SemaDecl.cpp revision b9aa6b214c8fbc3e081dde575eef1f0913d48bdc
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/Analysis/CFG.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Basic/PartialDiagnostic.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/Basic/TargetInfo.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/BitVector.h" 33#include "llvm/ADT/STLExtras.h" 34#include <algorithm> 35#include <functional> 36#include <queue> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, const CXXScopeSpec *SS, 65 bool isClassName) { 66 // C++ [temp.res]p3: 67 // A qualified-id that refers to a type and in which the 68 // nested-name-specifier depends on a template-parameter (14.6.2) 69 // shall be prefixed by the keyword typename to indicate that the 70 // qualified-id denotes a type, forming an 71 // elaborated-type-specifier (7.1.5.3). 72 // 73 // We therefore do not perform any name lookup if the result would 74 // refer to a member of an unknown specialization. 75 if (SS && isUnknownSpecialization(*SS)) { 76 if (!isClassName) 77 return 0; 78 79 // We know from the grammar that this name refers to a type, so build a 80 // TypenameType node to describe the type. 81 // FIXME: Record somewhere that this TypenameType node has no "typename" 82 // keyword associated with it. 83 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 84 II, SS->getRange()).getAsOpaquePtr(); 85 } 86 87 LookupResult Result 88 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 89 90 NamedDecl *IIDecl = 0; 91 switch (Result.getKind()) { 92 case LookupResult::NotFound: 93 case LookupResult::FoundOverloaded: 94 return 0; 95 96 case LookupResult::AmbiguousBaseSubobjectTypes: 97 case LookupResult::AmbiguousBaseSubobjects: 98 case LookupResult::AmbiguousReference: { 99 // Look to see if we have a type anywhere in the list of results. 100 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 101 Res != ResEnd; ++Res) { 102 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 103 if (!IIDecl || 104 (*Res)->getLocation().getRawEncoding() < 105 IIDecl->getLocation().getRawEncoding()) 106 IIDecl = *Res; 107 } 108 } 109 110 if (!IIDecl) { 111 // None of the entities we found is a type, so there is no way 112 // to even assume that the result is a type. In this case, don't 113 // complain about the ambiguity. The parser will either try to 114 // perform this lookup again (e.g., as an object name), which 115 // will produce the ambiguity, or will complain that it expected 116 // a type name. 117 Result.Destroy(); 118 return 0; 119 } 120 121 // We found a type within the ambiguous lookup; diagnose the 122 // ambiguity and then return that type. This might be the right 123 // answer, or it might not be, but it suppresses any attempt to 124 // perform the name lookup again. 125 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 126 break; 127 } 128 129 case LookupResult::Found: 130 IIDecl = Result.getAsDecl(); 131 break; 132 } 133 134 if (IIDecl) { 135 QualType T; 136 137 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 138 // Check whether we can use this type 139 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 140 141 if (getLangOptions().CPlusPlus) { 142 // C++ [temp.local]p2: 143 // Within the scope of a class template specialization or 144 // partial specialization, when the injected-class-name is 145 // not followed by a <, it is equivalent to the 146 // injected-class-name followed by the template-argument s 147 // of the class template specialization or partial 148 // specialization enclosed in <>. 149 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 150 if (RD->isInjectedClassName()) 151 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 152 T = Template->getInjectedClassNameType(Context); 153 } 154 155 if (T.isNull()) 156 T = Context.getTypeDeclType(TD); 157 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 158 // Check whether we can use this interface. 159 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 160 161 T = Context.getObjCInterfaceType(IDecl); 162 } else 163 return 0; 164 165 if (SS) 166 T = getQualifiedNameType(*SS, T); 167 168 return T.getAsOpaquePtr(); 169 } 170 171 return 0; 172} 173 174/// isTagName() - This method is called *for error recovery purposes only* 175/// to determine if the specified name is a valid tag name ("struct foo"). If 176/// so, this returns the TST for the tag corresponding to it (TST_enum, 177/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 178/// where the user forgot to specify the tag. 179DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 180 // Do a tag name lookup in this scope. 181 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 182 if (R.getKind() == LookupResult::Found) 183 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 184 switch (TD->getTagKind()) { 185 case TagDecl::TK_struct: return DeclSpec::TST_struct; 186 case TagDecl::TK_union: return DeclSpec::TST_union; 187 case TagDecl::TK_class: return DeclSpec::TST_class; 188 case TagDecl::TK_enum: return DeclSpec::TST_enum; 189 } 190 } 191 192 return DeclSpec::TST_unspecified; 193} 194 195 196// Determines the context to return to after temporarily entering a 197// context. This depends in an unnecessarily complicated way on the 198// exact ordering of callbacks from the parser. 199DeclContext *Sema::getContainingDC(DeclContext *DC) { 200 201 // Functions defined inline within classes aren't parsed until we've 202 // finished parsing the top-level class, so the top-level class is 203 // the context we'll need to return to. 204 if (isa<FunctionDecl>(DC)) { 205 DC = DC->getLexicalParent(); 206 207 // A function not defined within a class will always return to its 208 // lexical context. 209 if (!isa<CXXRecordDecl>(DC)) 210 return DC; 211 212 // A C++ inline method/friend is parsed *after* the topmost class 213 // it was declared in is fully parsed ("complete"); the topmost 214 // class is the context we need to return to. 215 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 216 DC = RD; 217 218 // Return the declaration context of the topmost class the inline method is 219 // declared in. 220 return DC; 221 } 222 223 if (isa<ObjCMethodDecl>(DC)) 224 return Context.getTranslationUnitDecl(); 225 226 return DC->getLexicalParent(); 227} 228 229void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 230 assert(getContainingDC(DC) == CurContext && 231 "The next DeclContext should be lexically contained in the current one."); 232 CurContext = DC; 233 S->setEntity(DC); 234} 235 236void Sema::PopDeclContext() { 237 assert(CurContext && "DeclContext imbalance!"); 238 239 CurContext = getContainingDC(CurContext); 240} 241 242/// EnterDeclaratorContext - Used when we must lookup names in the context 243/// of a declarator's nested name specifier. 244void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 245 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 246 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 247 CurContext = DC; 248 assert(CurContext && "No context?"); 249 S->setEntity(CurContext); 250} 251 252void Sema::ExitDeclaratorContext(Scope *S) { 253 S->setEntity(PreDeclaratorDC); 254 PreDeclaratorDC = 0; 255 256 // Reset CurContext to the nearest enclosing context. 257 while (!S->getEntity() && S->getParent()) 258 S = S->getParent(); 259 CurContext = static_cast<DeclContext*>(S->getEntity()); 260 assert(CurContext && "No context?"); 261} 262 263/// \brief Determine whether we allow overloading of the function 264/// PrevDecl with another declaration. 265/// 266/// This routine determines whether overloading is possible, not 267/// whether some new function is actually an overload. It will return 268/// true in C++ (where we can always provide overloads) or, as an 269/// extension, in C when the previous function is already an 270/// overloaded function declaration or has the "overloadable" 271/// attribute. 272static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 273 if (Context.getLangOptions().CPlusPlus) 274 return true; 275 276 if (isa<OverloadedFunctionDecl>(PrevDecl)) 277 return true; 278 279 return PrevDecl->getAttr<OverloadableAttr>() != 0; 280} 281 282/// Add this decl to the scope shadowed decl chains. 283void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 284 // Move up the scope chain until we find the nearest enclosing 285 // non-transparent context. The declaration will be introduced into this 286 // scope. 287 while (S->getEntity() && 288 ((DeclContext *)S->getEntity())->isTransparentContext()) 289 S = S->getParent(); 290 291 S->AddDecl(DeclPtrTy::make(D)); 292 293 // Add scoped declarations into their context, so that they can be 294 // found later. Declarations without a context won't be inserted 295 // into any context. 296 if (AddToContext) 297 CurContext->addDecl(D); 298 299 // C++ [basic.scope]p4: 300 // -- exactly one declaration shall declare a class name or 301 // enumeration name that is not a typedef name and the other 302 // declarations shall all refer to the same object or 303 // enumerator, or all refer to functions and function templates; 304 // in this case the class name or enumeration name is hidden. 305 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 306 // We are pushing the name of a tag (enum or class). 307 if (CurContext->getLookupContext() 308 == TD->getDeclContext()->getLookupContext()) { 309 // We're pushing the tag into the current context, which might 310 // require some reshuffling in the identifier resolver. 311 IdentifierResolver::iterator 312 I = IdResolver.begin(TD->getDeclName()), 313 IEnd = IdResolver.end(); 314 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 315 NamedDecl *PrevDecl = *I; 316 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 317 PrevDecl = *I, ++I) { 318 if (TD->declarationReplaces(*I)) { 319 // This is a redeclaration. Remove it from the chain and 320 // break out, so that we'll add in the shadowed 321 // declaration. 322 S->RemoveDecl(DeclPtrTy::make(*I)); 323 if (PrevDecl == *I) { 324 IdResolver.RemoveDecl(*I); 325 IdResolver.AddDecl(TD); 326 return; 327 } else { 328 IdResolver.RemoveDecl(*I); 329 break; 330 } 331 } 332 } 333 334 // There is already a declaration with the same name in the same 335 // scope, which is not a tag declaration. It must be found 336 // before we find the new declaration, so insert the new 337 // declaration at the end of the chain. 338 IdResolver.AddShadowedDecl(TD, PrevDecl); 339 340 return; 341 } 342 } 343 } else if ((isa<FunctionDecl>(D) && 344 AllowOverloadingOfFunction(D, Context)) || 345 isa<FunctionTemplateDecl>(D)) { 346 // We are pushing the name of a function or function template, 347 // which might be an overloaded name. 348 IdentifierResolver::iterator Redecl 349 = std::find_if(IdResolver.begin(D->getDeclName()), 350 IdResolver.end(), 351 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 352 D)); 353 if (Redecl != IdResolver.end() && 354 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 355 // There is already a declaration of a function on our 356 // IdResolver chain. Replace it with this declaration. 357 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 358 IdResolver.RemoveDecl(*Redecl); 359 } 360 } else if (isa<ObjCInterfaceDecl>(D)) { 361 // We're pushing an Objective-C interface into the current 362 // context. If there is already an alias declaration, remove it first. 363 for (IdentifierResolver::iterator 364 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 365 I != IEnd; ++I) { 366 if (isa<ObjCCompatibleAliasDecl>(*I)) { 367 S->RemoveDecl(DeclPtrTy::make(*I)); 368 IdResolver.RemoveDecl(*I); 369 break; 370 } 371 } 372 } 373 374 IdResolver.AddDecl(D); 375} 376 377void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 378 if (S->decl_empty()) return; 379 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 380 "Scope shouldn't contain decls!"); 381 382 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 383 I != E; ++I) { 384 Decl *TmpD = (*I).getAs<Decl>(); 385 assert(TmpD && "This decl didn't get pushed??"); 386 387 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 388 NamedDecl *D = cast<NamedDecl>(TmpD); 389 390 if (!D->getDeclName()) continue; 391 392 // Remove this name from our lexical scope. 393 IdResolver.RemoveDecl(D); 394 } 395} 396 397/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 398/// return 0 if one not found. 399ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 400 // The third "scope" argument is 0 since we aren't enabling lazy built-in 401 // creation from this context. 402 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 403 404 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 405} 406 407/// getNonFieldDeclScope - Retrieves the innermost scope, starting 408/// from S, where a non-field would be declared. This routine copes 409/// with the difference between C and C++ scoping rules in structs and 410/// unions. For example, the following code is well-formed in C but 411/// ill-formed in C++: 412/// @code 413/// struct S6 { 414/// enum { BAR } e; 415/// }; 416/// 417/// void test_S6() { 418/// struct S6 a; 419/// a.e = BAR; 420/// } 421/// @endcode 422/// For the declaration of BAR, this routine will return a different 423/// scope. The scope S will be the scope of the unnamed enumeration 424/// within S6. In C++, this routine will return the scope associated 425/// with S6, because the enumeration's scope is a transparent 426/// context but structures can contain non-field names. In C, this 427/// routine will return the translation unit scope, since the 428/// enumeration's scope is a transparent context and structures cannot 429/// contain non-field names. 430Scope *Sema::getNonFieldDeclScope(Scope *S) { 431 while (((S->getFlags() & Scope::DeclScope) == 0) || 432 (S->getEntity() && 433 ((DeclContext *)S->getEntity())->isTransparentContext()) || 434 (S->isClassScope() && !getLangOptions().CPlusPlus)) 435 S = S->getParent(); 436 return S; 437} 438 439void Sema::InitBuiltinVaListType() { 440 if (!Context.getBuiltinVaListType().isNull()) 441 return; 442 443 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 444 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 445 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 446 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 447} 448 449/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 450/// file scope. lazily create a decl for it. ForRedeclaration is true 451/// if we're creating this built-in in anticipation of redeclaring the 452/// built-in. 453NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 454 Scope *S, bool ForRedeclaration, 455 SourceLocation Loc) { 456 Builtin::ID BID = (Builtin::ID)bid; 457 458 if (Context.BuiltinInfo.hasVAListUse(BID)) 459 InitBuiltinVaListType(); 460 461 ASTContext::GetBuiltinTypeError Error; 462 QualType R = Context.GetBuiltinType(BID, Error); 463 switch (Error) { 464 case ASTContext::GE_None: 465 // Okay 466 break; 467 468 case ASTContext::GE_Missing_stdio: 469 if (ForRedeclaration) 470 Diag(Loc, diag::err_implicit_decl_requires_stdio) 471 << Context.BuiltinInfo.GetName(BID); 472 return 0; 473 474 case ASTContext::GE_Missing_setjmp: 475 if (ForRedeclaration) 476 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 477 << Context.BuiltinInfo.GetName(BID); 478 return 0; 479 } 480 481 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 482 Diag(Loc, diag::ext_implicit_lib_function_decl) 483 << Context.BuiltinInfo.GetName(BID) 484 << R; 485 if (Context.BuiltinInfo.getHeaderName(BID) && 486 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 487 != Diagnostic::Ignored) 488 Diag(Loc, diag::note_please_include_header) 489 << Context.BuiltinInfo.getHeaderName(BID) 490 << Context.BuiltinInfo.GetName(BID); 491 } 492 493 FunctionDecl *New = FunctionDecl::Create(Context, 494 Context.getTranslationUnitDecl(), 495 Loc, II, R, /*DInfo=*/0, 496 FunctionDecl::Extern, false, 497 /*hasPrototype=*/true); 498 New->setImplicit(); 499 500 // Create Decl objects for each parameter, adding them to the 501 // FunctionDecl. 502 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 503 llvm::SmallVector<ParmVarDecl*, 16> Params; 504 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 505 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 506 FT->getArgType(i), /*DInfo=*/0, 507 VarDecl::None, 0)); 508 New->setParams(Context, Params.data(), Params.size()); 509 } 510 511 AddKnownFunctionAttributes(New); 512 513 // TUScope is the translation-unit scope to insert this function into. 514 // FIXME: This is hideous. We need to teach PushOnScopeChains to 515 // relate Scopes to DeclContexts, and probably eliminate CurContext 516 // entirely, but we're not there yet. 517 DeclContext *SavedContext = CurContext; 518 CurContext = Context.getTranslationUnitDecl(); 519 PushOnScopeChains(New, TUScope); 520 CurContext = SavedContext; 521 return New; 522} 523 524/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 525/// same name and scope as a previous declaration 'Old'. Figure out 526/// how to resolve this situation, merging decls or emitting 527/// diagnostics as appropriate. If there was an error, set New to be invalid. 528/// 529void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 530 // If either decl is known invalid already, set the new one to be invalid and 531 // don't bother doing any merging checks. 532 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 533 return New->setInvalidDecl(); 534 535 // Allow multiple definitions for ObjC built-in typedefs. 536 // FIXME: Verify the underlying types are equivalent! 537 if (getLangOptions().ObjC1) { 538 const IdentifierInfo *TypeID = New->getIdentifier(); 539 switch (TypeID->getLength()) { 540 default: break; 541 case 2: 542 if (!TypeID->isStr("id")) 543 break; 544 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 545 // Install the built-in type for 'id', ignoring the current definition. 546 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 547 return; 548 case 5: 549 if (!TypeID->isStr("Class")) 550 break; 551 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 552 // Install the built-in type for 'Class', ignoring the current definition. 553 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 554 return; 555 case 3: 556 if (!TypeID->isStr("SEL")) 557 break; 558 Context.setObjCSelType(Context.getTypeDeclType(New)); 559 return; 560 case 8: 561 if (!TypeID->isStr("Protocol")) 562 break; 563 Context.setObjCProtoType(New->getUnderlyingType()); 564 return; 565 } 566 // Fall through - the typedef name was not a builtin type. 567 } 568 // Verify the old decl was also a type. 569 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 570 if (!Old) { 571 Diag(New->getLocation(), diag::err_redefinition_different_kind) 572 << New->getDeclName(); 573 if (OldD->getLocation().isValid()) 574 Diag(OldD->getLocation(), diag::note_previous_definition); 575 return New->setInvalidDecl(); 576 } 577 578 // Determine the "old" type we'll use for checking and diagnostics. 579 QualType OldType; 580 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 581 OldType = OldTypedef->getUnderlyingType(); 582 else 583 OldType = Context.getTypeDeclType(Old); 584 585 // If the typedef types are not identical, reject them in all languages and 586 // with any extensions enabled. 587 588 if (OldType != New->getUnderlyingType() && 589 Context.getCanonicalType(OldType) != 590 Context.getCanonicalType(New->getUnderlyingType())) { 591 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 592 << New->getUnderlyingType() << OldType; 593 if (Old->getLocation().isValid()) 594 Diag(Old->getLocation(), diag::note_previous_definition); 595 return New->setInvalidDecl(); 596 } 597 598 if (getLangOptions().Microsoft) 599 return; 600 601 // C++ [dcl.typedef]p2: 602 // In a given non-class scope, a typedef specifier can be used to 603 // redefine the name of any type declared in that scope to refer 604 // to the type to which it already refers. 605 if (getLangOptions().CPlusPlus) { 606 if (!isa<CXXRecordDecl>(CurContext)) 607 return; 608 Diag(New->getLocation(), diag::err_redefinition) 609 << New->getDeclName(); 610 Diag(Old->getLocation(), diag::note_previous_definition); 611 return New->setInvalidDecl(); 612 } 613 614 // If we have a redefinition of a typedef in C, emit a warning. This warning 615 // is normally mapped to an error, but can be controlled with 616 // -Wtypedef-redefinition. If either the original or the redefinition is 617 // in a system header, don't emit this for compatibility with GCC. 618 if (PP.getDiagnostics().getSuppressSystemWarnings() && 619 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 620 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 621 return; 622 623 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 624 << New->getDeclName(); 625 Diag(Old->getLocation(), diag::note_previous_definition); 626 return; 627} 628 629/// DeclhasAttr - returns true if decl Declaration already has the target 630/// attribute. 631static bool 632DeclHasAttr(const Decl *decl, const Attr *target) { 633 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 634 if (attr->getKind() == target->getKind()) 635 return true; 636 637 return false; 638} 639 640/// MergeAttributes - append attributes from the Old decl to the New one. 641static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 642 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 643 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 644 Attr *NewAttr = attr->clone(C); 645 NewAttr->setInherited(true); 646 New->addAttr(NewAttr); 647 } 648 } 649} 650 651/// Used in MergeFunctionDecl to keep track of function parameters in 652/// C. 653struct GNUCompatibleParamWarning { 654 ParmVarDecl *OldParm; 655 ParmVarDecl *NewParm; 656 QualType PromotedType; 657}; 658 659/// MergeFunctionDecl - We just parsed a function 'New' from 660/// declarator D which has the same name and scope as a previous 661/// declaration 'Old'. Figure out how to resolve this situation, 662/// merging decls or emitting diagnostics as appropriate. 663/// 664/// In C++, New and Old must be declarations that are not 665/// overloaded. Use IsOverload to determine whether New and Old are 666/// overloaded, and to select the Old declaration that New should be 667/// merged with. 668/// 669/// Returns true if there was an error, false otherwise. 670bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 671 assert(!isa<OverloadedFunctionDecl>(OldD) && 672 "Cannot merge with an overloaded function declaration"); 673 674 // Verify the old decl was also a function. 675 FunctionDecl *Old = 0; 676 if (FunctionTemplateDecl *OldFunctionTemplate 677 = dyn_cast<FunctionTemplateDecl>(OldD)) 678 Old = OldFunctionTemplate->getTemplatedDecl(); 679 else 680 Old = dyn_cast<FunctionDecl>(OldD); 681 if (!Old) { 682 Diag(New->getLocation(), diag::err_redefinition_different_kind) 683 << New->getDeclName(); 684 Diag(OldD->getLocation(), diag::note_previous_definition); 685 return true; 686 } 687 688 // Determine whether the previous declaration was a definition, 689 // implicit declaration, or a declaration. 690 diag::kind PrevDiag; 691 if (Old->isThisDeclarationADefinition()) 692 PrevDiag = diag::note_previous_definition; 693 else if (Old->isImplicit()) 694 PrevDiag = diag::note_previous_implicit_declaration; 695 else 696 PrevDiag = diag::note_previous_declaration; 697 698 QualType OldQType = Context.getCanonicalType(Old->getType()); 699 QualType NewQType = Context.getCanonicalType(New->getType()); 700 701 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 702 New->getStorageClass() == FunctionDecl::Static && 703 Old->getStorageClass() != FunctionDecl::Static) { 704 Diag(New->getLocation(), diag::err_static_non_static) 705 << New; 706 Diag(Old->getLocation(), PrevDiag); 707 return true; 708 } 709 710 if (getLangOptions().CPlusPlus) { 711 // (C++98 13.1p2): 712 // Certain function declarations cannot be overloaded: 713 // -- Function declarations that differ only in the return type 714 // cannot be overloaded. 715 QualType OldReturnType 716 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 717 QualType NewReturnType 718 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 719 if (OldReturnType != NewReturnType) { 720 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 721 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 722 return true; 723 } 724 725 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 726 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 727 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 728 NewMethod->getLexicalDeclContext()->isRecord()) { 729 // -- Member function declarations with the same name and the 730 // same parameter types cannot be overloaded if any of them 731 // is a static member function declaration. 732 if (OldMethod->isStatic() || NewMethod->isStatic()) { 733 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 734 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 735 return true; 736 } 737 738 // C++ [class.mem]p1: 739 // [...] A member shall not be declared twice in the 740 // member-specification, except that a nested class or member 741 // class template can be declared and then later defined. 742 unsigned NewDiag; 743 if (isa<CXXConstructorDecl>(OldMethod)) 744 NewDiag = diag::err_constructor_redeclared; 745 else if (isa<CXXDestructorDecl>(NewMethod)) 746 NewDiag = diag::err_destructor_redeclared; 747 else if (isa<CXXConversionDecl>(NewMethod)) 748 NewDiag = diag::err_conv_function_redeclared; 749 else 750 NewDiag = diag::err_member_redeclared; 751 752 Diag(New->getLocation(), NewDiag); 753 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 754 } 755 756 // (C++98 8.3.5p3): 757 // All declarations for a function shall agree exactly in both the 758 // return type and the parameter-type-list. 759 if (OldQType == NewQType) 760 return MergeCompatibleFunctionDecls(New, Old); 761 762 // Fall through for conflicting redeclarations and redefinitions. 763 } 764 765 // C: Function types need to be compatible, not identical. This handles 766 // duplicate function decls like "void f(int); void f(enum X);" properly. 767 if (!getLangOptions().CPlusPlus && 768 Context.typesAreCompatible(OldQType, NewQType)) { 769 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 770 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 771 const FunctionProtoType *OldProto = 0; 772 if (isa<FunctionNoProtoType>(NewFuncType) && 773 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 774 // The old declaration provided a function prototype, but the 775 // new declaration does not. Merge in the prototype. 776 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 777 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 778 OldProto->arg_type_end()); 779 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 780 ParamTypes.data(), ParamTypes.size(), 781 OldProto->isVariadic(), 782 OldProto->getTypeQuals()); 783 New->setType(NewQType); 784 New->setHasInheritedPrototype(); 785 786 // Synthesize a parameter for each argument type. 787 llvm::SmallVector<ParmVarDecl*, 16> Params; 788 for (FunctionProtoType::arg_type_iterator 789 ParamType = OldProto->arg_type_begin(), 790 ParamEnd = OldProto->arg_type_end(); 791 ParamType != ParamEnd; ++ParamType) { 792 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 793 SourceLocation(), 0, 794 *ParamType, /*DInfo=*/0, 795 VarDecl::None, 0); 796 Param->setImplicit(); 797 Params.push_back(Param); 798 } 799 800 New->setParams(Context, Params.data(), Params.size()); 801 } 802 803 return MergeCompatibleFunctionDecls(New, Old); 804 } 805 806 // GNU C permits a K&R definition to follow a prototype declaration 807 // if the declared types of the parameters in the K&R definition 808 // match the types in the prototype declaration, even when the 809 // promoted types of the parameters from the K&R definition differ 810 // from the types in the prototype. GCC then keeps the types from 811 // the prototype. 812 // 813 // If a variadic prototype is followed by a non-variadic K&R definition, 814 // the K&R definition becomes variadic. This is sort of an edge case, but 815 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 816 // C99 6.9.1p8. 817 if (!getLangOptions().CPlusPlus && 818 Old->hasPrototype() && !New->hasPrototype() && 819 New->getType()->getAs<FunctionProtoType>() && 820 Old->getNumParams() == New->getNumParams()) { 821 llvm::SmallVector<QualType, 16> ArgTypes; 822 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 823 const FunctionProtoType *OldProto 824 = Old->getType()->getAs<FunctionProtoType>(); 825 const FunctionProtoType *NewProto 826 = New->getType()->getAs<FunctionProtoType>(); 827 828 // Determine whether this is the GNU C extension. 829 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 830 NewProto->getResultType()); 831 bool LooseCompatible = !MergedReturn.isNull(); 832 for (unsigned Idx = 0, End = Old->getNumParams(); 833 LooseCompatible && Idx != End; ++Idx) { 834 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 835 ParmVarDecl *NewParm = New->getParamDecl(Idx); 836 if (Context.typesAreCompatible(OldParm->getType(), 837 NewProto->getArgType(Idx))) { 838 ArgTypes.push_back(NewParm->getType()); 839 } else if (Context.typesAreCompatible(OldParm->getType(), 840 NewParm->getType())) { 841 GNUCompatibleParamWarning Warn 842 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 843 Warnings.push_back(Warn); 844 ArgTypes.push_back(NewParm->getType()); 845 } else 846 LooseCompatible = false; 847 } 848 849 if (LooseCompatible) { 850 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 851 Diag(Warnings[Warn].NewParm->getLocation(), 852 diag::ext_param_promoted_not_compatible_with_prototype) 853 << Warnings[Warn].PromotedType 854 << Warnings[Warn].OldParm->getType(); 855 Diag(Warnings[Warn].OldParm->getLocation(), 856 diag::note_previous_declaration); 857 } 858 859 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 860 ArgTypes.size(), 861 OldProto->isVariadic(), 0)); 862 return MergeCompatibleFunctionDecls(New, Old); 863 } 864 865 // Fall through to diagnose conflicting types. 866 } 867 868 // A function that has already been declared has been redeclared or defined 869 // with a different type- show appropriate diagnostic 870 if (unsigned BuiltinID = Old->getBuiltinID()) { 871 // The user has declared a builtin function with an incompatible 872 // signature. 873 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 874 // The function the user is redeclaring is a library-defined 875 // function like 'malloc' or 'printf'. Warn about the 876 // redeclaration, then pretend that we don't know about this 877 // library built-in. 878 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 879 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 880 << Old << Old->getType(); 881 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 882 Old->setInvalidDecl(); 883 return false; 884 } 885 886 PrevDiag = diag::note_previous_builtin_declaration; 887 } 888 889 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 890 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 891 return true; 892} 893 894/// \brief Completes the merge of two function declarations that are 895/// known to be compatible. 896/// 897/// This routine handles the merging of attributes and other 898/// properties of function declarations form the old declaration to 899/// the new declaration, once we know that New is in fact a 900/// redeclaration of Old. 901/// 902/// \returns false 903bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 904 // Merge the attributes 905 MergeAttributes(New, Old, Context); 906 907 // Merge the storage class. 908 if (Old->getStorageClass() != FunctionDecl::Extern && 909 Old->getStorageClass() != FunctionDecl::None) 910 New->setStorageClass(Old->getStorageClass()); 911 912 // Merge "pure" flag. 913 if (Old->isPure()) 914 New->setPure(); 915 916 // Merge the "deleted" flag. 917 if (Old->isDeleted()) 918 New->setDeleted(); 919 920 if (getLangOptions().CPlusPlus) 921 return MergeCXXFunctionDecl(New, Old); 922 923 return false; 924} 925 926/// MergeVarDecl - We just parsed a variable 'New' which has the same name 927/// and scope as a previous declaration 'Old'. Figure out how to resolve this 928/// situation, merging decls or emitting diagnostics as appropriate. 929/// 930/// Tentative definition rules (C99 6.9.2p2) are checked by 931/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 932/// definitions here, since the initializer hasn't been attached. 933/// 934void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 935 // If either decl is invalid, make sure the new one is marked invalid and 936 // don't do any other checking. 937 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 938 return New->setInvalidDecl(); 939 940 // Verify the old decl was also a variable. 941 VarDecl *Old = dyn_cast<VarDecl>(OldD); 942 if (!Old) { 943 Diag(New->getLocation(), diag::err_redefinition_different_kind) 944 << New->getDeclName(); 945 Diag(OldD->getLocation(), diag::note_previous_definition); 946 return New->setInvalidDecl(); 947 } 948 949 MergeAttributes(New, Old, Context); 950 951 // Merge the types 952 QualType MergedT; 953 if (getLangOptions().CPlusPlus) { 954 if (Context.hasSameType(New->getType(), Old->getType())) 955 MergedT = New->getType(); 956 // C++ [basic.types]p7: 957 // [...] The declared type of an array object might be an array of 958 // unknown size and therefore be incomplete at one point in a 959 // translation unit and complete later on; [...] 960 else if (Old->getType()->isIncompleteArrayType() && 961 New->getType()->isArrayType()) { 962 CanQual<ArrayType> OldArray 963 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 964 CanQual<ArrayType> NewArray 965 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 966 if (OldArray->getElementType() == NewArray->getElementType()) 967 MergedT = New->getType(); 968 } 969 } else { 970 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 971 } 972 if (MergedT.isNull()) { 973 Diag(New->getLocation(), diag::err_redefinition_different_type) 974 << New->getDeclName(); 975 Diag(Old->getLocation(), diag::note_previous_definition); 976 return New->setInvalidDecl(); 977 } 978 New->setType(MergedT); 979 980 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 981 if (New->getStorageClass() == VarDecl::Static && 982 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 983 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 984 Diag(Old->getLocation(), diag::note_previous_definition); 985 return New->setInvalidDecl(); 986 } 987 // C99 6.2.2p4: 988 // For an identifier declared with the storage-class specifier 989 // extern in a scope in which a prior declaration of that 990 // identifier is visible,23) if the prior declaration specifies 991 // internal or external linkage, the linkage of the identifier at 992 // the later declaration is the same as the linkage specified at 993 // the prior declaration. If no prior declaration is visible, or 994 // if the prior declaration specifies no linkage, then the 995 // identifier has external linkage. 996 if (New->hasExternalStorage() && Old->hasLinkage()) 997 /* Okay */; 998 else if (New->getStorageClass() != VarDecl::Static && 999 Old->getStorageClass() == VarDecl::Static) { 1000 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1001 Diag(Old->getLocation(), diag::note_previous_definition); 1002 return New->setInvalidDecl(); 1003 } 1004 1005 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1006 1007 // FIXME: The test for external storage here seems wrong? We still 1008 // need to check for mismatches. 1009 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1010 // Don't complain about out-of-line definitions of static members. 1011 !(Old->getLexicalDeclContext()->isRecord() && 1012 !New->getLexicalDeclContext()->isRecord())) { 1013 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1014 Diag(Old->getLocation(), diag::note_previous_definition); 1015 return New->setInvalidDecl(); 1016 } 1017 1018 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1019 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1020 Diag(Old->getLocation(), diag::note_previous_definition); 1021 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1022 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1023 Diag(Old->getLocation(), diag::note_previous_definition); 1024 } 1025 1026 // Keep a chain of previous declarations. 1027 New->setPreviousDeclaration(Old); 1028} 1029 1030/// CheckFallThrough - Check that we don't fall off the end of a 1031/// Statement that should return a value. 1032/// 1033/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1034/// MaybeFallThrough iff we might or might not fall off the end and 1035/// NeverFallThrough iff we never fall off the end of the statement. We assume 1036/// that functions not marked noreturn will return. 1037Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1038 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1039 1040 // FIXME: They should never return 0, fix that, delete this code. 1041 if (cfg == 0) 1042 return NeverFallThrough; 1043 // The CFG leaves in dead things, and we don't want to dead code paths to 1044 // confuse us, so we mark all live things first. 1045 std::queue<CFGBlock*> workq; 1046 llvm::BitVector live(cfg->getNumBlockIDs()); 1047 // Prep work queue 1048 workq.push(&cfg->getEntry()); 1049 // Solve 1050 while (!workq.empty()) { 1051 CFGBlock *item = workq.front(); 1052 workq.pop(); 1053 live.set(item->getBlockID()); 1054 for (CFGBlock::succ_iterator I=item->succ_begin(), 1055 E=item->succ_end(); 1056 I != E; 1057 ++I) { 1058 if ((*I) && !live[(*I)->getBlockID()]) { 1059 live.set((*I)->getBlockID()); 1060 workq.push(*I); 1061 } 1062 } 1063 } 1064 1065 // Now we know what is live, we check the live precessors of the exit block 1066 // and look for fall through paths, being careful to ignore normal returns, 1067 // and exceptional paths. 1068 bool HasLiveReturn = false; 1069 bool HasFakeEdge = false; 1070 bool HasPlainEdge = false; 1071 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1072 E = cfg->getExit().pred_end(); 1073 I != E; 1074 ++I) { 1075 CFGBlock& B = **I; 1076 if (!live[B.getBlockID()]) 1077 continue; 1078 if (B.size() == 0) { 1079 // A labeled empty statement, or the entry block... 1080 HasPlainEdge = true; 1081 continue; 1082 } 1083 Stmt *S = B[B.size()-1]; 1084 if (isa<ReturnStmt>(S)) { 1085 HasLiveReturn = true; 1086 continue; 1087 } 1088 if (isa<ObjCAtThrowStmt>(S)) { 1089 HasFakeEdge = true; 1090 continue; 1091 } 1092 if (isa<CXXThrowExpr>(S)) { 1093 HasFakeEdge = true; 1094 continue; 1095 } 1096 bool NoReturnEdge = false; 1097 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1098 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1099 if (CEE->getType().getNoReturnAttr()) { 1100 NoReturnEdge = true; 1101 HasFakeEdge = true; 1102 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1103 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1104 if (FD->hasAttr<NoReturnAttr>()) { 1105 NoReturnEdge = true; 1106 HasFakeEdge = true; 1107 } 1108 } 1109 } 1110 } 1111 // FIXME: Add noreturn message sends. 1112 if (NoReturnEdge == false) 1113 HasPlainEdge = true; 1114 } 1115 if (!HasPlainEdge) 1116 return NeverFallThrough; 1117 if (HasFakeEdge || HasLiveReturn) 1118 return MaybeFallThrough; 1119 // This says AlwaysFallThrough for calls to functions that are not marked 1120 // noreturn, that don't return. If people would like this warning to be more 1121 // accurate, such functions should be marked as noreturn. 1122 return AlwaysFallThrough; 1123} 1124 1125/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1126/// function that should return a value. Check that we don't fall off the end 1127/// of a noreturn function. We assume that functions and blocks not marked 1128/// noreturn will return. 1129void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1130 // FIXME: Would be nice if we had a better way to control cascading errors, 1131 // but for now, avoid them. The problem is that when Parse sees: 1132 // int foo() { return a; } 1133 // The return is eaten and the Sema code sees just: 1134 // int foo() { } 1135 // which this code would then warn about. 1136 if (getDiagnostics().hasErrorOccurred()) 1137 return; 1138 bool ReturnsVoid = false; 1139 bool HasNoReturn = false; 1140 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1141 if (FD->getResultType()->isVoidType()) 1142 ReturnsVoid = true; 1143 if (FD->hasAttr<NoReturnAttr>()) 1144 HasNoReturn = true; 1145 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1146 if (MD->getResultType()->isVoidType()) 1147 ReturnsVoid = true; 1148 if (MD->hasAttr<NoReturnAttr>()) 1149 HasNoReturn = true; 1150 } 1151 1152 // Short circuit for compilation speed. 1153 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1154 == Diagnostic::Ignored || ReturnsVoid) 1155 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1156 == Diagnostic::Ignored || !HasNoReturn) 1157 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1158 == Diagnostic::Ignored || !ReturnsVoid)) 1159 return; 1160 // FIXME: Funtion try block 1161 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1162 switch (CheckFallThrough(Body)) { 1163 case MaybeFallThrough: 1164 if (HasNoReturn) 1165 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1166 else if (!ReturnsVoid) 1167 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1168 break; 1169 case AlwaysFallThrough: 1170 if (HasNoReturn) 1171 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1172 else if (!ReturnsVoid) 1173 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1174 break; 1175 case NeverFallThrough: 1176 if (ReturnsVoid) 1177 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1178 break; 1179 } 1180 } 1181} 1182 1183/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1184/// that should return a value. Check that we don't fall off the end of a 1185/// noreturn block. We assume that functions and blocks not marked noreturn 1186/// will return. 1187void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1188 // FIXME: Would be nice if we had a better way to control cascading errors, 1189 // but for now, avoid them. The problem is that when Parse sees: 1190 // int foo() { return a; } 1191 // The return is eaten and the Sema code sees just: 1192 // int foo() { } 1193 // which this code would then warn about. 1194 if (getDiagnostics().hasErrorOccurred()) 1195 return; 1196 bool ReturnsVoid = false; 1197 bool HasNoReturn = false; 1198 if (const FunctionType *FT = BlockTy->getPointeeType()->getAs<FunctionType>()) { 1199 if (FT->getResultType()->isVoidType()) 1200 ReturnsVoid = true; 1201 if (FT->getNoReturnAttr()) 1202 HasNoReturn = true; 1203 } 1204 1205 // Short circuit for compilation speed. 1206 if (ReturnsVoid 1207 && !HasNoReturn 1208 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1209 == Diagnostic::Ignored || !ReturnsVoid)) 1210 return; 1211 // FIXME: Funtion try block 1212 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1213 switch (CheckFallThrough(Body)) { 1214 case MaybeFallThrough: 1215 if (HasNoReturn) 1216 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1217 else if (!ReturnsVoid) 1218 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1219 break; 1220 case AlwaysFallThrough: 1221 if (HasNoReturn) 1222 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1223 else if (!ReturnsVoid) 1224 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1225 break; 1226 case NeverFallThrough: 1227 if (ReturnsVoid) 1228 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1229 break; 1230 } 1231 } 1232} 1233 1234/// CheckParmsForFunctionDef - Check that the parameters of the given 1235/// function are appropriate for the definition of a function. This 1236/// takes care of any checks that cannot be performed on the 1237/// declaration itself, e.g., that the types of each of the function 1238/// parameters are complete. 1239bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1240 bool HasInvalidParm = false; 1241 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1242 ParmVarDecl *Param = FD->getParamDecl(p); 1243 1244 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1245 // function declarator that is part of a function definition of 1246 // that function shall not have incomplete type. 1247 // 1248 // This is also C++ [dcl.fct]p6. 1249 if (!Param->isInvalidDecl() && 1250 RequireCompleteType(Param->getLocation(), Param->getType(), 1251 diag::err_typecheck_decl_incomplete_type)) { 1252 Param->setInvalidDecl(); 1253 HasInvalidParm = true; 1254 } 1255 1256 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1257 // declaration of each parameter shall include an identifier. 1258 if (Param->getIdentifier() == 0 && 1259 !Param->isImplicit() && 1260 !getLangOptions().CPlusPlus) 1261 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1262 } 1263 1264 return HasInvalidParm; 1265} 1266 1267/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1268/// no declarator (e.g. "struct foo;") is parsed. 1269Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1270 // FIXME: Error on auto/register at file scope 1271 // FIXME: Error on inline/virtual/explicit 1272 // FIXME: Error on invalid restrict 1273 // FIXME: Warn on useless __thread 1274 // FIXME: Warn on useless const/volatile 1275 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1276 // FIXME: Warn on useless attributes 1277 TagDecl *Tag = 0; 1278 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1279 DS.getTypeSpecType() == DeclSpec::TST_struct || 1280 DS.getTypeSpecType() == DeclSpec::TST_union || 1281 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1282 if (!DS.getTypeRep()) // We probably had an error 1283 return DeclPtrTy(); 1284 1285 // Note that the above type specs guarantee that the 1286 // type rep is a Decl, whereas in many of the others 1287 // it's a Type. 1288 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1289 } 1290 1291 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1292 if (!Record->getDeclName() && Record->isDefinition() && 1293 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1294 if (getLangOptions().CPlusPlus || 1295 Record->getDeclContext()->isRecord()) 1296 return BuildAnonymousStructOrUnion(S, DS, Record); 1297 1298 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1299 << DS.getSourceRange(); 1300 } 1301 1302 // Microsoft allows unnamed struct/union fields. Don't complain 1303 // about them. 1304 // FIXME: Should we support Microsoft's extensions in this area? 1305 if (Record->getDeclName() && getLangOptions().Microsoft) 1306 return DeclPtrTy::make(Tag); 1307 } 1308 1309 if (!DS.isMissingDeclaratorOk() && 1310 DS.getTypeSpecType() != DeclSpec::TST_error) { 1311 // Warn about typedefs of enums without names, since this is an 1312 // extension in both Microsoft an GNU. 1313 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1314 Tag && isa<EnumDecl>(Tag)) { 1315 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1316 << DS.getSourceRange(); 1317 return DeclPtrTy::make(Tag); 1318 } 1319 1320 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1321 << DS.getSourceRange(); 1322 return DeclPtrTy(); 1323 } 1324 1325 return DeclPtrTy::make(Tag); 1326} 1327 1328/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1329/// anonymous struct or union AnonRecord into the owning context Owner 1330/// and scope S. This routine will be invoked just after we realize 1331/// that an unnamed union or struct is actually an anonymous union or 1332/// struct, e.g., 1333/// 1334/// @code 1335/// union { 1336/// int i; 1337/// float f; 1338/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1339/// // f into the surrounding scope.x 1340/// @endcode 1341/// 1342/// This routine is recursive, injecting the names of nested anonymous 1343/// structs/unions into the owning context and scope as well. 1344bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1345 RecordDecl *AnonRecord) { 1346 bool Invalid = false; 1347 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1348 FEnd = AnonRecord->field_end(); 1349 F != FEnd; ++F) { 1350 if ((*F)->getDeclName()) { 1351 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1352 LookupOrdinaryName, true); 1353 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1354 // C++ [class.union]p2: 1355 // The names of the members of an anonymous union shall be 1356 // distinct from the names of any other entity in the 1357 // scope in which the anonymous union is declared. 1358 unsigned diagKind 1359 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1360 : diag::err_anonymous_struct_member_redecl; 1361 Diag((*F)->getLocation(), diagKind) 1362 << (*F)->getDeclName(); 1363 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1364 Invalid = true; 1365 } else { 1366 // C++ [class.union]p2: 1367 // For the purpose of name lookup, after the anonymous union 1368 // definition, the members of the anonymous union are 1369 // considered to have been defined in the scope in which the 1370 // anonymous union is declared. 1371 Owner->makeDeclVisibleInContext(*F); 1372 S->AddDecl(DeclPtrTy::make(*F)); 1373 IdResolver.AddDecl(*F); 1374 } 1375 } else if (const RecordType *InnerRecordType 1376 = (*F)->getType()->getAs<RecordType>()) { 1377 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1378 if (InnerRecord->isAnonymousStructOrUnion()) 1379 Invalid = Invalid || 1380 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1381 } 1382 } 1383 1384 return Invalid; 1385} 1386 1387/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1388/// anonymous structure or union. Anonymous unions are a C++ feature 1389/// (C++ [class.union]) and a GNU C extension; anonymous structures 1390/// are a GNU C and GNU C++ extension. 1391Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1392 RecordDecl *Record) { 1393 DeclContext *Owner = Record->getDeclContext(); 1394 1395 // Diagnose whether this anonymous struct/union is an extension. 1396 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1397 Diag(Record->getLocation(), diag::ext_anonymous_union); 1398 else if (!Record->isUnion()) 1399 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1400 1401 // C and C++ require different kinds of checks for anonymous 1402 // structs/unions. 1403 bool Invalid = false; 1404 if (getLangOptions().CPlusPlus) { 1405 const char* PrevSpec = 0; 1406 unsigned DiagID; 1407 // C++ [class.union]p3: 1408 // Anonymous unions declared in a named namespace or in the 1409 // global namespace shall be declared static. 1410 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1411 (isa<TranslationUnitDecl>(Owner) || 1412 (isa<NamespaceDecl>(Owner) && 1413 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1414 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1415 Invalid = true; 1416 1417 // Recover by adding 'static'. 1418 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1419 PrevSpec, DiagID); 1420 } 1421 // C++ [class.union]p3: 1422 // A storage class is not allowed in a declaration of an 1423 // anonymous union in a class scope. 1424 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1425 isa<RecordDecl>(Owner)) { 1426 Diag(DS.getStorageClassSpecLoc(), 1427 diag::err_anonymous_union_with_storage_spec); 1428 Invalid = true; 1429 1430 // Recover by removing the storage specifier. 1431 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1432 PrevSpec, DiagID); 1433 } 1434 1435 // C++ [class.union]p2: 1436 // The member-specification of an anonymous union shall only 1437 // define non-static data members. [Note: nested types and 1438 // functions cannot be declared within an anonymous union. ] 1439 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1440 MemEnd = Record->decls_end(); 1441 Mem != MemEnd; ++Mem) { 1442 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1443 // C++ [class.union]p3: 1444 // An anonymous union shall not have private or protected 1445 // members (clause 11). 1446 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1447 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1448 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1449 Invalid = true; 1450 } 1451 } else if ((*Mem)->isImplicit()) { 1452 // Any implicit members are fine. 1453 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1454 // This is a type that showed up in an 1455 // elaborated-type-specifier inside the anonymous struct or 1456 // union, but which actually declares a type outside of the 1457 // anonymous struct or union. It's okay. 1458 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1459 if (!MemRecord->isAnonymousStructOrUnion() && 1460 MemRecord->getDeclName()) { 1461 // This is a nested type declaration. 1462 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1463 << (int)Record->isUnion(); 1464 Invalid = true; 1465 } 1466 } else { 1467 // We have something that isn't a non-static data 1468 // member. Complain about it. 1469 unsigned DK = diag::err_anonymous_record_bad_member; 1470 if (isa<TypeDecl>(*Mem)) 1471 DK = diag::err_anonymous_record_with_type; 1472 else if (isa<FunctionDecl>(*Mem)) 1473 DK = diag::err_anonymous_record_with_function; 1474 else if (isa<VarDecl>(*Mem)) 1475 DK = diag::err_anonymous_record_with_static; 1476 Diag((*Mem)->getLocation(), DK) 1477 << (int)Record->isUnion(); 1478 Invalid = true; 1479 } 1480 } 1481 } 1482 1483 if (!Record->isUnion() && !Owner->isRecord()) { 1484 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1485 << (int)getLangOptions().CPlusPlus; 1486 Invalid = true; 1487 } 1488 1489 // Create a declaration for this anonymous struct/union. 1490 NamedDecl *Anon = 0; 1491 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1492 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1493 /*IdentifierInfo=*/0, 1494 Context.getTypeDeclType(Record), 1495 // FIXME: Type source info. 1496 /*DInfo=*/0, 1497 /*BitWidth=*/0, /*Mutable=*/false); 1498 Anon->setAccess(AS_public); 1499 if (getLangOptions().CPlusPlus) 1500 FieldCollector->Add(cast<FieldDecl>(Anon)); 1501 } else { 1502 VarDecl::StorageClass SC; 1503 switch (DS.getStorageClassSpec()) { 1504 default: assert(0 && "Unknown storage class!"); 1505 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1506 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1507 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1508 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1509 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1510 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1511 case DeclSpec::SCS_mutable: 1512 // mutable can only appear on non-static class members, so it's always 1513 // an error here 1514 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1515 Invalid = true; 1516 SC = VarDecl::None; 1517 break; 1518 } 1519 1520 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1521 /*IdentifierInfo=*/0, 1522 Context.getTypeDeclType(Record), 1523 // FIXME: Type source info. 1524 /*DInfo=*/0, 1525 SC); 1526 } 1527 Anon->setImplicit(); 1528 1529 // Add the anonymous struct/union object to the current 1530 // context. We'll be referencing this object when we refer to one of 1531 // its members. 1532 Owner->addDecl(Anon); 1533 1534 // Inject the members of the anonymous struct/union into the owning 1535 // context and into the identifier resolver chain for name lookup 1536 // purposes. 1537 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1538 Invalid = true; 1539 1540 // Mark this as an anonymous struct/union type. Note that we do not 1541 // do this until after we have already checked and injected the 1542 // members of this anonymous struct/union type, because otherwise 1543 // the members could be injected twice: once by DeclContext when it 1544 // builds its lookup table, and once by 1545 // InjectAnonymousStructOrUnionMembers. 1546 Record->setAnonymousStructOrUnion(true); 1547 1548 if (Invalid) 1549 Anon->setInvalidDecl(); 1550 1551 return DeclPtrTy::make(Anon); 1552} 1553 1554 1555/// GetNameForDeclarator - Determine the full declaration name for the 1556/// given Declarator. 1557DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1558 switch (D.getKind()) { 1559 case Declarator::DK_Abstract: 1560 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1561 return DeclarationName(); 1562 1563 case Declarator::DK_Normal: 1564 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1565 return DeclarationName(D.getIdentifier()); 1566 1567 case Declarator::DK_Constructor: { 1568 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1569 return Context.DeclarationNames.getCXXConstructorName( 1570 Context.getCanonicalType(Ty)); 1571 } 1572 1573 case Declarator::DK_Destructor: { 1574 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1575 return Context.DeclarationNames.getCXXDestructorName( 1576 Context.getCanonicalType(Ty)); 1577 } 1578 1579 case Declarator::DK_Conversion: { 1580 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1581 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1582 return Context.DeclarationNames.getCXXConversionFunctionName( 1583 Context.getCanonicalType(Ty)); 1584 } 1585 1586 case Declarator::DK_Operator: 1587 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1588 return Context.DeclarationNames.getCXXOperatorName( 1589 D.getOverloadedOperator()); 1590 } 1591 1592 assert(false && "Unknown name kind"); 1593 return DeclarationName(); 1594} 1595 1596/// isNearlyMatchingFunction - Determine whether the C++ functions 1597/// Declaration and Definition are "nearly" matching. This heuristic 1598/// is used to improve diagnostics in the case where an out-of-line 1599/// function definition doesn't match any declaration within 1600/// the class or namespace. 1601static bool isNearlyMatchingFunction(ASTContext &Context, 1602 FunctionDecl *Declaration, 1603 FunctionDecl *Definition) { 1604 if (Declaration->param_size() != Definition->param_size()) 1605 return false; 1606 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1607 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1608 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1609 1610 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1611 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1612 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1613 return false; 1614 } 1615 1616 return true; 1617} 1618 1619Sema::DeclPtrTy 1620Sema::HandleDeclarator(Scope *S, Declarator &D, 1621 MultiTemplateParamsArg TemplateParamLists, 1622 bool IsFunctionDefinition) { 1623 DeclarationName Name = GetNameForDeclarator(D); 1624 1625 // All of these full declarators require an identifier. If it doesn't have 1626 // one, the ParsedFreeStandingDeclSpec action should be used. 1627 if (!Name) { 1628 if (!D.isInvalidType()) // Reject this if we think it is valid. 1629 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1630 diag::err_declarator_need_ident) 1631 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1632 return DeclPtrTy(); 1633 } 1634 1635 // The scope passed in may not be a decl scope. Zip up the scope tree until 1636 // we find one that is. 1637 while ((S->getFlags() & Scope::DeclScope) == 0 || 1638 (S->getFlags() & Scope::TemplateParamScope) != 0) 1639 S = S->getParent(); 1640 1641 // If this is an out-of-line definition of a member of a class template 1642 // or class template partial specialization, we may need to rebuild the 1643 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1644 // for more information. 1645 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1646 // handle expressions properly. 1647 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1648 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1649 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1650 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1651 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1652 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1653 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1654 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1655 // FIXME: Preserve type source info. 1656 QualType T = GetTypeFromParser(DS.getTypeRep()); 1657 EnterDeclaratorContext(S, DC); 1658 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1659 ExitDeclaratorContext(S); 1660 if (T.isNull()) 1661 return DeclPtrTy(); 1662 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1663 } 1664 } 1665 1666 DeclContext *DC; 1667 NamedDecl *PrevDecl; 1668 NamedDecl *New; 1669 1670 DeclaratorInfo *DInfo = 0; 1671 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1672 1673 // See if this is a redefinition of a variable in the same scope. 1674 if (D.getCXXScopeSpec().isInvalid()) { 1675 DC = CurContext; 1676 PrevDecl = 0; 1677 D.setInvalidType(); 1678 } else if (!D.getCXXScopeSpec().isSet()) { 1679 LookupNameKind NameKind = LookupOrdinaryName; 1680 1681 // If the declaration we're planning to build will be a function 1682 // or object with linkage, then look for another declaration with 1683 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1684 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1685 /* Do nothing*/; 1686 else if (R->isFunctionType()) { 1687 if (CurContext->isFunctionOrMethod() || 1688 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1689 NameKind = LookupRedeclarationWithLinkage; 1690 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1691 NameKind = LookupRedeclarationWithLinkage; 1692 else if (CurContext->getLookupContext()->isTranslationUnit() && 1693 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1694 NameKind = LookupRedeclarationWithLinkage; 1695 1696 DC = CurContext; 1697 PrevDecl = LookupName(S, Name, NameKind, true, 1698 NameKind == LookupRedeclarationWithLinkage, 1699 D.getIdentifierLoc()); 1700 } else { // Something like "int foo::x;" 1701 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1702 1703 if (!DC) { 1704 // If we could not compute the declaration context, it's because the 1705 // declaration context is dependent but does not refer to a class, 1706 // class template, or class template partial specialization. Complain 1707 // and return early, to avoid the coming semantic disaster. 1708 Diag(D.getIdentifierLoc(), 1709 diag::err_template_qualified_declarator_no_match) 1710 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1711 << D.getCXXScopeSpec().getRange(); 1712 return DeclPtrTy(); 1713 } 1714 1715 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1716 1717 // C++ 7.3.1.2p2: 1718 // Members (including explicit specializations of templates) of a named 1719 // namespace can also be defined outside that namespace by explicit 1720 // qualification of the name being defined, provided that the entity being 1721 // defined was already declared in the namespace and the definition appears 1722 // after the point of declaration in a namespace that encloses the 1723 // declarations namespace. 1724 // 1725 // Note that we only check the context at this point. We don't yet 1726 // have enough information to make sure that PrevDecl is actually 1727 // the declaration we want to match. For example, given: 1728 // 1729 // class X { 1730 // void f(); 1731 // void f(float); 1732 // }; 1733 // 1734 // void X::f(int) { } // ill-formed 1735 // 1736 // In this case, PrevDecl will point to the overload set 1737 // containing the two f's declared in X, but neither of them 1738 // matches. 1739 1740 // First check whether we named the global scope. 1741 if (isa<TranslationUnitDecl>(DC)) { 1742 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1743 << Name << D.getCXXScopeSpec().getRange(); 1744 } else if (!CurContext->Encloses(DC)) { 1745 // The qualifying scope doesn't enclose the original declaration. 1746 // Emit diagnostic based on current scope. 1747 SourceLocation L = D.getIdentifierLoc(); 1748 SourceRange R = D.getCXXScopeSpec().getRange(); 1749 if (isa<FunctionDecl>(CurContext)) 1750 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1751 else 1752 Diag(L, diag::err_invalid_declarator_scope) 1753 << Name << cast<NamedDecl>(DC) << R; 1754 D.setInvalidType(); 1755 } 1756 } 1757 1758 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1759 // Maybe we will complain about the shadowed template parameter. 1760 if (!D.isInvalidType()) 1761 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1762 D.setInvalidType(); 1763 1764 // Just pretend that we didn't see the previous declaration. 1765 PrevDecl = 0; 1766 } 1767 1768 // In C++, the previous declaration we find might be a tag type 1769 // (class or enum). In this case, the new declaration will hide the 1770 // tag type. Note that this does does not apply if we're declaring a 1771 // typedef (C++ [dcl.typedef]p4). 1772 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1773 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1774 PrevDecl = 0; 1775 1776 bool Redeclaration = false; 1777 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1778 if (TemplateParamLists.size()) { 1779 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1780 return DeclPtrTy(); 1781 } 1782 1783 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1784 } else if (R->isFunctionType()) { 1785 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1786 move(TemplateParamLists), 1787 IsFunctionDefinition, Redeclaration); 1788 } else { 1789 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1790 move(TemplateParamLists), 1791 Redeclaration); 1792 } 1793 1794 if (New == 0) 1795 return DeclPtrTy(); 1796 1797 // If this has an identifier and is not an invalid redeclaration or 1798 // function template specialization, add it to the scope stack. 1799 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1800 !(isa<FunctionDecl>(New) && 1801 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1802 PushOnScopeChains(New, S); 1803 1804 return DeclPtrTy::make(New); 1805} 1806 1807/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1808/// types into constant array types in certain situations which would otherwise 1809/// be errors (for GCC compatibility). 1810static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1811 ASTContext &Context, 1812 bool &SizeIsNegative) { 1813 // This method tries to turn a variable array into a constant 1814 // array even when the size isn't an ICE. This is necessary 1815 // for compatibility with code that depends on gcc's buggy 1816 // constant expression folding, like struct {char x[(int)(char*)2];} 1817 SizeIsNegative = false; 1818 1819 QualifierCollector Qs; 1820 const Type *Ty = Qs.strip(T); 1821 1822 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1823 QualType Pointee = PTy->getPointeeType(); 1824 QualType FixedType = 1825 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1826 if (FixedType.isNull()) return FixedType; 1827 FixedType = Context.getPointerType(FixedType); 1828 return Qs.apply(FixedType); 1829 } 1830 1831 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1832 if (!VLATy) 1833 return QualType(); 1834 // FIXME: We should probably handle this case 1835 if (VLATy->getElementType()->isVariablyModifiedType()) 1836 return QualType(); 1837 1838 Expr::EvalResult EvalResult; 1839 if (!VLATy->getSizeExpr() || 1840 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1841 !EvalResult.Val.isInt()) 1842 return QualType(); 1843 1844 llvm::APSInt &Res = EvalResult.Val.getInt(); 1845 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1846 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1847 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1848 // so as to transfer ownership to the ConstantArrayWithExpr. 1849 // Alternatively, we could "clone" it (how?). 1850 // Since we don't know how to do things above, we just use the 1851 // very same Expr*. 1852 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1853 Res, ArySizeExpr, 1854 ArrayType::Normal, 0, 1855 VLATy->getBracketsRange()); 1856 } 1857 1858 SizeIsNegative = true; 1859 return QualType(); 1860} 1861 1862/// \brief Register the given locally-scoped external C declaration so 1863/// that it can be found later for redeclarations 1864void 1865Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1866 Scope *S) { 1867 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1868 "Decl is not a locally-scoped decl!"); 1869 // Note that we have a locally-scoped external with this name. 1870 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1871 1872 if (!PrevDecl) 1873 return; 1874 1875 // If there was a previous declaration of this variable, it may be 1876 // in our identifier chain. Update the identifier chain with the new 1877 // declaration. 1878 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1879 // The previous declaration was found on the identifer resolver 1880 // chain, so remove it from its scope. 1881 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1882 S = S->getParent(); 1883 1884 if (S) 1885 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1886 } 1887} 1888 1889/// \brief Diagnose function specifiers on a declaration of an identifier that 1890/// does not identify a function. 1891void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1892 // FIXME: We should probably indicate the identifier in question to avoid 1893 // confusion for constructs like "inline int a(), b;" 1894 if (D.getDeclSpec().isInlineSpecified()) 1895 Diag(D.getDeclSpec().getInlineSpecLoc(), 1896 diag::err_inline_non_function); 1897 1898 if (D.getDeclSpec().isVirtualSpecified()) 1899 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1900 diag::err_virtual_non_function); 1901 1902 if (D.getDeclSpec().isExplicitSpecified()) 1903 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1904 diag::err_explicit_non_function); 1905} 1906 1907NamedDecl* 1908Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1909 QualType R, DeclaratorInfo *DInfo, 1910 Decl* PrevDecl, bool &Redeclaration) { 1911 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1912 if (D.getCXXScopeSpec().isSet()) { 1913 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1914 << D.getCXXScopeSpec().getRange(); 1915 D.setInvalidType(); 1916 // Pretend we didn't see the scope specifier. 1917 DC = 0; 1918 } 1919 1920 if (getLangOptions().CPlusPlus) { 1921 // Check that there are no default arguments (C++ only). 1922 CheckExtraCXXDefaultArguments(D); 1923 } 1924 1925 DiagnoseFunctionSpecifiers(D); 1926 1927 if (D.getDeclSpec().isThreadSpecified()) 1928 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1929 1930 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1931 if (!NewTD) return 0; 1932 1933 if (D.isInvalidType()) 1934 NewTD->setInvalidDecl(); 1935 1936 // Handle attributes prior to checking for duplicates in MergeVarDecl 1937 ProcessDeclAttributes(S, NewTD, D); 1938 // Merge the decl with the existing one if appropriate. If the decl is 1939 // in an outer scope, it isn't the same thing. 1940 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1941 Redeclaration = true; 1942 MergeTypeDefDecl(NewTD, PrevDecl); 1943 } 1944 1945 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1946 // then it shall have block scope. 1947 QualType T = NewTD->getUnderlyingType(); 1948 if (T->isVariablyModifiedType()) { 1949 CurFunctionNeedsScopeChecking = true; 1950 1951 if (S->getFnParent() == 0) { 1952 bool SizeIsNegative; 1953 QualType FixedTy = 1954 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1955 if (!FixedTy.isNull()) { 1956 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1957 NewTD->setUnderlyingType(FixedTy); 1958 } else { 1959 if (SizeIsNegative) 1960 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1961 else if (T->isVariableArrayType()) 1962 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1963 else 1964 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1965 NewTD->setInvalidDecl(); 1966 } 1967 } 1968 } 1969 1970 // If this is the C FILE type, notify the AST context. 1971 if (IdentifierInfo *II = NewTD->getIdentifier()) 1972 if (!NewTD->isInvalidDecl() && 1973 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1974 if (II->isStr("FILE")) 1975 Context.setFILEDecl(NewTD); 1976 else if (II->isStr("jmp_buf")) 1977 Context.setjmp_bufDecl(NewTD); 1978 else if (II->isStr("sigjmp_buf")) 1979 Context.setsigjmp_bufDecl(NewTD); 1980 } 1981 1982 return NewTD; 1983} 1984 1985/// \brief Determines whether the given declaration is an out-of-scope 1986/// previous declaration. 1987/// 1988/// This routine should be invoked when name lookup has found a 1989/// previous declaration (PrevDecl) that is not in the scope where a 1990/// new declaration by the same name is being introduced. If the new 1991/// declaration occurs in a local scope, previous declarations with 1992/// linkage may still be considered previous declarations (C99 1993/// 6.2.2p4-5, C++ [basic.link]p6). 1994/// 1995/// \param PrevDecl the previous declaration found by name 1996/// lookup 1997/// 1998/// \param DC the context in which the new declaration is being 1999/// declared. 2000/// 2001/// \returns true if PrevDecl is an out-of-scope previous declaration 2002/// for a new delcaration with the same name. 2003static bool 2004isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2005 ASTContext &Context) { 2006 if (!PrevDecl) 2007 return 0; 2008 2009 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2010 // case we need to check each of the overloaded functions. 2011 if (!PrevDecl->hasLinkage()) 2012 return false; 2013 2014 if (Context.getLangOptions().CPlusPlus) { 2015 // C++ [basic.link]p6: 2016 // If there is a visible declaration of an entity with linkage 2017 // having the same name and type, ignoring entities declared 2018 // outside the innermost enclosing namespace scope, the block 2019 // scope declaration declares that same entity and receives the 2020 // linkage of the previous declaration. 2021 DeclContext *OuterContext = DC->getLookupContext(); 2022 if (!OuterContext->isFunctionOrMethod()) 2023 // This rule only applies to block-scope declarations. 2024 return false; 2025 else { 2026 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2027 if (PrevOuterContext->isRecord()) 2028 // We found a member function: ignore it. 2029 return false; 2030 else { 2031 // Find the innermost enclosing namespace for the new and 2032 // previous declarations. 2033 while (!OuterContext->isFileContext()) 2034 OuterContext = OuterContext->getParent(); 2035 while (!PrevOuterContext->isFileContext()) 2036 PrevOuterContext = PrevOuterContext->getParent(); 2037 2038 // The previous declaration is in a different namespace, so it 2039 // isn't the same function. 2040 if (OuterContext->getPrimaryContext() != 2041 PrevOuterContext->getPrimaryContext()) 2042 return false; 2043 } 2044 } 2045 } 2046 2047 return true; 2048} 2049 2050NamedDecl* 2051Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2052 QualType R, DeclaratorInfo *DInfo, 2053 NamedDecl* PrevDecl, 2054 MultiTemplateParamsArg TemplateParamLists, 2055 bool &Redeclaration) { 2056 DeclarationName Name = GetNameForDeclarator(D); 2057 2058 // Check that there are no default arguments (C++ only). 2059 if (getLangOptions().CPlusPlus) 2060 CheckExtraCXXDefaultArguments(D); 2061 2062 VarDecl *NewVD; 2063 VarDecl::StorageClass SC; 2064 switch (D.getDeclSpec().getStorageClassSpec()) { 2065 default: assert(0 && "Unknown storage class!"); 2066 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2067 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2068 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2069 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2070 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2071 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2072 case DeclSpec::SCS_mutable: 2073 // mutable can only appear on non-static class members, so it's always 2074 // an error here 2075 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2076 D.setInvalidType(); 2077 SC = VarDecl::None; 2078 break; 2079 } 2080 2081 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2082 if (!II) { 2083 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2084 << Name.getAsString(); 2085 return 0; 2086 } 2087 2088 DiagnoseFunctionSpecifiers(D); 2089 2090 if (!DC->isRecord() && S->getFnParent() == 0) { 2091 // C99 6.9p2: The storage-class specifiers auto and register shall not 2092 // appear in the declaration specifiers in an external declaration. 2093 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2094 2095 // If this is a register variable with an asm label specified, then this 2096 // is a GNU extension. 2097 if (SC == VarDecl::Register && D.getAsmLabel()) 2098 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2099 else 2100 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2101 D.setInvalidType(); 2102 } 2103 } 2104 if (DC->isRecord() && !CurContext->isRecord()) { 2105 // This is an out-of-line definition of a static data member. 2106 if (SC == VarDecl::Static) { 2107 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2108 diag::err_static_out_of_line) 2109 << CodeModificationHint::CreateRemoval( 2110 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2111 } else if (SC == VarDecl::None) 2112 SC = VarDecl::Static; 2113 } 2114 if (SC == VarDecl::Static) { 2115 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2116 if (RD->isLocalClass()) 2117 Diag(D.getIdentifierLoc(), 2118 diag::err_static_data_member_not_allowed_in_local_class) 2119 << Name << RD->getDeclName(); 2120 } 2121 } 2122 2123 // Match up the template parameter lists with the scope specifier, then 2124 // determine whether we have a template or a template specialization. 2125 if (TemplateParameterList *TemplateParams 2126 = MatchTemplateParametersToScopeSpecifier( 2127 D.getDeclSpec().getSourceRange().getBegin(), 2128 D.getCXXScopeSpec(), 2129 (TemplateParameterList**)TemplateParamLists.get(), 2130 TemplateParamLists.size())) { 2131 if (TemplateParams->size() > 0) { 2132 // There is no such thing as a variable template. 2133 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2134 << II 2135 << SourceRange(TemplateParams->getTemplateLoc(), 2136 TemplateParams->getRAngleLoc()); 2137 return 0; 2138 } else { 2139 // There is an extraneous 'template<>' for this variable. Complain 2140 // about it, but allow the declaration of the variable. 2141 Diag(TemplateParams->getTemplateLoc(), 2142 diag::err_template_variable_noparams) 2143 << II 2144 << SourceRange(TemplateParams->getTemplateLoc(), 2145 TemplateParams->getRAngleLoc()); 2146 } 2147 } 2148 2149 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2150 II, R, DInfo, SC); 2151 2152 if (D.isInvalidType()) 2153 NewVD->setInvalidDecl(); 2154 2155 if (D.getDeclSpec().isThreadSpecified()) { 2156 if (NewVD->hasLocalStorage()) 2157 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2158 else if (!Context.Target.isTLSSupported()) 2159 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2160 else 2161 NewVD->setThreadSpecified(true); 2162 } 2163 2164 // Set the lexical context. If the declarator has a C++ scope specifier, the 2165 // lexical context will be different from the semantic context. 2166 NewVD->setLexicalDeclContext(CurContext); 2167 2168 // Handle attributes prior to checking for duplicates in MergeVarDecl 2169 ProcessDeclAttributes(S, NewVD, D); 2170 2171 // Handle GNU asm-label extension (encoded as an attribute). 2172 if (Expr *E = (Expr*) D.getAsmLabel()) { 2173 // The parser guarantees this is a string. 2174 StringLiteral *SE = cast<StringLiteral>(E); 2175 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2176 SE->getByteLength()))); 2177 } 2178 2179 // If name lookup finds a previous declaration that is not in the 2180 // same scope as the new declaration, this may still be an 2181 // acceptable redeclaration. 2182 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2183 !(NewVD->hasLinkage() && 2184 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2185 PrevDecl = 0; 2186 2187 // Merge the decl with the existing one if appropriate. 2188 if (PrevDecl) { 2189 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2190 // The user tried to define a non-static data member 2191 // out-of-line (C++ [dcl.meaning]p1). 2192 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2193 << D.getCXXScopeSpec().getRange(); 2194 PrevDecl = 0; 2195 NewVD->setInvalidDecl(); 2196 } 2197 } else if (D.getCXXScopeSpec().isSet()) { 2198 // No previous declaration in the qualifying scope. 2199 NestedNameSpecifier *NNS = 2200 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2201 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2202 D.getCXXScopeSpec().getRange()); 2203 NewVD->setInvalidDecl(); 2204 } 2205 2206 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2207 2208 // attributes declared post-definition are currently ignored 2209 if (PrevDecl) { 2210 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2211 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2212 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2213 Diag(Def->getLocation(), diag::note_previous_definition); 2214 } 2215 } 2216 2217 // If this is a locally-scoped extern C variable, update the map of 2218 // such variables. 2219 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2220 !NewVD->isInvalidDecl()) 2221 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2222 2223 return NewVD; 2224} 2225 2226/// \brief Perform semantic checking on a newly-created variable 2227/// declaration. 2228/// 2229/// This routine performs all of the type-checking required for a 2230/// variable declaration once it has been built. It is used both to 2231/// check variables after they have been parsed and their declarators 2232/// have been translated into a declaration, and to check variables 2233/// that have been instantiated from a template. 2234/// 2235/// Sets NewVD->isInvalidDecl() if an error was encountered. 2236void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2237 bool &Redeclaration) { 2238 // If the decl is already known invalid, don't check it. 2239 if (NewVD->isInvalidDecl()) 2240 return; 2241 2242 QualType T = NewVD->getType(); 2243 2244 if (T->isObjCInterfaceType()) { 2245 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2246 return NewVD->setInvalidDecl(); 2247 } 2248 2249 // The variable can not have an abstract class type. 2250 if (RequireNonAbstractType(NewVD->getLocation(), T, 2251 diag::err_abstract_type_in_decl, 2252 AbstractVariableType)) 2253 return NewVD->setInvalidDecl(); 2254 2255 // Emit an error if an address space was applied to decl with local storage. 2256 // This includes arrays of objects with address space qualifiers, but not 2257 // automatic variables that point to other address spaces. 2258 // ISO/IEC TR 18037 S5.1.2 2259 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2260 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2261 return NewVD->setInvalidDecl(); 2262 } 2263 2264 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2265 && !NewVD->hasAttr<BlocksAttr>()) 2266 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2267 2268 bool isVM = T->isVariablyModifiedType(); 2269 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2270 NewVD->hasAttr<BlocksAttr>()) 2271 CurFunctionNeedsScopeChecking = true; 2272 2273 if ((isVM && NewVD->hasLinkage()) || 2274 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2275 bool SizeIsNegative; 2276 QualType FixedTy = 2277 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2278 2279 if (FixedTy.isNull() && T->isVariableArrayType()) { 2280 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2281 // FIXME: This won't give the correct result for 2282 // int a[10][n]; 2283 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2284 2285 if (NewVD->isFileVarDecl()) 2286 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2287 << SizeRange; 2288 else if (NewVD->getStorageClass() == VarDecl::Static) 2289 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2290 << SizeRange; 2291 else 2292 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2293 << SizeRange; 2294 return NewVD->setInvalidDecl(); 2295 } 2296 2297 if (FixedTy.isNull()) { 2298 if (NewVD->isFileVarDecl()) 2299 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2300 else 2301 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2302 return NewVD->setInvalidDecl(); 2303 } 2304 2305 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2306 NewVD->setType(FixedTy); 2307 } 2308 2309 if (!PrevDecl && NewVD->isExternC()) { 2310 // Since we did not find anything by this name and we're declaring 2311 // an extern "C" variable, look for a non-visible extern "C" 2312 // declaration with the same name. 2313 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2314 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2315 if (Pos != LocallyScopedExternalDecls.end()) 2316 PrevDecl = Pos->second; 2317 } 2318 2319 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2320 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2321 << T; 2322 return NewVD->setInvalidDecl(); 2323 } 2324 2325 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2326 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2327 return NewVD->setInvalidDecl(); 2328 } 2329 2330 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2331 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2332 return NewVD->setInvalidDecl(); 2333 } 2334 2335 if (PrevDecl) { 2336 Redeclaration = true; 2337 MergeVarDecl(NewVD, PrevDecl); 2338 } 2339} 2340 2341static bool isUsingDecl(Decl *D) { 2342 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2343} 2344 2345NamedDecl* 2346Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2347 QualType R, DeclaratorInfo *DInfo, 2348 NamedDecl* PrevDecl, 2349 MultiTemplateParamsArg TemplateParamLists, 2350 bool IsFunctionDefinition, bool &Redeclaration) { 2351 assert(R.getTypePtr()->isFunctionType()); 2352 2353 DeclarationName Name = GetNameForDeclarator(D); 2354 FunctionDecl::StorageClass SC = FunctionDecl::None; 2355 switch (D.getDeclSpec().getStorageClassSpec()) { 2356 default: assert(0 && "Unknown storage class!"); 2357 case DeclSpec::SCS_auto: 2358 case DeclSpec::SCS_register: 2359 case DeclSpec::SCS_mutable: 2360 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2361 diag::err_typecheck_sclass_func); 2362 D.setInvalidType(); 2363 break; 2364 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2365 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2366 case DeclSpec::SCS_static: { 2367 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2368 // C99 6.7.1p5: 2369 // The declaration of an identifier for a function that has 2370 // block scope shall have no explicit storage-class specifier 2371 // other than extern 2372 // See also (C++ [dcl.stc]p4). 2373 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2374 diag::err_static_block_func); 2375 SC = FunctionDecl::None; 2376 } else 2377 SC = FunctionDecl::Static; 2378 break; 2379 } 2380 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2381 } 2382 2383 if (D.getDeclSpec().isThreadSpecified()) 2384 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2385 2386 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2387 bool isInline = D.getDeclSpec().isInlineSpecified(); 2388 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2389 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2390 2391 // Check that the return type is not an abstract class type. 2392 // For record types, this is done by the AbstractClassUsageDiagnoser once 2393 // the class has been completely parsed. 2394 if (!DC->isRecord() && 2395 RequireNonAbstractType(D.getIdentifierLoc(), 2396 R->getAs<FunctionType>()->getResultType(), 2397 diag::err_abstract_type_in_decl, 2398 AbstractReturnType)) 2399 D.setInvalidType(); 2400 2401 // Do not allow returning a objc interface by-value. 2402 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2403 Diag(D.getIdentifierLoc(), 2404 diag::err_object_cannot_be_passed_returned_by_value) << 0 2405 << R->getAs<FunctionType>()->getResultType(); 2406 D.setInvalidType(); 2407 } 2408 2409 bool isVirtualOkay = false; 2410 FunctionDecl *NewFD; 2411 2412 if (isFriend) { 2413 // DC is the namespace in which the function is being declared. 2414 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2415 "friend function being created in a non-namespace context"); 2416 2417 // C++ [class.friend]p5 2418 // A function can be defined in a friend declaration of a 2419 // class . . . . Such a function is implicitly inline. 2420 isInline |= IsFunctionDefinition; 2421 } 2422 2423 if (D.getKind() == Declarator::DK_Constructor) { 2424 // This is a C++ constructor declaration. 2425 assert(DC->isRecord() && 2426 "Constructors can only be declared in a member context"); 2427 2428 R = CheckConstructorDeclarator(D, R, SC); 2429 2430 // Create the new declaration 2431 NewFD = CXXConstructorDecl::Create(Context, 2432 cast<CXXRecordDecl>(DC), 2433 D.getIdentifierLoc(), Name, R, DInfo, 2434 isExplicit, isInline, 2435 /*isImplicitlyDeclared=*/false); 2436 } else if (D.getKind() == Declarator::DK_Destructor) { 2437 // This is a C++ destructor declaration. 2438 if (DC->isRecord()) { 2439 R = CheckDestructorDeclarator(D, SC); 2440 2441 NewFD = CXXDestructorDecl::Create(Context, 2442 cast<CXXRecordDecl>(DC), 2443 D.getIdentifierLoc(), Name, R, 2444 isInline, 2445 /*isImplicitlyDeclared=*/false); 2446 2447 isVirtualOkay = true; 2448 } else { 2449 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2450 2451 // Create a FunctionDecl to satisfy the function definition parsing 2452 // code path. 2453 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2454 Name, R, DInfo, SC, isInline, 2455 /*hasPrototype=*/true); 2456 D.setInvalidType(); 2457 } 2458 } else if (D.getKind() == Declarator::DK_Conversion) { 2459 if (!DC->isRecord()) { 2460 Diag(D.getIdentifierLoc(), 2461 diag::err_conv_function_not_member); 2462 return 0; 2463 } 2464 2465 CheckConversionDeclarator(D, R, SC); 2466 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2467 D.getIdentifierLoc(), Name, R, DInfo, 2468 isInline, isExplicit); 2469 2470 isVirtualOkay = true; 2471 } else if (DC->isRecord()) { 2472 // If the of the function is the same as the name of the record, then this 2473 // must be an invalid constructor that has a return type. 2474 // (The parser checks for a return type and makes the declarator a 2475 // constructor if it has no return type). 2476 // must have an invalid constructor that has a return type 2477 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2478 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2479 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2480 << SourceRange(D.getIdentifierLoc()); 2481 return 0; 2482 } 2483 2484 // This is a C++ method declaration. 2485 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2486 D.getIdentifierLoc(), Name, R, DInfo, 2487 (SC == FunctionDecl::Static), isInline); 2488 2489 isVirtualOkay = (SC != FunctionDecl::Static); 2490 } else { 2491 // Determine whether the function was written with a 2492 // prototype. This true when: 2493 // - we're in C++ (where every function has a prototype), 2494 // - there is a prototype in the declarator, or 2495 // - the type R of the function is some kind of typedef or other reference 2496 // to a type name (which eventually refers to a function type). 2497 bool HasPrototype = 2498 getLangOptions().CPlusPlus || 2499 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2500 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2501 2502 NewFD = FunctionDecl::Create(Context, DC, 2503 D.getIdentifierLoc(), 2504 Name, R, DInfo, SC, isInline, HasPrototype); 2505 } 2506 2507 if (D.isInvalidType()) 2508 NewFD->setInvalidDecl(); 2509 2510 // Set the lexical context. If the declarator has a C++ 2511 // scope specifier, or is the object of a friend declaration, the 2512 // lexical context will be different from the semantic context. 2513 NewFD->setLexicalDeclContext(CurContext); 2514 2515 if (isFriend) 2516 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2517 2518 // Match up the template parameter lists with the scope specifier, then 2519 // determine whether we have a template or a template specialization. 2520 FunctionTemplateDecl *FunctionTemplate = 0; 2521 bool isFunctionTemplateSpecialization = false; 2522 if (TemplateParameterList *TemplateParams 2523 = MatchTemplateParametersToScopeSpecifier( 2524 D.getDeclSpec().getSourceRange().getBegin(), 2525 D.getCXXScopeSpec(), 2526 (TemplateParameterList**)TemplateParamLists.get(), 2527 TemplateParamLists.size())) { 2528 if (TemplateParams->size() > 0) { 2529 // This is a function template 2530 2531 // Check that we can declare a template here. 2532 if (CheckTemplateDeclScope(S, TemplateParams)) 2533 return 0; 2534 2535 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2536 NewFD->getLocation(), 2537 Name, TemplateParams, 2538 NewFD); 2539 FunctionTemplate->setLexicalDeclContext(CurContext); 2540 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2541 } else { 2542 // This is a function template specialization. 2543 isFunctionTemplateSpecialization = true; 2544 } 2545 2546 // FIXME: Free this memory properly. 2547 TemplateParamLists.release(); 2548 } 2549 2550 // C++ [dcl.fct.spec]p5: 2551 // The virtual specifier shall only be used in declarations of 2552 // nonstatic class member functions that appear within a 2553 // member-specification of a class declaration; see 10.3. 2554 // 2555 if (isVirtual && !NewFD->isInvalidDecl()) { 2556 if (!isVirtualOkay) { 2557 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2558 diag::err_virtual_non_function); 2559 } else if (!CurContext->isRecord()) { 2560 // 'virtual' was specified outside of the class. 2561 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2562 << CodeModificationHint::CreateRemoval( 2563 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2564 } else { 2565 // Okay: Add virtual to the method. 2566 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2567 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2568 CurClass->setAggregate(false); 2569 CurClass->setPOD(false); 2570 CurClass->setEmpty(false); 2571 CurClass->setPolymorphic(true); 2572 CurClass->setHasTrivialConstructor(false); 2573 CurClass->setHasTrivialCopyConstructor(false); 2574 CurClass->setHasTrivialCopyAssignment(false); 2575 } 2576 } 2577 2578 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2579 // Look for virtual methods in base classes that this method might override. 2580 2581 BasePaths Paths; 2582 if (LookupInBases(cast<CXXRecordDecl>(DC), 2583 MemberLookupCriteria(NewMD), Paths)) { 2584 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2585 E = Paths.found_decls_end(); I != E; ++I) { 2586 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2587 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2588 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2589 NewMD->addOverriddenMethod(OldMD); 2590 } 2591 } 2592 } 2593 } 2594 2595 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2596 !CurContext->isRecord()) { 2597 // C++ [class.static]p1: 2598 // A data or function member of a class may be declared static 2599 // in a class definition, in which case it is a static member of 2600 // the class. 2601 2602 // Complain about the 'static' specifier if it's on an out-of-line 2603 // member function definition. 2604 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2605 diag::err_static_out_of_line) 2606 << CodeModificationHint::CreateRemoval( 2607 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2608 } 2609 2610 // Handle GNU asm-label extension (encoded as an attribute). 2611 if (Expr *E = (Expr*) D.getAsmLabel()) { 2612 // The parser guarantees this is a string. 2613 StringLiteral *SE = cast<StringLiteral>(E); 2614 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2615 SE->getByteLength()))); 2616 } 2617 2618 // Copy the parameter declarations from the declarator D to the function 2619 // declaration NewFD, if they are available. First scavenge them into Params. 2620 llvm::SmallVector<ParmVarDecl*, 16> Params; 2621 if (D.getNumTypeObjects() > 0) { 2622 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2623 2624 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2625 // function that takes no arguments, not a function that takes a 2626 // single void argument. 2627 // We let through "const void" here because Sema::GetTypeForDeclarator 2628 // already checks for that case. 2629 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2630 FTI.ArgInfo[0].Param && 2631 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2632 // Empty arg list, don't push any params. 2633 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2634 2635 // In C++, the empty parameter-type-list must be spelled "void"; a 2636 // typedef of void is not permitted. 2637 if (getLangOptions().CPlusPlus && 2638 Param->getType().getUnqualifiedType() != Context.VoidTy) 2639 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2640 // FIXME: Leaks decl? 2641 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2642 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2643 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2644 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2645 Param->setDeclContext(NewFD); 2646 Params.push_back(Param); 2647 } 2648 } 2649 2650 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2651 // When we're declaring a function with a typedef, typeof, etc as in the 2652 // following example, we'll need to synthesize (unnamed) 2653 // parameters for use in the declaration. 2654 // 2655 // @code 2656 // typedef void fn(int); 2657 // fn f; 2658 // @endcode 2659 2660 // Synthesize a parameter for each argument type. 2661 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2662 AE = FT->arg_type_end(); AI != AE; ++AI) { 2663 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2664 SourceLocation(), 0, 2665 *AI, /*DInfo=*/0, 2666 VarDecl::None, 0); 2667 Param->setImplicit(); 2668 Params.push_back(Param); 2669 } 2670 } else { 2671 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2672 "Should not need args for typedef of non-prototype fn"); 2673 } 2674 // Finally, we know we have the right number of parameters, install them. 2675 NewFD->setParams(Context, Params.data(), Params.size()); 2676 2677 // If name lookup finds a previous declaration that is not in the 2678 // same scope as the new declaration, this may still be an 2679 // acceptable redeclaration. 2680 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2681 !(NewFD->hasLinkage() && 2682 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2683 PrevDecl = 0; 2684 2685 // FIXME: If the declarator has a template argument list but 2686 // isFunctionTemplateSpecialization is false, this is a function template 2687 // specialization but the user forgot the "template<>" header. Complain about 2688 // the missing template<> header and set isFunctionTemplateSpecialization. 2689 2690 if (isFunctionTemplateSpecialization && 2691 CheckFunctionTemplateSpecialization(NewFD, 2692 /*FIXME:*/false, SourceLocation(), 2693 0, 0, SourceLocation(), 2694 PrevDecl)) 2695 NewFD->setInvalidDecl(); 2696 2697 // Perform semantic checking on the function declaration. 2698 bool OverloadableAttrRequired = false; // FIXME: HACK! 2699 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2700 /*FIXME:*/OverloadableAttrRequired); 2701 2702 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2703 // An out-of-line member function declaration must also be a 2704 // definition (C++ [dcl.meaning]p1). 2705 // FIXME: Find a better way to recognize out-of-line specializations! 2706 if (!IsFunctionDefinition && !isFriend && 2707 !(TemplateParamLists.size() && !FunctionTemplate)) { 2708 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2709 << D.getCXXScopeSpec().getRange(); 2710 NewFD->setInvalidDecl(); 2711 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2712 // The user tried to provide an out-of-line definition for a 2713 // function that is a member of a class or namespace, but there 2714 // was no such member function declared (C++ [class.mfct]p2, 2715 // C++ [namespace.memdef]p2). For example: 2716 // 2717 // class X { 2718 // void f() const; 2719 // }; 2720 // 2721 // void X::f() { } // ill-formed 2722 // 2723 // Complain about this problem, and attempt to suggest close 2724 // matches (e.g., those that differ only in cv-qualifiers and 2725 // whether the parameter types are references). 2726 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2727 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2728 NewFD->setInvalidDecl(); 2729 2730 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2731 true); 2732 assert(!Prev.isAmbiguous() && 2733 "Cannot have an ambiguity in previous-declaration lookup"); 2734 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2735 Func != FuncEnd; ++Func) { 2736 if (isa<FunctionDecl>(*Func) && 2737 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2738 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2739 } 2740 2741 PrevDecl = 0; 2742 } 2743 } 2744 2745 // Handle attributes. We need to have merged decls when handling attributes 2746 // (for example to check for conflicts, etc). 2747 // FIXME: This needs to happen before we merge declarations. Then, 2748 // let attribute merging cope with attribute conflicts. 2749 ProcessDeclAttributes(S, NewFD, D); 2750 2751 // attributes declared post-definition are currently ignored 2752 if (Redeclaration && PrevDecl) { 2753 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2754 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2755 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2756 Diag(Def->getLocation(), diag::note_previous_definition); 2757 } 2758 } 2759 2760 AddKnownFunctionAttributes(NewFD); 2761 2762 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2763 // If a function name is overloadable in C, then every function 2764 // with that name must be marked "overloadable". 2765 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2766 << Redeclaration << NewFD; 2767 if (PrevDecl) 2768 Diag(PrevDecl->getLocation(), 2769 diag::note_attribute_overloadable_prev_overload); 2770 NewFD->addAttr(::new (Context) OverloadableAttr()); 2771 } 2772 2773 // If this is a locally-scoped extern C function, update the 2774 // map of such names. 2775 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2776 && !NewFD->isInvalidDecl()) 2777 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2778 2779 // Set this FunctionDecl's range up to the right paren. 2780 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2781 2782 if (FunctionTemplate && NewFD->isInvalidDecl()) 2783 FunctionTemplate->setInvalidDecl(); 2784 2785 if (FunctionTemplate) 2786 return FunctionTemplate; 2787 2788 return NewFD; 2789} 2790 2791/// \brief Perform semantic checking of a new function declaration. 2792/// 2793/// Performs semantic analysis of the new function declaration 2794/// NewFD. This routine performs all semantic checking that does not 2795/// require the actual declarator involved in the declaration, and is 2796/// used both for the declaration of functions as they are parsed 2797/// (called via ActOnDeclarator) and for the declaration of functions 2798/// that have been instantiated via C++ template instantiation (called 2799/// via InstantiateDecl). 2800/// 2801/// This sets NewFD->isInvalidDecl() to true if there was an error. 2802void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2803 bool &Redeclaration, 2804 bool &OverloadableAttrRequired) { 2805 // If NewFD is already known erroneous, don't do any of this checking. 2806 if (NewFD->isInvalidDecl()) 2807 return; 2808 2809 if (NewFD->getResultType()->isVariablyModifiedType()) { 2810 // Functions returning a variably modified type violate C99 6.7.5.2p2 2811 // because all functions have linkage. 2812 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2813 return NewFD->setInvalidDecl(); 2814 } 2815 2816 if (NewFD->isMain()) 2817 CheckMain(NewFD); 2818 2819 // Check for a previous declaration of this name. 2820 if (!PrevDecl && NewFD->isExternC()) { 2821 // Since we did not find anything by this name and we're declaring 2822 // an extern "C" function, look for a non-visible extern "C" 2823 // declaration with the same name. 2824 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2825 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2826 if (Pos != LocallyScopedExternalDecls.end()) 2827 PrevDecl = Pos->second; 2828 } 2829 2830 // Merge or overload the declaration with an existing declaration of 2831 // the same name, if appropriate. 2832 if (PrevDecl) { 2833 // Determine whether NewFD is an overload of PrevDecl or 2834 // a declaration that requires merging. If it's an overload, 2835 // there's no more work to do here; we'll just add the new 2836 // function to the scope. 2837 OverloadedFunctionDecl::function_iterator MatchedDecl; 2838 2839 if (!getLangOptions().CPlusPlus && 2840 AllowOverloadingOfFunction(PrevDecl, Context)) { 2841 OverloadableAttrRequired = true; 2842 2843 // Functions marked "overloadable" must have a prototype (that 2844 // we can't get through declaration merging). 2845 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2846 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2847 << NewFD; 2848 Redeclaration = true; 2849 2850 // Turn this into a variadic function with no parameters. 2851 QualType R = Context.getFunctionType( 2852 NewFD->getType()->getAs<FunctionType>()->getResultType(), 2853 0, 0, true, 0); 2854 NewFD->setType(R); 2855 return NewFD->setInvalidDecl(); 2856 } 2857 } 2858 2859 if (PrevDecl && 2860 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2861 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 2862 Redeclaration = true; 2863 Decl *OldDecl = PrevDecl; 2864 2865 // If PrevDecl was an overloaded function, extract the 2866 // FunctionDecl that matched. 2867 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2868 OldDecl = *MatchedDecl; 2869 2870 // NewFD and OldDecl represent declarations that need to be 2871 // merged. 2872 if (MergeFunctionDecl(NewFD, OldDecl)) 2873 return NewFD->setInvalidDecl(); 2874 2875 if (FunctionTemplateDecl *OldTemplateDecl 2876 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2877 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2878 else { 2879 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2880 NewFD->setAccess(OldDecl->getAccess()); 2881 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2882 } 2883 } 2884 } 2885 2886 // Semantic checking for this function declaration (in isolation). 2887 if (getLangOptions().CPlusPlus) { 2888 // C++-specific checks. 2889 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2890 CheckConstructor(Constructor); 2891 } else if (isa<CXXDestructorDecl>(NewFD)) { 2892 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2893 QualType ClassType = Context.getTypeDeclType(Record); 2894 if (!ClassType->isDependentType()) { 2895 DeclarationName Name 2896 = Context.DeclarationNames.getCXXDestructorName( 2897 Context.getCanonicalType(ClassType)); 2898 if (NewFD->getDeclName() != Name) { 2899 Diag(NewFD->getLocation(), diag::err_destructor_name); 2900 return NewFD->setInvalidDecl(); 2901 } 2902 } 2903 Record->setUserDeclaredDestructor(true); 2904 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2905 // user-defined destructor. 2906 Record->setPOD(false); 2907 2908 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2909 // declared destructor. 2910 // FIXME: C++0x: don't do this for "= default" destructors 2911 Record->setHasTrivialDestructor(false); 2912 } else if (CXXConversionDecl *Conversion 2913 = dyn_cast<CXXConversionDecl>(NewFD)) 2914 ActOnConversionDeclarator(Conversion); 2915 2916 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2917 if (NewFD->isOverloadedOperator() && 2918 CheckOverloadedOperatorDeclaration(NewFD)) 2919 return NewFD->setInvalidDecl(); 2920 2921 // In C++, check default arguments now that we have merged decls. Unless 2922 // the lexical context is the class, because in this case this is done 2923 // during delayed parsing anyway. 2924 if (!CurContext->isRecord()) 2925 CheckCXXDefaultArguments(NewFD); 2926 } 2927} 2928 2929void Sema::CheckMain(FunctionDecl* FD) { 2930 // C++ [basic.start.main]p3: A program that declares main to be inline 2931 // or static is ill-formed. 2932 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2933 // shall not appear in a declaration of main. 2934 // static main is not an error under C99, but we should warn about it. 2935 bool isInline = FD->isInline(); 2936 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2937 if (isInline || isStatic) { 2938 unsigned diagID = diag::warn_unusual_main_decl; 2939 if (isInline || getLangOptions().CPlusPlus) 2940 diagID = diag::err_unusual_main_decl; 2941 2942 int which = isStatic + (isInline << 1) - 1; 2943 Diag(FD->getLocation(), diagID) << which; 2944 } 2945 2946 QualType T = FD->getType(); 2947 assert(T->isFunctionType() && "function decl is not of function type"); 2948 const FunctionType* FT = T->getAs<FunctionType>(); 2949 2950 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2951 // TODO: add a replacement fixit to turn the return type into 'int'. 2952 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2953 FD->setInvalidDecl(true); 2954 } 2955 2956 // Treat protoless main() as nullary. 2957 if (isa<FunctionNoProtoType>(FT)) return; 2958 2959 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2960 unsigned nparams = FTP->getNumArgs(); 2961 assert(FD->getNumParams() == nparams); 2962 2963 if (nparams > 3) { 2964 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2965 FD->setInvalidDecl(true); 2966 nparams = 3; 2967 } 2968 2969 // FIXME: a lot of the following diagnostics would be improved 2970 // if we had some location information about types. 2971 2972 QualType CharPP = 2973 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2974 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2975 2976 for (unsigned i = 0; i < nparams; ++i) { 2977 QualType AT = FTP->getArgType(i); 2978 2979 bool mismatch = true; 2980 2981 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2982 mismatch = false; 2983 else if (Expected[i] == CharPP) { 2984 // As an extension, the following forms are okay: 2985 // char const ** 2986 // char const * const * 2987 // char * const * 2988 2989 QualifierCollector qs; 2990 const PointerType* PT; 2991 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 2992 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 2993 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 2994 qs.removeConst(); 2995 mismatch = !qs.empty(); 2996 } 2997 } 2998 2999 if (mismatch) { 3000 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3001 // TODO: suggest replacing given type with expected type 3002 FD->setInvalidDecl(true); 3003 } 3004 } 3005 3006 if (nparams == 1 && !FD->isInvalidDecl()) { 3007 Diag(FD->getLocation(), diag::warn_main_one_arg); 3008 } 3009} 3010 3011bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3012 // FIXME: Need strict checking. In C89, we need to check for 3013 // any assignment, increment, decrement, function-calls, or 3014 // commas outside of a sizeof. In C99, it's the same list, 3015 // except that the aforementioned are allowed in unevaluated 3016 // expressions. Everything else falls under the 3017 // "may accept other forms of constant expressions" exception. 3018 // (We never end up here for C++, so the constant expression 3019 // rules there don't matter.) 3020 if (Init->isConstantInitializer(Context)) 3021 return false; 3022 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3023 << Init->getSourceRange(); 3024 return true; 3025} 3026 3027void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3028 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3029} 3030 3031/// AddInitializerToDecl - Adds the initializer Init to the 3032/// declaration dcl. If DirectInit is true, this is C++ direct 3033/// initialization rather than copy initialization. 3034void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3035 Decl *RealDecl = dcl.getAs<Decl>(); 3036 // If there is no declaration, there was an error parsing it. Just ignore 3037 // the initializer. 3038 if (RealDecl == 0) 3039 return; 3040 3041 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3042 // With declarators parsed the way they are, the parser cannot 3043 // distinguish between a normal initializer and a pure-specifier. 3044 // Thus this grotesque test. 3045 IntegerLiteral *IL; 3046 Expr *Init = static_cast<Expr *>(init.get()); 3047 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3048 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3049 if (Method->isVirtualAsWritten()) { 3050 Method->setPure(); 3051 3052 // A class is abstract if at least one function is pure virtual. 3053 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3054 } else if (!Method->isInvalidDecl()) { 3055 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3056 << Method->getDeclName() << Init->getSourceRange(); 3057 Method->setInvalidDecl(); 3058 } 3059 } else { 3060 Diag(Method->getLocation(), diag::err_member_function_initialization) 3061 << Method->getDeclName() << Init->getSourceRange(); 3062 Method->setInvalidDecl(); 3063 } 3064 return; 3065 } 3066 3067 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3068 if (!VDecl) { 3069 if (getLangOptions().CPlusPlus && 3070 RealDecl->getLexicalDeclContext()->isRecord() && 3071 isa<NamedDecl>(RealDecl)) 3072 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3073 << cast<NamedDecl>(RealDecl)->getDeclName(); 3074 else 3075 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3076 RealDecl->setInvalidDecl(); 3077 return; 3078 } 3079 3080 if (!VDecl->getType()->isArrayType() && 3081 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3082 diag::err_typecheck_decl_incomplete_type)) { 3083 RealDecl->setInvalidDecl(); 3084 return; 3085 } 3086 3087 const VarDecl *Def = 0; 3088 if (VDecl->getDefinition(Def)) { 3089 Diag(VDecl->getLocation(), diag::err_redefinition) 3090 << VDecl->getDeclName(); 3091 Diag(Def->getLocation(), diag::note_previous_definition); 3092 VDecl->setInvalidDecl(); 3093 return; 3094 } 3095 3096 // Take ownership of the expression, now that we're sure we have somewhere 3097 // to put it. 3098 Expr *Init = init.takeAs<Expr>(); 3099 assert(Init && "missing initializer"); 3100 3101 // Get the decls type and save a reference for later, since 3102 // CheckInitializerTypes may change it. 3103 QualType DclT = VDecl->getType(), SavT = DclT; 3104 if (VDecl->isBlockVarDecl()) { 3105 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3106 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3107 VDecl->setInvalidDecl(); 3108 } else if (!VDecl->isInvalidDecl()) { 3109 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3110 VDecl->getDeclName(), DirectInit)) 3111 VDecl->setInvalidDecl(); 3112 3113 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3114 // Don't check invalid declarations to avoid emitting useless diagnostics. 3115 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3116 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3117 CheckForConstantInitializer(Init, DclT); 3118 } 3119 } 3120 } else if (VDecl->isStaticDataMember() && 3121 VDecl->getLexicalDeclContext()->isRecord()) { 3122 // This is an in-class initialization for a static data member, e.g., 3123 // 3124 // struct S { 3125 // static const int value = 17; 3126 // }; 3127 3128 // Attach the initializer 3129 VDecl->setInit(Context, Init); 3130 3131 // C++ [class.mem]p4: 3132 // A member-declarator can contain a constant-initializer only 3133 // if it declares a static member (9.4) of const integral or 3134 // const enumeration type, see 9.4.2. 3135 QualType T = VDecl->getType(); 3136 if (!T->isDependentType() && 3137 (!Context.getCanonicalType(T).isConstQualified() || 3138 !T->isIntegralType())) { 3139 Diag(VDecl->getLocation(), diag::err_member_initialization) 3140 << VDecl->getDeclName() << Init->getSourceRange(); 3141 VDecl->setInvalidDecl(); 3142 } else { 3143 // C++ [class.static.data]p4: 3144 // If a static data member is of const integral or const 3145 // enumeration type, its declaration in the class definition 3146 // can specify a constant-initializer which shall be an 3147 // integral constant expression (5.19). 3148 if (!Init->isTypeDependent() && 3149 !Init->getType()->isIntegralType()) { 3150 // We have a non-dependent, non-integral or enumeration type. 3151 Diag(Init->getSourceRange().getBegin(), 3152 diag::err_in_class_initializer_non_integral_type) 3153 << Init->getType() << Init->getSourceRange(); 3154 VDecl->setInvalidDecl(); 3155 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3156 // Check whether the expression is a constant expression. 3157 llvm::APSInt Value; 3158 SourceLocation Loc; 3159 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3160 Diag(Loc, diag::err_in_class_initializer_non_constant) 3161 << Init->getSourceRange(); 3162 VDecl->setInvalidDecl(); 3163 } else if (!VDecl->getType()->isDependentType()) 3164 ImpCastExprToType(Init, VDecl->getType()); 3165 } 3166 } 3167 } else if (VDecl->isFileVarDecl()) { 3168 if (VDecl->getStorageClass() == VarDecl::Extern) 3169 Diag(VDecl->getLocation(), diag::warn_extern_init); 3170 if (!VDecl->isInvalidDecl()) 3171 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3172 VDecl->getDeclName(), DirectInit)) 3173 VDecl->setInvalidDecl(); 3174 3175 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3176 // Don't check invalid declarations to avoid emitting useless diagnostics. 3177 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3178 // C99 6.7.8p4. All file scoped initializers need to be constant. 3179 CheckForConstantInitializer(Init, DclT); 3180 } 3181 } 3182 // If the type changed, it means we had an incomplete type that was 3183 // completed by the initializer. For example: 3184 // int ary[] = { 1, 3, 5 }; 3185 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3186 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3187 VDecl->setType(DclT); 3188 Init->setType(DclT); 3189 } 3190 3191 Init = MaybeCreateCXXExprWithTemporaries(Init, 3192 /*ShouldDestroyTemporaries=*/true); 3193 // Attach the initializer to the decl. 3194 VDecl->setInit(Context, Init); 3195 3196 // If the previous declaration of VDecl was a tentative definition, 3197 // remove it from the set of tentative definitions. 3198 if (VDecl->getPreviousDeclaration() && 3199 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3200 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3201 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3202 } 3203 3204 return; 3205} 3206 3207void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3208 bool TypeContainsUndeducedAuto) { 3209 Decl *RealDecl = dcl.getAs<Decl>(); 3210 3211 // If there is no declaration, there was an error parsing it. Just ignore it. 3212 if (RealDecl == 0) 3213 return; 3214 3215 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3216 QualType Type = Var->getType(); 3217 3218 // Record tentative definitions. 3219 if (Var->isTentativeDefinition(Context)) { 3220 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3221 InsertPair = 3222 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3223 3224 // Keep the latest definition in the map. If we see 'int i; int i;' we 3225 // want the second one in the map. 3226 InsertPair.first->second = Var; 3227 3228 // However, for the list, we don't care about the order, just make sure 3229 // that there are no dupes for a given declaration name. 3230 if (InsertPair.second) 3231 TentativeDefinitionList.push_back(Var->getDeclName()); 3232 } 3233 3234 // C++ [dcl.init.ref]p3: 3235 // The initializer can be omitted for a reference only in a 3236 // parameter declaration (8.3.5), in the declaration of a 3237 // function return type, in the declaration of a class member 3238 // within its class declaration (9.2), and where the extern 3239 // specifier is explicitly used. 3240 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3241 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3242 << Var->getDeclName() 3243 << SourceRange(Var->getLocation(), Var->getLocation()); 3244 Var->setInvalidDecl(); 3245 return; 3246 } 3247 3248 // C++0x [dcl.spec.auto]p3 3249 if (TypeContainsUndeducedAuto) { 3250 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3251 << Var->getDeclName() << Type; 3252 Var->setInvalidDecl(); 3253 return; 3254 } 3255 3256 // C++ [dcl.init]p9: 3257 // If no initializer is specified for an object, and the object 3258 // is of (possibly cv-qualified) non-POD class type (or array 3259 // thereof), the object shall be default-initialized; if the 3260 // object is of const-qualified type, the underlying class type 3261 // shall have a user-declared default constructor. 3262 // 3263 // FIXME: Diagnose the "user-declared default constructor" bit. 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()) && 3269 InitType->isRecordType() && !InitType->isDependentType()) { 3270 if (!RequireCompleteType(Var->getLocation(), InitType, 3271 diag::err_invalid_incomplete_type_use)) { 3272 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3273 3274 CXXConstructorDecl *Constructor 3275 = PerformInitializationByConstructor(InitType, 3276 MultiExprArg(*this, 0, 0), 3277 Var->getLocation(), 3278 SourceRange(Var->getLocation(), 3279 Var->getLocation()), 3280 Var->getDeclName(), 3281 IK_Default, 3282 ConstructorArgs); 3283 3284 // FIXME: Location info for the variable initialization? 3285 if (!Constructor) 3286 Var->setInvalidDecl(); 3287 else { 3288 // FIXME: Cope with initialization of arrays 3289 if (!Constructor->isTrivial() && 3290 InitializeVarWithConstructor(Var, Constructor, InitType, 3291 move_arg(ConstructorArgs))) 3292 Var->setInvalidDecl(); 3293 3294 FinalizeVarWithDestructor(Var, InitType); 3295 } 3296 } 3297 } 3298 } 3299 3300#if 0 3301 // FIXME: Temporarily disabled because we are not properly parsing 3302 // linkage specifications on declarations, e.g., 3303 // 3304 // extern "C" const CGPoint CGPointerZero; 3305 // 3306 // C++ [dcl.init]p9: 3307 // 3308 // If no initializer is specified for an object, and the 3309 // object is of (possibly cv-qualified) non-POD class type (or 3310 // array thereof), the object shall be default-initialized; if 3311 // the object is of const-qualified type, the underlying class 3312 // type shall have a user-declared default 3313 // constructor. Otherwise, if no initializer is specified for 3314 // an object, the object and its subobjects, if any, have an 3315 // indeterminate initial value; if the object or any of its 3316 // subobjects are of const-qualified type, the program is 3317 // ill-formed. 3318 // 3319 // This isn't technically an error in C, so we don't diagnose it. 3320 // 3321 // FIXME: Actually perform the POD/user-defined default 3322 // constructor check. 3323 if (getLangOptions().CPlusPlus && 3324 Context.getCanonicalType(Type).isConstQualified() && 3325 !Var->hasExternalStorage()) 3326 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3327 << Var->getName() 3328 << SourceRange(Var->getLocation(), Var->getLocation()); 3329#endif 3330 } 3331} 3332 3333Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3334 DeclPtrTy *Group, 3335 unsigned NumDecls) { 3336 llvm::SmallVector<Decl*, 8> Decls; 3337 3338 if (DS.isTypeSpecOwned()) 3339 Decls.push_back((Decl*)DS.getTypeRep()); 3340 3341 for (unsigned i = 0; i != NumDecls; ++i) 3342 if (Decl *D = Group[i].getAs<Decl>()) 3343 Decls.push_back(D); 3344 3345 // Perform semantic analysis that depends on having fully processed both 3346 // the declarator and initializer. 3347 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3348 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3349 if (!IDecl) 3350 continue; 3351 QualType T = IDecl->getType(); 3352 3353 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3354 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3355 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3356 if (!IDecl->isInvalidDecl() && 3357 RequireCompleteType(IDecl->getLocation(), T, 3358 diag::err_typecheck_decl_incomplete_type)) 3359 IDecl->setInvalidDecl(); 3360 } 3361 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3362 // object that has file scope without an initializer, and without a 3363 // storage-class specifier or with the storage-class specifier "static", 3364 // constitutes a tentative definition. Note: A tentative definition with 3365 // external linkage is valid (C99 6.2.2p5). 3366 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3367 if (const IncompleteArrayType *ArrayT 3368 = Context.getAsIncompleteArrayType(T)) { 3369 if (RequireCompleteType(IDecl->getLocation(), 3370 ArrayT->getElementType(), 3371 diag::err_illegal_decl_array_incomplete_type)) 3372 IDecl->setInvalidDecl(); 3373 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3374 // C99 6.9.2p3: If the declaration of an identifier for an object is 3375 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3376 // declared type shall not be an incomplete type. 3377 // NOTE: code such as the following 3378 // static struct s; 3379 // struct s { int a; }; 3380 // is accepted by gcc. Hence here we issue a warning instead of 3381 // an error and we do not invalidate the static declaration. 3382 // NOTE: to avoid multiple warnings, only check the first declaration. 3383 if (IDecl->getPreviousDeclaration() == 0) 3384 RequireCompleteType(IDecl->getLocation(), T, 3385 diag::ext_typecheck_decl_incomplete_type); 3386 } 3387 } 3388 } 3389 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3390 Decls.data(), Decls.size())); 3391} 3392 3393 3394/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3395/// to introduce parameters into function prototype scope. 3396Sema::DeclPtrTy 3397Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3398 const DeclSpec &DS = D.getDeclSpec(); 3399 3400 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3401 VarDecl::StorageClass StorageClass = VarDecl::None; 3402 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3403 StorageClass = VarDecl::Register; 3404 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3405 Diag(DS.getStorageClassSpecLoc(), 3406 diag::err_invalid_storage_class_in_func_decl); 3407 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3408 } 3409 3410 if (D.getDeclSpec().isThreadSpecified()) 3411 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3412 3413 DiagnoseFunctionSpecifiers(D); 3414 3415 // Check that there are no default arguments inside the type of this 3416 // parameter (C++ only). 3417 if (getLangOptions().CPlusPlus) 3418 CheckExtraCXXDefaultArguments(D); 3419 3420 DeclaratorInfo *DInfo = 0; 3421 TagDecl *OwnedDecl = 0; 3422 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3423 &OwnedDecl); 3424 3425 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3426 // C++ [dcl.fct]p6: 3427 // Types shall not be defined in return or parameter types. 3428 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3429 << Context.getTypeDeclType(OwnedDecl); 3430 } 3431 3432 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3433 // Can this happen for params? We already checked that they don't conflict 3434 // among each other. Here they can only shadow globals, which is ok. 3435 IdentifierInfo *II = D.getIdentifier(); 3436 if (II) { 3437 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3438 if (PrevDecl->isTemplateParameter()) { 3439 // Maybe we will complain about the shadowed template parameter. 3440 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3441 // Just pretend that we didn't see the previous declaration. 3442 PrevDecl = 0; 3443 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3444 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3445 3446 // Recover by removing the name 3447 II = 0; 3448 D.SetIdentifier(0, D.getIdentifierLoc()); 3449 } 3450 } 3451 } 3452 3453 // Parameters can not be abstract class types. 3454 // For record types, this is done by the AbstractClassUsageDiagnoser once 3455 // the class has been completely parsed. 3456 if (!CurContext->isRecord() && 3457 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3458 diag::err_abstract_type_in_decl, 3459 AbstractParamType)) 3460 D.setInvalidType(true); 3461 3462 QualType T = adjustParameterType(parmDeclType); 3463 3464 ParmVarDecl *New; 3465 if (T == parmDeclType) // parameter type did not need adjustment 3466 New = ParmVarDecl::Create(Context, CurContext, 3467 D.getIdentifierLoc(), II, 3468 parmDeclType, DInfo, StorageClass, 3469 0); 3470 else // keep track of both the adjusted and unadjusted types 3471 New = OriginalParmVarDecl::Create(Context, CurContext, 3472 D.getIdentifierLoc(), II, T, DInfo, 3473 parmDeclType, StorageClass, 0); 3474 3475 if (D.isInvalidType()) 3476 New->setInvalidDecl(); 3477 3478 // Parameter declarators cannot be interface types. All ObjC objects are 3479 // passed by reference. 3480 if (T->isObjCInterfaceType()) { 3481 Diag(D.getIdentifierLoc(), 3482 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3483 New->setInvalidDecl(); 3484 } 3485 3486 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3487 if (D.getCXXScopeSpec().isSet()) { 3488 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3489 << D.getCXXScopeSpec().getRange(); 3490 New->setInvalidDecl(); 3491 } 3492 3493 // Add the parameter declaration into this scope. 3494 S->AddDecl(DeclPtrTy::make(New)); 3495 if (II) 3496 IdResolver.AddDecl(New); 3497 3498 ProcessDeclAttributes(S, New, D); 3499 3500 if (New->hasAttr<BlocksAttr>()) { 3501 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3502 } 3503 return DeclPtrTy::make(New); 3504} 3505 3506void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3507 SourceLocation LocAfterDecls) { 3508 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3509 "Not a function declarator!"); 3510 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3511 3512 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3513 // for a K&R function. 3514 if (!FTI.hasPrototype) { 3515 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3516 --i; 3517 if (FTI.ArgInfo[i].Param == 0) { 3518 std::string Code = " int "; 3519 Code += FTI.ArgInfo[i].Ident->getName(); 3520 Code += ";\n"; 3521 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3522 << FTI.ArgInfo[i].Ident 3523 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3524 3525 // Implicitly declare the argument as type 'int' for lack of a better 3526 // type. 3527 DeclSpec DS; 3528 const char* PrevSpec; // unused 3529 unsigned DiagID; // unused 3530 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3531 PrevSpec, DiagID); 3532 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3533 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3534 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3535 } 3536 } 3537 } 3538} 3539 3540Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3541 Declarator &D) { 3542 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3543 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3544 "Not a function declarator!"); 3545 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3546 3547 if (FTI.hasPrototype) { 3548 // FIXME: Diagnose arguments without names in C. 3549 } 3550 3551 Scope *ParentScope = FnBodyScope->getParent(); 3552 3553 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3554 MultiTemplateParamsArg(*this), 3555 /*IsFunctionDefinition=*/true); 3556 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3557} 3558 3559Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3560 if (!D) 3561 return D; 3562 FunctionDecl *FD = 0; 3563 3564 if (FunctionTemplateDecl *FunTmpl 3565 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3566 FD = FunTmpl->getTemplatedDecl(); 3567 else 3568 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3569 3570 CurFunctionNeedsScopeChecking = false; 3571 3572 // See if this is a redefinition. 3573 const FunctionDecl *Definition; 3574 if (FD->getBody(Definition)) { 3575 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3576 Diag(Definition->getLocation(), diag::note_previous_definition); 3577 } 3578 3579 // Builtin functions cannot be defined. 3580 if (unsigned BuiltinID = FD->getBuiltinID()) { 3581 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3582 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3583 FD->setInvalidDecl(); 3584 } 3585 } 3586 3587 // The return type of a function definition must be complete 3588 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3589 QualType ResultType = FD->getResultType(); 3590 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3591 !FD->isInvalidDecl() && 3592 RequireCompleteType(FD->getLocation(), ResultType, 3593 diag::err_func_def_incomplete_result)) 3594 FD->setInvalidDecl(); 3595 3596 // GNU warning -Wmissing-prototypes: 3597 // Warn if a global function is defined without a previous 3598 // prototype declaration. This warning is issued even if the 3599 // definition itself provides a prototype. The aim is to detect 3600 // global functions that fail to be declared in header files. 3601 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3602 !FD->isMain()) { 3603 bool MissingPrototype = true; 3604 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3605 Prev; Prev = Prev->getPreviousDeclaration()) { 3606 // Ignore any declarations that occur in function or method 3607 // scope, because they aren't visible from the header. 3608 if (Prev->getDeclContext()->isFunctionOrMethod()) 3609 continue; 3610 3611 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3612 break; 3613 } 3614 3615 if (MissingPrototype) 3616 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3617 } 3618 3619 if (FnBodyScope) 3620 PushDeclContext(FnBodyScope, FD); 3621 3622 // Check the validity of our function parameters 3623 CheckParmsForFunctionDef(FD); 3624 3625 // Introduce our parameters into the function scope 3626 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3627 ParmVarDecl *Param = FD->getParamDecl(p); 3628 Param->setOwningFunction(FD); 3629 3630 // If this has an identifier, add it to the scope stack. 3631 if (Param->getIdentifier() && FnBodyScope) 3632 PushOnScopeChains(Param, FnBodyScope); 3633 } 3634 3635 // Checking attributes of current function definition 3636 // dllimport attribute. 3637 if (FD->getAttr<DLLImportAttr>() && 3638 (!FD->getAttr<DLLExportAttr>())) { 3639 // dllimport attribute cannot be applied to definition. 3640 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3641 Diag(FD->getLocation(), 3642 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3643 << "dllimport"; 3644 FD->setInvalidDecl(); 3645 return DeclPtrTy::make(FD); 3646 } else { 3647 // If a symbol previously declared dllimport is later defined, the 3648 // attribute is ignored in subsequent references, and a warning is 3649 // emitted. 3650 Diag(FD->getLocation(), 3651 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3652 << FD->getNameAsCString() << "dllimport"; 3653 } 3654 } 3655 return DeclPtrTy::make(FD); 3656} 3657 3658Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3659 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3660} 3661 3662Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3663 bool IsInstantiation) { 3664 Decl *dcl = D.getAs<Decl>(); 3665 Stmt *Body = BodyArg.takeAs<Stmt>(); 3666 3667 FunctionDecl *FD = 0; 3668 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3669 if (FunTmpl) 3670 FD = FunTmpl->getTemplatedDecl(); 3671 else 3672 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3673 3674 if (FD) { 3675 FD->setBody(Body); 3676 if (FD->isMain()) 3677 // C and C++ allow for main to automagically return 0. 3678 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3679 FD->setHasImplicitReturnZero(true); 3680 else 3681 CheckFallThroughForFunctionDef(FD, Body); 3682 3683 if (!FD->isInvalidDecl()) 3684 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3685 3686 // C++ [basic.def.odr]p2: 3687 // [...] A virtual member function is used if it is not pure. [...] 3688 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3689 if (Method->isVirtual() && !Method->isPure()) 3690 MarkDeclarationReferenced(Method->getLocation(), Method); 3691 3692 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3693 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3694 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3695 MD->setBody(Body); 3696 CheckFallThroughForFunctionDef(MD, Body); 3697 MD->setEndLoc(Body->getLocEnd()); 3698 3699 if (!MD->isInvalidDecl()) 3700 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3701 } else { 3702 Body->Destroy(Context); 3703 return DeclPtrTy(); 3704 } 3705 if (!IsInstantiation) 3706 PopDeclContext(); 3707 3708 // Verify and clean out per-function state. 3709 3710 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3711 3712 // Check goto/label use. 3713 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3714 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3715 LabelStmt *L = I->second; 3716 3717 // Verify that we have no forward references left. If so, there was a goto 3718 // or address of a label taken, but no definition of it. Label fwd 3719 // definitions are indicated with a null substmt. 3720 if (L->getSubStmt() != 0) 3721 continue; 3722 3723 // Emit error. 3724 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3725 3726 // At this point, we have gotos that use the bogus label. Stitch it into 3727 // the function body so that they aren't leaked and that the AST is well 3728 // formed. 3729 if (Body == 0) { 3730 // The whole function wasn't parsed correctly, just delete this. 3731 L->Destroy(Context); 3732 continue; 3733 } 3734 3735 // Otherwise, the body is valid: we want to stitch the label decl into the 3736 // function somewhere so that it is properly owned and so that the goto 3737 // has a valid target. Do this by creating a new compound stmt with the 3738 // label in it. 3739 3740 // Give the label a sub-statement. 3741 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3742 3743 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3744 cast<CXXTryStmt>(Body)->getTryBlock() : 3745 cast<CompoundStmt>(Body); 3746 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3747 Elements.push_back(L); 3748 Compound->setStmts(Context, &Elements[0], Elements.size()); 3749 } 3750 FunctionLabelMap.clear(); 3751 3752 if (!Body) return D; 3753 3754 // Verify that that gotos and switch cases don't jump into scopes illegally. 3755 if (CurFunctionNeedsScopeChecking) 3756 DiagnoseInvalidJumps(Body); 3757 3758 // C++ constructors that have function-try-blocks can't have return 3759 // statements in the handlers of that block. (C++ [except.handle]p14) 3760 // Verify this. 3761 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3762 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3763 3764 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3765 computeBaseOrMembersToDestroy(Destructor); 3766 return D; 3767} 3768 3769/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3770/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3771NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3772 IdentifierInfo &II, Scope *S) { 3773 // Before we produce a declaration for an implicitly defined 3774 // function, see whether there was a locally-scoped declaration of 3775 // this name as a function or variable. If so, use that 3776 // (non-visible) declaration, and complain about it. 3777 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3778 = LocallyScopedExternalDecls.find(&II); 3779 if (Pos != LocallyScopedExternalDecls.end()) { 3780 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3781 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3782 return Pos->second; 3783 } 3784 3785 // Extension in C99. Legal in C90, but warn about it. 3786 if (getLangOptions().C99) 3787 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3788 else 3789 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3790 3791 // FIXME: handle stuff like: 3792 // void foo() { extern float X(); } 3793 // void bar() { X(); } <-- implicit decl for X in another scope. 3794 3795 // Set a Declarator for the implicit definition: int foo(); 3796 const char *Dummy; 3797 DeclSpec DS; 3798 unsigned DiagID; 3799 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3800 Error = Error; // Silence warning. 3801 assert(!Error && "Error setting up implicit decl!"); 3802 Declarator D(DS, Declarator::BlockContext); 3803 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3804 0, 0, false, SourceLocation(), 3805 false, 0,0,0, Loc, Loc, D), 3806 SourceLocation()); 3807 D.SetIdentifier(&II, Loc); 3808 3809 // Insert this function into translation-unit scope. 3810 3811 DeclContext *PrevDC = CurContext; 3812 CurContext = Context.getTranslationUnitDecl(); 3813 3814 FunctionDecl *FD = 3815 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3816 FD->setImplicit(); 3817 3818 CurContext = PrevDC; 3819 3820 AddKnownFunctionAttributes(FD); 3821 3822 return FD; 3823} 3824 3825/// \brief Adds any function attributes that we know a priori based on 3826/// the declaration of this function. 3827/// 3828/// These attributes can apply both to implicitly-declared builtins 3829/// (like __builtin___printf_chk) or to library-declared functions 3830/// like NSLog or printf. 3831void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3832 if (FD->isInvalidDecl()) 3833 return; 3834 3835 // If this is a built-in function, map its builtin attributes to 3836 // actual attributes. 3837 if (unsigned BuiltinID = FD->getBuiltinID()) { 3838 // Handle printf-formatting attributes. 3839 unsigned FormatIdx; 3840 bool HasVAListArg; 3841 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3842 if (!FD->getAttr<FormatAttr>()) 3843 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3844 HasVAListArg ? 0 : FormatIdx + 2)); 3845 } 3846 3847 // Mark const if we don't care about errno and that is the only 3848 // thing preventing the function from being const. This allows 3849 // IRgen to use LLVM intrinsics for such functions. 3850 if (!getLangOptions().MathErrno && 3851 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3852 if (!FD->getAttr<ConstAttr>()) 3853 FD->addAttr(::new (Context) ConstAttr()); 3854 } 3855 3856 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3857 FD->addAttr(::new (Context) NoReturnAttr()); 3858 } 3859 3860 IdentifierInfo *Name = FD->getIdentifier(); 3861 if (!Name) 3862 return; 3863 if ((!getLangOptions().CPlusPlus && 3864 FD->getDeclContext()->isTranslationUnit()) || 3865 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3866 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3867 LinkageSpecDecl::lang_c)) { 3868 // Okay: this could be a libc/libm/Objective-C function we know 3869 // about. 3870 } else 3871 return; 3872 3873 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3874 // FIXME: NSLog and NSLogv should be target specific 3875 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3876 // FIXME: We known better than our headers. 3877 const_cast<FormatAttr *>(Format)->setType("printf"); 3878 } else 3879 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3880 Name->isStr("NSLogv") ? 0 : 2)); 3881 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3882 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3883 // target-specific builtins, perhaps? 3884 if (!FD->getAttr<FormatAttr>()) 3885 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3886 Name->isStr("vasprintf") ? 0 : 3)); 3887 } 3888} 3889 3890TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3891 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3892 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3893 3894 // Scope manipulation handled by caller. 3895 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3896 D.getIdentifierLoc(), 3897 D.getIdentifier(), 3898 T); 3899 3900 if (const TagType *TT = T->getAs<TagType>()) { 3901 TagDecl *TD = TT->getDecl(); 3902 3903 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3904 // keep track of the TypedefDecl. 3905 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3906 TD->setTypedefForAnonDecl(NewTD); 3907 } 3908 3909 if (D.isInvalidType()) 3910 NewTD->setInvalidDecl(); 3911 return NewTD; 3912} 3913 3914 3915/// \brief Determine whether a tag with a given kind is acceptable 3916/// as a redeclaration of the given tag declaration. 3917/// 3918/// \returns true if the new tag kind is acceptable, false otherwise. 3919bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3920 TagDecl::TagKind NewTag, 3921 SourceLocation NewTagLoc, 3922 const IdentifierInfo &Name) { 3923 // C++ [dcl.type.elab]p3: 3924 // The class-key or enum keyword present in the 3925 // elaborated-type-specifier shall agree in kind with the 3926 // declaration to which the name in theelaborated-type-specifier 3927 // refers. This rule also applies to the form of 3928 // elaborated-type-specifier that declares a class-name or 3929 // friend class since it can be construed as referring to the 3930 // definition of the class. Thus, in any 3931 // elaborated-type-specifier, the enum keyword shall be used to 3932 // refer to an enumeration (7.2), the union class-keyshall be 3933 // used to refer to a union (clause 9), and either the class or 3934 // struct class-key shall be used to refer to a class (clause 9) 3935 // declared using the class or struct class-key. 3936 TagDecl::TagKind OldTag = Previous->getTagKind(); 3937 if (OldTag == NewTag) 3938 return true; 3939 3940 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3941 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3942 // Warn about the struct/class tag mismatch. 3943 bool isTemplate = false; 3944 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3945 isTemplate = Record->getDescribedClassTemplate(); 3946 3947 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3948 << (NewTag == TagDecl::TK_class) 3949 << isTemplate << &Name 3950 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3951 OldTag == TagDecl::TK_class? "class" : "struct"); 3952 Diag(Previous->getLocation(), diag::note_previous_use); 3953 return true; 3954 } 3955 return false; 3956} 3957 3958/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3959/// former case, Name will be non-null. In the later case, Name will be null. 3960/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3961/// reference/declaration/definition of a tag. 3962Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3963 SourceLocation KWLoc, const CXXScopeSpec &SS, 3964 IdentifierInfo *Name, SourceLocation NameLoc, 3965 AttributeList *Attr, AccessSpecifier AS, 3966 MultiTemplateParamsArg TemplateParameterLists, 3967 bool &OwnedDecl, bool &IsDependent) { 3968 // If this is not a definition, it must have a name. 3969 assert((Name != 0 || TUK == TUK_Definition) && 3970 "Nameless record must be a definition!"); 3971 3972 OwnedDecl = false; 3973 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 3974 3975 if (TUK != TUK_Reference) { 3976 if (TemplateParameterList *TemplateParams 3977 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3978 (TemplateParameterList**)TemplateParameterLists.get(), 3979 TemplateParameterLists.size())) { 3980 if (TUK == TUK_Friend) { 3981 // When declaring a friend template, we do want to match the 3982 // template parameters to the scope specifier, but don't go so far 3983 // as to try to declare a new template. 3984 } else if (TemplateParams->size() > 0) { 3985 // This is a declaration or definition of a class template (which may 3986 // be a member of another template). 3987 OwnedDecl = false; 3988 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 3989 SS, Name, NameLoc, Attr, 3990 TemplateParams, 3991 AS); 3992 TemplateParameterLists.release(); 3993 return Result.get(); 3994 } else { 3995 // FIXME: diagnose the extraneous 'template<>', once we recover 3996 // slightly better in ParseTemplate.cpp from bogus template 3997 // parameters. 3998 } 3999 } 4000 } 4001 4002 DeclContext *SearchDC = CurContext; 4003 DeclContext *DC = CurContext; 4004 NamedDecl *PrevDecl = 0; 4005 bool isStdBadAlloc = false; 4006 bool Invalid = false; 4007 4008 if (Name && SS.isNotEmpty()) { 4009 // We have a nested-name tag ('struct foo::bar'). 4010 4011 // Check for invalid 'foo::'. 4012 if (SS.isInvalid()) { 4013 Name = 0; 4014 goto CreateNewDecl; 4015 } 4016 4017 // If this is a friend or a reference to a class in a dependent 4018 // context, don't try to make a decl for it. 4019 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4020 DC = computeDeclContext(SS, false); 4021 if (!DC) { 4022 IsDependent = true; 4023 return DeclPtrTy(); 4024 } 4025 } 4026 4027 if (RequireCompleteDeclContext(SS)) 4028 return DeclPtrTy::make((Decl *)0); 4029 4030 DC = computeDeclContext(SS, true); 4031 SearchDC = DC; 4032 // Look-up name inside 'foo::'. 4033 PrevDecl 4034 = dyn_cast_or_null<TagDecl>( 4035 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4036 4037 // A tag 'foo::bar' must already exist. 4038 if (PrevDecl == 0) { 4039 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4040 Name = 0; 4041 Invalid = true; 4042 goto CreateNewDecl; 4043 } 4044 } else if (Name) { 4045 // If this is a named struct, check to see if there was a previous forward 4046 // declaration or definition. 4047 // FIXME: We're looking into outer scopes here, even when we 4048 // shouldn't be. Doing so can result in ambiguities that we 4049 // shouldn't be diagnosing. 4050 LookupResult R = LookupName(S, Name, LookupTagName, 4051 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4052 if (R.isAmbiguous()) { 4053 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4054 // FIXME: This is not best way to recover from case like: 4055 // 4056 // struct S s; 4057 // 4058 // causes needless "incomplete type" error later. 4059 Name = 0; 4060 PrevDecl = 0; 4061 Invalid = true; 4062 } else 4063 PrevDecl = R; 4064 4065 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4066 // FIXME: This makes sure that we ignore the contexts associated 4067 // with C structs, unions, and enums when looking for a matching 4068 // tag declaration or definition. See the similar lookup tweak 4069 // in Sema::LookupName; is there a better way to deal with this? 4070 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4071 SearchDC = SearchDC->getParent(); 4072 } 4073 } 4074 4075 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4076 // Maybe we will complain about the shadowed template parameter. 4077 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4078 // Just pretend that we didn't see the previous declaration. 4079 PrevDecl = 0; 4080 } 4081 4082 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4083 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4084 // This is a declaration of or a reference to "std::bad_alloc". 4085 isStdBadAlloc = true; 4086 4087 if (!PrevDecl && StdBadAlloc) { 4088 // std::bad_alloc has been implicitly declared (but made invisible to 4089 // name lookup). Fill in this implicit declaration as the previous 4090 // declaration, so that the declarations get chained appropriately. 4091 PrevDecl = StdBadAlloc; 4092 } 4093 } 4094 4095 if (PrevDecl) { 4096 // Check whether the previous declaration is usable. 4097 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4098 4099 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4100 // If this is a use of a previous tag, or if the tag is already declared 4101 // in the same scope (so that the definition/declaration completes or 4102 // rementions the tag), reuse the decl. 4103 if (TUK == TUK_Reference || TUK == TUK_Friend || 4104 isDeclInScope(PrevDecl, SearchDC, S)) { 4105 // Make sure that this wasn't declared as an enum and now used as a 4106 // struct or something similar. 4107 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4108 bool SafeToContinue 4109 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4110 Kind != TagDecl::TK_enum); 4111 if (SafeToContinue) 4112 Diag(KWLoc, diag::err_use_with_wrong_tag) 4113 << Name 4114 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4115 PrevTagDecl->getKindName()); 4116 else 4117 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4118 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4119 4120 if (SafeToContinue) 4121 Kind = PrevTagDecl->getTagKind(); 4122 else { 4123 // Recover by making this an anonymous redefinition. 4124 Name = 0; 4125 PrevDecl = 0; 4126 Invalid = true; 4127 } 4128 } 4129 4130 if (!Invalid) { 4131 // If this is a use, just return the declaration we found. 4132 4133 // FIXME: In the future, return a variant or some other clue 4134 // for the consumer of this Decl to know it doesn't own it. 4135 // For our current ASTs this shouldn't be a problem, but will 4136 // need to be changed with DeclGroups. 4137 if (TUK == TUK_Reference) 4138 return DeclPtrTy::make(PrevDecl); 4139 4140 // If this is a friend, make sure we create the new 4141 // declaration in the appropriate semantic context. 4142 if (TUK == TUK_Friend) 4143 SearchDC = PrevDecl->getDeclContext(); 4144 4145 // Diagnose attempts to redefine a tag. 4146 if (TUK == TUK_Definition) { 4147 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4148 Diag(NameLoc, diag::err_redefinition) << Name; 4149 Diag(Def->getLocation(), diag::note_previous_definition); 4150 // If this is a redefinition, recover by making this 4151 // struct be anonymous, which will make any later 4152 // references get the previous definition. 4153 Name = 0; 4154 PrevDecl = 0; 4155 Invalid = true; 4156 } else { 4157 // If the type is currently being defined, complain 4158 // about a nested redefinition. 4159 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4160 if (Tag->isBeingDefined()) { 4161 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4162 Diag(PrevTagDecl->getLocation(), 4163 diag::note_previous_definition); 4164 Name = 0; 4165 PrevDecl = 0; 4166 Invalid = true; 4167 } 4168 } 4169 4170 // Okay, this is definition of a previously declared or referenced 4171 // tag PrevDecl. We're going to create a new Decl for it. 4172 } 4173 } 4174 // If we get here we have (another) forward declaration or we 4175 // have a definition. Just create a new decl. 4176 4177 } else { 4178 // If we get here, this is a definition of a new tag type in a nested 4179 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4180 // new decl/type. We set PrevDecl to NULL so that the entities 4181 // have distinct types. 4182 PrevDecl = 0; 4183 } 4184 // If we get here, we're going to create a new Decl. If PrevDecl 4185 // is non-NULL, it's a definition of the tag declared by 4186 // PrevDecl. If it's NULL, we have a new definition. 4187 } else { 4188 // PrevDecl is a namespace, template, or anything else 4189 // that lives in the IDNS_Tag identifier namespace. 4190 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4191 // The tag name clashes with a namespace name, issue an error and 4192 // recover by making this tag be anonymous. 4193 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4194 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4195 Name = 0; 4196 PrevDecl = 0; 4197 Invalid = true; 4198 } else { 4199 // The existing declaration isn't relevant to us; we're in a 4200 // new scope, so clear out the previous declaration. 4201 PrevDecl = 0; 4202 } 4203 } 4204 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4205 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4206 // C++ [basic.scope.pdecl]p5: 4207 // -- for an elaborated-type-specifier of the form 4208 // 4209 // class-key identifier 4210 // 4211 // if the elaborated-type-specifier is used in the 4212 // decl-specifier-seq or parameter-declaration-clause of a 4213 // function defined in namespace scope, the identifier is 4214 // declared as a class-name in the namespace that contains 4215 // the declaration; otherwise, except as a friend 4216 // declaration, the identifier is declared in the smallest 4217 // non-class, non-function-prototype scope that contains the 4218 // declaration. 4219 // 4220 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4221 // C structs and unions. 4222 // 4223 // GNU C also supports this behavior as part of its incomplete 4224 // enum types extension, while GNU C++ does not. 4225 // 4226 // Find the context where we'll be declaring the tag. 4227 // FIXME: We would like to maintain the current DeclContext as the 4228 // lexical context, 4229 while (SearchDC->isRecord()) 4230 SearchDC = SearchDC->getParent(); 4231 4232 // Find the scope where we'll be declaring the tag. 4233 while (S->isClassScope() || 4234 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4235 ((S->getFlags() & Scope::DeclScope) == 0) || 4236 (S->getEntity() && 4237 ((DeclContext *)S->getEntity())->isTransparentContext())) 4238 S = S->getParent(); 4239 4240 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4241 // C++ [namespace.memdef]p3: 4242 // If a friend declaration in a non-local class first declares a 4243 // class or function, the friend class or function is a member of 4244 // the innermost enclosing namespace. 4245 while (!SearchDC->isFileContext()) 4246 SearchDC = SearchDC->getParent(); 4247 4248 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4249 while (S->getEntity() != SearchDC) 4250 S = S->getParent(); 4251 } 4252 4253CreateNewDecl: 4254 4255 // If there is an identifier, use the location of the identifier as the 4256 // location of the decl, otherwise use the location of the struct/union 4257 // keyword. 4258 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4259 4260 // Otherwise, create a new declaration. If there is a previous 4261 // declaration of the same entity, the two will be linked via 4262 // PrevDecl. 4263 TagDecl *New; 4264 4265 if (Kind == TagDecl::TK_enum) { 4266 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4267 // enum X { A, B, C } D; D should chain to X. 4268 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4269 cast_or_null<EnumDecl>(PrevDecl)); 4270 // If this is an undefined enum, warn. 4271 if (TUK != TUK_Definition && !Invalid) { 4272 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4273 : diag::ext_forward_ref_enum; 4274 Diag(Loc, DK); 4275 } 4276 } else { 4277 // struct/union/class 4278 4279 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4280 // struct X { int A; } D; D should chain to X. 4281 if (getLangOptions().CPlusPlus) { 4282 // FIXME: Look for a way to use RecordDecl for simple structs. 4283 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4284 cast_or_null<CXXRecordDecl>(PrevDecl)); 4285 4286 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4287 StdBadAlloc = cast<CXXRecordDecl>(New); 4288 } else 4289 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4290 cast_or_null<RecordDecl>(PrevDecl)); 4291 } 4292 4293 if (Kind != TagDecl::TK_enum) { 4294 // Handle #pragma pack: if the #pragma pack stack has non-default 4295 // alignment, make up a packed attribute for this decl. These 4296 // attributes are checked when the ASTContext lays out the 4297 // structure. 4298 // 4299 // It is important for implementing the correct semantics that this 4300 // happen here (in act on tag decl). The #pragma pack stack is 4301 // maintained as a result of parser callbacks which can occur at 4302 // many points during the parsing of a struct declaration (because 4303 // the #pragma tokens are effectively skipped over during the 4304 // parsing of the struct). 4305 if (unsigned Alignment = getPragmaPackAlignment()) 4306 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4307 } 4308 4309 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4310 // C++ [dcl.typedef]p3: 4311 // [...] Similarly, in a given scope, a class or enumeration 4312 // shall not be declared with the same name as a typedef-name 4313 // that is declared in that scope and refers to a type other 4314 // than the class or enumeration itself. 4315 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4316 TypedefDecl *PrevTypedef = 0; 4317 if (Lookup.getKind() == LookupResult::Found) 4318 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4319 4320 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4321 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4322 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4323 Diag(Loc, diag::err_tag_definition_of_typedef) 4324 << Context.getTypeDeclType(New) 4325 << PrevTypedef->getUnderlyingType(); 4326 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4327 Invalid = true; 4328 } 4329 } 4330 4331 if (Invalid) 4332 New->setInvalidDecl(); 4333 4334 if (Attr) 4335 ProcessDeclAttributeList(S, New, Attr); 4336 4337 // If we're declaring or defining a tag in function prototype scope 4338 // in C, note that this type can only be used within the function. 4339 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4340 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4341 4342 // Set the lexical context. If the tag has a C++ scope specifier, the 4343 // lexical context will be different from the semantic context. 4344 New->setLexicalDeclContext(CurContext); 4345 4346 // Mark this as a friend decl if applicable. 4347 if (TUK == TUK_Friend) 4348 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4349 4350 // Set the access specifier. 4351 if (!Invalid && TUK != TUK_Friend) 4352 SetMemberAccessSpecifier(New, PrevDecl, AS); 4353 4354 if (TUK == TUK_Definition) 4355 New->startDefinition(); 4356 4357 // If this has an identifier, add it to the scope stack. 4358 if (TUK == TUK_Friend) { 4359 // We might be replacing an existing declaration in the lookup tables; 4360 // if so, borrow its access specifier. 4361 if (PrevDecl) 4362 New->setAccess(PrevDecl->getAccess()); 4363 4364 // Friend tag decls are visible in fairly strange ways. 4365 if (!CurContext->isDependentContext()) { 4366 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4367 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4368 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4369 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4370 } 4371 } else if (Name) { 4372 S = getNonFieldDeclScope(S); 4373 PushOnScopeChains(New, S); 4374 } else { 4375 CurContext->addDecl(New); 4376 } 4377 4378 // If this is the C FILE type, notify the AST context. 4379 if (IdentifierInfo *II = New->getIdentifier()) 4380 if (!New->isInvalidDecl() && 4381 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4382 II->isStr("FILE")) 4383 Context.setFILEDecl(New); 4384 4385 OwnedDecl = true; 4386 return DeclPtrTy::make(New); 4387} 4388 4389void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4390 AdjustDeclIfTemplate(TagD); 4391 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4392 4393 // Enter the tag context. 4394 PushDeclContext(S, Tag); 4395 4396 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4397 FieldCollector->StartClass(); 4398 4399 if (Record->getIdentifier()) { 4400 // C++ [class]p2: 4401 // [...] The class-name is also inserted into the scope of the 4402 // class itself; this is known as the injected-class-name. For 4403 // purposes of access checking, the injected-class-name is treated 4404 // as if it were a public member name. 4405 CXXRecordDecl *InjectedClassName 4406 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4407 CurContext, Record->getLocation(), 4408 Record->getIdentifier(), 4409 Record->getTagKeywordLoc(), 4410 Record); 4411 InjectedClassName->setImplicit(); 4412 InjectedClassName->setAccess(AS_public); 4413 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4414 InjectedClassName->setDescribedClassTemplate(Template); 4415 PushOnScopeChains(InjectedClassName, S); 4416 assert(InjectedClassName->isInjectedClassName() && 4417 "Broken injected-class-name"); 4418 } 4419 } 4420} 4421 4422void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4423 SourceLocation RBraceLoc) { 4424 AdjustDeclIfTemplate(TagD); 4425 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4426 Tag->setRBraceLoc(RBraceLoc); 4427 4428 if (isa<CXXRecordDecl>(Tag)) 4429 FieldCollector->FinishClass(); 4430 4431 // Exit this scope of this tag's definition. 4432 PopDeclContext(); 4433 4434 // Notify the consumer that we've defined a tag. 4435 Consumer.HandleTagDeclDefinition(Tag); 4436} 4437 4438// Note that FieldName may be null for anonymous bitfields. 4439bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4440 QualType FieldTy, const Expr *BitWidth, 4441 bool *ZeroWidth) { 4442 // Default to true; that shouldn't confuse checks for emptiness 4443 if (ZeroWidth) 4444 *ZeroWidth = true; 4445 4446 // C99 6.7.2.1p4 - verify the field type. 4447 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4448 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4449 // Handle incomplete types with specific error. 4450 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4451 return true; 4452 if (FieldName) 4453 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4454 << FieldName << FieldTy << BitWidth->getSourceRange(); 4455 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4456 << FieldTy << BitWidth->getSourceRange(); 4457 } 4458 4459 // If the bit-width is type- or value-dependent, don't try to check 4460 // it now. 4461 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4462 return false; 4463 4464 llvm::APSInt Value; 4465 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4466 return true; 4467 4468 if (Value != 0 && ZeroWidth) 4469 *ZeroWidth = false; 4470 4471 // Zero-width bitfield is ok for anonymous field. 4472 if (Value == 0 && FieldName) 4473 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4474 4475 if (Value.isSigned() && Value.isNegative()) { 4476 if (FieldName) 4477 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4478 << FieldName << Value.toString(10); 4479 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4480 << Value.toString(10); 4481 } 4482 4483 if (!FieldTy->isDependentType()) { 4484 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4485 if (Value.getZExtValue() > TypeSize) { 4486 if (FieldName) 4487 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4488 << FieldName << (unsigned)TypeSize; 4489 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4490 << (unsigned)TypeSize; 4491 } 4492 } 4493 4494 return false; 4495} 4496 4497/// ActOnField - Each field of a struct/union/class is passed into this in order 4498/// to create a FieldDecl object for it. 4499Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4500 SourceLocation DeclStart, 4501 Declarator &D, ExprTy *BitfieldWidth) { 4502 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4503 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4504 AS_public); 4505 return DeclPtrTy::make(Res); 4506} 4507 4508/// HandleField - Analyze a field of a C struct or a C++ data member. 4509/// 4510FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4511 SourceLocation DeclStart, 4512 Declarator &D, Expr *BitWidth, 4513 AccessSpecifier AS) { 4514 IdentifierInfo *II = D.getIdentifier(); 4515 SourceLocation Loc = DeclStart; 4516 if (II) Loc = D.getIdentifierLoc(); 4517 4518 DeclaratorInfo *DInfo = 0; 4519 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4520 if (getLangOptions().CPlusPlus) 4521 CheckExtraCXXDefaultArguments(D); 4522 4523 DiagnoseFunctionSpecifiers(D); 4524 4525 if (D.getDeclSpec().isThreadSpecified()) 4526 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4527 4528 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4529 4530 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4531 // Maybe we will complain about the shadowed template parameter. 4532 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4533 // Just pretend that we didn't see the previous declaration. 4534 PrevDecl = 0; 4535 } 4536 4537 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4538 PrevDecl = 0; 4539 4540 bool Mutable 4541 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4542 SourceLocation TSSL = D.getSourceRange().getBegin(); 4543 FieldDecl *NewFD 4544 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4545 AS, PrevDecl, &D); 4546 if (NewFD->isInvalidDecl() && PrevDecl) { 4547 // Don't introduce NewFD into scope; there's already something 4548 // with the same name in the same scope. 4549 } else if (II) { 4550 PushOnScopeChains(NewFD, S); 4551 } else 4552 Record->addDecl(NewFD); 4553 4554 return NewFD; 4555} 4556 4557/// \brief Build a new FieldDecl and check its well-formedness. 4558/// 4559/// This routine builds a new FieldDecl given the fields name, type, 4560/// record, etc. \p PrevDecl should refer to any previous declaration 4561/// with the same name and in the same scope as the field to be 4562/// created. 4563/// 4564/// \returns a new FieldDecl. 4565/// 4566/// \todo The Declarator argument is a hack. It will be removed once 4567FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4568 DeclaratorInfo *DInfo, 4569 RecordDecl *Record, SourceLocation Loc, 4570 bool Mutable, Expr *BitWidth, 4571 SourceLocation TSSL, 4572 AccessSpecifier AS, NamedDecl *PrevDecl, 4573 Declarator *D) { 4574 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4575 bool InvalidDecl = false; 4576 if (D) InvalidDecl = D->isInvalidType(); 4577 4578 // If we receive a broken type, recover by assuming 'int' and 4579 // marking this declaration as invalid. 4580 if (T.isNull()) { 4581 InvalidDecl = true; 4582 T = Context.IntTy; 4583 } 4584 4585 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4586 // than a variably modified type. 4587 if (T->isVariablyModifiedType()) { 4588 bool SizeIsNegative; 4589 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4590 SizeIsNegative); 4591 if (!FixedTy.isNull()) { 4592 Diag(Loc, diag::warn_illegal_constant_array_size); 4593 T = FixedTy; 4594 } else { 4595 if (SizeIsNegative) 4596 Diag(Loc, diag::err_typecheck_negative_array_size); 4597 else 4598 Diag(Loc, diag::err_typecheck_field_variable_size); 4599 InvalidDecl = true; 4600 } 4601 } 4602 4603 // Fields can not have abstract class types 4604 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4605 AbstractFieldType)) 4606 InvalidDecl = true; 4607 4608 bool ZeroWidth = false; 4609 // If this is declared as a bit-field, check the bit-field. 4610 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4611 InvalidDecl = true; 4612 DeleteExpr(BitWidth); 4613 BitWidth = 0; 4614 ZeroWidth = false; 4615 } 4616 4617 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4618 BitWidth, Mutable); 4619 if (InvalidDecl) 4620 NewFD->setInvalidDecl(); 4621 4622 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4623 Diag(Loc, diag::err_duplicate_member) << II; 4624 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4625 NewFD->setInvalidDecl(); 4626 } 4627 4628 if (getLangOptions().CPlusPlus) { 4629 QualType EltTy = Context.getBaseElementType(T); 4630 4631 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4632 4633 if (!T->isPODType()) 4634 CXXRecord->setPOD(false); 4635 if (!ZeroWidth) 4636 CXXRecord->setEmpty(false); 4637 4638 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4639 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4640 4641 if (!RDecl->hasTrivialConstructor()) 4642 CXXRecord->setHasTrivialConstructor(false); 4643 if (!RDecl->hasTrivialCopyConstructor()) 4644 CXXRecord->setHasTrivialCopyConstructor(false); 4645 if (!RDecl->hasTrivialCopyAssignment()) 4646 CXXRecord->setHasTrivialCopyAssignment(false); 4647 if (!RDecl->hasTrivialDestructor()) 4648 CXXRecord->setHasTrivialDestructor(false); 4649 4650 // C++ 9.5p1: An object of a class with a non-trivial 4651 // constructor, a non-trivial copy constructor, a non-trivial 4652 // destructor, or a non-trivial copy assignment operator 4653 // cannot be a member of a union, nor can an array of such 4654 // objects. 4655 // TODO: C++0x alters this restriction significantly. 4656 if (Record->isUnion()) { 4657 // We check for copy constructors before constructors 4658 // because otherwise we'll never get complaints about 4659 // copy constructors. 4660 4661 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4662 4663 CXXSpecialMember member; 4664 if (!RDecl->hasTrivialCopyConstructor()) 4665 member = CXXCopyConstructor; 4666 else if (!RDecl->hasTrivialConstructor()) 4667 member = CXXDefaultConstructor; 4668 else if (!RDecl->hasTrivialCopyAssignment()) 4669 member = CXXCopyAssignment; 4670 else if (!RDecl->hasTrivialDestructor()) 4671 member = CXXDestructor; 4672 else 4673 member = invalid; 4674 4675 if (member != invalid) { 4676 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4677 DiagnoseNontrivial(RT, member); 4678 NewFD->setInvalidDecl(); 4679 } 4680 } 4681 } 4682 } 4683 4684 // FIXME: We need to pass in the attributes given an AST 4685 // representation, not a parser representation. 4686 if (D) 4687 // FIXME: What to pass instead of TUScope? 4688 ProcessDeclAttributes(TUScope, NewFD, *D); 4689 4690 if (T.isObjCGCWeak()) 4691 Diag(Loc, diag::warn_attribute_weak_on_field); 4692 4693 NewFD->setAccess(AS); 4694 4695 // C++ [dcl.init.aggr]p1: 4696 // An aggregate is an array or a class (clause 9) with [...] no 4697 // private or protected non-static data members (clause 11). 4698 // A POD must be an aggregate. 4699 if (getLangOptions().CPlusPlus && 4700 (AS == AS_private || AS == AS_protected)) { 4701 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4702 CXXRecord->setAggregate(false); 4703 CXXRecord->setPOD(false); 4704 } 4705 4706 return NewFD; 4707} 4708 4709/// DiagnoseNontrivial - Given that a class has a non-trivial 4710/// special member, figure out why. 4711void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4712 QualType QT(T, 0U); 4713 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4714 4715 // Check whether the member was user-declared. 4716 switch (member) { 4717 case CXXDefaultConstructor: 4718 if (RD->hasUserDeclaredConstructor()) { 4719 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4720 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4721 if (!ci->isImplicitlyDefined(Context)) { 4722 SourceLocation CtorLoc = ci->getLocation(); 4723 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4724 return; 4725 } 4726 4727 assert(0 && "found no user-declared constructors"); 4728 return; 4729 } 4730 break; 4731 4732 case CXXCopyConstructor: 4733 if (RD->hasUserDeclaredCopyConstructor()) { 4734 SourceLocation CtorLoc = 4735 RD->getCopyConstructor(Context, 0)->getLocation(); 4736 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4737 return; 4738 } 4739 break; 4740 4741 case CXXCopyAssignment: 4742 if (RD->hasUserDeclaredCopyAssignment()) { 4743 // FIXME: this should use the location of the copy 4744 // assignment, not the type. 4745 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4746 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4747 return; 4748 } 4749 break; 4750 4751 case CXXDestructor: 4752 if (RD->hasUserDeclaredDestructor()) { 4753 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4754 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4755 return; 4756 } 4757 break; 4758 } 4759 4760 typedef CXXRecordDecl::base_class_iterator base_iter; 4761 4762 // Virtual bases and members inhibit trivial copying/construction, 4763 // but not trivial destruction. 4764 if (member != CXXDestructor) { 4765 // Check for virtual bases. vbases includes indirect virtual bases, 4766 // so we just iterate through the direct bases. 4767 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4768 if (bi->isVirtual()) { 4769 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4770 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4771 return; 4772 } 4773 4774 // Check for virtual methods. 4775 typedef CXXRecordDecl::method_iterator meth_iter; 4776 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4777 ++mi) { 4778 if (mi->isVirtual()) { 4779 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4780 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4781 return; 4782 } 4783 } 4784 } 4785 4786 bool (CXXRecordDecl::*hasTrivial)() const; 4787 switch (member) { 4788 case CXXDefaultConstructor: 4789 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4790 case CXXCopyConstructor: 4791 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4792 case CXXCopyAssignment: 4793 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4794 case CXXDestructor: 4795 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4796 default: 4797 assert(0 && "unexpected special member"); return; 4798 } 4799 4800 // Check for nontrivial bases (and recurse). 4801 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4802 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4803 assert(BaseRT); 4804 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4805 if (!(BaseRecTy->*hasTrivial)()) { 4806 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4807 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4808 DiagnoseNontrivial(BaseRT, member); 4809 return; 4810 } 4811 } 4812 4813 // Check for nontrivial members (and recurse). 4814 typedef RecordDecl::field_iterator field_iter; 4815 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4816 ++fi) { 4817 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4818 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4819 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4820 4821 if (!(EltRD->*hasTrivial)()) { 4822 SourceLocation FLoc = (*fi)->getLocation(); 4823 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4824 DiagnoseNontrivial(EltRT, member); 4825 return; 4826 } 4827 } 4828 } 4829 4830 assert(0 && "found no explanation for non-trivial member"); 4831} 4832 4833/// TranslateIvarVisibility - Translate visibility from a token ID to an 4834/// AST enum value. 4835static ObjCIvarDecl::AccessControl 4836TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4837 switch (ivarVisibility) { 4838 default: assert(0 && "Unknown visitibility kind"); 4839 case tok::objc_private: return ObjCIvarDecl::Private; 4840 case tok::objc_public: return ObjCIvarDecl::Public; 4841 case tok::objc_protected: return ObjCIvarDecl::Protected; 4842 case tok::objc_package: return ObjCIvarDecl::Package; 4843 } 4844} 4845 4846/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4847/// in order to create an IvarDecl object for it. 4848Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4849 SourceLocation DeclStart, 4850 DeclPtrTy IntfDecl, 4851 Declarator &D, ExprTy *BitfieldWidth, 4852 tok::ObjCKeywordKind Visibility) { 4853 4854 IdentifierInfo *II = D.getIdentifier(); 4855 Expr *BitWidth = (Expr*)BitfieldWidth; 4856 SourceLocation Loc = DeclStart; 4857 if (II) Loc = D.getIdentifierLoc(); 4858 4859 // FIXME: Unnamed fields can be handled in various different ways, for 4860 // example, unnamed unions inject all members into the struct namespace! 4861 4862 DeclaratorInfo *DInfo = 0; 4863 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4864 4865 if (BitWidth) { 4866 // 6.7.2.1p3, 6.7.2.1p4 4867 if (VerifyBitField(Loc, II, T, BitWidth)) { 4868 D.setInvalidType(); 4869 DeleteExpr(BitWidth); 4870 BitWidth = 0; 4871 } 4872 } else { 4873 // Not a bitfield. 4874 4875 // validate II. 4876 4877 } 4878 4879 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4880 // than a variably modified type. 4881 if (T->isVariablyModifiedType()) { 4882 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4883 D.setInvalidType(); 4884 } 4885 4886 // Get the visibility (access control) for this ivar. 4887 ObjCIvarDecl::AccessControl ac = 4888 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4889 : ObjCIvarDecl::None; 4890 // Must set ivar's DeclContext to its enclosing interface. 4891 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4892 DeclContext *EnclosingContext; 4893 if (ObjCImplementationDecl *IMPDecl = 4894 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4895 // Case of ivar declared in an implementation. Context is that of its class. 4896 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4897 assert(IDecl && "No class- ActOnIvar"); 4898 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4899 } else 4900 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4901 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4902 4903 // Construct the decl. 4904 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4905 EnclosingContext, Loc, II, T, 4906 DInfo, ac, (Expr *)BitfieldWidth); 4907 4908 if (II) { 4909 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4910 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4911 && !isa<TagDecl>(PrevDecl)) { 4912 Diag(Loc, diag::err_duplicate_member) << II; 4913 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4914 NewID->setInvalidDecl(); 4915 } 4916 } 4917 4918 // Process attributes attached to the ivar. 4919 ProcessDeclAttributes(S, NewID, D); 4920 4921 if (D.isInvalidType()) 4922 NewID->setInvalidDecl(); 4923 4924 if (II) { 4925 // FIXME: When interfaces are DeclContexts, we'll need to add 4926 // these to the interface. 4927 S->AddDecl(DeclPtrTy::make(NewID)); 4928 IdResolver.AddDecl(NewID); 4929 } 4930 4931 return DeclPtrTy::make(NewID); 4932} 4933 4934void Sema::ActOnFields(Scope* S, 4935 SourceLocation RecLoc, DeclPtrTy RecDecl, 4936 DeclPtrTy *Fields, unsigned NumFields, 4937 SourceLocation LBrac, SourceLocation RBrac, 4938 AttributeList *Attr) { 4939 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4940 assert(EnclosingDecl && "missing record or interface decl"); 4941 4942 // If the decl this is being inserted into is invalid, then it may be a 4943 // redeclaration or some other bogus case. Don't try to add fields to it. 4944 if (EnclosingDecl->isInvalidDecl()) { 4945 // FIXME: Deallocate fields? 4946 return; 4947 } 4948 4949 4950 // Verify that all the fields are okay. 4951 unsigned NumNamedMembers = 0; 4952 llvm::SmallVector<FieldDecl*, 32> RecFields; 4953 4954 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4955 for (unsigned i = 0; i != NumFields; ++i) { 4956 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4957 4958 // Get the type for the field. 4959 Type *FDTy = FD->getType().getTypePtr(); 4960 4961 if (!FD->isAnonymousStructOrUnion()) { 4962 // Remember all fields written by the user. 4963 RecFields.push_back(FD); 4964 } 4965 4966 // If the field is already invalid for some reason, don't emit more 4967 // diagnostics about it. 4968 if (FD->isInvalidDecl()) 4969 continue; 4970 4971 // C99 6.7.2.1p2: 4972 // A structure or union shall not contain a member with 4973 // incomplete or function type (hence, a structure shall not 4974 // contain an instance of itself, but may contain a pointer to 4975 // an instance of itself), except that the last member of a 4976 // structure with more than one named member may have incomplete 4977 // array type; such a structure (and any union containing, 4978 // possibly recursively, a member that is such a structure) 4979 // shall not be a member of a structure or an element of an 4980 // array. 4981 if (FDTy->isFunctionType()) { 4982 // Field declared as a function. 4983 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4984 << FD->getDeclName(); 4985 FD->setInvalidDecl(); 4986 EnclosingDecl->setInvalidDecl(); 4987 continue; 4988 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4989 Record && Record->isStruct()) { 4990 // Flexible array member. 4991 if (NumNamedMembers < 1) { 4992 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4993 << FD->getDeclName(); 4994 FD->setInvalidDecl(); 4995 EnclosingDecl->setInvalidDecl(); 4996 continue; 4997 } 4998 // Okay, we have a legal flexible array member at the end of the struct. 4999 if (Record) 5000 Record->setHasFlexibleArrayMember(true); 5001 } else if (!FDTy->isDependentType() && 5002 RequireCompleteType(FD->getLocation(), FD->getType(), 5003 diag::err_field_incomplete)) { 5004 // Incomplete type 5005 FD->setInvalidDecl(); 5006 EnclosingDecl->setInvalidDecl(); 5007 continue; 5008 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5009 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5010 // If this is a member of a union, then entire union becomes "flexible". 5011 if (Record && Record->isUnion()) { 5012 Record->setHasFlexibleArrayMember(true); 5013 } else { 5014 // If this is a struct/class and this is not the last element, reject 5015 // it. Note that GCC supports variable sized arrays in the middle of 5016 // structures. 5017 if (i != NumFields-1) 5018 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5019 << FD->getDeclName() << FD->getType(); 5020 else { 5021 // We support flexible arrays at the end of structs in 5022 // other structs as an extension. 5023 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5024 << FD->getDeclName(); 5025 if (Record) 5026 Record->setHasFlexibleArrayMember(true); 5027 } 5028 } 5029 } 5030 if (Record && FDTTy->getDecl()->hasObjectMember()) 5031 Record->setHasObjectMember(true); 5032 } else if (FDTy->isObjCInterfaceType()) { 5033 /// A field cannot be an Objective-c object 5034 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5035 FD->setInvalidDecl(); 5036 EnclosingDecl->setInvalidDecl(); 5037 continue; 5038 } else if (getLangOptions().ObjC1 && 5039 getLangOptions().getGCMode() != LangOptions::NonGC && 5040 Record && 5041 (FD->getType()->isObjCObjectPointerType() || 5042 FD->getType().isObjCGCStrong())) 5043 Record->setHasObjectMember(true); 5044 // Keep track of the number of named members. 5045 if (FD->getIdentifier()) 5046 ++NumNamedMembers; 5047 } 5048 5049 // Okay, we successfully defined 'Record'. 5050 if (Record) { 5051 Record->completeDefinition(Context); 5052 } else { 5053 ObjCIvarDecl **ClsFields = 5054 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5055 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5056 ID->setIVarList(ClsFields, RecFields.size(), Context); 5057 ID->setLocEnd(RBrac); 5058 // Add ivar's to class's DeclContext. 5059 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5060 ClsFields[i]->setLexicalDeclContext(ID); 5061 ID->addDecl(ClsFields[i]); 5062 } 5063 // Must enforce the rule that ivars in the base classes may not be 5064 // duplicates. 5065 if (ID->getSuperClass()) { 5066 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5067 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5068 ObjCIvarDecl* Ivar = (*IVI); 5069 5070 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5071 ObjCIvarDecl* prevIvar = 5072 ID->getSuperClass()->lookupInstanceVariable(II); 5073 if (prevIvar) { 5074 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5075 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5076 } 5077 } 5078 } 5079 } 5080 } else if (ObjCImplementationDecl *IMPDecl = 5081 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5082 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5083 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5084 // Ivar declared in @implementation never belongs to the implementation. 5085 // Only it is in implementation's lexical context. 5086 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5087 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5088 } 5089 } 5090 5091 if (Attr) 5092 ProcessDeclAttributeList(S, Record, Attr); 5093} 5094 5095EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5096 EnumConstantDecl *LastEnumConst, 5097 SourceLocation IdLoc, 5098 IdentifierInfo *Id, 5099 ExprArg val) { 5100 Expr *Val = (Expr *)val.get(); 5101 5102 llvm::APSInt EnumVal(32); 5103 QualType EltTy; 5104 if (Val && !Val->isTypeDependent()) { 5105 // Make sure to promote the operand type to int. 5106 UsualUnaryConversions(Val); 5107 if (Val != val.get()) { 5108 val.release(); 5109 val = Val; 5110 } 5111 5112 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5113 SourceLocation ExpLoc; 5114 if (!Val->isValueDependent() && 5115 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5116 Val = 0; 5117 } else { 5118 EltTy = Val->getType(); 5119 } 5120 } 5121 5122 if (!Val) { 5123 if (LastEnumConst) { 5124 // Assign the last value + 1. 5125 EnumVal = LastEnumConst->getInitVal(); 5126 ++EnumVal; 5127 5128 // Check for overflow on increment. 5129 if (EnumVal < LastEnumConst->getInitVal()) 5130 Diag(IdLoc, diag::warn_enum_value_overflow); 5131 5132 EltTy = LastEnumConst->getType(); 5133 } else { 5134 // First value, set to zero. 5135 EltTy = Context.IntTy; 5136 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5137 } 5138 } 5139 5140 val.release(); 5141 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5142 Val, EnumVal); 5143} 5144 5145 5146Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5147 DeclPtrTy lastEnumConst, 5148 SourceLocation IdLoc, 5149 IdentifierInfo *Id, 5150 SourceLocation EqualLoc, ExprTy *val) { 5151 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5152 EnumConstantDecl *LastEnumConst = 5153 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5154 Expr *Val = static_cast<Expr*>(val); 5155 5156 // The scope passed in may not be a decl scope. Zip up the scope tree until 5157 // we find one that is. 5158 S = getNonFieldDeclScope(S); 5159 5160 // Verify that there isn't already something declared with this name in this 5161 // scope. 5162 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5163 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5164 // Maybe we will complain about the shadowed template parameter. 5165 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5166 // Just pretend that we didn't see the previous declaration. 5167 PrevDecl = 0; 5168 } 5169 5170 if (PrevDecl) { 5171 // When in C++, we may get a TagDecl with the same name; in this case the 5172 // enum constant will 'hide' the tag. 5173 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5174 "Received TagDecl when not in C++!"); 5175 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5176 if (isa<EnumConstantDecl>(PrevDecl)) 5177 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5178 else 5179 Diag(IdLoc, diag::err_redefinition) << Id; 5180 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5181 if (Val) Val->Destroy(Context); 5182 return DeclPtrTy(); 5183 } 5184 } 5185 5186 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5187 IdLoc, Id, Owned(Val)); 5188 5189 // Register this decl in the current scope stack. 5190 if (New) 5191 PushOnScopeChains(New, S); 5192 5193 return DeclPtrTy::make(New); 5194} 5195 5196void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5197 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5198 DeclPtrTy *Elements, unsigned NumElements, 5199 Scope *S, AttributeList *Attr) { 5200 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5201 QualType EnumType = Context.getTypeDeclType(Enum); 5202 5203 if (Attr) 5204 ProcessDeclAttributeList(S, Enum, Attr); 5205 5206 // TODO: If the result value doesn't fit in an int, it must be a long or long 5207 // long value. ISO C does not support this, but GCC does as an extension, 5208 // emit a warning. 5209 unsigned IntWidth = Context.Target.getIntWidth(); 5210 unsigned CharWidth = Context.Target.getCharWidth(); 5211 unsigned ShortWidth = Context.Target.getShortWidth(); 5212 5213 // Verify that all the values are okay, compute the size of the values, and 5214 // reverse the list. 5215 unsigned NumNegativeBits = 0; 5216 unsigned NumPositiveBits = 0; 5217 5218 // Keep track of whether all elements have type int. 5219 bool AllElementsInt = true; 5220 5221 for (unsigned i = 0; i != NumElements; ++i) { 5222 EnumConstantDecl *ECD = 5223 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5224 if (!ECD) continue; // Already issued a diagnostic. 5225 5226 // If the enum value doesn't fit in an int, emit an extension warning. 5227 const llvm::APSInt &InitVal = ECD->getInitVal(); 5228 assert(InitVal.getBitWidth() >= IntWidth && 5229 "Should have promoted value to int"); 5230 if (InitVal.getBitWidth() > IntWidth) { 5231 llvm::APSInt V(InitVal); 5232 V.trunc(IntWidth); 5233 V.extend(InitVal.getBitWidth()); 5234 if (V != InitVal) 5235 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5236 << InitVal.toString(10); 5237 } 5238 5239 // Keep track of the size of positive and negative values. 5240 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5241 NumPositiveBits = std::max(NumPositiveBits, 5242 (unsigned)InitVal.getActiveBits()); 5243 else 5244 NumNegativeBits = std::max(NumNegativeBits, 5245 (unsigned)InitVal.getMinSignedBits()); 5246 5247 // Keep track of whether every enum element has type int (very commmon). 5248 if (AllElementsInt) 5249 AllElementsInt = ECD->getType() == Context.IntTy; 5250 } 5251 5252 // Figure out the type that should be used for this enum. 5253 // FIXME: Support -fshort-enums. 5254 QualType BestType; 5255 unsigned BestWidth; 5256 5257 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5258 5259 if (NumNegativeBits) { 5260 // If there is a negative value, figure out the smallest integer type (of 5261 // int/long/longlong) that fits. 5262 // If it's packed, check also if it fits a char or a short. 5263 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5264 BestType = Context.SignedCharTy; 5265 BestWidth = CharWidth; 5266 } else if (Packed && NumNegativeBits <= ShortWidth && 5267 NumPositiveBits < ShortWidth) { 5268 BestType = Context.ShortTy; 5269 BestWidth = ShortWidth; 5270 } 5271 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5272 BestType = Context.IntTy; 5273 BestWidth = IntWidth; 5274 } else { 5275 BestWidth = Context.Target.getLongWidth(); 5276 5277 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5278 BestType = Context.LongTy; 5279 else { 5280 BestWidth = Context.Target.getLongLongWidth(); 5281 5282 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5283 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5284 BestType = Context.LongLongTy; 5285 } 5286 } 5287 } else { 5288 // If there is no negative value, figure out which of uint, ulong, ulonglong 5289 // fits. 5290 // If it's packed, check also if it fits a char or a short. 5291 if (Packed && NumPositiveBits <= CharWidth) { 5292 BestType = Context.UnsignedCharTy; 5293 BestWidth = CharWidth; 5294 } else if (Packed && NumPositiveBits <= ShortWidth) { 5295 BestType = Context.UnsignedShortTy; 5296 BestWidth = ShortWidth; 5297 } 5298 else if (NumPositiveBits <= IntWidth) { 5299 BestType = Context.UnsignedIntTy; 5300 BestWidth = IntWidth; 5301 } else if (NumPositiveBits <= 5302 (BestWidth = Context.Target.getLongWidth())) { 5303 BestType = Context.UnsignedLongTy; 5304 } else { 5305 BestWidth = Context.Target.getLongLongWidth(); 5306 assert(NumPositiveBits <= BestWidth && 5307 "How could an initializer get larger than ULL?"); 5308 BestType = Context.UnsignedLongLongTy; 5309 } 5310 } 5311 5312 // Loop over all of the enumerator constants, changing their types to match 5313 // the type of the enum if needed. 5314 for (unsigned i = 0; i != NumElements; ++i) { 5315 EnumConstantDecl *ECD = 5316 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5317 if (!ECD) continue; // Already issued a diagnostic. 5318 5319 // Standard C says the enumerators have int type, but we allow, as an 5320 // extension, the enumerators to be larger than int size. If each 5321 // enumerator value fits in an int, type it as an int, otherwise type it the 5322 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5323 // that X has type 'int', not 'unsigned'. 5324 if (ECD->getType() == Context.IntTy) { 5325 // Make sure the init value is signed. 5326 llvm::APSInt IV = ECD->getInitVal(); 5327 IV.setIsSigned(true); 5328 ECD->setInitVal(IV); 5329 5330 if (getLangOptions().CPlusPlus) 5331 // C++ [dcl.enum]p4: Following the closing brace of an 5332 // enum-specifier, each enumerator has the type of its 5333 // enumeration. 5334 ECD->setType(EnumType); 5335 continue; // Already int type. 5336 } 5337 5338 // Determine whether the value fits into an int. 5339 llvm::APSInt InitVal = ECD->getInitVal(); 5340 bool FitsInInt; 5341 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5342 FitsInInt = InitVal.getActiveBits() < IntWidth; 5343 else 5344 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5345 5346 // If it fits into an integer type, force it. Otherwise force it to match 5347 // the enum decl type. 5348 QualType NewTy; 5349 unsigned NewWidth; 5350 bool NewSign; 5351 if (FitsInInt) { 5352 NewTy = Context.IntTy; 5353 NewWidth = IntWidth; 5354 NewSign = true; 5355 } else if (ECD->getType() == BestType) { 5356 // Already the right type! 5357 if (getLangOptions().CPlusPlus) 5358 // C++ [dcl.enum]p4: Following the closing brace of an 5359 // enum-specifier, each enumerator has the type of its 5360 // enumeration. 5361 ECD->setType(EnumType); 5362 continue; 5363 } else { 5364 NewTy = BestType; 5365 NewWidth = BestWidth; 5366 NewSign = BestType->isSignedIntegerType(); 5367 } 5368 5369 // Adjust the APSInt value. 5370 InitVal.extOrTrunc(NewWidth); 5371 InitVal.setIsSigned(NewSign); 5372 ECD->setInitVal(InitVal); 5373 5374 // Adjust the Expr initializer and type. 5375 if (ECD->getInitExpr()) 5376 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5377 CastExpr::CK_Unknown, 5378 ECD->getInitExpr(), 5379 /*isLvalue=*/false)); 5380 if (getLangOptions().CPlusPlus) 5381 // C++ [dcl.enum]p4: Following the closing brace of an 5382 // enum-specifier, each enumerator has the type of its 5383 // enumeration. 5384 ECD->setType(EnumType); 5385 else 5386 ECD->setType(NewTy); 5387 } 5388 5389 Enum->completeDefinition(Context, BestType); 5390} 5391 5392Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5393 ExprArg expr) { 5394 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5395 5396 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5397 Loc, AsmString); 5398 CurContext->addDecl(New); 5399 return DeclPtrTy::make(New); 5400} 5401 5402void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5403 SourceLocation PragmaLoc, 5404 SourceLocation NameLoc) { 5405 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5406 5407 if (PrevDecl) { 5408 PrevDecl->addAttr(::new (Context) WeakAttr()); 5409 } else { 5410 (void)WeakUndeclaredIdentifiers.insert( 5411 std::pair<IdentifierInfo*,WeakInfo> 5412 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5413 } 5414} 5415 5416void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5417 IdentifierInfo* AliasName, 5418 SourceLocation PragmaLoc, 5419 SourceLocation NameLoc, 5420 SourceLocation AliasNameLoc) { 5421 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5422 WeakInfo W = WeakInfo(Name, NameLoc); 5423 5424 if (PrevDecl) { 5425 if (!PrevDecl->hasAttr<AliasAttr>()) 5426 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5427 DeclApplyPragmaWeak(TUScope, ND, W); 5428 } else { 5429 (void)WeakUndeclaredIdentifiers.insert( 5430 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5431 } 5432} 5433