaceDecl *Sema::GetStdNamespace() { 526 if (!StdNamespace) { 527 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 528 DeclContext *Global = Context.getTranslationUnitDecl(); 529 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 530 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 531 } 532 return StdNamespace; 533} 534 535/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 536/// same name and scope as a previous declaration 'Old'. Figure out 537/// how to resolve this situation, merging decls or emitting 538/// diagnostics as appropriate. If there was an error, set New to be invalid. 539/// 540void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 541 // If either decl is known invalid already, set the new one to be invalid and 542 // don't bother doing any merging checks. 543 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 544 return New->setInvalidDecl(); 545 546 // Allow multiple definitions for ObjC built-in typedefs. 547 // FIXME: Verify the underlying types are equivalent! 548 if (getLangOptions().ObjC1) { 549 const IdentifierInfo *TypeID = New->getIdentifier(); 550 switch (TypeID->getLength()) { 551 default: break; 552 case 2: 553 if (!TypeID->isStr("id")) 554 break; 555 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 556 // Install the built-in type for 'id', ignoring the current definition. 557 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 558 return; 559 case 5: 560 if (!TypeID->isStr("Class")) 561 break; 562 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 563 // Install the built-in type for 'Class', ignoring the current definition. 564 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 565 return; 566 case 3: 567 if (!TypeID->isStr("SEL")) 568 break; 569 Context.setObjCSelType(Context.getTypeDeclType(New)); 570 return; 571 case 8: 572 if (!TypeID->isStr("Protocol")) 573 break; 574 Context.setObjCProtoType(New->getUnderlyingType()); 575 return; 576 } 577 // Fall through - the typedef name was not a builtin type. 578 } 579 // Verify the old decl was also a type. 580 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 581 if (!Old) { 582 Diag(New->getLocation(), diag::err_redefinition_different_kind) 583 << New->getDeclName(); 584 if (OldD->getLocation().isValid()) 585 Diag(OldD->getLocation(), diag::note_previous_definition); 586 return New->setInvalidDecl(); 587 } 588 589 // Determine the "old" type we'll use for checking and diagnostics. 590 QualType OldType; 591 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 592 OldType = OldTypedef->getUnderlyingType(); 593 else 594 OldType = Context.getTypeDeclType(Old); 595 596 // If the typedef types are not identical, reject them in all languages and 597 // with any extensions enabled. 598 599 if (OldType != New->getUnderlyingType() && 600 Context.getCanonicalType(OldType) != 601 Context.getCanonicalType(New->getUnderlyingType())) { 602 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 603 << New->getUnderlyingType() << OldType; 604 if (Old->getLocation().isValid()) 605 Diag(Old->getLocation(), diag::note_previous_definition); 606 return New->setInvalidDecl(); 607 } 608 609 if (getLangOptions().Microsoft) 610 return; 611 612 // C++ [dcl.typedef]p2: 613 // In a given non-class scope, a typedef specifier can be used to 614 // redefine the name of any type declared in that scope to refer 615 // to the type to which it already refers. 616 if (getLangOptions().CPlusPlus) { 617 if (!isa<CXXRecordDecl>(CurContext)) 618 return; 619 Diag(New->getLocation(), diag::err_redefinition) 620 << New->getDeclName(); 621 Diag(Old->getLocation(), diag::note_previous_definition); 622 return New->setInvalidDecl(); 623 } 624 625 // If we have a redefinition of a typedef in C, emit a warning. This warning 626 // is normally mapped to an error, but can be controlled with 627 // -Wtypedef-redefinition. If either the original or the redefinition is 628 // in a system header, don't emit this for compatibility with GCC. 629 if (PP.getDiagnostics().getSuppressSystemWarnings() && 630 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 631 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 632 return; 633 634 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 635 << New->getDeclName(); 636 Diag(Old->getLocation(), diag::note_previous_definition); 637 return; 638} 639 640/// DeclhasAttr - returns true if decl Declaration already has the target 641/// attribute. 642static bool 643DeclHasAttr(const Decl *decl, const Attr *target) { 644 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 645 if (attr->getKind() == target->getKind()) 646 return true; 647 648 return false; 649} 650 651/// MergeAttributes - append attributes from the Old decl to the New one. 652static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 653 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 654 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 655 Attr *NewAttr = attr->clone(C); 656 NewAttr->setInherited(true); 657 New->addAttr(NewAttr); 658 } 659 } 660} 661 662/// Used in MergeFunctionDecl to keep track of function parameters in 663/// C. 664struct GNUCompatibleParamWarning { 665 ParmVarDecl *OldParm; 666 ParmVarDecl *NewParm; 667 QualType PromotedType; 668}; 669 670/// MergeFunctionDecl - We just parsed a function 'New' from 671/// declarator D which has the same name and scope as a previous 672/// declaration 'Old'. Figure out how to resolve this situation, 673/// merging decls or emitting diagnostics as appropriate. 674/// 675/// In C++, New and Old must be declarations that are not 676/// overloaded. Use IsOverload to determine whether New and Old are 677/// overloaded, and to select the Old declaration that New should be 678/// merged with. 679/// 680/// Returns true if there was an error, false otherwise. 681bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 682 assert(!isa<OverloadedFunctionDecl>(OldD) && 683 "Cannot merge with an overloaded function declaration"); 684 685 // Verify the old decl was also a function. 686 FunctionDecl *Old = 0; 687 if (FunctionTemplateDecl *OldFunctionTemplate 688 = dyn_cast<FunctionTemplateDecl>(OldD)) 689 Old = OldFunctionTemplate->getTemplatedDecl(); 690 else 691 Old = dyn_cast<FunctionDecl>(OldD); 692 if (!Old) { 693 Diag(New->getLocation(), diag::err_redefinition_different_kind) 694 << New->getDeclName(); 695 Diag(OldD->getLocation(), diag::note_previous_definition); 696 return true; 697 } 698 699 // Determine whether the previous declaration was a definition, 700 // implicit declaration, or a declaration. 701 diag::kind PrevDiag; 702 if (Old->isThisDeclarationADefinition()) 703 PrevDiag = diag::note_previous_definition; 704 else if (Old->isImplicit()) 705 PrevDiag = diag::note_previous_implicit_declaration; 706 else 707 PrevDiag = diag::note_previous_declaration; 708 709 QualType OldQType = Context.getCanonicalType(Old->getType()); 710 QualType NewQType = Context.getCanonicalType(New->getType()); 711 712 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 713 New->getStorageClass() == FunctionDecl::Static && 714 Old->getStorageClass() != FunctionDecl::Static) { 715 Diag(New->getLocation(), diag::err_static_non_static) 716 << New; 717 Diag(Old->getLocation(), PrevDiag); 718 return true; 719 } 720 721 if (getLangOptions().CPlusPlus) { 722 // (C++98 13.1p2): 723 // Certain function declarations cannot be overloaded: 724 // -- Function declarations that differ only in the return type 725 // cannot be overloaded. 726 QualType OldReturnType 727 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 728 QualType NewReturnType 729 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 730 if (OldReturnType != NewReturnType) { 731 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 732 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 733 return true; 734 } 735 736 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 737 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 738 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 739 NewMethod->getLexicalDeclContext()->isRecord()) { 740 // -- Member function declarations with the same name and the 741 // same parameter types cannot be overloaded if any of them 742 // is a static member function declaration. 743 if (OldMethod->isStatic() || NewMethod->isStatic()) { 744 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 745 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 746 return true; 747 } 748 749 // C++ [class.mem]p1: 750 // [...] A member shall not be declared twice in the 751 // member-specification, except that a nested class or member 752 // class template can be declared and then later defined. 753 unsigned NewDiag; 754 if (isa<CXXConstructorDecl>(OldMethod)) 755 NewDiag = diag::err_constructor_redeclared; 756 else if (isa<CXXDestructorDecl>(NewMethod)) 757 NewDiag = diag::err_destructor_redeclared; 758 else if (isa<CXXConversionDecl>(NewMethod)) 759 NewDiag = diag::err_conv_function_redeclared; 760 else 761 NewDiag = diag::err_member_redeclared; 762 763 Diag(New->getLocation(), NewDiag); 764 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 765 } 766 767 // (C++98 8.3.5p3): 768 // All declarations for a function shall agree exactly in both the 769 // return type and the parameter-type-list. 770 if (OldQType == NewQType) 771 return MergeCompatibleFunctionDecls(New, Old); 772 773 // Fall through for conflicting redeclarations and redefinitions. 774 } 775 776 // C: Function types need to be compatible, not identical. This handles 777 // duplicate function decls like "void f(int); void f(enum X);" properly. 778 if (!getLangOptions().CPlusPlus && 779 Context.typesAreCompatible(OldQType, NewQType)) { 780 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 781 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 782 const FunctionProtoType *OldProto = 0; 783 if (isa<FunctionNoProtoType>(NewFuncType) && 784 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 785 // The old declaration provided a function prototype, but the 786 // new declaration does not. Merge in the prototype. 787 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 788 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 789 OldProto->arg_type_end()); 790 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 791 ParamTypes.data(), ParamTypes.size(), 792 OldProto->isVariadic(), 793 OldProto->getTypeQuals()); 794 New->setType(NewQType); 795 New->setHasInheritedPrototype(); 796 797 // Synthesize a parameter for each argument type. 798 llvm::SmallVector<ParmVarDecl*, 16> Params; 799 for (FunctionProtoType::arg_type_iterator 800 ParamType = OldProto->arg_type_begin(), 801 ParamEnd = OldProto->arg_type_end(); 802 ParamType != ParamEnd; ++ParamType) { 803 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 804 SourceLocation(), 0, 805 *ParamType, /*DInfo=*/0, 806 VarDecl::None, 0); 807 Param->setImplicit(); 808 Params.push_back(Param); 809 } 810 811 New->setParams(Context, Params.data(), Params.size()); 812 } 813 814 return MergeCompatibleFunctionDecls(New, Old); 815 } 816 817 // GNU C permits a K&R definition to follow a prototype declaration 818 // if the declared types of the parameters in the K&R definition 819 // match the types in the prototype declaration, even when the 820 // promoted types of the parameters from the K&R definition differ 821 // from the types in the prototype. GCC then keeps the types from 822 // the prototype. 823 // 824 // If a variadic prototype is followed by a non-variadic K&R definition, 825 // the K&R definition becomes variadic. This is sort of an edge case, but 826 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 827 // C99 6.9.1p8. 828 if (!getLangOptions().CPlusPlus && 829 Old->hasPrototype() && !New->hasPrototype() && 830 New->getType()->getAsFunctionProtoType() && 831 Old->getNumParams() == New->getNumParams()) { 832 llvm::SmallVector<QualType, 16> ArgTypes; 833 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 834 const FunctionProtoType *OldProto 835 = Old->getType()->getAsFunctionProtoType(); 836 const FunctionProtoType *NewProto 837 = New->getType()->getAsFunctionProtoType(); 838 839 // Determine whether this is the GNU C extension. 840 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 841 NewProto->getResultType()); 842 bool LooseCompatible = !MergedReturn.isNull(); 843 for (unsigned Idx = 0, End = Old->getNumParams(); 844 LooseCompatible && Idx != End; ++Idx) { 845 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 846 ParmVarDecl *NewParm = New->getParamDecl(Idx); 847 if (Context.typesAreCompatible(OldParm->getType(), 848 NewProto->getArgType(Idx))) { 849 ArgTypes.push_back(NewParm->getType()); 850 } else if (Context.typesAreCompatible(OldParm->getType(), 851 NewParm->getType())) { 852 GNUCompatibleParamWarning Warn 853 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 854 Warnings.push_back(Warn); 855 ArgTypes.push_back(NewParm->getType()); 856 } else 857 LooseCompatible = false; 858 } 859 860 if (LooseCompatible) { 861 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 862 Diag(Warnings[Warn].NewParm->getLocation(), 863 diag::ext_param_promoted_not_compatible_with_prototype) 864 << Warnings[Warn].PromotedType 865 << Warnings[Warn].OldParm->getType(); 866 Diag(Warnings[Warn].OldParm->getLocation(), 867 diag::note_previous_declaration); 868 } 869 870 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 871 ArgTypes.size(), 872 OldProto->isVariadic(), 0)); 873 return MergeCompatibleFunctionDecls(New, Old); 874 } 875 876 // Fall through to diagnose conflicting types. 877 } 878 879 // A function that has already been declared has been redeclared or defined 880 // with a different type- show appropriate diagnostic 881 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 882 // The user has declared a builtin function with an incompatible 883 // signature. 884 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 885 // The function the user is redeclaring is a library-defined 886 // function like 'malloc' or 'printf'. Warn about the 887 // redeclaration, then pretend that we don't know about this 888 // library built-in. 889 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 890 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 891 << Old << Old->getType(); 892 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 893 Old->setInvalidDecl(); 894 return false; 895 } 896 897 PrevDiag = diag::note_previous_builtin_declaration; 898 } 899 900 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 901 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 902 return true; 903} 904 905/// \brief Completes the merge of two function declarations that are 906/// known to be compatible. 907/// 908/// This routine handles the merging of attributes and other 909/// properties of function declarations form the old declaration to 910/// the new declaration, once we know that New is in fact a 911/// redeclaration of Old. 912/// 913/// \returns false 914bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 915 // Merge the attributes 916 MergeAttributes(New, Old, Context); 917 918 // Merge the storage class. 919 if (Old->getStorageClass() != FunctionDecl::Extern) 920 New->setStorageClass(Old->getStorageClass()); 921 922 // Merge "inline" 923 if (Old->isInline()) 924 New->setInline(true); 925 926 // If this function declaration by itself qualifies as a C99 inline 927 // definition (C99 6.7.4p6), but the previous definition did not, 928 // then the function is not a C99 inline definition. 929 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 930 New->setC99InlineDefinition(false); 931 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 932 // Mark all preceding definitions as not being C99 inline definitions. 933 for (const FunctionDecl *Prev = Old; Prev; 934 Prev = Prev->getPreviousDeclaration()) 935 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 936 } 937 938 // Merge "pure" flag. 939 if (Old->isPure()) 940 New->setPure(); 941 942 // Merge the "deleted" flag. 943 if (Old->isDeleted()) 944 New->setDeleted(); 945 946 if (getLangOptions().CPlusPlus) 947 return MergeCXXFunctionDecl(New, Old); 948 949 return false; 950} 951 952/// MergeVarDecl - We just parsed a variable 'New' which has the same name 953/// and scope as a previous declaration 'Old'. Figure out how to resolve this 954/// situation, merging decls or emitting diagnostics as appropriate. 955/// 956/// Tentative definition rules (C99 6.9.2p2) are checked by 957/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 958/// definitions here, since the initializer hasn't been attached. 959/// 960void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 961 // If either decl is invalid, make sure the new one is marked invalid and 962 // don't do any other checking. 963 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 964 return New->setInvalidDecl(); 965 966 // Verify the old decl was also a variable. 967 VarDecl *Old = dyn_cast<VarDecl>(OldD); 968 if (!Old) { 969 Diag(New->getLocation(), diag::err_redefinition_different_kind) 970 << New->getDeclName(); 971 Diag(OldD->getLocation(), diag::note_previous_definition); 972 return New->setInvalidDecl(); 973 } 974 975 MergeAttributes(New, Old, Context); 976 977 // Merge the types 978 QualType MergedT; 979 if (getLangOptions().CPlusPlus) { 980 if (Context.hasSameType(New->getType(), Old->getType())) 981 MergedT = New->getType(); 982 } else { 983 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 984 } 985 if (MergedT.isNull()) { 986 Diag(New->getLocation(), diag::err_redefinition_different_type) 987 << New->getDeclName(); 988 Diag(Old->getLocation(), diag::note_previous_definition); 989 return New->setInvalidDecl(); 990 } 991 New->setType(MergedT); 992 993 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 994 if (New->getStorageClass() == VarDecl::Static && 995 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 996 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 997 Diag(Old->getLocation(), diag::note_previous_definition); 998 return New->setInvalidDecl(); 999 } 1000 // C99 6.2.2p4: 1001 // For an identifier declared with the storage-class specifier 1002 // extern in a scope in which a prior declaration of that 1003 // identifier is visible,23) if the prior declaration specifies 1004 // internal or external linkage, the linkage of the identifier at 1005 // the later declaration is the same as the linkage specified at 1006 // the prior declaration. If no prior declaration is visible, or 1007 // if the prior declaration specifies no linkage, then the 1008 // identifier has external linkage. 1009 if (New->hasExternalStorage() && Old->hasLinkage()) 1010 /* Okay */; 1011 else if (New->getStorageClass() != VarDecl::Static && 1012 Old->getStorageClass() == VarDecl::Static) { 1013 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1014 Diag(Old->getLocation(), diag::note_previous_definition); 1015 return New->setInvalidDecl(); 1016 } 1017 1018 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1019 1020 // FIXME: The test for external storage here seems wrong? We still 1021 // need to check for mismatches. 1022 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1023 // Don't complain about out-of-line definitions of static members. 1024 !(Old->getLexicalDeclContext()->isRecord() && 1025 !New->getLexicalDeclContext()->isRecord())) { 1026 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1027 Diag(Old->getLocation(), diag::note_previous_definition); 1028 return New->setInvalidDecl(); 1029 } 1030 1031 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1032 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1033 Diag(Old->getLocation(), diag::note_previous_definition); 1034 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1035 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1036 Diag(Old->getLocation(), diag::note_previous_definition); 1037 } 1038 1039 // Keep a chain of previous declarations. 1040 New->setPreviousDeclaration(Old); 1041} 1042 1043/// CheckFallThrough - Check that we don't fall off the end of a 1044/// Statement that should return a value. 1045/// 1046/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1047/// MaybeFallThrough iff we might or might not fall off the end and 1048/// NeverFallThrough iff we never fall off the end of the statement. We assume 1049/// that functions not marked noreturn will return. 1050Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1051 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1052 1053 // FIXME: They should never return 0, fix that, delete this code. 1054 if (cfg == 0) 1055 return NeverFallThrough; 1056 // The CFG leaves in dead things, and we don't want to dead code paths to 1057 // confuse us, so we mark all live things first. 1058 std::queue<CFGBlock*> workq; 1059 llvm::BitVector live(cfg->getNumBlockIDs()); 1060 // Prep work queue 1061 workq.push(&cfg->getEntry()); 1062 // Solve 1063 while (!workq.empty()) { 1064 CFGBlock *item = workq.front(); 1065 workq.pop(); 1066 live.set(item->getBlockID()); 1067 for (CFGBlock::succ_iterator I=item->succ_begin(), 1068 E=item->succ_end(); 1069 I != E; 1070 ++I) { 1071 if ((*I) && !live[(*I)->getBlockID()]) { 1072 live.set((*I)->getBlockID()); 1073 workq.push(*I); 1074 } 1075 } 1076 } 1077 1078 // Now we know what is live, we check the live precessors of the exit block 1079 // and look for fall through paths, being careful to ignore normal returns, 1080 // and exceptional paths. 1081 bool HasLiveReturn = false; 1082 bool HasFakeEdge = false; 1083 bool HasPlainEdge = false; 1084 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1085 E = cfg->getExit().pred_end(); 1086 I != E; 1087 ++I) { 1088 CFGBlock& B = **I; 1089 if (!live[B.getBlockID()]) 1090 continue; 1091 if (B.size() == 0) { 1092 // A labeled empty statement, or the entry block... 1093 HasPlainEdge = true; 1094 continue; 1095 } 1096 Stmt *S = B[B.size()-1]; 1097 if (isa<ReturnStmt>(S)) { 1098 HasLiveReturn = true; 1099 continue; 1100 } 1101 if (isa<ObjCAtThrowStmt>(S)) { 1102 HasFakeEdge = true; 1103 continue; 1104 } 1105 if (isa<CXXThrowExpr>(S)) { 1106 HasFakeEdge = true; 1107 continue; 1108 } 1109 bool NoReturnEdge = false; 1110 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1111 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1112 if (CEE->getType().getNoReturnAttr()) { 1113 NoReturnEdge = true; 1114 HasFakeEdge = true; 1115 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1116 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1117 if (FD->hasAttr<NoReturnAttr>()) { 1118 NoReturnEdge = true; 1119 HasFakeEdge = true; 1120 } 1121 } 1122 } 1123 } 1124 // FIXME: Add noreturn message sends. 1125 if (NoReturnEdge == false) 1126 HasPlainEdge = true; 1127 } 1128 if (!HasPlainEdge) 1129 return NeverFallThrough; 1130 if (HasFakeEdge || HasLiveReturn) 1131 return MaybeFallThrough; 1132 // This says AlwaysFallThrough for calls to functions that are not marked 1133 // noreturn, that don't return. If people would like this warning to be more 1134 // accurate, such functions should be marked as noreturn. 1135 return AlwaysFallThrough; 1136} 1137 1138/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1139/// function that should return a value. Check that we don't fall off the end 1140/// of a noreturn function. We assume that functions and blocks not marked 1141/// noreturn will return. 1142void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1143 // FIXME: Would be nice if we had a better way to control cascading errors, 1144 // but for now, avoid them. The problem is that when Parse sees: 1145 // int foo() { return a; } 1146 // The return is eaten and the Sema code sees just: 1147 // int foo() { } 1148 // which this code would then warn about. 1149 if (getDiagnostics().hasErrorOccurred()) 1150 return; 1151 bool ReturnsVoid = false; 1152 bool HasNoReturn = false; 1153 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1154 if (FD->getResultType()->isVoidType()) 1155 ReturnsVoid = true; 1156 if (FD->hasAttr<NoReturnAttr>()) 1157 HasNoReturn = true; 1158 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1159 if (MD->getResultType()->isVoidType()) 1160 ReturnsVoid = true; 1161 if (MD->hasAttr<NoReturnAttr>()) 1162 HasNoReturn = true; 1163 } 1164 1165 // Short circuit for compilation speed. 1166 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1167 == Diagnostic::Ignored || ReturnsVoid) 1168 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1169 == Diagnostic::Ignored || !HasNoReturn) 1170 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1171 == Diagnostic::Ignored || !ReturnsVoid)) 1172 return; 1173 // FIXME: Funtion try block 1174 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1175 switch (CheckFallThrough(Body)) { 1176 case MaybeFallThrough: 1177 if (HasNoReturn) 1178 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1179 else if (!ReturnsVoid) 1180 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1181 break; 1182 case AlwaysFallThrough: 1183 if (HasNoReturn) 1184 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1185 else if (!ReturnsVoid) 1186 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1187 break; 1188 case NeverFallThrough: 1189 if (ReturnsVoid) 1190 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1191 break; 1192 } 1193 } 1194} 1195 1196/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1197/// that should return a value. Check that we don't fall off the end of a 1198/// noreturn block. We assume that functions and blocks not marked noreturn 1199/// will return. 1200void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1201 // FIXME: Would be nice if we had a better way to control cascading errors, 1202 // but for now, avoid them. The problem is that when Parse sees: 1203 // int foo() { return a; } 1204 // The return is eaten and the Sema code sees just: 1205 // int foo() { } 1206 // which this code would then warn about. 1207 if (getDiagnostics().hasErrorOccurred()) 1208 return; 1209 bool ReturnsVoid = false; 1210 bool HasNoReturn = false; 1211 if (const FunctionType *FT = BlockTy->getPointeeType()->getAsFunctionType()) { 1212 if (FT->getResultType()->isVoidType()) 1213 ReturnsVoid = true; 1214 if (FT->getNoReturnAttr()) 1215 HasNoReturn = true; 1216 } 1217 1218 // Short circuit for compilation speed. 1219 if (ReturnsVoid 1220 && !HasNoReturn 1221 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1222 == Diagnostic::Ignored || !ReturnsVoid)) 1223 return; 1224 // FIXME: Funtion try block 1225 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1226 switch (CheckFallThrough(Body)) { 1227 case MaybeFallThrough: 1228 if (HasNoReturn) 1229 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1230 else if (!ReturnsVoid) 1231 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1232 break; 1233 case AlwaysFallThrough: 1234 if (HasNoReturn) 1235 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1236 else if (!ReturnsVoid) 1237 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1238 break; 1239 case NeverFallThrough: 1240 if (ReturnsVoid) 1241 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1242 break; 1243 } 1244 } 1245} 1246 1247/// CheckParmsForFunctionDef - Check that the parameters of the given 1248/// function are appropriate for the definition of a function. This 1249/// takes care of any checks that cannot be performed on the 1250/// declaration itself, e.g., that the types of each of the function 1251/// parameters are complete. 1252bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1253 bool HasInvalidParm = false; 1254 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1255 ParmVarDecl *Param = FD->getParamDecl(p); 1256 1257 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1258 // function declarator that is part of a function definition of 1259 // that function shall not have incomplete type. 1260 // 1261 // This is also C++ [dcl.fct]p6. 1262 if (!Param->isInvalidDecl() && 1263 RequireCompleteType(Param->getLocation(), Param->getType(), 1264 diag::err_typecheck_decl_incomplete_type)) { 1265 Param->setInvalidDecl(); 1266 HasInvalidParm = true; 1267 } 1268 1269 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1270 // declaration of each parameter shall include an identifier. 1271 if (Param->getIdentifier() == 0 && 1272 !Param->isImplicit() && 1273 !getLangOptions().CPlusPlus) 1274 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1275 } 1276 1277 return HasInvalidParm; 1278} 1279 1280/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1281/// no declarator (e.g. "struct foo;") is parsed. 1282Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1283 // FIXME: Error on auto/register at file scope 1284 // FIXME: Error on inline/virtual/explicit 1285 // FIXME: Error on invalid restrict 1286 // FIXME: Warn on useless __thread 1287 // FIXME: Warn on useless const/volatile 1288 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1289 // FIXME: Warn on useless attributes 1290 TagDecl *Tag = 0; 1291 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1292 DS.getTypeSpecType() == DeclSpec::TST_struct || 1293 DS.getTypeSpecType() == DeclSpec::TST_union || 1294 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1295 if (!DS.getTypeRep()) // We probably had an error 1296 return DeclPtrTy(); 1297 1298 // Note that the above type specs guarantee that the 1299 // type rep is a Decl, whereas in many of the others 1300 // it's a Type. 1301 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1302 } 1303 1304 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1305 if (!Record->getDeclName() && Record->isDefinition() && 1306 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1307 if (getLangOptions().CPlusPlus || 1308 Record->getDeclContext()->isRecord()) 1309 return BuildAnonymousStructOrUnion(S, DS, Record); 1310 1311 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1312 << DS.getSourceRange(); 1313 } 1314 1315 // Microsoft allows unnamed struct/union fields. Don't complain 1316 // about them. 1317 // FIXME: Should we support Microsoft's extensions in this area? 1318 if (Record->getDeclName() && getLangOptions().Microsoft) 1319 return DeclPtrTy::make(Tag); 1320 } 1321 1322 if (!DS.isMissingDeclaratorOk() && 1323 DS.getTypeSpecType() != DeclSpec::TST_error) { 1324 // Warn about typedefs of enums without names, since this is an 1325 // extension in both Microsoft an GNU. 1326 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1327 Tag && isa<EnumDecl>(Tag)) { 1328 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1329 << DS.getSourceRange(); 1330 return DeclPtrTy::make(Tag); 1331 } 1332 1333 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1334 << DS.getSourceRange(); 1335 return DeclPtrTy(); 1336 } 1337 1338 return DeclPtrTy::make(Tag); 1339} 1340 1341/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1342/// anonymous struct or union AnonRecord into the owning context Owner 1343/// and scope S. This routine will be invoked just after we realize 1344/// that an unnamed union or struct is actually an anonymous union or 1345/// struct, e.g., 1346/// 1347/// @code 1348/// union { 1349/// int i; 1350/// float f; 1351/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1352/// // f into the surrounding scope.x 1353/// @endcode 1354/// 1355/// This routine is recursive, injecting the names of nested anonymous 1356/// structs/unions into the owning context and scope as well. 1357bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1358 RecordDecl *AnonRecord) { 1359 bool Invalid = false; 1360 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1361 FEnd = AnonRecord->field_end(); 1362 F != FEnd; ++F) { 1363 if ((*F)->getDeclName()) { 1364 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1365 LookupOrdinaryName, true); 1366 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1367 // C++ [class.union]p2: 1368 // The names of the members of an anonymous union shall be 1369 // distinct from the names of any other entity in the 1370 // scope in which the anonymous union is declared. 1371 unsigned diagKind 1372 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1373 : diag::err_anonymous_struct_member_redecl; 1374 Diag((*F)->getLocation(), diagKind) 1375 << (*F)->getDeclName(); 1376 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1377 Invalid = true; 1378 } else { 1379 // C++ [class.union]p2: 1380 // For the purpose of name lookup, after the anonymous union 1381 // definition, the members of the anonymous union are 1382 // considered to have been defined in the scope in which the 1383 // anonymous union is declared. 1384 Owner->makeDeclVisibleInContext(*F); 1385 S->AddDecl(DeclPtrTy::make(*F)); 1386 IdResolver.AddDecl(*F); 1387 } 1388 } else if (const RecordType *InnerRecordType 1389 = (*F)->getType()->getAs<RecordType>()) { 1390 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1391 if (InnerRecord->isAnonymousStructOrUnion()) 1392 Invalid = Invalid || 1393 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1394 } 1395 } 1396 1397 return Invalid; 1398} 1399 1400/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1401/// anonymous structure or union. Anonymous unions are a C++ feature 1402/// (C++ [class.union]) and a GNU C extension; anonymous structures 1403/// are a GNU C and GNU C++ extension. 1404Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1405 RecordDecl *Record) { 1406 DeclContext *Owner = Record->getDeclContext(); 1407 1408 // Diagnose whether this anonymous struct/union is an extension. 1409 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1410 Diag(Record->getLocation(), diag::ext_anonymous_union); 1411 else if (!Record->isUnion()) 1412 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1413 1414 // C and C++ require different kinds of checks for anonymous 1415 // structs/unions. 1416 bool Invalid = false; 1417 if (getLangOptions().CPlusPlus) { 1418 const char* PrevSpec = 0; 1419 unsigned DiagID; 1420 // C++ [class.union]p3: 1421 // Anonymous unions declared in a named namespace or in the 1422 // global namespace shall be declared static. 1423 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1424 (isa<TranslationUnitDecl>(Owner) || 1425 (isa<NamespaceDecl>(Owner) && 1426 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1427 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1428 Invalid = true; 1429 1430 // Recover by adding 'static'. 1431 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1432 PrevSpec, DiagID); 1433 } 1434 // C++ [class.union]p3: 1435 // A storage class is not allowed in a declaration of an 1436 // anonymous union in a class scope. 1437 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1438 isa<RecordDecl>(Owner)) { 1439 Diag(DS.getStorageClassSpecLoc(), 1440 diag::err_anonymous_union_with_storage_spec); 1441 Invalid = true; 1442 1443 // Recover by removing the storage specifier. 1444 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1445 PrevSpec, DiagID); 1446 } 1447 1448 // C++ [class.union]p2: 1449 // The member-specification of an anonymous union shall only 1450 // define non-static data members. [Note: nested types and 1451 // functions cannot be declared within an anonymous union. ] 1452 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1453 MemEnd = Record->decls_end(); 1454 Mem != MemEnd; ++Mem) { 1455 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1456 // C++ [class.union]p3: 1457 // An anonymous union shall not have private or protected 1458 // members (clause 11). 1459 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1460 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1461 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1462 Invalid = true; 1463 } 1464 } else if ((*Mem)->isImplicit()) { 1465 // Any implicit members are fine. 1466 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1467 // This is a type that showed up in an 1468 // elaborated-type-specifier inside the anonymous struct or 1469 // union, but which actually declares a type outside of the 1470 // anonymous struct or union. It's okay. 1471 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1472 if (!MemRecord->isAnonymousStructOrUnion() && 1473 MemRecord->getDeclName()) { 1474 // This is a nested type declaration. 1475 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1476 << (int)Record->isUnion(); 1477 Invalid = true; 1478 } 1479 } else { 1480 // We have something that isn't a non-static data 1481 // member. Complain about it. 1482 unsigned DK = diag::err_anonymous_record_bad_member; 1483 if (isa<TypeDecl>(*Mem)) 1484 DK = diag::err_anonymous_record_with_type; 1485 else if (isa<FunctionDecl>(*Mem)) 1486 DK = diag::err_anonymous_record_with_function; 1487 else if (isa<VarDecl>(*Mem)) 1488 DK = diag::err_anonymous_record_with_static; 1489 Diag((*Mem)->getLocation(), DK) 1490 << (int)Record->isUnion(); 1491 Invalid = true; 1492 } 1493 } 1494 } 1495 1496 if (!Record->isUnion() && !Owner->isRecord()) { 1497 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1498 << (int)getLangOptions().CPlusPlus; 1499 Invalid = true; 1500 } 1501 1502 // Create a declaration for this anonymous struct/union. 1503 NamedDecl *Anon = 0; 1504 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1505 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1506 /*IdentifierInfo=*/0, 1507 Context.getTypeDeclType(Record), 1508 // FIXME: Type source info. 1509 /*DInfo=*/0, 1510 /*BitWidth=*/0, /*Mutable=*/false); 1511 Anon->setAccess(AS_public); 1512 if (getLangOptions().CPlusPlus) 1513 FieldCollector->Add(cast<FieldDecl>(Anon)); 1514 } else { 1515 VarDecl::StorageClass SC; 1516 switch (DS.getStorageClassSpec()) { 1517 default: assert(0 && "Unknown storage class!"); 1518 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1519 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1520 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1521 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1522 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1523 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1524 case DeclSpec::SCS_mutable: 1525 // mutable can only appear on non-static class members, so it's always 1526 // an error here 1527 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1528 Invalid = true; 1529 SC = VarDecl::None; 1530 break; 1531 } 1532 1533 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1534 /*IdentifierInfo=*/0, 1535 Context.getTypeDeclType(Record), 1536 // FIXME: Type source info. 1537 /*DInfo=*/0, 1538 SC); 1539 } 1540 Anon->setImplicit(); 1541 1542 // Add the anonymous struct/union object to the current 1543 // context. We'll be referencing this object when we refer to one of 1544 // its members. 1545 Owner->addDecl(Anon); 1546 1547 // Inject the members of the anonymous struct/union into the owning 1548 // context and into the identifier resolver chain for name lookup 1549 // purposes. 1550 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1551 Invalid = true; 1552 1553 // Mark this as an anonymous struct/union type. Note that we do not 1554 // do this until after we have already checked and injected the 1555 // members of this anonymous struct/union type, because otherwise 1556 // the members could be injected twice: once by DeclContext when it 1557 // builds its lookup table, and once by 1558 // InjectAnonymousStructOrUnionMembers. 1559 Record->setAnonymousStructOrUnion(true); 1560 1561 if (Invalid) 1562 Anon->setInvalidDecl(); 1563 1564 return DeclPtrTy::make(Anon); 1565} 1566 1567 1568/// GetNameForDeclarator - Determine the full declaration name for the 1569/// given Declarator. 1570DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1571 switch (D.getKind()) { 1572 case Declarator::DK_Abstract: 1573 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1574 return DeclarationName(); 1575 1576 case Declarator::DK_Normal: 1577 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1578 return DeclarationName(D.getIdentifier()); 1579 1580 case Declarator::DK_Constructor: { 1581 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1582 return Context.DeclarationNames.getCXXConstructorName( 1583 Context.getCanonicalType(Ty)); 1584 } 1585 1586 case Declarator::DK_Destructor: { 1587 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1588 return Context.DeclarationNames.getCXXDestructorName( 1589 Context.getCanonicalType(Ty)); 1590 } 1591 1592 case Declarator::DK_Conversion: { 1593 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1594 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1595 return Context.DeclarationNames.getCXXConversionFunctionName( 1596 Context.getCanonicalType(Ty)); 1597 } 1598 1599 case Declarator::DK_Operator: 1600 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1601 return Context.DeclarationNames.getCXXOperatorName( 1602 D.getOverloadedOperator()); 1603 } 1604 1605 assert(false && "Unknown name kind"); 1606 return DeclarationName(); 1607} 1608 1609/// isNearlyMatchingFunction - Determine whether the C++ functions 1610/// Declaration and Definition are "nearly" matching. This heuristic 1611/// is used to improve diagnostics in the case where an out-of-line 1612/// function definition doesn't match any declaration within 1613/// the class or namespace. 1614static bool isNearlyMatchingFunction(ASTContext &Context, 1615 FunctionDecl *Declaration, 1616 FunctionDecl *Definition) { 1617 if (Declaration->param_size() != Definition->param_size()) 1618 return false; 1619 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1620 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1621 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1622 1623 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1624 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1625 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1626 return false; 1627 } 1628 1629 return true; 1630} 1631 1632Sema::DeclPtrTy 1633Sema::HandleDeclarator(Scope *S, Declarator &D, 1634 MultiTemplateParamsArg TemplateParamLists, 1635 bool IsFunctionDefinition) { 1636 DeclarationName Name = GetNameForDeclarator(D); 1637 1638 // All of these full declarators require an identifier. If it doesn't have 1639 // one, the ParsedFreeStandingDeclSpec action should be used. 1640 if (!Name) { 1641 if (!D.isInvalidType()) // Reject this if we think it is valid. 1642 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1643 diag::err_declarator_need_ident) 1644 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1645 return DeclPtrTy(); 1646 } 1647 1648 // The scope passed in may not be a decl scope. Zip up the scope tree until 1649 // we find one that is. 1650 while ((S->getFlags() & Scope::DeclScope) == 0 || 1651 (S->getFlags() & Scope::TemplateParamScope) != 0) 1652 S = S->getParent(); 1653 1654 // If this is an out-of-line definition of a member of a class template 1655 // or class template partial specialization, we may need to rebuild the 1656 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1657 // for more information. 1658 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1659 // handle expressions properly. 1660 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1661 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1662 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1663 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1664 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1665 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1666 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1667 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1668 // FIXME: Preserve type source info. 1669 QualType T = GetTypeFromParser(DS.getTypeRep()); 1670 EnterDeclaratorContext(S, DC); 1671 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1672 ExitDeclaratorContext(S); 1673 if (T.isNull()) 1674 return DeclPtrTy(); 1675 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1676 } 1677 } 1678 1679 DeclContext *DC; 1680 NamedDecl *PrevDecl; 1681 NamedDecl *New; 1682 1683 DeclaratorInfo *DInfo = 0; 1684 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1685 1686 // See if this is a redefinition of a variable in the same scope. 1687 if (D.getCXXScopeSpec().isInvalid()) { 1688 DC = CurContext; 1689 PrevDecl = 0; 1690 D.setInvalidType(); 1691 } else if (!D.getCXXScopeSpec().isSet()) { 1692 LookupNameKind NameKind = LookupOrdinaryName; 1693 1694 // If the declaration we're planning to build will be a function 1695 // or object with linkage, then look for another declaration with 1696 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1697 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1698 /* Do nothing*/; 1699 else if (R->isFunctionType()) { 1700 if (CurContext->isFunctionOrMethod() || 1701 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1702 NameKind = LookupRedeclarationWithLinkage; 1703 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1704 NameKind = LookupRedeclarationWithLinkage; 1705 else if (CurContext->getLookupContext()->isTranslationUnit() && 1706 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1707 NameKind = LookupRedeclarationWithLinkage; 1708 1709 DC = CurContext; 1710 PrevDecl = LookupName(S, Name, NameKind, true, 1711 NameKind == LookupRedeclarationWithLinkage, 1712 D.getIdentifierLoc()); 1713 } else { // Something like "int foo::x;" 1714 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1715 1716 if (!DC) { 1717 // If we could not compute the declaration context, it's because the 1718 // declaration context is dependent but does not refer to a class, 1719 // class template, or class template partial specialization. Complain 1720 // and return early, to avoid the coming semantic disaster. 1721 Diag(D.getIdentifierLoc(), 1722 diag::err_template_qualified_declarator_no_match) 1723 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1724 << D.getCXXScopeSpec().getRange(); 1725 return DeclPtrTy(); 1726 } 1727 1728 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1729 1730 // C++ 7.3.1.2p2: 1731 // Members (including explicit specializations of templates) of a named 1732 // namespace can also be defined outside that namespace by explicit 1733 // qualification of the name being defined, provided that the entity being 1734 // defined was already declared in the namespace and the definition appears 1735 // after the point of declaration in a namespace that encloses the 1736 // declarations namespace. 1737 // 1738 // Note that we only check the context at this point. We don't yet 1739 // have enough information to make sure that PrevDecl is actually 1740 // the declaration we want to match. For example, given: 1741 // 1742 // class X { 1743 // void f(); 1744 // void f(float); 1745 // }; 1746 // 1747 // void X::f(int) { } // ill-formed 1748 // 1749 // In this case, PrevDecl will point to the overload set 1750 // containing the two f's declared in X, but neither of them 1751 // matches. 1752 1753 // First check whether we named the global scope. 1754 if (isa<TranslationUnitDecl>(DC)) { 1755 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1756 << Name << D.getCXXScopeSpec().getRange(); 1757 } else if (!CurContext->Encloses(DC)) { 1758 // The qualifying scope doesn't enclose the original declaration. 1759 // Emit diagnostic based on current scope. 1760 SourceLocation L = D.getIdentifierLoc(); 1761 SourceRange R = D.getCXXScopeSpec().getRange(); 1762 if (isa<FunctionDecl>(CurContext)) 1763 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1764 else 1765 Diag(L, diag::err_invalid_declarator_scope) 1766 << Name << cast<NamedDecl>(DC) << R; 1767 D.setInvalidType(); 1768 } 1769 } 1770 1771 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1772 // Maybe we will complain about the shadowed template parameter. 1773 if (!D.isInvalidType()) 1774 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1775 D.setInvalidType(); 1776 1777 // Just pretend that we didn't see the previous declaration. 1778 PrevDecl = 0; 1779 } 1780 1781 // In C++, the previous declaration we find might be a tag type 1782 // (class or enum). In this case, the new declaration will hide the 1783 // tag type. Note that this does does not apply if we're declaring a 1784 // typedef (C++ [dcl.typedef]p4). 1785 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1786 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1787 PrevDecl = 0; 1788 1789 bool Redeclaration = false; 1790 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1791 if (TemplateParamLists.size()) { 1792 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1793 return DeclPtrTy(); 1794 } 1795 1796 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1797 } else if (R->isFunctionType()) { 1798 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1799 move(TemplateParamLists), 1800 IsFunctionDefinition, Redeclaration); 1801 } else { 1802 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1803 move(TemplateParamLists), 1804 Redeclaration); 1805 } 1806 1807 if (New == 0) 1808 return DeclPtrTy(); 1809 1810 // If this has an identifier and is not an invalid redeclaration, 1811 // add it to the scope stack. 1812 if (Name && !(Redeclaration && New->isInvalidDecl())) 1813 PushOnScopeChains(New, S); 1814 1815 return DeclPtrTy::make(New); 1816} 1817 1818/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1819/// types into constant array types in certain situations which would otherwise 1820/// be errors (for GCC compatibility). 1821static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1822 ASTContext &Context, 1823 bool &SizeIsNegative) { 1824 // This method tries to turn a variable array into a constant 1825 // array even when the size isn't an ICE. This is necessary 1826 // for compatibility with code that depends on gcc's buggy 1827 // constant expression folding, like struct {char x[(int)(char*)2];} 1828 SizeIsNegative = false; 1829 1830 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1831 QualType Pointee = PTy->getPointeeType(); 1832 QualType FixedType = 1833 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1834 if (FixedType.isNull()) return FixedType; 1835 FixedType = Context.getPointerType(FixedType); 1836 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1837 return FixedType; 1838 } 1839 1840 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1841 if (!VLATy) 1842 return QualType(); 1843 // FIXME: We should probably handle this case 1844 if (VLATy->getElementType()->isVariablyModifiedType()) 1845 return QualType(); 1846 1847 Expr::EvalResult EvalResult; 1848 if (!VLATy->getSizeExpr() || 1849 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1850 !EvalResult.Val.isInt()) 1851 return QualType(); 1852 1853 llvm::APSInt &Res = EvalResult.Val.getInt(); 1854 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1855 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1856 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1857 // so as to transfer ownership to the ConstantArrayWithExpr. 1858 // Alternatively, we could "clone" it (how?). 1859 // Since we don't know how to do things above, we just use the 1860 // very same Expr*. 1861 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1862 Res, ArySizeExpr, 1863 ArrayType::Normal, 0, 1864 VLATy->getBracketsRange()); 1865 } 1866 1867 SizeIsNegative = true; 1868 return QualType(); 1869} 1870 1871/// \brief Register the given locally-scoped external C declaration so 1872/// that it can be found later for redeclarations 1873void 1874Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1875 Scope *S) { 1876 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1877 "Decl is not a locally-scoped decl!"); 1878 // Note that we have a locally-scoped external with this name. 1879 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1880 1881 if (!PrevDecl) 1882 return; 1883 1884 // If there was a previous declaration of this variable, it may be 1885 // in our identifier chain. Update the identifier chain with the new 1886 // declaration. 1887 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1888 // The previous declaration was found on the identifer resolver 1889 // chain, so remove it from its scope. 1890 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1891 S = S->getParent(); 1892 1893 if (S) 1894 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1895 } 1896} 1897 1898/// \brief Diagnose function specifiers on a declaration of an identifier that 1899/// does not identify a function. 1900void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1901 // FIXME: We should probably indicate the identifier in question to avoid 1902 // confusion for constructs like "inline int a(), b;" 1903 if (D.getDeclSpec().isInlineSpecified()) 1904 Diag(D.getDeclSpec().getInlineSpecLoc(), 1905 diag::err_inline_non_function); 1906 1907 if (D.getDeclSpec().isVirtualSpecified()) 1908 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1909 diag::err_virtual_non_function); 1910 1911 if (D.getDeclSpec().isExplicitSpecified()) 1912 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1913 diag::err_explicit_non_function); 1914} 1915 1916NamedDecl* 1917Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1918 QualType R, DeclaratorInfo *DInfo, 1919 Decl* PrevDecl, bool &Redeclaration) { 1920 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1921 if (D.getCXXScopeSpec().isSet()) { 1922 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1923 << D.getCXXScopeSpec().getRange(); 1924 D.setInvalidType(); 1925 // Pretend we didn't see the scope specifier. 1926 DC = 0; 1927 } 1928 1929 if (getLangOptions().CPlusPlus) { 1930 // Check that there are no default arguments (C++ only). 1931 CheckExtraCXXDefaultArguments(D); 1932 } 1933 1934 DiagnoseFunctionSpecifiers(D); 1935 1936 if (D.getDeclSpec().isThreadSpecified()) 1937 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1938 1939 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1940 if (!NewTD) return 0; 1941 1942 if (D.isInvalidType()) 1943 NewTD->setInvalidDecl(); 1944 1945 // Handle attributes prior to checking for duplicates in MergeVarDecl 1946 ProcessDeclAttributes(S, NewTD, D); 1947 // Merge the decl with the existing one if appropriate. If the decl is 1948 // in an outer scope, it isn't the same thing. 1949 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1950 Redeclaration = true; 1951 MergeTypeDefDecl(NewTD, PrevDecl); 1952 } 1953 1954 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1955 // then it shall have block scope. 1956 QualType T = NewTD->getUnderlyingType(); 1957 if (T->isVariablyModifiedType()) { 1958 CurFunctionNeedsScopeChecking = true; 1959 1960 if (S->getFnParent() == 0) { 1961 bool SizeIsNegative; 1962 QualType FixedTy = 1963 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1964 if (!FixedTy.isNull()) { 1965 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1966 NewTD->setUnderlyingType(FixedTy); 1967 } else { 1968 if (SizeIsNegative) 1969 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1970 else if (T->isVariableArrayType()) 1971 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1972 else 1973 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1974 NewTD->setInvalidDecl(); 1975 } 1976 } 1977 } 1978 1979 // If this is the C FILE type, notify the AST context. 1980 if (IdentifierInfo *II = NewTD->getIdentifier()) 1981 if (!NewTD->isInvalidDecl() && 1982 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1983 if (II->isStr("FILE")) 1984 Context.setFILEDecl(NewTD); 1985 else if (II->isStr("jmp_buf")) 1986 Context.setjmp_bufDecl(NewTD); 1987 else if (II->isStr("sigjmp_buf")) 1988 Context.setsigjmp_bufDecl(NewTD); 1989 } 1990 1991 return NewTD; 1992} 1993 1994/// \brief Determines whether the given declaration is an out-of-scope 1995/// previous declaration. 1996/// 1997/// This routine should be invoked when name lookup has found a 1998/// previous declaration (PrevDecl) that is not in the scope where a 1999/// new declaration by the same name is being introduced. If the new 2000/// declaration occurs in a local scope, previous declarations with 2001/// linkage may still be considered previous declarations (C99 2002/// 6.2.2p4-5, C++ [basic.link]p6). 2003/// 2004/// \param PrevDecl the previous declaration found by name 2005/// lookup 2006/// 2007/// \param DC the context in which the new declaration is being 2008/// declared. 2009/// 2010/// \returns true if PrevDecl is an out-of-scope previous declaration 2011/// for a new delcaration with the same name. 2012static bool 2013isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2014 ASTContext &Context) { 2015 if (!PrevDecl) 2016 return 0; 2017 2018 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2019 // case we need to check each of the overloaded functions. 2020 if (!PrevDecl->hasLinkage()) 2021 return false; 2022 2023 if (Context.getLangOptions().CPlusPlus) { 2024 // C++ [basic.link]p6: 2025 // If there is a visible declaration of an entity with linkage 2026 // having the same name and type, ignoring entities declared 2027 // outside the innermost enclosing namespace scope, the block 2028 // scope declaration declares that same entity and receives the 2029 // linkage of the previous declaration. 2030 DeclContext *OuterContext = DC->getLookupContext(); 2031 if (!OuterContext->isFunctionOrMethod()) 2032 // This rule only applies to block-scope declarations. 2033 return false; 2034 else { 2035 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2036 if (PrevOuterContext->isRecord()) 2037 // We found a member function: ignore it. 2038 return false; 2039 else { 2040 // Find the innermost enclosing namespace for the new and 2041 // previous declarations. 2042 while (!OuterContext->isFileContext()) 2043 OuterContext = OuterContext->getParent(); 2044 while (!PrevOuterContext->isFileContext()) 2045 PrevOuterContext = PrevOuterContext->getParent(); 2046 2047 // The previous declaration is in a different namespace, so it 2048 // isn't the same function. 2049 if (OuterContext->getPrimaryContext() != 2050 PrevOuterContext->getPrimaryContext()) 2051 return false; 2052 } 2053 } 2054 } 2055 2056 return true; 2057} 2058 2059NamedDecl* 2060Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2061 QualType R, DeclaratorInfo *DInfo, 2062 NamedDecl* PrevDecl, 2063 MultiTemplateParamsArg TemplateParamLists, 2064 bool &Redeclaration) { 2065 DeclarationName Name = GetNameForDeclarator(D); 2066 2067 // Check that there are no default arguments (C++ only). 2068 if (getLangOptions().CPlusPlus) 2069 CheckExtraCXXDefaultArguments(D); 2070 2071 VarDecl *NewVD; 2072 VarDecl::StorageClass SC; 2073 switch (D.getDeclSpec().getStorageClassSpec()) { 2074 default: assert(0 && "Unknown storage class!"); 2075 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2076 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2077 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2078 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2079 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2080 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2081 case DeclSpec::SCS_mutable: 2082 // mutable can only appear on non-static class members, so it's always 2083 // an error here 2084 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2085 D.setInvalidType(); 2086 SC = VarDecl::None; 2087 break; 2088 } 2089 2090 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2091 if (!II) { 2092 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2093 << Name.getAsString(); 2094 return 0; 2095 } 2096 2097 DiagnoseFunctionSpecifiers(D); 2098 2099 if (!DC->isRecord() && S->getFnParent() == 0) { 2100 // C99 6.9p2: The storage-class specifiers auto and register shall not 2101 // appear in the declaration specifiers in an external declaration. 2102 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2103 2104 // If this is a register variable with an asm label specified, then this 2105 // is a GNU extension. 2106 if (SC == VarDecl::Register && D.getAsmLabel()) 2107 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2108 else 2109 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2110 D.setInvalidType(); 2111 } 2112 } 2113 if (DC->isRecord() && !CurContext->isRecord()) { 2114 // This is an out-of-line definition of a static data member. 2115 if (SC == VarDecl::Static) { 2116 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2117 diag::err_static_out_of_line) 2118 << CodeModificationHint::CreateRemoval( 2119 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2120 } else if (SC == VarDecl::None) 2121 SC = VarDecl::Static; 2122 } 2123 if (SC == VarDecl::Static) { 2124 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2125 if (RD->isLocalClass()) 2126 Diag(D.getIdentifierLoc(), 2127 diag::err_static_data_member_not_allowed_in_local_class) 2128 << Name << RD->getDeclName(); 2129 } 2130 } 2131 2132 // Match up the template parameter lists with the scope specifier, then 2133 // determine whether we have a template or a template specialization. 2134 if (TemplateParameterList *TemplateParams 2135 = MatchTemplateParametersToScopeSpecifier( 2136 D.getDeclSpec().getSourceRange().getBegin(), 2137 D.getCXXScopeSpec(), 2138 (TemplateParameterList**)TemplateParamLists.get(), 2139 TemplateParamLists.size())) { 2140 if (TemplateParams->size() > 0) { 2141 // There is no such thing as a variable template. 2142 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2143 << II 2144 << SourceRange(TemplateParams->getTemplateLoc(), 2145 TemplateParams->getRAngleLoc()); 2146 return 0; 2147 } else { 2148 // There is an extraneous 'template<>' for this variable. Complain 2149 // about it, but allow the declaration of the variable. 2150 Diag(TemplateParams->getTemplateLoc(), 2151 diag::err_template_variable_noparams) 2152 << II 2153 << SourceRange(TemplateParams->getTemplateLoc(), 2154 TemplateParams->getRAngleLoc()); 2155 } 2156 } 2157 2158 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2159 II, R, DInfo, SC); 2160 2161 if (D.isInvalidType()) 2162 NewVD->setInvalidDecl(); 2163 2164 if (D.getDeclSpec().isThreadSpecified()) { 2165 if (NewVD->hasLocalStorage()) 2166 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2167 else if (!Context.Target.isTLSSupported()) 2168 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2169 else 2170 NewVD->setThreadSpecified(true); 2171 } 2172 2173 // Set the lexical context. If the declarator has a C++ scope specifier, the 2174 // lexical context will be different from the semantic context. 2175 NewVD->setLexicalDeclContext(CurContext); 2176 2177 // Handle attributes prior to checking for duplicates in MergeVarDecl 2178 ProcessDeclAttributes(S, NewVD, D); 2179 2180 // Handle GNU asm-label extension (encoded as an attribute). 2181 if (Expr *E = (Expr*) D.getAsmLabel()) { 2182 // The parser guarantees this is a string. 2183 StringLiteral *SE = cast<StringLiteral>(E); 2184 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2185 SE->getByteLength()))); 2186 } 2187 2188 // If name lookup finds a previous declaration that is not in the 2189 // same scope as the new declaration, this may still be an 2190 // acceptable redeclaration. 2191 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2192 !(NewVD->hasLinkage() && 2193 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2194 PrevDecl = 0; 2195 2196 // Merge the decl with the existing one if appropriate. 2197 if (PrevDecl) { 2198 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2199 // The user tried to define a non-static data member 2200 // out-of-line (C++ [dcl.meaning]p1). 2201 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2202 << D.getCXXScopeSpec().getRange(); 2203 PrevDecl = 0; 2204 NewVD->setInvalidDecl(); 2205 } 2206 } else if (D.getCXXScopeSpec().isSet()) { 2207 // No previous declaration in the qualifying scope. 2208 NestedNameSpecifier *NNS = 2209 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2210 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2211 D.getCXXScopeSpec().getRange()); 2212 NewVD->setInvalidDecl(); 2213 } 2214 2215 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2216 2217 // attributes declared post-definition are currently ignored 2218 if (PrevDecl) { 2219 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2220 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2221 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2222 Diag(Def->getLocation(), diag::note_previous_definition); 2223 } 2224 } 2225 2226 // If this is a locally-scoped extern C variable, update the map of 2227 // such variables. 2228 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 2229 !NewVD->isInvalidDecl()) 2230 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2231 2232 return NewVD; 2233} 2234 2235/// \brief Perform semantic checking on a newly-created variable 2236/// declaration. 2237/// 2238/// This routine performs all of the type-checking required for a 2239/// variable declaration once it has been built. It is used both to 2240/// check variables after they have been parsed and their declarators 2241/// have been translated into a declaration, and to check variables 2242/// that have been instantiated from a template. 2243/// 2244/// Sets NewVD->isInvalidDecl() if an error was encountered. 2245void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2246 bool &Redeclaration) { 2247 // If the decl is already known invalid, don't check it. 2248 if (NewVD->isInvalidDecl()) 2249 return; 2250 2251 QualType T = NewVD->getType(); 2252 2253 if (T->isObjCInterfaceType()) { 2254 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2255 return NewVD->setInvalidDecl(); 2256 } 2257 2258 // The variable can not have an abstract class type. 2259 if (RequireNonAbstractType(NewVD->getLocation(), T, 2260 diag::err_abstract_type_in_decl, 2261 AbstractVariableType)) 2262 return NewVD->setInvalidDecl(); 2263 2264 // Emit an error if an address space was applied to decl with local storage. 2265 // This includes arrays of objects with address space qualifiers, but not 2266 // automatic variables that point to other address spaces. 2267 // ISO/IEC TR 18037 S5.1.2 2268 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2269 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2270 return NewVD->setInvalidDecl(); 2271 } 2272 2273 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2274 && !NewVD->hasAttr<BlocksAttr>()) 2275 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2276 2277 bool isVM = T->isVariablyModifiedType(); 2278 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2279 NewVD->hasAttr<BlocksAttr>()) 2280 CurFunctionNeedsScopeChecking = true; 2281 2282 if ((isVM && NewVD->hasLinkage()) || 2283 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2284 bool SizeIsNegative; 2285 QualType FixedTy = 2286 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2287 2288 if (FixedTy.isNull() && T->isVariableArrayType()) { 2289 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2290 // FIXME: This won't give the correct result for 2291 // int a[10][n]; 2292 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2293 2294 if (NewVD->isFileVarDecl()) 2295 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2296 << SizeRange; 2297 else if (NewVD->getStorageClass() == VarDecl::Static) 2298 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2299 << SizeRange; 2300 else 2301 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2302 << SizeRange; 2303 return NewVD->setInvalidDecl(); 2304 } 2305 2306 if (FixedTy.isNull()) { 2307 if (NewVD->isFileVarDecl()) 2308 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2309 else 2310 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2311 return NewVD->setInvalidDecl(); 2312 } 2313 2314 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2315 NewVD->setType(FixedTy); 2316 } 2317 2318 if (!PrevDecl && NewVD->isExternC(Context)) { 2319 // Since we did not find anything by this name and we're declaring 2320 // an extern "C" variable, look for a non-visible extern "C" 2321 // declaration with the same name. 2322 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2323 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2324 if (Pos != LocallyScopedExternalDecls.end()) 2325 PrevDecl = Pos->second; 2326 } 2327 2328 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2329 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2330 << T; 2331 return NewVD->setInvalidDecl(); 2332 } 2333 2334 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2335 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2336 return NewVD->setInvalidDecl(); 2337 } 2338 2339 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2340 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2341 return NewVD->setInvalidDecl(); 2342 } 2343 2344 if (PrevDecl) { 2345 Redeclaration = true; 2346 MergeVarDecl(NewVD, PrevDecl); 2347 } 2348} 2349 2350static bool isUsingDecl(Decl *D) { 2351 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2352} 2353 2354NamedDecl* 2355Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2356 QualType R, DeclaratorInfo *DInfo, 2357 NamedDecl* PrevDecl, 2358 MultiTemplateParamsArg TemplateParamLists, 2359 bool IsFunctionDefinition, bool &Redeclaration) { 2360 assert(R.getTypePtr()->isFunctionType()); 2361 2362 DeclarationName Name = GetNameForDeclarator(D); 2363 FunctionDecl::StorageClass SC = FunctionDecl::None; 2364 switch (D.getDeclSpec().getStorageClassSpec()) { 2365 default: assert(0 && "Unknown storage class!"); 2366 case DeclSpec::SCS_auto: 2367 case DeclSpec::SCS_register: 2368 case DeclSpec::SCS_mutable: 2369 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2370 diag::err_typecheck_sclass_func); 2371 D.setInvalidType(); 2372 break; 2373 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2374 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2375 case DeclSpec::SCS_static: { 2376 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2377 // C99 6.7.1p5: 2378 // The declaration of an identifier for a function that has 2379 // block scope shall have no explicit storage-class specifier 2380 // other than extern 2381 // See also (C++ [dcl.stc]p4). 2382 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2383 diag::err_static_block_func); 2384 SC = FunctionDecl::None; 2385 } else 2386 SC = FunctionDecl::Static; 2387 break; 2388 } 2389 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2390 } 2391 2392 if (D.getDeclSpec().isThreadSpecified()) 2393 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2394 2395 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2396 bool isInline = D.getDeclSpec().isInlineSpecified(); 2397 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2398 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2399 2400 // Check that the return type is not an abstract class type. 2401 // For record types, this is done by the AbstractClassUsageDiagnoser once 2402 // the class has been completely parsed. 2403 if (!DC->isRecord() && 2404 RequireNonAbstractType(D.getIdentifierLoc(), 2405 R->getAsFunctionType()->getResultType(), 2406 diag::err_abstract_type_in_decl, 2407 AbstractReturnType)) 2408 D.setInvalidType(); 2409 2410 // Do not allow returning a objc interface by-value. 2411 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2412 Diag(D.getIdentifierLoc(), 2413 diag::err_object_cannot_be_passed_returned_by_value) << 0 2414 << R->getAsFunctionType()->getResultType(); 2415 D.setInvalidType(); 2416 } 2417 2418 bool isVirtualOkay = false; 2419 FunctionDecl *NewFD; 2420 2421 if (isFriend) { 2422 // DC is the namespace in which the function is being declared. 2423 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2424 "friend function being created in a non-namespace context"); 2425 2426 // C++ [class.friend]p5 2427 // A function can be defined in a friend declaration of a 2428 // class . . . . Such a function is implicitly inline. 2429 isInline |= IsFunctionDefinition; 2430 } 2431 2432 if (D.getKind() == Declarator::DK_Constructor) { 2433 // This is a C++ constructor declaration. 2434 assert(DC->isRecord() && 2435 "Constructors can only be declared in a member context"); 2436 2437 R = CheckConstructorDeclarator(D, R, SC); 2438 2439 // Create the new declaration 2440 NewFD = CXXConstructorDecl::Create(Context, 2441 cast<CXXRecordDecl>(DC), 2442 D.getIdentifierLoc(), Name, R, DInfo, 2443 isExplicit, isInline, 2444 /*isImplicitlyDeclared=*/false); 2445 } else if (D.getKind() == Declarator::DK_Destructor) { 2446 // This is a C++ destructor declaration. 2447 if (DC->isRecord()) { 2448 R = CheckDestructorDeclarator(D, SC); 2449 2450 NewFD = CXXDestructorDecl::Create(Context, 2451 cast<CXXRecordDecl>(DC), 2452 D.getIdentifierLoc(), Name, R, 2453 isInline, 2454 /*isImplicitlyDeclared=*/false); 2455 2456 isVirtualOkay = true; 2457 } else { 2458 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2459 2460 // Create a FunctionDecl to satisfy the function definition parsing 2461 // code path. 2462 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2463 Name, R, DInfo, SC, isInline, 2464 /*hasPrototype=*/true); 2465 D.setInvalidType(); 2466 } 2467 } else if (D.getKind() == Declarator::DK_Conversion) { 2468 if (!DC->isRecord()) { 2469 Diag(D.getIdentifierLoc(), 2470 diag::err_conv_function_not_member); 2471 return 0; 2472 } 2473 2474 CheckConversionDeclarator(D, R, SC); 2475 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2476 D.getIdentifierLoc(), Name, R, DInfo, 2477 isInline, isExplicit); 2478 2479 isVirtualOkay = true; 2480 } else if (DC->isRecord()) { 2481 // If the of the function is the same as the name of the record, then this 2482 // must be an invalid constructor that has a return type. 2483 // (The parser checks for a return type and makes the declarator a 2484 // constructor if it has no return type). 2485 // must have an invalid constructor that has a return type 2486 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2487 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2488 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2489 << SourceRange(D.getIdentifierLoc()); 2490 return 0; 2491 } 2492 2493 // This is a C++ method declaration. 2494 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2495 D.getIdentifierLoc(), Name, R, DInfo, 2496 (SC == FunctionDecl::Static), isInline); 2497 2498 isVirtualOkay = (SC != FunctionDecl::Static); 2499 } else { 2500 // Determine whether the function was written with a 2501 // prototype. This true when: 2502 // - we're in C++ (where every function has a prototype), 2503 // - there is a prototype in the declarator, or 2504 // - the type R of the function is some kind of typedef or other reference 2505 // to a type name (which eventually refers to a function type). 2506 bool HasPrototype = 2507 getLangOptions().CPlusPlus || 2508 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2509 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2510 2511 NewFD = FunctionDecl::Create(Context, DC, 2512 D.getIdentifierLoc(), 2513 Name, R, DInfo, SC, isInline, HasPrototype); 2514 } 2515 2516 if (D.isInvalidType()) 2517 NewFD->setInvalidDecl(); 2518 2519 // Set the lexical context. If the declarator has a C++ 2520 // scope specifier, or is the object of a friend declaration, the 2521 // lexical context will be different from the semantic context. 2522 NewFD->setLexicalDeclContext(CurContext); 2523 2524 if (isFriend) 2525 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2526 2527 // Match up the template parameter lists with the scope specifier, then 2528 // determine whether we have a template or a template specialization. 2529 FunctionTemplateDecl *FunctionTemplate = 0; 2530 if (TemplateParameterList *TemplateParams 2531 = MatchTemplateParametersToScopeSpecifier( 2532 D.getDeclSpec().getSourceRange().getBegin(), 2533 D.getCXXScopeSpec(), 2534 (TemplateParameterList**)TemplateParamLists.get(), 2535 TemplateParamLists.size())) { 2536 if (TemplateParams->size() > 0) { 2537 // This is a function template 2538 2539 // Check that we can declare a template here. 2540 if (CheckTemplateDeclScope(S, TemplateParams)) 2541 return 0; 2542 2543 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2544 NewFD->getLocation(), 2545 Name, TemplateParams, 2546 NewFD); 2547 FunctionTemplate->setLexicalDeclContext(CurContext); 2548 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2549 } else { 2550 // FIXME: Handle function template specializations 2551 } 2552 2553 // FIXME: Free this memory properly. 2554 TemplateParamLists.release(); 2555 } 2556 2557 // C++ [dcl.fct.spec]p5: 2558 // The virtual specifier shall only be used in declarations of 2559 // nonstatic class member functions that appear within a 2560 // member-specification of a class declaration; see 10.3. 2561 // 2562 if (isVirtual && !NewFD->isInvalidDecl()) { 2563 if (!isVirtualOkay) { 2564 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2565 diag::err_virtual_non_function); 2566 } else if (!CurContext->isRecord()) { 2567 // 'virtual' was specified outside of the class. 2568 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2569 << CodeModificationHint::CreateRemoval( 2570 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2571 } else { 2572 // Okay: Add virtual to the method. 2573 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2574 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2575 CurClass->setAggregate(false); 2576 CurClass->setPOD(false); 2577 CurClass->setEmpty(false); 2578 CurClass->setPolymorphic(true); 2579 CurClass->setHasTrivialConstructor(false); 2580 CurClass->setHasTrivialCopyConstructor(false); 2581 CurClass->setHasTrivialCopyAssignment(false); 2582 } 2583 } 2584 2585 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2586 // Look for virtual methods in base classes that this method might override. 2587 2588 BasePaths Paths; 2589 if (LookupInBases(cast<CXXRecordDecl>(DC), 2590 MemberLookupCriteria(NewMD), Paths)) { 2591 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2592 E = Paths.found_decls_end(); I != E; ++I) { 2593 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2594 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2595 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2596 NewMD->addOverriddenMethod(OldMD); 2597 } 2598 } 2599 } 2600 } 2601 2602 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2603 !CurContext->isRecord()) { 2604 // C++ [class.static]p1: 2605 // A data or function member of a class may be declared static 2606 // in a class definition, in which case it is a static member of 2607 // the class. 2608 2609 // Complain about the 'static' specifier if it's on an out-of-line 2610 // member function definition. 2611 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2612 diag::err_static_out_of_line) 2613 << CodeModificationHint::CreateRemoval( 2614 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2615 } 2616 2617 // Handle GNU asm-label extension (encoded as an attribute). 2618 if (Expr *E = (Expr*) D.getAsmLabel()) { 2619 // The parser guarantees this is a string. 2620 StringLiteral *SE = cast<StringLiteral>(E); 2621 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2622 SE->getByteLength()))); 2623 } 2624 2625 // Copy the parameter declarations from the declarator D to the function 2626 // declaration NewFD, if they are available. First scavenge them into Params. 2627 llvm::SmallVector<ParmVarDecl*, 16> Params; 2628 if (D.getNumTypeObjects() > 0) { 2629 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2630 2631 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2632 // function that takes no arguments, not a function that takes a 2633 // single void argument. 2634 // We let through "const void" here because Sema::GetTypeForDeclarator 2635 // already checks for that case. 2636 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2637 FTI.ArgInfo[0].Param && 2638 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2639 // Empty arg list, don't push any params. 2640 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2641 2642 // In C++, the empty parameter-type-list must be spelled "void"; a 2643 // typedef of void is not permitted. 2644 if (getLangOptions().CPlusPlus && 2645 Param->getType().getUnqualifiedType() != Context.VoidTy) 2646 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2647 // FIXME: Leaks decl? 2648 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2649 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2650 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2651 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2652 Param->setDeclContext(NewFD); 2653 Params.push_back(Param); 2654 } 2655 } 2656 2657 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2658 // When we're declaring a function with a typedef, typeof, etc as in the 2659 // following example, we'll need to synthesize (unnamed) 2660 // parameters for use in the declaration. 2661 // 2662 // @code 2663 // typedef void fn(int); 2664 // fn f; 2665 // @endcode 2666 2667 // Synthesize a parameter for each argument type. 2668 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2669 AE = FT->arg_type_end(); AI != AE; ++AI) { 2670 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2671 SourceLocation(), 0, 2672 *AI, /*DInfo=*/0, 2673 VarDecl::None, 0); 2674 Param->setImplicit(); 2675 Params.push_back(Param); 2676 } 2677 } else { 2678 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2679 "Should not need args for typedef of non-prototype fn"); 2680 } 2681 // Finally, we know we have the right number of parameters, install them. 2682 NewFD->setParams(Context, Params.data(), Params.size()); 2683 2684 // If name lookup finds a previous declaration that is not in the 2685 // same scope as the new declaration, this may still be an 2686 // acceptable redeclaration. 2687 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2688 !(NewFD->hasLinkage() && 2689 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2690 PrevDecl = 0; 2691 2692 // Perform semantic checking on the function declaration. 2693 bool OverloadableAttrRequired = false; // FIXME: HACK! 2694 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2695 /*FIXME:*/OverloadableAttrRequired); 2696 2697 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2698 // An out-of-line member function declaration must also be a 2699 // definition (C++ [dcl.meaning]p1). 2700 if (!IsFunctionDefinition && !isFriend) { 2701 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2702 << D.getCXXScopeSpec().getRange(); 2703 NewFD->setInvalidDecl(); 2704 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2705 // The user tried to provide an out-of-line definition for a 2706 // function that is a member of a class or namespace, but there 2707 // was no such member function declared (C++ [class.mfct]p2, 2708 // C++ [namespace.memdef]p2). For example: 2709 // 2710 // class X { 2711 // void f() const; 2712 // }; 2713 // 2714 // void X::f() { } // ill-formed 2715 // 2716 // Complain about this problem, and attempt to suggest close 2717 // matches (e.g., those that differ only in cv-qualifiers and 2718 // whether the parameter types are references). 2719 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2720 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2721 NewFD->setInvalidDecl(); 2722 2723 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2724 true); 2725 assert(!Prev.isAmbiguous() && 2726 "Cannot have an ambiguity in previous-declaration lookup"); 2727 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2728 Func != FuncEnd; ++Func) { 2729 if (isa<FunctionDecl>(*Func) && 2730 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2731 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2732 } 2733 2734 PrevDecl = 0; 2735 } 2736 } 2737 2738 // Handle attributes. We need to have merged decls when handling attributes 2739 // (for example to check for conflicts, etc). 2740 // FIXME: This needs to happen before we merge declarations. Then, 2741 // let attribute merging cope with attribute conflicts. 2742 ProcessDeclAttributes(S, NewFD, D); 2743 2744 // attributes declared post-definition are currently ignored 2745 if (Redeclaration && PrevDecl) { 2746 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2747 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2748 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2749 Diag(Def->getLocation(), diag::note_previous_definition); 2750 } 2751 } 2752 2753 AddKnownFunctionAttributes(NewFD); 2754 2755 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2756 // If a function name is overloadable in C, then every function 2757 // with that name must be marked "overloadable". 2758 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2759 << Redeclaration << NewFD; 2760 if (PrevDecl) 2761 Diag(PrevDecl->getLocation(), 2762 diag::note_attribute_overloadable_prev_overload); 2763 NewFD->addAttr(::new (Context) OverloadableAttr()); 2764 } 2765 2766 // If this is a locally-scoped extern C function, update the 2767 // map of such names. 2768 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2769 && !NewFD->isInvalidDecl()) 2770 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2771 2772 // Set this FunctionDecl's range up to the right paren. 2773 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2774 2775 if (FunctionTemplate && NewFD->isInvalidDecl()) 2776 FunctionTemplate->setInvalidDecl(); 2777 2778 if (FunctionTemplate) 2779 return FunctionTemplate; 2780 2781 return NewFD; 2782} 2783 2784/// \brief Perform semantic checking of a new function declaration. 2785/// 2786/// Performs semantic analysis of the new function declaration 2787/// NewFD. This routine performs all semantic checking that does not 2788/// require the actual declarator involved in the declaration, and is 2789/// used both for the declaration of functions as they are parsed 2790/// (called via ActOnDeclarator) and for the declaration of functions 2791/// that have been instantiated via C++ template instantiation (called 2792/// via InstantiateDecl). 2793/// 2794/// This sets NewFD->isInvalidDecl() to true if there was an error. 2795void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2796 bool &Redeclaration, 2797 bool &OverloadableAttrRequired) { 2798 // If NewFD is already known erroneous, don't do any of this checking. 2799 if (NewFD->isInvalidDecl()) 2800 return; 2801 2802 if (NewFD->getResultType()->isVariablyModifiedType()) { 2803 // Functions returning a variably modified type violate C99 6.7.5.2p2 2804 // because all functions have linkage. 2805 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2806 return NewFD->setInvalidDecl(); 2807 } 2808 2809 if (NewFD->isMain(Context)) CheckMain(NewFD); 2810 2811 // Semantic checking for this function declaration (in isolation). 2812 if (getLangOptions().CPlusPlus) { 2813 // C++-specific checks. 2814 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2815 CheckConstructor(Constructor); 2816 } else if (isa<CXXDestructorDecl>(NewFD)) { 2817 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2818 QualType ClassType = Context.getTypeDeclType(Record); 2819 if (!ClassType->isDependentType()) { 2820 DeclarationName Name 2821 = Context.DeclarationNames.getCXXDestructorName( 2822 Context.getCanonicalType(ClassType)); 2823 if (NewFD->getDeclName() != Name) { 2824 Diag(NewFD->getLocation(), diag::err_destructor_name); 2825 return NewFD->setInvalidDecl(); 2826 } 2827 } 2828 Record->setUserDeclaredDestructor(true); 2829 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2830 // user-defined destructor. 2831 Record->setPOD(false); 2832 2833 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2834 // declared destructor. 2835 // FIXME: C++0x: don't do this for "= default" destructors 2836 Record->setHasTrivialDestructor(false); 2837 } else if (CXXConversionDecl *Conversion 2838 = dyn_cast<CXXConversionDecl>(NewFD)) 2839 ActOnConversionDeclarator(Conversion); 2840 2841 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2842 if (NewFD->isOverloadedOperator() && 2843 CheckOverloadedOperatorDeclaration(NewFD)) 2844 return NewFD->setInvalidDecl(); 2845 } 2846 2847 // C99 6.7.4p6: 2848 // [... ] For a function with external linkage, the following 2849 // restrictions apply: [...] If all of the file scope declarations 2850 // for a function in a translation unit include the inline 2851 // function specifier without extern, then the definition in that 2852 // translation unit is an inline definition. An inline definition 2853 // does not provide an external definition for the function, and 2854 // does not forbid an external definition in another translation 2855 // unit. 2856 // 2857 // Here we determine whether this function, in isolation, would be a 2858 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2859 // previous declarations. 2860 if (NewFD->isInline() && getLangOptions().C99 && 2861 NewFD->getStorageClass() == FunctionDecl::None && 2862 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2863 NewFD->setC99InlineDefinition(true); 2864 2865 // Check for a previous declaration of this name. 2866 if (!PrevDecl && NewFD->isExternC(Context)) { 2867 // Since we did not find anything by this name and we're declaring 2868 // an extern "C" function, look for a non-visible extern "C" 2869 // declaration with the same name. 2870 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2871 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2872 if (Pos != LocallyScopedExternalDecls.end()) 2873 PrevDecl = Pos->second; 2874 } 2875 2876 // Merge or overload the declaration with an existing declaration of 2877 // the same name, if appropriate. 2878 if (PrevDecl) { 2879 // Determine whether NewFD is an overload of PrevDecl or 2880 // a declaration that requires merging. If it's an overload, 2881 // there's no more work to do here; we'll just add the new 2882 // function to the scope. 2883 OverloadedFunctionDecl::function_iterator MatchedDecl; 2884 2885 if (!getLangOptions().CPlusPlus && 2886 AllowOverloadingOfFunction(PrevDecl, Context)) { 2887 OverloadableAttrRequired = true; 2888 2889 // Functions marked "overloadable" must have a prototype (that 2890 // we can't get through declaration merging). 2891 if (!NewFD->getType()->getAsFunctionProtoType()) { 2892 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2893 << NewFD; 2894 Redeclaration = true; 2895 2896 // Turn this into a variadic function with no parameters. 2897 QualType R = Context.getFunctionType( 2898 NewFD->getType()->getAsFunctionType()->getResultType(), 2899 0, 0, true, 0); 2900 NewFD->setType(R); 2901 return NewFD->setInvalidDecl(); 2902 } 2903 } 2904 2905 if (PrevDecl && 2906 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2907 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2908 Redeclaration = true; 2909 Decl *OldDecl = PrevDecl; 2910 2911 // If PrevDecl was an overloaded function, extract the 2912 // FunctionDecl that matched. 2913 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2914 OldDecl = *MatchedDecl; 2915 2916 // NewFD and OldDecl represent declarations that need to be 2917 // merged. 2918 if (MergeFunctionDecl(NewFD, OldDecl)) 2919 return NewFD->setInvalidDecl(); 2920 2921 if (FunctionTemplateDecl *OldTemplateDecl 2922 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2923 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2924 else { 2925 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2926 NewFD->setAccess(OldDecl->getAccess()); 2927 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2928 } 2929 } 2930 } 2931 2932 // In C++, check default arguments now that we have merged decls. Unless 2933 // the lexical context is the class, because in this case this is done 2934 // during delayed parsing anyway. 2935 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2936 CheckCXXDefaultArguments(NewFD); 2937} 2938 2939void Sema::CheckMain(FunctionDecl* FD) { 2940 // C++ [basic.start.main]p3: A program that declares main to be inline 2941 // or static is ill-formed. 2942 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2943 // shall not appear in a declaration of main. 2944 // static main is not an error under C99, but we should warn about it. 2945 bool isInline = FD->isInline(); 2946 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2947 if (isInline || isStatic) { 2948 unsigned diagID = diag::warn_unusual_main_decl; 2949 if (isInline || getLangOptions().CPlusPlus) 2950 diagID = diag::err_unusual_main_decl; 2951 2952 int which = isStatic + (isInline << 1) - 1; 2953 Diag(FD->getLocation(), diagID) << which; 2954 } 2955 2956 QualType T = FD->getType(); 2957 assert(T->isFunctionType() && "function decl is not of function type"); 2958 const FunctionType* FT = T->getAsFunctionType(); 2959 2960 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2961 // TODO: add a replacement fixit to turn the return type into 'int'. 2962 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2963 FD->setInvalidDecl(true); 2964 } 2965 2966 // Treat protoless main() as nullary. 2967 if (isa<FunctionNoProtoType>(FT)) return; 2968 2969 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2970 unsigned nparams = FTP->getNumArgs(); 2971 assert(FD->getNumParams() == nparams); 2972 2973 if (nparams > 3) { 2974 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2975 FD->setInvalidDecl(true); 2976 nparams = 3; 2977 } 2978 2979 // FIXME: a lot of the following diagnostics would be improved 2980 // if we had some location information about types. 2981 2982 QualType CharPP = 2983 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2984 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2985 2986 for (unsigned i = 0; i < nparams; ++i) { 2987 QualType AT = FTP->getArgType(i); 2988 2989 bool mismatch = true; 2990 2991 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2992 mismatch = false; 2993 else if (Expected[i] == CharPP) { 2994 // As an extension, the following forms are okay: 2995 // char const ** 2996 // char const * const * 2997 // char * const * 2998 2999 QualifierSet qs; 3000 const PointerType* PT; 3001 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3002 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3003 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3004 qs.removeConst(); 3005 mismatch = !qs.empty(); 3006 } 3007 } 3008 3009 if (mismatch) { 3010 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3011 // TODO: suggest replacing given type with expected type 3012 FD->setInvalidDecl(true); 3013 } 3014 } 3015 3016 if (nparams == 1 && !FD->isInvalidDecl()) { 3017 Diag(FD->getLocation(), diag::warn_main_one_arg); 3018 } 3019} 3020 3021bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3022 // FIXME: Need strict checking. In C89, we need to check for 3023 // any assignment, increment, decrement, function-calls, or 3024 // commas outside of a sizeof. In C99, it's the same list, 3025 // except that the aforementioned are allowed in unevaluated 3026 // expressions. Everything else falls under the 3027 // "may accept other forms of constant expressions" exception. 3028 // (We never end up here for C++, so the constant expression 3029 // rules there don't matter.) 3030 if (Init->isConstantInitializer(Context)) 3031 return false; 3032 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3033 << Init->getSourceRange(); 3034 return true; 3035} 3036 3037void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3038 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3039} 3040 3041/// AddInitializerToDecl - Adds the initializer Init to the 3042/// declaration dcl. If DirectInit is true, this is C++ direct 3043/// initialization rather than copy initialization. 3044void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3045 Decl *RealDecl = dcl.getAs<Decl>(); 3046 // If there is no declaration, there was an error parsing it. Just ignore 3047 // the initializer. 3048 if (RealDecl == 0) 3049 return; 3050 3051 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3052 // With declarators parsed the way they are, the parser cannot 3053 // distinguish between a normal initializer and a pure-specifier. 3054 // Thus this grotesque test. 3055 IntegerLiteral *IL; 3056 Expr *Init = static_cast<Expr *>(init.get()); 3057 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3058 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3059 if (Method->isVirtualAsWritten()) { 3060 Method->setPure(); 3061 3062 // A class is abstract if at least one function is pure virtual. 3063 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3064 } else if (!Method->isInvalidDecl()) { 3065 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3066 << Method->getDeclName() << Init->getSourceRange(); 3067 Method->setInvalidDecl(); 3068 } 3069 } else { 3070 Diag(Method->getLocation(), diag::err_member_function_initialization) 3071 << Method->getDeclName() << Init->getSourceRange(); 3072 Method->setInvalidDecl(); 3073 } 3074 return; 3075 } 3076 3077 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3078 if (!VDecl) { 3079 if (getLangOptions().CPlusPlus && 3080 RealDecl->getLexicalDeclContext()->isRecord() && 3081 isa<NamedDecl>(RealDecl)) 3082 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3083 << cast<NamedDecl>(RealDecl)->getDeclName(); 3084 else 3085 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3086 RealDecl->setInvalidDecl(); 3087 return; 3088 } 3089 3090 if (!VDecl->getType()->isArrayType() && 3091 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3092 diag::err_typecheck_decl_incomplete_type)) { 3093 RealDecl->setInvalidDecl(); 3094 return; 3095 } 3096 3097 const VarDecl *Def = 0; 3098 if (VDecl->getDefinition(Def)) { 3099 Diag(VDecl->getLocation(), diag::err_redefinition) 3100 << VDecl->getDeclName(); 3101 Diag(Def->getLocation(), diag::note_previous_definition); 3102 VDecl->setInvalidDecl(); 3103 return; 3104 } 3105 3106 // Take ownership of the expression, now that we're sure we have somewhere 3107 // to put it. 3108 Expr *Init = init.takeAs<Expr>(); 3109 assert(Init && "missing initializer"); 3110 3111 // Get the decls type and save a reference for later, since 3112 // CheckInitializerTypes may change it. 3113 QualType DclT = VDecl->getType(), SavT = DclT; 3114 if (VDecl->isBlockVarDecl()) { 3115 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3116 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3117 VDecl->setInvalidDecl(); 3118 } else if (!VDecl->isInvalidDecl()) { 3119 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3120 VDecl->getDeclName(), DirectInit)) 3121 VDecl->setInvalidDecl(); 3122 3123 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3124 // Don't check invalid declarations to avoid emitting useless diagnostics. 3125 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3126 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3127 CheckForConstantInitializer(Init, DclT); 3128 } 3129 } 3130 } else if (VDecl->isStaticDataMember() && 3131 VDecl->getLexicalDeclContext()->isRecord()) { 3132 // This is an in-class initialization for a static data member, e.g., 3133 // 3134 // struct S { 3135 // static const int value = 17; 3136 // }; 3137 3138 // Attach the initializer 3139 VDecl->setInit(Context, Init); 3140 3141 // C++ [class.mem]p4: 3142 // A member-declarator can contain a constant-initializer only 3143 // if it declares a static member (9.4) of const integral or 3144 // const enumeration type, see 9.4.2. 3145 QualType T = VDecl->getType(); 3146 if (!T->isDependentType() && 3147 (!Context.getCanonicalType(T).isConstQualified() || 3148 !T->isIntegralType())) { 3149 Diag(VDecl->getLocation(), diag::err_member_initialization) 3150 << VDecl->getDeclName() << Init->getSourceRange(); 3151 VDecl->setInvalidDecl(); 3152 } else { 3153 // C++ [class.static.data]p4: 3154 // If a static data member is of const integral or const 3155 // enumeration type, its declaration in the class definition 3156 // can specify a constant-initializer which shall be an 3157 // integral constant expression (5.19). 3158 if (!Init->isTypeDependent() && 3159 !Init->getType()->isIntegralType()) { 3160 // We have a non-dependent, non-integral or enumeration type. 3161 Diag(Init->getSourceRange().getBegin(), 3162 diag::err_in_class_initializer_non_integral_type) 3163 << Init->getType() << Init->getSourceRange(); 3164 VDecl->setInvalidDecl(); 3165 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3166 // Check whether the expression is a constant expression. 3167 llvm::APSInt Value; 3168 SourceLocation Loc; 3169 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3170 Diag(Loc, diag::err_in_class_initializer_non_constant) 3171 << Init->getSourceRange(); 3172 VDecl->setInvalidDecl(); 3173 } else if (!VDecl->getType()->isDependentType()) 3174 ImpCastExprToType(Init, VDecl->getType()); 3175 } 3176 } 3177 } else if (VDecl->isFileVarDecl()) { 3178 if (VDecl->getStorageClass() == VarDecl::Extern) 3179 Diag(VDecl->getLocation(), diag::warn_extern_init); 3180 if (!VDecl->isInvalidDecl()) 3181 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3182 VDecl->getDeclName(), DirectInit)) 3183 VDecl->setInvalidDecl(); 3184 3185 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3186 // Don't check invalid declarations to avoid emitting useless diagnostics. 3187 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3188 // C99 6.7.8p4. All file scoped initializers need to be constant. 3189 CheckForConstantInitializer(Init, DclT); 3190 } 3191 } 3192 // If the type changed, it means we had an incomplete type that was 3193 // completed by the initializer. For example: 3194 // int ary[] = { 1, 3, 5 }; 3195 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3196 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3197 VDecl->setType(DclT); 3198 Init->setType(DclT); 3199 } 3200 3201 Init = MaybeCreateCXXExprWithTemporaries(Init, 3202 /*ShouldDestroyTemporaries=*/true); 3203 // Attach the initializer to the decl. 3204 VDecl->setInit(Context, Init); 3205 3206 // If the previous declaration of VDecl was a tentative definition, 3207 // remove it from the set of tentative definitions. 3208 if (VDecl->getPreviousDeclaration() && 3209 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3210 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 3211 = TentativeDefinitions.find(VDecl->getDeclName()); 3212 assert(Pos != TentativeDefinitions.end() && 3213 "Unrecorded tentative definition?"); 3214 TentativeDefinitions.erase(Pos); 3215 } 3216 3217 return; 3218} 3219 3220void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3221 bool TypeContainsUndeducedAuto) { 3222 Decl *RealDecl = dcl.getAs<Decl>(); 3223 3224 // If there is no declaration, there was an error parsing it. Just ignore it. 3225 if (RealDecl == 0) 3226 return; 3227 3228 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3229 QualType Type = Var->getType(); 3230 3231 // Record tentative definitions. 3232 if (Var->isTentativeDefinition(Context)) 3233 TentativeDefinitions[Var->getDeclName()] = Var; 3234 3235 // C++ [dcl.init.ref]p3: 3236 // The initializer can be omitted for a reference only in a 3237 // parameter declaration (8.3.5), in the declaration of a 3238 // function return type, in the declaration of a class member 3239 // within its class declaration (9.2), and where the extern 3240 // specifier is explicitly used. 3241 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3242 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3243 << Var->getDeclName() 3244 << SourceRange(Var->getLocation(), Var->getLocation()); 3245 Var->setInvalidDecl(); 3246 return; 3247 } 3248 3249 // C++0x [dcl.spec.auto]p3 3250 if (TypeContainsUndeducedAuto) { 3251 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3252 << Var->getDeclName() << Type; 3253 Var->setInvalidDecl(); 3254 return; 3255 } 3256 3257 // C++ [dcl.init]p9: 3258 // 3259 // If no initializer is specified for an object, and the object 3260 // is of (possibly cv-qualified) non-POD class type (or array 3261 // thereof), the object shall be default-initialized; if the 3262 // object is of const-qualified type, the underlying class type 3263 // shall have a user-declared default constructor. 3264 if (getLangOptions().CPlusPlus) { 3265 QualType InitType = Type; 3266 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3267 InitType = Array->getElementType(); 3268 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 3269 InitType->isRecordType() && !InitType->isDependentType()) { 3270 CXXRecordDecl *RD = 3271 cast<CXXRecordDecl>(InitType->getAs<RecordType>()->getDecl()); 3272 CXXConstructorDecl *Constructor = 0; 3273 if (!RequireCompleteType(Var->getLocation(), InitType, 3274 diag::err_invalid_incomplete_type_use)) 3275 Constructor 3276 = PerformInitializationByConstructor(InitType, 0, 0, 3277 Var->getLocation(), 3278 SourceRange(Var->getLocation(), 3279 Var->getLocation()), 3280 Var->getDeclName(), 3281 IK_Default); 3282 if (!Constructor) 3283 Var->setInvalidDecl(); 3284 else { 3285 if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()) { 3286 if (InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0)) 3287 Var->setInvalidDecl(); 3288 } 3289 3290 FinalizeVarWithDestructor(Var, InitType); 3291 } 3292 } 3293 } 3294 3295#if 0 3296 // FIXME: Temporarily disabled because we are not properly parsing 3297 // linkage specifications on declarations, e.g., 3298 // 3299 // extern "C" const CGPoint CGPointerZero; 3300 // 3301 // C++ [dcl.init]p9: 3302 // 3303 // If no initializer is specified for an object, and the 3304 // object is of (possibly cv-qualified) non-POD class type (or 3305 // array thereof), the object shall be default-initialized; if 3306 // the object is of const-qualified type, the underlying class 3307 // type shall have a user-declared default 3308 // constructor. Otherwise, if no initializer is specified for 3309 // an object, the object and its subobjects, if any, have an 3310 // indeterminate initial value; if the object or any of its 3311 // subobjects are of const-qualified type, the program is 3312 // ill-formed. 3313 // 3314 // This isn't technically an error in C, so we don't diagnose it. 3315 // 3316 // FIXME: Actually perform the POD/user-defined default 3317 // constructor check. 3318 if (getLangOptions().CPlusPlus && 3319 Context.getCanonicalType(Type).isConstQualified() && 3320 !Var->hasExternalStorage()) 3321 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3322 << Var->getName() 3323 << SourceRange(Var->getLocation(), Var->getLocation()); 3324#endif 3325 } 3326} 3327 3328Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3329 DeclPtrTy *Group, 3330 unsigned NumDecls) { 3331 llvm::SmallVector<Decl*, 8> Decls; 3332 3333 if (DS.isTypeSpecOwned()) 3334 Decls.push_back((Decl*)DS.getTypeRep()); 3335 3336 for (unsigned i = 0; i != NumDecls; ++i) 3337 if (Decl *D = Group[i].getAs<Decl>()) 3338 Decls.push_back(D); 3339 3340 // Perform semantic analysis that depends on having fully processed both 3341 // the declarator and initializer. 3342 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3343 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3344 if (!IDecl) 3345 continue; 3346 QualType T = IDecl->getType(); 3347 3348 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3349 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3350 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3351 if (!IDecl->isInvalidDecl() && 3352 RequireCompleteType(IDecl->getLocation(), T, 3353 diag::err_typecheck_decl_incomplete_type)) 3354 IDecl->setInvalidDecl(); 3355 } 3356 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3357 // object that has file scope without an initializer, and without a 3358 // storage-class specifier or with the storage-class specifier "static", 3359 // constitutes a tentative definition. Note: A tentative definition with 3360 // external linkage is valid (C99 6.2.2p5). 3361 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3362 if (const IncompleteArrayType *ArrayT 3363 = Context.getAsIncompleteArrayType(T)) { 3364 if (RequireCompleteType(IDecl->getLocation(), 3365 ArrayT->getElementType(), 3366 diag::err_illegal_decl_array_incomplete_type)) 3367 IDecl->setInvalidDecl(); 3368 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3369 // C99 6.9.2p3: If the declaration of an identifier for an object is 3370 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3371 // declared type shall not be an incomplete type. 3372 // NOTE: code such as the following 3373 // static struct s; 3374 // struct s { int a; }; 3375 // is accepted by gcc. Hence here we issue a warning instead of 3376 // an error and we do not invalidate the static declaration. 3377 // NOTE: to avoid multiple warnings, only check the first declaration. 3378 if (IDecl->getPreviousDeclaration() == 0) 3379 RequireCompleteType(IDecl->getLocation(), T, 3380 diag::ext_typecheck_decl_incomplete_type); 3381 } 3382 } 3383 } 3384 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3385 Decls.data(), Decls.size())); 3386} 3387 3388 3389/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3390/// to introduce parameters into function prototype scope. 3391Sema::DeclPtrTy 3392Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3393 const DeclSpec &DS = D.getDeclSpec(); 3394 3395 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3396 VarDecl::StorageClass StorageClass = VarDecl::None; 3397 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3398 StorageClass = VarDecl::Register; 3399 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3400 Diag(DS.getStorageClassSpecLoc(), 3401 diag::err_invalid_storage_class_in_func_decl); 3402 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3403 } 3404 3405 if (D.getDeclSpec().isThreadSpecified()) 3406 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3407 3408 DiagnoseFunctionSpecifiers(D); 3409 3410 // Check that there are no default arguments inside the type of this 3411 // parameter (C++ only). 3412 if (getLangOptions().CPlusPlus) 3413 CheckExtraCXXDefaultArguments(D); 3414 3415 DeclaratorInfo *DInfo = 0; 3416 TagDecl *OwnedDecl = 0; 3417 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3418 &OwnedDecl); 3419 3420 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3421 // C++ [dcl.fct]p6: 3422 // Types shall not be defined in return or parameter types. 3423 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3424 << Context.getTypeDeclType(OwnedDecl); 3425 } 3426 3427 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3428 // Can this happen for params? We already checked that they don't conflict 3429 // among each other. Here they can only shadow globals, which is ok. 3430 IdentifierInfo *II = D.getIdentifier(); 3431 if (II) { 3432 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3433 if (PrevDecl->isTemplateParameter()) { 3434 // Maybe we will complain about the shadowed template parameter. 3435 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3436 // Just pretend that we didn't see the previous declaration. 3437 PrevDecl = 0; 3438 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3439 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3440 3441 // Recover by removing the name 3442 II = 0; 3443 D.SetIdentifier(0, D.getIdentifierLoc()); 3444 } 3445 } 3446 } 3447 3448 // Parameters can not be abstract class types. 3449 // For record types, this is done by the AbstractClassUsageDiagnoser once 3450 // the class has been completely parsed. 3451 if (!CurContext->isRecord() && 3452 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3453 diag::err_abstract_type_in_decl, 3454 AbstractParamType)) 3455 D.setInvalidType(true); 3456 3457 QualType T = adjustParameterType(parmDeclType); 3458 3459 ParmVarDecl *New; 3460 if (T == parmDeclType) // parameter type did not need adjustment 3461 New = ParmVarDecl::Create(Context, CurContext, 3462 D.getIdentifierLoc(), II, 3463 parmDeclType, DInfo, StorageClass, 3464 0); 3465 else // keep track of both the adjusted and unadjusted types 3466 New = OriginalParmVarDecl::Create(Context, CurContext, 3467 D.getIdentifierLoc(), II, T, DInfo, 3468 parmDeclType, StorageClass, 0); 3469 3470 if (D.isInvalidType()) 3471 New->setInvalidDecl(); 3472 3473 // Parameter declarators cannot be interface types. All ObjC objects are 3474 // passed by reference. 3475 if (T->isObjCInterfaceType()) { 3476 Diag(D.getIdentifierLoc(), 3477 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3478 New->setInvalidDecl(); 3479 } 3480 3481 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3482 if (D.getCXXScopeSpec().isSet()) { 3483 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3484 << D.getCXXScopeSpec().getRange(); 3485 New->setInvalidDecl(); 3486 } 3487 3488 // Add the parameter declaration into this scope. 3489 S->AddDecl(DeclPtrTy::make(New)); 3490 if (II) 3491 IdResolver.AddDecl(New); 3492 3493 ProcessDeclAttributes(S, New, D); 3494 3495 if (New->hasAttr<BlocksAttr>()) { 3496 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3497 } 3498 return DeclPtrTy::make(New); 3499} 3500 3501void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3502 SourceLocation LocAfterDecls) { 3503 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3504 "Not a function declarator!"); 3505 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3506 3507 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3508 // for a K&R function. 3509 if (!FTI.hasPrototype) { 3510 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3511 --i; 3512 if (FTI.ArgInfo[i].Param == 0) { 3513 std::string Code = " int "; 3514 Code += FTI.ArgInfo[i].Ident->getName(); 3515 Code += ";\n"; 3516 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3517 << FTI.ArgInfo[i].Ident 3518 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3519 3520 // Implicitly declare the argument as type 'int' for lack of a better 3521 // type. 3522 DeclSpec DS; 3523 const char* PrevSpec; // unused 3524 unsigned DiagID; // unused 3525 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3526 PrevSpec, DiagID); 3527 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3528 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3529 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3530 } 3531 } 3532 } 3533} 3534 3535Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3536 Declarator &D) { 3537 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3538 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3539 "Not a function declarator!"); 3540 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3541 3542 if (FTI.hasPrototype) { 3543 // FIXME: Diagnose arguments without names in C. 3544 } 3545 3546 Scope *ParentScope = FnBodyScope->getParent(); 3547 3548 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3549 MultiTemplateParamsArg(*this), 3550 /*IsFunctionDefinition=*/true); 3551 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3552} 3553 3554Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3555 if (!D) 3556 return D; 3557 FunctionDecl *FD = 0; 3558 3559 if (FunctionTemplateDecl *FunTmpl 3560 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3561 FD = FunTmpl->getTemplatedDecl(); 3562 else 3563 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3564 3565 CurFunctionNeedsScopeChecking = false; 3566 3567 // See if this is a redefinition. 3568 const FunctionDecl *Definition; 3569 if (FD->getBody(Definition)) { 3570 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3571 Diag(Definition->getLocation(), diag::note_previous_definition); 3572 } 3573 3574 // Builtin functions cannot be defined. 3575 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3576 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3577 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3578 FD->setInvalidDecl(); 3579 } 3580 } 3581 3582 // The return type of a function definition must be complete 3583 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3584 QualType ResultType = FD->getResultType(); 3585 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3586 !FD->isInvalidDecl() && 3587 RequireCompleteType(FD->getLocation(), ResultType, 3588 diag::err_func_def_incomplete_result)) 3589 FD->setInvalidDecl(); 3590 3591 // GNU warning -Wmissing-prototypes: 3592 // Warn if a global function is defined without a previous 3593 // prototype declaration. This warning is issued even if the 3594 // definition itself provides a prototype. The aim is to detect 3595 // global functions that fail to be declared in header files. 3596 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3597 !FD->isMain(Context)) { 3598 bool MissingPrototype = true; 3599 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3600 Prev; Prev = Prev->getPreviousDeclaration()) { 3601 // Ignore any declarations that occur in function or method 3602 // scope, because they aren't visible from the header. 3603 if (Prev->getDeclContext()->isFunctionOrMethod()) 3604 continue; 3605 3606 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3607 break; 3608 } 3609 3610 if (MissingPrototype) 3611 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3612 } 3613 3614 if (FnBodyScope) 3615 PushDeclContext(FnBodyScope, FD); 3616 3617 // Check the validity of our function parameters 3618 CheckParmsForFunctionDef(FD); 3619 3620 // Introduce our parameters into the function scope 3621 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3622 ParmVarDecl *Param = FD->getParamDecl(p); 3623 Param->setOwningFunction(FD); 3624 3625 // If this has an identifier, add it to the scope stack. 3626 if (Param->getIdentifier() && FnBodyScope) 3627 PushOnScopeChains(Param, FnBodyScope); 3628 } 3629 3630 // Checking attributes of current function definition 3631 // dllimport attribute. 3632 if (FD->getAttr<DLLImportAttr>() && 3633 (!FD->getAttr<DLLExportAttr>())) { 3634 // dllimport attribute cannot be applied to definition. 3635 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3636 Diag(FD->getLocation(), 3637 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3638 << "dllimport"; 3639 FD->setInvalidDecl(); 3640 return DeclPtrTy::make(FD); 3641 } else { 3642 // If a symbol previously declared dllimport is later defined, the 3643 // attribute is ignored in subsequent references, and a warning is 3644 // emitted. 3645 Diag(FD->getLocation(), 3646 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3647 << FD->getNameAsCString() << "dllimport"; 3648 } 3649 } 3650 return DeclPtrTy::make(FD); 3651} 3652 3653Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3654 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3655} 3656 3657Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3658 bool IsInstantiation) { 3659 Decl *dcl = D.getAs<Decl>(); 3660 Stmt *Body = BodyArg.takeAs<Stmt>(); 3661 3662 FunctionDecl *FD = 0; 3663 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3664 if (FunTmpl) 3665 FD = FunTmpl->getTemplatedDecl(); 3666 else 3667 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3668 3669 if (FD) { 3670 FD->setBody(Body); 3671 if (FD->isMain(Context)) 3672 // C and C++ allow for main to automagically return 0. 3673 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3674 FD->setHasImplicitReturnZero(true); 3675 else 3676 CheckFallThroughForFunctionDef(FD, Body); 3677 3678 if (!FD->isInvalidDecl()) 3679 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3680 3681 // C++ [basic.def.odr]p2: 3682 // [...] A virtual member function is used if it is not pure. [...] 3683 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3684 if (Method->isVirtual() && !Method->isPure()) 3685 MarkDeclarationReferenced(Method->getLocation(), Method); 3686 3687 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3688 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3689 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3690 MD->setBody(Body); 3691 CheckFallThroughForFunctionDef(MD, Body); 3692 MD->setEndLoc(Body->getLocEnd()); 3693 3694 if (!MD->isInvalidDecl()) 3695 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3696 } else { 3697 Body->Destroy(Context); 3698 return DeclPtrTy(); 3699 } 3700 if (!IsInstantiation) 3701 PopDeclContext(); 3702 3703 // Verify and clean out per-function state. 3704 3705 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3706 3707 // Check goto/label use. 3708 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3709 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3710 LabelStmt *L = I->second; 3711 3712 // Verify that we have no forward references left. If so, there was a goto 3713 // or address of a label taken, but no definition of it. Label fwd 3714 // definitions are indicated with a null substmt. 3715 if (L->getSubStmt() != 0) 3716 continue; 3717 3718 // Emit error. 3719 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3720 3721 // At this point, we have gotos that use the bogus label. Stitch it into 3722 // the function body so that they aren't leaked and that the AST is well 3723 // formed. 3724 if (Body == 0) { 3725 // The whole function wasn't parsed correctly, just delete this. 3726 L->Destroy(Context); 3727 continue; 3728 } 3729 3730 // Otherwise, the body is valid: we want to stitch the label decl into the 3731 // function somewhere so that it is properly owned and so that the goto 3732 // has a valid target. Do this by creating a new compound stmt with the 3733 // label in it. 3734 3735 // Give the label a sub-statement. 3736 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3737 3738 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3739 cast<CXXTryStmt>(Body)->getTryBlock() : 3740 cast<CompoundStmt>(Body); 3741 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3742 Elements.push_back(L); 3743 Compound->setStmts(Context, &Elements[0], Elements.size()); 3744 } 3745 FunctionLabelMap.clear(); 3746 3747 if (!Body) return D; 3748 3749 // Verify that that gotos and switch cases don't jump into scopes illegally. 3750 if (CurFunctionNeedsScopeChecking) 3751 DiagnoseInvalidJumps(Body); 3752 3753 // C++ constructors that have function-try-blocks can't have return 3754 // statements in the handlers of that block. (C++ [except.handle]p14) 3755 // Verify this. 3756 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3757 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3758 3759 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3760 Destructor->computeBaseOrMembersToDestroy(Context); 3761 return D; 3762} 3763 3764/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3765/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3766NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3767 IdentifierInfo &II, Scope *S) { 3768 // Before we produce a declaration for an implicitly defined 3769 // function, see whether there was a locally-scoped declaration of 3770 // this name as a function or variable. If so, use that 3771 // (non-visible) declaration, and complain about it. 3772 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3773 = LocallyScopedExternalDecls.find(&II); 3774 if (Pos != LocallyScopedExternalDecls.end()) { 3775 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3776 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3777 return Pos->second; 3778 } 3779 3780 // Extension in C99. Legal in C90, but warn about it. 3781 if (getLangOptions().C99) 3782 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3783 else 3784 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3785 3786 // FIXME: handle stuff like: 3787 // void foo() { extern float X(); } 3788 // void bar() { X(); } <-- implicit decl for X in another scope. 3789 3790 // Set a Declarator for the implicit definition: int foo(); 3791 const char *Dummy; 3792 DeclSpec DS; 3793 unsigned DiagID; 3794 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3795 Error = Error; // Silence warning. 3796 assert(!Error && "Error setting up implicit decl!"); 3797 Declarator D(DS, Declarator::BlockContext); 3798 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3799 0, 0, false, SourceLocation(), 3800 false, 0,0,0, Loc, Loc, D), 3801 SourceLocation()); 3802 D.SetIdentifier(&II, Loc); 3803 3804 // Insert this function into translation-unit scope. 3805 3806 DeclContext *PrevDC = CurContext; 3807 CurContext = Context.getTranslationUnitDecl(); 3808 3809 FunctionDecl *FD = 3810 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3811 FD->setImplicit(); 3812 3813 CurContext = PrevDC; 3814 3815 AddKnownFunctionAttributes(FD); 3816 3817 return FD; 3818} 3819 3820/// \brief Adds any function attributes that we know a priori based on 3821/// the declaration of this function. 3822/// 3823/// These attributes can apply both to implicitly-declared builtins 3824/// (like __builtin___printf_chk) or to library-declared functions 3825/// like NSLog or printf. 3826void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3827 if (FD->isInvalidDecl()) 3828 return; 3829 3830 // If this is a built-in function, map its builtin attributes to 3831 // actual attributes. 3832 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3833 // Handle printf-formatting attributes. 3834 unsigned FormatIdx; 3835 bool HasVAListArg; 3836 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3837 if (!FD->getAttr<FormatAttr>()) 3838 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3839 HasVAListArg ? 0 : FormatIdx + 2)); 3840 } 3841 3842 // Mark const if we don't care about errno and that is the only 3843 // thing preventing the function from being const. This allows 3844 // IRgen to use LLVM intrinsics for such functions. 3845 if (!getLangOptions().MathErrno && 3846 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3847 if (!FD->getAttr<ConstAttr>()) 3848 FD->addAttr(::new (Context) ConstAttr()); 3849 } 3850 3851 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3852 FD->addAttr(::new (Context) NoReturnAttr()); 3853 } 3854 3855 IdentifierInfo *Name = FD->getIdentifier(); 3856 if (!Name) 3857 return; 3858 if ((!getLangOptions().CPlusPlus && 3859 FD->getDeclContext()->isTranslationUnit()) || 3860 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3861 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3862 LinkageSpecDecl::lang_c)) { 3863 // Okay: this could be a libc/libm/Objective-C function we know 3864 // about. 3865 } else 3866 return; 3867 3868 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3869 // FIXME: NSLog and NSLogv should be target specific 3870 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3871 // FIXME: We known better than our headers. 3872 const_cast<FormatAttr *>(Format)->setType("printf"); 3873 } else 3874 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3875 Name->isStr("NSLogv") ? 0 : 2)); 3876 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3877 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3878 // target-specific builtins, perhaps? 3879 if (!FD->getAttr<FormatAttr>()) 3880 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3881 Name->isStr("vasprintf") ? 0 : 3)); 3882 } 3883} 3884 3885TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3886 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3887 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3888 3889 // Scope manipulation handled by caller. 3890 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3891 D.getIdentifierLoc(), 3892 D.getIdentifier(), 3893 T); 3894 3895 if (TagType *TT = dyn_cast<TagType>(T)) { 3896 TagDecl *TD = TT->getDecl(); 3897 3898 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3899 // keep track of the TypedefDecl. 3900 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3901 TD->setTypedefForAnonDecl(NewTD); 3902 } 3903 3904 if (D.isInvalidType()) 3905 NewTD->setInvalidDecl(); 3906 return NewTD; 3907} 3908 3909 3910/// \brief Determine whether a tag with a given kind is acceptable 3911/// as a redeclaration of the given tag declaration. 3912/// 3913/// \returns true if the new tag kind is acceptable, false otherwise. 3914bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3915 TagDecl::TagKind NewTag, 3916 SourceLocation NewTagLoc, 3917 const IdentifierInfo &Name) { 3918 // C++ [dcl.type.elab]p3: 3919 // The class-key or enum keyword present in the 3920 // elaborated-type-specifier shall agree in kind with the 3921 // declaration to which the name in theelaborated-type-specifier 3922 // refers. This rule also applies to the form of 3923 // elaborated-type-specifier that declares a class-name or 3924 // friend class since it can be construed as referring to the 3925 // definition of the class. Thus, in any 3926 // elaborated-type-specifier, the enum keyword shall be used to 3927 // refer to an enumeration (7.2), the union class-keyshall be 3928 // used to refer to a union (clause 9), and either the class or 3929 // struct class-key shall be used to refer to a class (clause 9) 3930 // declared using the class or struct class-key. 3931 TagDecl::TagKind OldTag = Previous->getTagKind(); 3932 if (OldTag == NewTag) 3933 return true; 3934 3935 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3936 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3937 // Warn about the struct/class tag mismatch. 3938 bool isTemplate = false; 3939 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3940 isTemplate = Record->getDescribedClassTemplate(); 3941 3942 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3943 << (NewTag == TagDecl::TK_class) 3944 << isTemplate << &Name 3945 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3946 OldTag == TagDecl::TK_class? "class" : "struct"); 3947 Diag(Previous->getLocation(), diag::note_previous_use); 3948 return true; 3949 } 3950 return false; 3951} 3952 3953/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3954/// former case, Name will be non-null. In the later case, Name will be null. 3955/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3956/// reference/declaration/definition of a tag. 3957Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3958 SourceLocation KWLoc, const CXXScopeSpec &SS, 3959 IdentifierInfo *Name, SourceLocation NameLoc, 3960 AttributeList *Attr, AccessSpecifier AS, 3961 MultiTemplateParamsArg TemplateParameterLists, 3962 bool &OwnedDecl) { 3963 // If this is not a definition, it must have a name. 3964 assert((Name != 0 || TUK == TUK_Definition) && 3965 "Nameless record must be a definition!"); 3966 3967 OwnedDecl = false; 3968 TagDecl::TagKind Kind; 3969 switch (TagSpec) { 3970 default: assert(0 && "Unknown tag type!"); 3971 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3972 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3973 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3974 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3975 } 3976 3977 if (TUK != TUK_Reference) { 3978 if (TemplateParameterList *TemplateParams 3979 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3980 (TemplateParameterList**)TemplateParameterLists.get(), 3981 TemplateParameterLists.size())) { 3982 if (TemplateParams->size() > 0) { 3983 // This is a declaration or definition of a class template (which may 3984 // be a member of another template). 3985 OwnedDecl = false; 3986 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 3987 SS, Name, NameLoc, Attr, 3988 TemplateParams, 3989 AS); 3990 TemplateParameterLists.release(); 3991 return Result.get(); 3992 } else { 3993 // FIXME: diagnose the extraneous 'template<>', once we recover 3994 // slightly better in ParseTemplate.cpp from bogus template 3995 // parameters. 3996 } 3997 } 3998 } 3999 4000 DeclContext *SearchDC = CurContext; 4001 DeclContext *DC = CurContext; 4002 NamedDecl *PrevDecl = 0; 4003 4004 bool Invalid = false; 4005 4006 if (Name && SS.isNotEmpty()) { 4007 // We have a nested-name tag ('struct foo::bar'). 4008 4009 // Check for invalid 'foo::'. 4010 if (SS.isInvalid()) { 4011 Name = 0; 4012 goto CreateNewDecl; 4013 } 4014 4015 if (RequireCompleteDeclContext(SS)) 4016 return DeclPtrTy::make((Decl *)0); 4017 4018 DC = computeDeclContext(SS, true); 4019 SearchDC = DC; 4020 // Look-up name inside 'foo::'. 4021 PrevDecl 4022 = dyn_cast_or_null<TagDecl>( 4023 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4024 4025 // A tag 'foo::bar' must already exist. 4026 if (PrevDecl == 0) { 4027 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4028 Name = 0; 4029 Invalid = true; 4030 goto CreateNewDecl; 4031 } 4032 } else if (Name) { 4033 // If this is a named struct, check to see if there was a previous forward 4034 // declaration or definition. 4035 // FIXME: We're looking into outer scopes here, even when we 4036 // shouldn't be. Doing so can result in ambiguities that we 4037 // shouldn't be diagnosing. 4038 LookupResult R = LookupName(S, Name, LookupTagName, 4039 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4040 if (R.isAmbiguous()) { 4041 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4042 // FIXME: This is not best way to recover from case like: 4043 // 4044 // struct S s; 4045 // 4046 // causes needless "incomplete type" error later. 4047 Name = 0; 4048 PrevDecl = 0; 4049 Invalid = true; 4050 } else 4051 PrevDecl = R; 4052 4053 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4054 // FIXME: This makes sure that we ignore the contexts associated 4055 // with C structs, unions, and enums when looking for a matching 4056 // tag declaration or definition. See the similar lookup tweak 4057 // in Sema::LookupName; is there a better way to deal with this? 4058 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4059 SearchDC = SearchDC->getParent(); 4060 } 4061 } 4062 4063 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4064 // Maybe we will complain about the shadowed template parameter. 4065 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4066 // Just pretend that we didn't see the previous declaration. 4067 PrevDecl = 0; 4068 } 4069 4070 if (PrevDecl) { 4071 // Check whether the previous declaration is usable. 4072 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4073 4074 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4075 // If this is a use of a previous tag, or if the tag is already declared 4076 // in the same scope (so that the definition/declaration completes or 4077 // rementions the tag), reuse the decl. 4078 if (TUK == TUK_Reference || TUK == TUK_Friend || 4079 isDeclInScope(PrevDecl, SearchDC, S)) { 4080 // Make sure that this wasn't declared as an enum and now used as a 4081 // struct or something similar. 4082 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4083 bool SafeToContinue 4084 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4085 Kind != TagDecl::TK_enum); 4086 if (SafeToContinue) 4087 Diag(KWLoc, diag::err_use_with_wrong_tag) 4088 << Name 4089 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4090 PrevTagDecl->getKindName()); 4091 else 4092 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4093 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4094 4095 if (SafeToContinue) 4096 Kind = PrevTagDecl->getTagKind(); 4097 else { 4098 // Recover by making this an anonymous redefinition. 4099 Name = 0; 4100 PrevDecl = 0; 4101 Invalid = true; 4102 } 4103 } 4104 4105 if (!Invalid) { 4106 // If this is a use, just return the declaration we found. 4107 4108 // FIXME: In the future, return a variant or some other clue 4109 // for the consumer of this Decl to know it doesn't own it. 4110 // For our current ASTs this shouldn't be a problem, but will 4111 // need to be changed with DeclGroups. 4112 if (TUK == TUK_Reference) 4113 return DeclPtrTy::make(PrevDecl); 4114 4115 // If this is a friend, make sure we create the new 4116 // declaration in the appropriate semantic context. 4117 if (TUK == TUK_Friend) 4118 SearchDC = PrevDecl->getDeclContext(); 4119 4120 // Diagnose attempts to redefine a tag. 4121 if (TUK == TUK_Definition) { 4122 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4123 Diag(NameLoc, diag::err_redefinition) << Name; 4124 Diag(Def->getLocation(), diag::note_previous_definition); 4125 // If this is a redefinition, recover by making this 4126 // struct be anonymous, which will make any later 4127 // references get the previous definition. 4128 Name = 0; 4129 PrevDecl = 0; 4130 Invalid = true; 4131 } else { 4132 // If the type is currently being defined, complain 4133 // about a nested redefinition. 4134 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4135 if (Tag->isBeingDefined()) { 4136 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4137 Diag(PrevTagDecl->getLocation(), 4138 diag::note_previous_definition); 4139 Name = 0; 4140 PrevDecl = 0; 4141 Invalid = true; 4142 } 4143 } 4144 4145 // Okay, this is definition of a previously declared or referenced 4146 // tag PrevDecl. We're going to create a new Decl for it. 4147 } 4148 } 4149 // If we get here we have (another) forward declaration or we 4150 // have a definition. Just create a new decl. 4151 4152 } else { 4153 // If we get here, this is a definition of a new tag type in a nested 4154 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4155 // new decl/type. We set PrevDecl to NULL so that the entities 4156 // have distinct types. 4157 PrevDecl = 0; 4158 } 4159 // If we get here, we're going to create a new Decl. If PrevDecl 4160 // is non-NULL, it's a definition of the tag declared by 4161 // PrevDecl. If it's NULL, we have a new definition. 4162 } else { 4163 // PrevDecl is a namespace, template, or anything else 4164 // that lives in the IDNS_Tag identifier namespace. 4165 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4166 // The tag name clashes with a namespace name, issue an error and 4167 // recover by making this tag be anonymous. 4168 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4169 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4170 Name = 0; 4171 PrevDecl = 0; 4172 Invalid = true; 4173 } else { 4174 // The existing declaration isn't relevant to us; we're in a 4175 // new scope, so clear out the previous declaration. 4176 PrevDecl = 0; 4177 } 4178 } 4179 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4180 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4181 // C++ [basic.scope.pdecl]p5: 4182 // -- for an elaborated-type-specifier of the form 4183 // 4184 // class-key identifier 4185 // 4186 // if the elaborated-type-specifier is used in the 4187 // decl-specifier-seq or parameter-declaration-clause of a 4188 // function defined in namespace scope, the identifier is 4189 // declared as a class-name in the namespace that contains 4190 // the declaration; otherwise, except as a friend 4191 // declaration, the identifier is declared in the smallest 4192 // non-class, non-function-prototype scope that contains the 4193 // declaration. 4194 // 4195 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4196 // C structs and unions. 4197 // 4198 // GNU C also supports this behavior as part of its incomplete 4199 // enum types extension, while GNU C++ does not. 4200 // 4201 // Find the context where we'll be declaring the tag. 4202 // FIXME: We would like to maintain the current DeclContext as the 4203 // lexical context, 4204 while (SearchDC->isRecord()) 4205 SearchDC = SearchDC->getParent(); 4206 4207 // Find the scope where we'll be declaring the tag. 4208 while (S->isClassScope() || 4209 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4210 ((S->getFlags() & Scope::DeclScope) == 0) || 4211 (S->getEntity() && 4212 ((DeclContext *)S->getEntity())->isTransparentContext())) 4213 S = S->getParent(); 4214 4215 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4216 // C++ [namespace.memdef]p3: 4217 // If a friend declaration in a non-local class first declares a 4218 // class or function, the friend class or function is a member of 4219 // the innermost enclosing namespace. 4220 while (!SearchDC->isFileContext()) 4221 SearchDC = SearchDC->getParent(); 4222 4223 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4224 while (S->getEntity() != SearchDC) 4225 S = S->getParent(); 4226 } 4227 4228CreateNewDecl: 4229 4230 // If there is an identifier, use the location of the identifier as the 4231 // location of the decl, otherwise use the location of the struct/union 4232 // keyword. 4233 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4234 4235 // Otherwise, create a new declaration. If there is a previous 4236 // declaration of the same entity, the two will be linked via 4237 // PrevDecl. 4238 TagDecl *New; 4239 4240 if (Kind == TagDecl::TK_enum) { 4241 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4242 // enum X { A, B, C } D; D should chain to X. 4243 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4244 cast_or_null<EnumDecl>(PrevDecl)); 4245 // If this is an undefined enum, warn. 4246 if (TUK != TUK_Definition && !Invalid) { 4247 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4248 : diag::ext_forward_ref_enum; 4249 Diag(Loc, DK); 4250 } 4251 } else { 4252 // struct/union/class 4253 4254 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4255 // struct X { int A; } D; D should chain to X. 4256 if (getLangOptions().CPlusPlus) 4257 // FIXME: Look for a way to use RecordDecl for simple structs. 4258 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4259 cast_or_null<CXXRecordDecl>(PrevDecl)); 4260 else 4261 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4262 cast_or_null<RecordDecl>(PrevDecl)); 4263 } 4264 4265 if (Kind != TagDecl::TK_enum) { 4266 // Handle #pragma pack: if the #pragma pack stack has non-default 4267 // alignment, make up a packed attribute for this decl. These 4268 // attributes are checked when the ASTContext lays out the 4269 // structure. 4270 // 4271 // It is important for implementing the correct semantics that this 4272 // happen here (in act on tag decl). The #pragma pack stack is 4273 // maintained as a result of parser callbacks which can occur at 4274 // many points during the parsing of a struct declaration (because 4275 // the #pragma tokens are effectively skipped over during the 4276 // parsing of the struct). 4277 if (unsigned Alignment = getPragmaPackAlignment()) 4278 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4279 } 4280 4281 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4282 // C++ [dcl.typedef]p3: 4283 // [...] Similarly, in a given scope, a class or enumeration 4284 // shall not be declared with the same name as a typedef-name 4285 // that is declared in that scope and refers to a type other 4286 // than the class or enumeration itself. 4287 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4288 TypedefDecl *PrevTypedef = 0; 4289 if (Lookup.getKind() == LookupResult::Found) 4290 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4291 4292 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4293 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4294 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4295 Diag(Loc, diag::err_tag_definition_of_typedef) 4296 << Context.getTypeDeclType(New) 4297 << PrevTypedef->getUnderlyingType(); 4298 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4299 Invalid = true; 4300 } 4301 } 4302 4303 if (Invalid) 4304 New->setInvalidDecl(); 4305 4306 if (Attr) 4307 ProcessDeclAttributeList(S, New, Attr); 4308 4309 // If we're declaring or defining a tag in function prototype scope 4310 // in C, note that this type can only be used within the function. 4311 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4312 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4313 4314 // Set the lexical context. If the tag has a C++ scope specifier, the 4315 // lexical context will be different from the semantic context. 4316 New->setLexicalDeclContext(CurContext); 4317 4318 // Mark this as a friend decl if applicable. 4319 if (TUK == TUK_Friend) 4320 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4321 4322 // Set the access specifier. 4323 if (!Invalid && TUK != TUK_Friend) 4324 SetMemberAccessSpecifier(New, PrevDecl, AS); 4325 4326 if (TUK == TUK_Definition) 4327 New->startDefinition(); 4328 4329 // If this has an identifier, add it to the scope stack. 4330 if (Name && TUK != TUK_Friend) { 4331 S = getNonFieldDeclScope(S); 4332 PushOnScopeChains(New, S); 4333 } else { 4334 CurContext->addDecl(New); 4335 } 4336 4337 // If this is the C FILE type, notify the AST context. 4338 if (IdentifierInfo *II = New->getIdentifier()) 4339 if (!New->isInvalidDecl() && 4340 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4341 II->isStr("FILE")) 4342 Context.setFILEDecl(New); 4343 4344 OwnedDecl = true; 4345 return DeclPtrTy::make(New); 4346} 4347 4348void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4349 AdjustDeclIfTemplate(TagD); 4350 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4351 4352 // Enter the tag context. 4353 PushDeclContext(S, Tag); 4354 4355 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4356 FieldCollector->StartClass(); 4357 4358 if (Record->getIdentifier()) { 4359 // C++ [class]p2: 4360 // [...] The class-name is also inserted into the scope of the 4361 // class itself; this is known as the injected-class-name. For 4362 // purposes of access checking, the injected-class-name is treated 4363 // as if it were a public member name. 4364 CXXRecordDecl *InjectedClassName 4365 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4366 CurContext, Record->getLocation(), 4367 Record->getIdentifier(), 4368 Record->getTagKeywordLoc(), 4369 Record); 4370 InjectedClassName->setImplicit(); 4371 InjectedClassName->setAccess(AS_public); 4372 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4373 InjectedClassName->setDescribedClassTemplate(Template); 4374 PushOnScopeChains(InjectedClassName, S); 4375 assert(InjectedClassName->isInjectedClassName() && 4376 "Broken injected-class-name"); 4377 } 4378 } 4379} 4380 4381void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4382 SourceLocation RBraceLoc) { 4383 AdjustDeclIfTemplate(TagD); 4384 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4385 Tag->setRBraceLoc(RBraceLoc); 4386 4387 if (isa<CXXRecordDecl>(Tag)) 4388 FieldCollector->FinishClass(); 4389 4390 // Exit this scope of this tag's definition. 4391 PopDeclContext(); 4392 4393 // Notify the consumer that we've defined a tag. 4394 Consumer.HandleTagDeclDefinition(Tag); 4395} 4396 4397// Note that FieldName may be null for anonymous bitfields. 4398bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4399 QualType FieldTy, const Expr *BitWidth, 4400 bool *ZeroWidth) { 4401 // Default to true; that shouldn't confuse checks for emptiness 4402 if (ZeroWidth) 4403 *ZeroWidth = true; 4404 4405 // C99 6.7.2.1p4 - verify the field type. 4406 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4407 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4408 // Handle incomplete types with specific error. 4409 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4410 return true; 4411 if (FieldName) 4412 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4413 << FieldName << FieldTy << BitWidth->getSourceRange(); 4414 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4415 << FieldTy << BitWidth->getSourceRange(); 4416 } 4417 4418 // If the bit-width is type- or value-dependent, don't try to check 4419 // it now. 4420 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4421 return false; 4422 4423 llvm::APSInt Value; 4424 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4425 return true; 4426 4427 if (Value != 0 && ZeroWidth) 4428 *ZeroWidth = false; 4429 4430 // Zero-width bitfield is ok for anonymous field. 4431 if (Value == 0 && FieldName) 4432 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4433 4434 if (Value.isSigned() && Value.isNegative()) { 4435 if (FieldName) 4436 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4437 << FieldName << Value.toString(10); 4438 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4439 << Value.toString(10); 4440 } 4441 4442 if (!FieldTy->isDependentType()) { 4443 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4444 if (Value.getZExtValue() > TypeSize) { 4445 if (FieldName) 4446 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4447 << FieldName << (unsigned)TypeSize; 4448 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4449 << (unsigned)TypeSize; 4450 } 4451 } 4452 4453 return false; 4454} 4455 4456/// ActOnField - Each field of a struct/union/class is passed into this in order 4457/// to create a FieldDecl object for it. 4458Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4459 SourceLocation DeclStart, 4460 Declarator &D, ExprTy *BitfieldWidth) { 4461 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4462 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4463 AS_public); 4464 return DeclPtrTy::make(Res); 4465} 4466 4467/// HandleField - Analyze a field of a C struct or a C++ data member. 4468/// 4469FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4470 SourceLocation DeclStart, 4471 Declarator &D, Expr *BitWidth, 4472 AccessSpecifier AS) { 4473 IdentifierInfo *II = D.getIdentifier(); 4474 SourceLocation Loc = DeclStart; 4475 if (II) Loc = D.getIdentifierLoc(); 4476 4477 DeclaratorInfo *DInfo = 0; 4478 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4479 if (getLangOptions().CPlusPlus) 4480 CheckExtraCXXDefaultArguments(D); 4481 4482 DiagnoseFunctionSpecifiers(D); 4483 4484 if (D.getDeclSpec().isThreadSpecified()) 4485 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4486 4487 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4488 4489 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4490 // Maybe we will complain about the shadowed template parameter. 4491 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4492 // Just pretend that we didn't see the previous declaration. 4493 PrevDecl = 0; 4494 } 4495 4496 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4497 PrevDecl = 0; 4498 4499 bool Mutable 4500 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4501 SourceLocation TSSL = D.getSourceRange().getBegin(); 4502 FieldDecl *NewFD 4503 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4504 AS, PrevDecl, &D); 4505 if (NewFD->isInvalidDecl() && PrevDecl) { 4506 // Don't introduce NewFD into scope; there's already something 4507 // with the same name in the same scope. 4508 } else if (II) { 4509 PushOnScopeChains(NewFD, S); 4510 } else 4511 Record->addDecl(NewFD); 4512 4513 return NewFD; 4514} 4515 4516/// \brief Build a new FieldDecl and check its well-formedness. 4517/// 4518/// This routine builds a new FieldDecl given the fields name, type, 4519/// record, etc. \p PrevDecl should refer to any previous declaration 4520/// with the same name and in the same scope as the field to be 4521/// created. 4522/// 4523/// \returns a new FieldDecl. 4524/// 4525/// \todo The Declarator argument is a hack. It will be removed once 4526FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4527 DeclaratorInfo *DInfo, 4528 RecordDecl *Record, SourceLocation Loc, 4529 bool Mutable, Expr *BitWidth, 4530 SourceLocation TSSL, 4531 AccessSpecifier AS, NamedDecl *PrevDecl, 4532 Declarator *D) { 4533 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4534 bool InvalidDecl = false; 4535 if (D) InvalidDecl = D->isInvalidType(); 4536 4537 // If we receive a broken type, recover by assuming 'int' and 4538 // marking this declaration as invalid. 4539 if (T.isNull()) { 4540 InvalidDecl = true; 4541 T = Context.IntTy; 4542 } 4543 4544 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4545 // than a variably modified type. 4546 if (T->isVariablyModifiedType()) { 4547 bool SizeIsNegative; 4548 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4549 SizeIsNegative); 4550 if (!FixedTy.isNull()) { 4551 Diag(Loc, diag::warn_illegal_constant_array_size); 4552 T = FixedTy; 4553 } else { 4554 if (SizeIsNegative) 4555 Diag(Loc, diag::err_typecheck_negative_array_size); 4556 else 4557 Diag(Loc, diag::err_typecheck_field_variable_size); 4558 InvalidDecl = true; 4559 } 4560 } 4561 4562 // Fields can not have abstract class types 4563 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4564 AbstractFieldType)) 4565 InvalidDecl = true; 4566 4567 bool ZeroWidth = false; 4568 // If this is declared as a bit-field, check the bit-field. 4569 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4570 InvalidDecl = true; 4571 DeleteExpr(BitWidth); 4572 BitWidth = 0; 4573 ZeroWidth = false; 4574 } 4575 4576 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4577 BitWidth, Mutable); 4578 if (InvalidDecl) 4579 NewFD->setInvalidDecl(); 4580 4581 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4582 Diag(Loc, diag::err_duplicate_member) << II; 4583 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4584 NewFD->setInvalidDecl(); 4585 } 4586 4587 if (getLangOptions().CPlusPlus) { 4588 QualType EltTy = Context.getBaseElementType(T); 4589 4590 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4591 4592 if (!T->isPODType()) 4593 CXXRecord->setPOD(false); 4594 if (!ZeroWidth) 4595 CXXRecord->setEmpty(false); 4596 4597 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4598 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4599 4600 if (!RDecl->hasTrivialConstructor()) 4601 CXXRecord->setHasTrivialConstructor(false); 4602 if (!RDecl->hasTrivialCopyConstructor()) 4603 CXXRecord->setHasTrivialCopyConstructor(false); 4604 if (!RDecl->hasTrivialCopyAssignment()) 4605 CXXRecord->setHasTrivialCopyAssignment(false); 4606 if (!RDecl->hasTrivialDestructor()) 4607 CXXRecord->setHasTrivialDestructor(false); 4608 4609 // C++ 9.5p1: An object of a class with a non-trivial 4610 // constructor, a non-trivial copy constructor, a non-trivial 4611 // destructor, or a non-trivial copy assignment operator 4612 // cannot be a member of a union, nor can an array of such 4613 // objects. 4614 // TODO: C++0x alters this restriction significantly. 4615 if (Record->isUnion()) { 4616 // We check for copy constructors before constructors 4617 // because otherwise we'll never get complaints about 4618 // copy constructors. 4619 4620 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4621 4622 CXXSpecialMember member; 4623 if (!RDecl->hasTrivialCopyConstructor()) 4624 member = CXXCopyConstructor; 4625 else if (!RDecl->hasTrivialConstructor()) 4626 member = CXXDefaultConstructor; 4627 else if (!RDecl->hasTrivialCopyAssignment()) 4628 member = CXXCopyAssignment; 4629 else if (!RDecl->hasTrivialDestructor()) 4630 member = CXXDestructor; 4631 else 4632 member = invalid; 4633 4634 if (member != invalid) { 4635 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4636 DiagnoseNontrivial(RT, member); 4637 NewFD->setInvalidDecl(); 4638 } 4639 } 4640 } 4641 } 4642 4643 // FIXME: We need to pass in the attributes given an AST 4644 // representation, not a parser representation. 4645 if (D) 4646 // FIXME: What to pass instead of TUScope? 4647 ProcessDeclAttributes(TUScope, NewFD, *D); 4648 4649 if (T.isObjCGCWeak()) 4650 Diag(Loc, diag::warn_attribute_weak_on_field); 4651 4652 NewFD->setAccess(AS); 4653 4654 // C++ [dcl.init.aggr]p1: 4655 // An aggregate is an array or a class (clause 9) with [...] no 4656 // private or protected non-static data members (clause 11). 4657 // A POD must be an aggregate. 4658 if (getLangOptions().CPlusPlus && 4659 (AS == AS_private || AS == AS_protected)) { 4660 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4661 CXXRecord->setAggregate(false); 4662 CXXRecord->setPOD(false); 4663 } 4664 4665 return NewFD; 4666} 4667 4668/// DiagnoseNontrivial - Given that a class has a non-trivial 4669/// special member, figure out why. 4670void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4671 QualType QT(T, 0U); 4672 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4673 4674 // Check whether the member was user-declared. 4675 switch (member) { 4676 case CXXDefaultConstructor: 4677 if (RD->hasUserDeclaredConstructor()) { 4678 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4679 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4680 if (!ci->isImplicitlyDefined(Context)) { 4681 SourceLocation CtorLoc = ci->getLocation(); 4682 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4683 return; 4684 } 4685 4686 assert(0 && "found no user-declared constructors"); 4687 return; 4688 } 4689 break; 4690 4691 case CXXCopyConstructor: 4692 if (RD->hasUserDeclaredCopyConstructor()) { 4693 SourceLocation CtorLoc = 4694 RD->getCopyConstructor(Context, 0)->getLocation(); 4695 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4696 return; 4697 } 4698 break; 4699 4700 case CXXCopyAssignment: 4701 if (RD->hasUserDeclaredCopyAssignment()) { 4702 // FIXME: this should use the location of the copy 4703 // assignment, not the type. 4704 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4705 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4706 return; 4707 } 4708 break; 4709 4710 case CXXDestructor: 4711 if (RD->hasUserDeclaredDestructor()) { 4712 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4713 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4714 return; 4715 } 4716 break; 4717 } 4718 4719 typedef CXXRecordDecl::base_class_iterator base_iter; 4720 4721 // Virtual bases and members inhibit trivial copying/construction, 4722 // but not trivial destruction. 4723 if (member != CXXDestructor) { 4724 // Check for virtual bases. vbases includes indirect virtual bases, 4725 // so we just iterate through the direct bases. 4726 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4727 if (bi->isVirtual()) { 4728 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4729 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4730 return; 4731 } 4732 4733 // Check for virtual methods. 4734 typedef CXXRecordDecl::method_iterator meth_iter; 4735 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4736 ++mi) { 4737 if (mi->isVirtual()) { 4738 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4739 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4740 return; 4741 } 4742 } 4743 } 4744 4745 bool (CXXRecordDecl::*hasTrivial)() const; 4746 switch (member) { 4747 case CXXDefaultConstructor: 4748 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4749 case CXXCopyConstructor: 4750 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4751 case CXXCopyAssignment: 4752 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4753 case CXXDestructor: 4754 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4755 default: 4756 assert(0 && "unexpected special member"); return; 4757 } 4758 4759 // Check for nontrivial bases (and recurse). 4760 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4761 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4762 assert(BaseRT); 4763 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4764 if (!(BaseRecTy->*hasTrivial)()) { 4765 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4766 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4767 DiagnoseNontrivial(BaseRT, member); 4768 return; 4769 } 4770 } 4771 4772 // Check for nontrivial members (and recurse). 4773 typedef RecordDecl::field_iterator field_iter; 4774 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4775 ++fi) { 4776 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4777 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4778 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4779 4780 if (!(EltRD->*hasTrivial)()) { 4781 SourceLocation FLoc = (*fi)->getLocation(); 4782 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4783 DiagnoseNontrivial(EltRT, member); 4784 return; 4785 } 4786 } 4787 } 4788 4789 assert(0 && "found no explanation for non-trivial member"); 4790} 4791 4792/// TranslateIvarVisibility - Translate visibility from a token ID to an 4793/// AST enum value. 4794static ObjCIvarDecl::AccessControl 4795TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4796 switch (ivarVisibility) { 4797 default: assert(0 && "Unknown visitibility kind"); 4798 case tok::objc_private: return ObjCIvarDecl::Private; 4799 case tok::objc_public: return ObjCIvarDecl::Public; 4800 case tok::objc_protected: return ObjCIvarDecl::Protected; 4801 case tok::objc_package: return ObjCIvarDecl::Package; 4802 } 4803} 4804 4805/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4806/// in order to create an IvarDecl object for it. 4807Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4808 SourceLocation DeclStart, 4809 DeclPtrTy IntfDecl, 4810 Declarator &D, ExprTy *BitfieldWidth, 4811 tok::ObjCKeywordKind Visibility) { 4812 4813 IdentifierInfo *II = D.getIdentifier(); 4814 Expr *BitWidth = (Expr*)BitfieldWidth; 4815 SourceLocation Loc = DeclStart; 4816 if (II) Loc = D.getIdentifierLoc(); 4817 4818 // FIXME: Unnamed fields can be handled in various different ways, for 4819 // example, unnamed unions inject all members into the struct namespace! 4820 4821 DeclaratorInfo *DInfo = 0; 4822 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4823 4824 if (BitWidth) { 4825 // 6.7.2.1p3, 6.7.2.1p4 4826 if (VerifyBitField(Loc, II, T, BitWidth)) { 4827 D.setInvalidType(); 4828 DeleteExpr(BitWidth); 4829 BitWidth = 0; 4830 } 4831 } else { 4832 // Not a bitfield. 4833 4834 // validate II. 4835 4836 } 4837 4838 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4839 // than a variably modified type. 4840 if (T->isVariablyModifiedType()) { 4841 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4842 D.setInvalidType(); 4843 } 4844 4845 // Get the visibility (access control) for this ivar. 4846 ObjCIvarDecl::AccessControl ac = 4847 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4848 : ObjCIvarDecl::None; 4849 // Must set ivar's DeclContext to its enclosing interface. 4850 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4851 DeclContext *EnclosingContext; 4852 if (ObjCImplementationDecl *IMPDecl = 4853 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4854 // Case of ivar declared in an implementation. Context is that of its class. 4855 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4856 assert(IDecl && "No class- ActOnIvar"); 4857 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4858 } else 4859 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4860 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4861 4862 // Construct the decl. 4863 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4864 EnclosingContext, Loc, II, T, 4865 DInfo, ac, (Expr *)BitfieldWidth); 4866 4867 if (II) { 4868 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4869 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4870 && !isa<TagDecl>(PrevDecl)) { 4871 Diag(Loc, diag::err_duplicate_member) << II; 4872 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4873 NewID->setInvalidDecl(); 4874 } 4875 } 4876 4877 // Process attributes attached to the ivar. 4878 ProcessDeclAttributes(S, NewID, D); 4879 4880 if (D.isInvalidType()) 4881 NewID->setInvalidDecl(); 4882 4883 if (II) { 4884 // FIXME: When interfaces are DeclContexts, we'll need to add 4885 // these to the interface. 4886 S->AddDecl(DeclPtrTy::make(NewID)); 4887 IdResolver.AddDecl(NewID); 4888 } 4889 4890 return DeclPtrTy::make(NewID); 4891} 4892 4893void Sema::ActOnFields(Scope* S, 4894 SourceLocation RecLoc, DeclPtrTy RecDecl, 4895 DeclPtrTy *Fields, unsigned NumFields, 4896 SourceLocation LBrac, SourceLocation RBrac, 4897 AttributeList *Attr) { 4898 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4899 assert(EnclosingDecl && "missing record or interface decl"); 4900 4901 // If the decl this is being inserted into is invalid, then it may be a 4902 // redeclaration or some other bogus case. Don't try to add fields to it. 4903 if (EnclosingDecl->isInvalidDecl()) { 4904 // FIXME: Deallocate fields? 4905 return; 4906 } 4907 4908 4909 // Verify that all the fields are okay. 4910 unsigned NumNamedMembers = 0; 4911 llvm::SmallVector<FieldDecl*, 32> RecFields; 4912 4913 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4914 for (unsigned i = 0; i != NumFields; ++i) { 4915 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4916 4917 // Get the type for the field. 4918 Type *FDTy = FD->getType().getTypePtr(); 4919 4920 if (!FD->isAnonymousStructOrUnion()) { 4921 // Remember all fields written by the user. 4922 RecFields.push_back(FD); 4923 } 4924 4925 // If the field is already invalid for some reason, don't emit more 4926 // diagnostics about it. 4927 if (FD->isInvalidDecl()) 4928 continue; 4929 4930 // C99 6.7.2.1p2: 4931 // A structure or union shall not contain a member with 4932 // incomplete or function type (hence, a structure shall not 4933 // contain an instance of itself, but may contain a pointer to 4934 // an instance of itself), except that the last member of a 4935 // structure with more than one named member may have incomplete 4936 // array type; such a structure (and any union containing, 4937 // possibly recursively, a member that is such a structure) 4938 // shall not be a member of a structure or an element of an 4939 // array. 4940 if (FDTy->isFunctionType()) { 4941 // Field declared as a function. 4942 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4943 << FD->getDeclName(); 4944 FD->setInvalidDecl(); 4945 EnclosingDecl->setInvalidDecl(); 4946 continue; 4947 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4948 Record && Record->isStruct()) { 4949 // Flexible array member. 4950 if (NumNamedMembers < 1) { 4951 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4952 << FD->getDeclName(); 4953 FD->setInvalidDecl(); 4954 EnclosingDecl->setInvalidDecl(); 4955 continue; 4956 } 4957 // Okay, we have a legal flexible array member at the end of the struct. 4958 if (Record) 4959 Record->setHasFlexibleArrayMember(true); 4960 } else if (!FDTy->isDependentType() && 4961 RequireCompleteType(FD->getLocation(), FD->getType(), 4962 diag::err_field_incomplete)) { 4963 // Incomplete type 4964 FD->setInvalidDecl(); 4965 EnclosingDecl->setInvalidDecl(); 4966 continue; 4967 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 4968 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4969 // If this is a member of a union, then entire union becomes "flexible". 4970 if (Record && Record->isUnion()) { 4971 Record->setHasFlexibleArrayMember(true); 4972 } else { 4973 // If this is a struct/class and this is not the last element, reject 4974 // it. Note that GCC supports variable sized arrays in the middle of 4975 // structures. 4976 if (i != NumFields-1) 4977 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4978 << FD->getDeclName() << FD->getType(); 4979 else { 4980 // We support flexible arrays at the end of structs in 4981 // other structs as an extension. 4982 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4983 << FD->getDeclName(); 4984 if (Record) 4985 Record->setHasFlexibleArrayMember(true); 4986 } 4987 } 4988 } 4989 if (Record && FDTTy->getDecl()->hasObjectMember()) 4990 Record->setHasObjectMember(true); 4991 } else if (FDTy->isObjCInterfaceType()) { 4992 /// A field cannot be an Objective-c object 4993 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4994 FD->setInvalidDecl(); 4995 EnclosingDecl->setInvalidDecl(); 4996 continue; 4997 } else if (getLangOptions().ObjC1 && 4998 getLangOptions().getGCMode() != LangOptions::NonGC && 4999 Record && 5000 (FD->getType()->isObjCObjectPointerType() || 5001 FD->getType().isObjCGCStrong())) 5002 Record->setHasObjectMember(true); 5003 // Keep track of the number of named members. 5004 if (FD->getIdentifier()) 5005 ++NumNamedMembers; 5006 } 5007 5008 // Okay, we successfully defined 'Record'. 5009 if (Record) { 5010 Record->completeDefinition(Context); 5011 } else { 5012 ObjCIvarDecl **ClsFields = 5013 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5014 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5015 ID->setIVarList(ClsFields, RecFields.size(), Context); 5016 ID->setLocEnd(RBrac); 5017 // Add ivar's to class's DeclContext. 5018 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5019 ClsFields[i]->setLexicalDeclContext(ID); 5020 ID->addDecl(ClsFields[i]); 5021 } 5022 // Must enforce the rule that ivars in the base classes may not be 5023 // duplicates. 5024 if (ID->getSuperClass()) { 5025 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5026 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5027 ObjCIvarDecl* Ivar = (*IVI); 5028 5029 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5030 ObjCIvarDecl* prevIvar = 5031 ID->getSuperClass()->lookupInstanceVariable(II); 5032 if (prevIvar) { 5033 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5034 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5035 } 5036 } 5037 } 5038 } 5039 } else if (ObjCImplementationDecl *IMPDecl = 5040 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5041 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5042 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5043 // Ivar declared in @implementation never belongs to the implementation. 5044 // Only it is in implementation's lexical context. 5045 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5046 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5047 } 5048 } 5049 5050 if (Attr) 5051 ProcessDeclAttributeList(S, Record, Attr); 5052} 5053 5054EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5055 EnumConstantDecl *LastEnumConst, 5056 SourceLocation IdLoc, 5057 IdentifierInfo *Id, 5058 ExprArg val) { 5059 Expr *Val = (Expr *)val.get(); 5060 5061 llvm::APSInt EnumVal(32); 5062 QualType EltTy; 5063 if (Val && !Val->isTypeDependent()) { 5064 // Make sure to promote the operand type to int. 5065 UsualUnaryConversions(Val); 5066 if (Val != val.get()) { 5067 val.release(); 5068 val = Val; 5069 } 5070 5071 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5072 SourceLocation ExpLoc; 5073 if (!Val->isValueDependent() && 5074 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5075 Val = 0; 5076 } else { 5077 EltTy = Val->getType(); 5078 } 5079 } 5080 5081 if (!Val) { 5082 if (LastEnumConst) { 5083 // Assign the last value + 1. 5084 EnumVal = LastEnumConst->getInitVal(); 5085 ++EnumVal; 5086 5087 // Check for overflow on increment. 5088 if (EnumVal < LastEnumConst->getInitVal()) 5089 Diag(IdLoc, diag::warn_enum_value_overflow); 5090 5091 EltTy = LastEnumConst->getType(); 5092 } else { 5093 // First value, set to zero. 5094 EltTy = Context.IntTy; 5095 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5096 } 5097 } 5098 5099 val.release(); 5100 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5101 Val, EnumVal); 5102} 5103 5104 5105Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5106 DeclPtrTy lastEnumConst, 5107 SourceLocation IdLoc, 5108 IdentifierInfo *Id, 5109 SourceLocation EqualLoc, ExprTy *val) { 5110 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5111 EnumConstantDecl *LastEnumConst = 5112 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5113 Expr *Val = static_cast<Expr*>(val); 5114 5115 // The scope passed in may not be a decl scope. Zip up the scope tree until 5116 // we find one that is. 5117 S = getNonFieldDeclScope(S); 5118 5119 // Verify that there isn't already something declared with this name in this 5120 // scope. 5121 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5122 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5123 // Maybe we will complain about the shadowed template parameter. 5124 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5125 // Just pretend that we didn't see the previous declaration. 5126 PrevDecl = 0; 5127 } 5128 5129 if (PrevDecl) { 5130 // When in C++, we may get a TagDecl with the same name; in this case the 5131 // enum constant will 'hide' the tag. 5132 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5133 "Received TagDecl when not in C++!"); 5134 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5135 if (isa<EnumConstantDecl>(PrevDecl)) 5136 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5137 else 5138 Diag(IdLoc, diag::err_redefinition) << Id; 5139 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5140 if (Val) Val->Destroy(Context); 5141 return DeclPtrTy(); 5142 } 5143 } 5144 5145 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5146 IdLoc, Id, Owned(Val)); 5147 5148 // Register this decl in the current scope stack. 5149 if (New) 5150 PushOnScopeChains(New, S); 5151 5152 return DeclPtrTy::make(New); 5153} 5154 5155void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5156 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5157 DeclPtrTy *Elements, unsigned NumElements, 5158 Scope *S, AttributeList *Attr) { 5159 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5160 QualType EnumType = Context.getTypeDeclType(Enum); 5161 5162 if (Attr) 5163 ProcessDeclAttributeList(S, Enum, Attr); 5164 5165 // TODO: If the result value doesn't fit in an int, it must be a long or long 5166 // long value. ISO C does not support this, but GCC does as an extension, 5167 // emit a warning. 5168 unsigned IntWidth = Context.Target.getIntWidth(); 5169 unsigned CharWidth = Context.Target.getCharWidth(); 5170 unsigned ShortWidth = Context.Target.getShortWidth(); 5171 5172 // Verify that all the values are okay, compute the size of the values, and 5173 // reverse the list. 5174 unsigned NumNegativeBits = 0; 5175 unsigned NumPositiveBits = 0; 5176 5177 // Keep track of whether all elements have type int. 5178 bool AllElementsInt = true; 5179 5180 for (unsigned i = 0; i != NumElements; ++i) { 5181 EnumConstantDecl *ECD = 5182 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5183 if (!ECD) continue; // Already issued a diagnostic. 5184 5185 // If the enum value doesn't fit in an int, emit an extension warning. 5186 const llvm::APSInt &InitVal = ECD->getInitVal(); 5187 assert(InitVal.getBitWidth() >= IntWidth && 5188 "Should have promoted value to int"); 5189 if (InitVal.getBitWidth() > IntWidth) { 5190 llvm::APSInt V(InitVal); 5191 V.trunc(IntWidth); 5192 V.extend(InitVal.getBitWidth()); 5193 if (V != InitVal) 5194 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5195 << InitVal.toString(10); 5196 } 5197 5198 // Keep track of the size of positive and negative values. 5199 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5200 NumPositiveBits = std::max(NumPositiveBits, 5201 (unsigned)InitVal.getActiveBits()); 5202 else 5203 NumNegativeBits = std::max(NumNegativeBits, 5204 (unsigned)InitVal.getMinSignedBits()); 5205 5206 // Keep track of whether every enum element has type int (very commmon). 5207 if (AllElementsInt) 5208 AllElementsInt = ECD->getType() == Context.IntTy; 5209 } 5210 5211 // Figure out the type that should be used for this enum. 5212 // FIXME: Support -fshort-enums. 5213 QualType BestType; 5214 unsigned BestWidth; 5215 5216 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5217 5218 if (NumNegativeBits) { 5219 // If there is a negative value, figure out the smallest integer type (of 5220 // int/long/longlong) that fits. 5221 // If it's packed, check also if it fits a char or a short. 5222 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5223 BestType = Context.SignedCharTy; 5224 BestWidth = CharWidth; 5225 } else if (Packed && NumNegativeBits <= ShortWidth && 5226 NumPositiveBits < ShortWidth) { 5227 BestType = Context.ShortTy; 5228 BestWidth = ShortWidth; 5229 } 5230 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5231 BestType = Context.IntTy; 5232 BestWidth = IntWidth; 5233 } else { 5234 BestWidth = Context.Target.getLongWidth(); 5235 5236 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5237 BestType = Context.LongTy; 5238 else { 5239 BestWidth = Context.Target.getLongLongWidth(); 5240 5241 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5242 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5243 BestType = Context.LongLongTy; 5244 } 5245 } 5246 } else { 5247 // If there is no negative value, figure out which of uint, ulong, ulonglong 5248 // fits. 5249 // If it's packed, check also if it fits a char or a short. 5250 if (Packed && NumPositiveBits <= CharWidth) { 5251 BestType = Context.UnsignedCharTy; 5252 BestWidth = CharWidth; 5253 } else if (Packed && NumPositiveBits <= ShortWidth) { 5254 BestType = Context.UnsignedShortTy; 5255 BestWidth = ShortWidth; 5256 } 5257 else if (NumPositiveBits <= IntWidth) { 5258 BestType = Context.UnsignedIntTy; 5259 BestWidth = IntWidth; 5260 } else if (NumPositiveBits <= 5261 (BestWidth = Context.Target.getLongWidth())) { 5262 BestType = Context.UnsignedLongTy; 5263 } else { 5264 BestWidth = Context.Target.getLongLongWidth(); 5265 assert(NumPositiveBits <= BestWidth && 5266 "How could an initializer get larger than ULL?"); 5267 BestType = Context.UnsignedLongLongTy; 5268 } 5269 } 5270 5271 // Loop over all of the enumerator constants, changing their types to match 5272 // the type of the enum if needed. 5273 for (unsigned i = 0; i != NumElements; ++i) { 5274 EnumConstantDecl *ECD = 5275 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5276 if (!ECD) continue; // Already issued a diagnostic. 5277 5278 // Standard C says the enumerators have int type, but we allow, as an 5279 // extension, the enumerators to be larger than int size. If each 5280 // enumerator value fits in an int, type it as an int, otherwise type it the 5281 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5282 // that X has type 'int', not 'unsigned'. 5283 if (ECD->getType() == Context.IntTy) { 5284 // Make sure the init value is signed. 5285 llvm::APSInt IV = ECD->getInitVal(); 5286 IV.setIsSigned(true); 5287 ECD->setInitVal(IV); 5288 5289 if (getLangOptions().CPlusPlus) 5290 // C++ [dcl.enum]p4: Following the closing brace of an 5291 // enum-specifier, each enumerator has the type of its 5292 // enumeration. 5293 ECD->setType(EnumType); 5294 continue; // Already int type. 5295 } 5296 5297 // Determine whether the value fits into an int. 5298 llvm::APSInt InitVal = ECD->getInitVal(); 5299 bool FitsInInt; 5300 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5301 FitsInInt = InitVal.getActiveBits() < IntWidth; 5302 else 5303 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5304 5305 // If it fits into an integer type, force it. Otherwise force it to match 5306 // the enum decl type. 5307 QualType NewTy; 5308 unsigned NewWidth; 5309 bool NewSign; 5310 if (FitsInInt) { 5311 NewTy = Context.IntTy; 5312 NewWidth = IntWidth; 5313 NewSign = true; 5314 } else if (ECD->getType() == BestType) { 5315 // Already the right type! 5316 if (getLangOptions().CPlusPlus) 5317 // C++ [dcl.enum]p4: Following the closing brace of an 5318 // enum-specifier, each enumerator has the type of its 5319 // enumeration. 5320 ECD->setType(EnumType); 5321 continue; 5322 } else { 5323 NewTy = BestType; 5324 NewWidth = BestWidth; 5325 NewSign = BestType->isSignedIntegerType(); 5326 } 5327 5328 // Adjust the APSInt value. 5329 InitVal.extOrTrunc(NewWidth); 5330 InitVal.setIsSigned(NewSign); 5331 ECD->setInitVal(InitVal); 5332 5333 // Adjust the Expr initializer and type. 5334 if (ECD->getInitExpr()) 5335 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5336 CastExpr::CK_Unknown, 5337 ECD->getInitExpr(), 5338 /*isLvalue=*/false)); 5339 if (getLangOptions().CPlusPlus) 5340 // C++ [dcl.enum]p4: Following the closing brace of an 5341 // enum-specifier, each enumerator has the type of its 5342 // enumeration. 5343 ECD->setType(EnumType); 5344 else 5345 ECD->setType(NewTy); 5346 } 5347 5348 Enum->completeDefinition(Context, BestType); 5349} 5350 5351Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5352 ExprArg expr) { 5353 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5354 5355 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5356 Loc, AsmString); 5357 CurContext->addDecl(New); 5358 return DeclPtrTy::make(New); 5359} 5360 5361void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5362 SourceLocation PragmaLoc, 5363 SourceLocation NameLoc) { 5364 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5365 5366 if (PrevDecl) { 5367 PrevDecl->addAttr(::new (Context) WeakAttr()); 5368 } else { 5369 (void)WeakUndeclaredIdentifiers.insert( 5370 std::pair<IdentifierInfo*,WeakInfo> 5371 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5372 } 5373} 5374 5375void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5376 IdentifierInfo* AliasName, 5377 SourceLocation PragmaLoc, 5378 SourceLocation NameLoc, 5379 SourceLocation AliasNameLoc) { 5380 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5381 WeakInfo W = WeakInfo(Name, NameLoc); 5382 5383 if (PrevDecl) { 5384 if (!PrevDecl->hasAttr<AliasAttr>()) 5385 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5386 DeclApplyPragmaWeak(TUScope, ND, W); 5387 } else { 5388 (void)WeakUndeclaredIdentifiers.insert( 5389 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5390 } 5391} 5392