SemaDecl.cpp revision dd8e0065207e953bb28b95ad9cb6b2c13f56b3b8
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 "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/Parse/DeclSpec.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31using namespace clang; 32 33/// \brief If the identifier refers to a type name within this scope, 34/// return the declaration of that type. 35/// 36/// This routine performs ordinary name lookup of the identifier II 37/// within the given scope, with optional C++ scope specifier SS, to 38/// determine whether the name refers to a type. If so, returns an 39/// opaque pointer (actually a QualType) corresponding to that 40/// type. Otherwise, returns NULL. 41/// 42/// If name lookup results in an ambiguity, this routine will complain 43/// and then return NULL. 44Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 45 Scope *S, const CXXScopeSpec *SS) { 46 NamedDecl *IIDecl = 0; 47 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 48 false, false); 49 switch (Result.getKind()) { 50 case LookupResult::NotFound: 51 case LookupResult::FoundOverloaded: 52 return 0; 53 54 case LookupResult::AmbiguousBaseSubobjectTypes: 55 case LookupResult::AmbiguousBaseSubobjects: 56 case LookupResult::AmbiguousReference: 57 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 58 return 0; 59 60 case LookupResult::Found: 61 IIDecl = Result.getAsDecl(); 62 break; 63 } 64 65 if (IIDecl) { 66 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 67 // Check whether we can use this type 68 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 69 70 return Context.getTypeDeclType(TD).getAsOpaquePtr(); 71 } 72 73 if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 74 // Check whether we can use this interface. 75 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 76 77 return Context.getObjCInterfaceType(IDecl).getAsOpaquePtr(); 78 } 79 80 // Otherwise, could be a variable, function etc. 81 } 82 return 0; 83} 84 85DeclContext *Sema::getContainingDC(DeclContext *DC) { 86 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 87 // A C++ out-of-line method will return to the file declaration context. 88 if (MD->isOutOfLineDefinition()) 89 return MD->getLexicalDeclContext(); 90 91 // A C++ inline method is parsed *after* the topmost class it was declared 92 // in is fully parsed (it's "complete"). 93 // The parsing of a C++ inline method happens at the declaration context of 94 // the topmost (non-nested) class it is lexically declared in. 95 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 96 DC = MD->getParent(); 97 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 98 DC = RD; 99 100 // Return the declaration context of the topmost class the inline method is 101 // declared in. 102 return DC; 103 } 104 105 if (isa<ObjCMethodDecl>(DC)) 106 return Context.getTranslationUnitDecl(); 107 108 return DC->getLexicalParent(); 109} 110 111void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 112 assert(getContainingDC(DC) == CurContext && 113 "The next DeclContext should be lexically contained in the current one."); 114 CurContext = DC; 115 S->setEntity(DC); 116} 117 118void Sema::PopDeclContext() { 119 assert(CurContext && "DeclContext imbalance!"); 120 121 CurContext = getContainingDC(CurContext); 122} 123 124/// \brief Determine whether we allow overloading of the function 125/// PrevDecl with another declaration. 126/// 127/// This routine determines whether overloading is possible, not 128/// whether some new function is actually an overload. It will return 129/// true in C++ (where we can always provide overloads) or, as an 130/// extension, in C when the previous function is already an 131/// overloaded function declaration or has the "overloadable" 132/// attribute. 133static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 134 if (Context.getLangOptions().CPlusPlus) 135 return true; 136 137 if (isa<OverloadedFunctionDecl>(PrevDecl)) 138 return true; 139 140 return PrevDecl->getAttr<OverloadableAttr>() != 0; 141} 142 143/// Add this decl to the scope shadowed decl chains. 144void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 145 // Move up the scope chain until we find the nearest enclosing 146 // non-transparent context. The declaration will be introduced into this 147 // scope. 148 while (S->getEntity() && 149 ((DeclContext *)S->getEntity())->isTransparentContext()) 150 S = S->getParent(); 151 152 S->AddDecl(D); 153 154 // Add scoped declarations into their context, so that they can be 155 // found later. Declarations without a context won't be inserted 156 // into any context. 157 CurContext->addDecl(D); 158 159 // C++ [basic.scope]p4: 160 // -- exactly one declaration shall declare a class name or 161 // enumeration name that is not a typedef name and the other 162 // declarations shall all refer to the same object or 163 // enumerator, or all refer to functions and function templates; 164 // in this case the class name or enumeration name is hidden. 165 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 166 // We are pushing the name of a tag (enum or class). 167 if (CurContext->getLookupContext() 168 == TD->getDeclContext()->getLookupContext()) { 169 // We're pushing the tag into the current context, which might 170 // require some reshuffling in the identifier resolver. 171 IdentifierResolver::iterator 172 I = IdResolver.begin(TD->getDeclName()), 173 IEnd = IdResolver.end(); 174 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 175 NamedDecl *PrevDecl = *I; 176 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 177 PrevDecl = *I, ++I) { 178 if (TD->declarationReplaces(*I)) { 179 // This is a redeclaration. Remove it from the chain and 180 // break out, so that we'll add in the shadowed 181 // declaration. 182 S->RemoveDecl(*I); 183 if (PrevDecl == *I) { 184 IdResolver.RemoveDecl(*I); 185 IdResolver.AddDecl(TD); 186 return; 187 } else { 188 IdResolver.RemoveDecl(*I); 189 break; 190 } 191 } 192 } 193 194 // There is already a declaration with the same name in the same 195 // scope, which is not a tag declaration. It must be found 196 // before we find the new declaration, so insert the new 197 // declaration at the end of the chain. 198 IdResolver.AddShadowedDecl(TD, PrevDecl); 199 200 return; 201 } 202 } 203 } else if (isa<FunctionDecl>(D) && 204 AllowOverloadingOfFunction(D, Context)) { 205 // We are pushing the name of a function, which might be an 206 // overloaded name. 207 FunctionDecl *FD = cast<FunctionDecl>(D); 208 IdentifierResolver::iterator Redecl 209 = std::find_if(IdResolver.begin(FD->getDeclName()), 210 IdResolver.end(), 211 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 212 FD)); 213 if (Redecl != IdResolver.end() && S->isDeclScope(*Redecl)) { 214 // There is already a declaration of a function on our 215 // IdResolver chain. Replace it with this declaration. 216 S->RemoveDecl(*Redecl); 217 IdResolver.RemoveDecl(*Redecl); 218 } 219 } 220 221 IdResolver.AddDecl(D); 222} 223 224void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 225 if (S->decl_empty()) return; 226 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 227 "Scope shouldn't contain decls!"); 228 229 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 230 I != E; ++I) { 231 Decl *TmpD = static_cast<Decl*>(*I); 232 assert(TmpD && "This decl didn't get pushed??"); 233 234 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 235 NamedDecl *D = cast<NamedDecl>(TmpD); 236 237 if (!D->getDeclName()) continue; 238 239 // Remove this name from our lexical scope. 240 IdResolver.RemoveDecl(D); 241 } 242} 243 244/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 245/// return 0 if one not found. 246ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 247 // The third "scope" argument is 0 since we aren't enabling lazy built-in 248 // creation from this context. 249 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 250 251 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 252} 253 254/// getNonFieldDeclScope - Retrieves the innermost scope, starting 255/// from S, where a non-field would be declared. This routine copes 256/// with the difference between C and C++ scoping rules in structs and 257/// unions. For example, the following code is well-formed in C but 258/// ill-formed in C++: 259/// @code 260/// struct S6 { 261/// enum { BAR } e; 262/// }; 263/// 264/// void test_S6() { 265/// struct S6 a; 266/// a.e = BAR; 267/// } 268/// @endcode 269/// For the declaration of BAR, this routine will return a different 270/// scope. The scope S will be the scope of the unnamed enumeration 271/// within S6. In C++, this routine will return the scope associated 272/// with S6, because the enumeration's scope is a transparent 273/// context but structures can contain non-field names. In C, this 274/// routine will return the translation unit scope, since the 275/// enumeration's scope is a transparent context and structures cannot 276/// contain non-field names. 277Scope *Sema::getNonFieldDeclScope(Scope *S) { 278 while (((S->getFlags() & Scope::DeclScope) == 0) || 279 (S->getEntity() && 280 ((DeclContext *)S->getEntity())->isTransparentContext()) || 281 (S->isClassScope() && !getLangOptions().CPlusPlus)) 282 S = S->getParent(); 283 return S; 284} 285 286void Sema::InitBuiltinVaListType() { 287 if (!Context.getBuiltinVaListType().isNull()) 288 return; 289 290 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 291 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 292 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 293 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 294} 295 296/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 297/// file scope. lazily create a decl for it. ForRedeclaration is true 298/// if we're creating this built-in in anticipation of redeclaring the 299/// built-in. 300NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 301 Scope *S, bool ForRedeclaration, 302 SourceLocation Loc) { 303 Builtin::ID BID = (Builtin::ID)bid; 304 305 if (Context.BuiltinInfo.hasVAListUse(BID)) 306 InitBuiltinVaListType(); 307 308 Builtin::Context::GetBuiltinTypeError Error; 309 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 310 switch (Error) { 311 case Builtin::Context::GE_None: 312 // Okay 313 break; 314 315 case Builtin::Context::GE_Missing_FILE: 316 if (ForRedeclaration) 317 Diag(Loc, diag::err_implicit_decl_requires_stdio) 318 << Context.BuiltinInfo.GetName(BID); 319 return 0; 320 } 321 322 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 323 Diag(Loc, diag::ext_implicit_lib_function_decl) 324 << Context.BuiltinInfo.GetName(BID) 325 << R; 326 if (Context.BuiltinInfo.getHeaderName(BID) && 327 Diags.getDiagnosticMapping(diag::ext_implicit_lib_function_decl) 328 != diag::MAP_IGNORE) 329 Diag(Loc, diag::note_please_include_header) 330 << Context.BuiltinInfo.getHeaderName(BID) 331 << Context.BuiltinInfo.GetName(BID); 332 } 333 334 FunctionDecl *New = FunctionDecl::Create(Context, 335 Context.getTranslationUnitDecl(), 336 Loc, II, R, 337 FunctionDecl::Extern, false); 338 New->setImplicit(); 339 340 // Create Decl objects for each parameter, adding them to the 341 // FunctionDecl. 342 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 343 llvm::SmallVector<ParmVarDecl*, 16> Params; 344 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 345 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 346 FT->getArgType(i), VarDecl::None, 0)); 347 New->setParams(Context, &Params[0], Params.size()); 348 } 349 350 AddKnownFunctionAttributes(New); 351 352 // TUScope is the translation-unit scope to insert this function into. 353 // FIXME: This is hideous. We need to teach PushOnScopeChains to 354 // relate Scopes to DeclContexts, and probably eliminate CurContext 355 // entirely, but we're not there yet. 356 DeclContext *SavedContext = CurContext; 357 CurContext = Context.getTranslationUnitDecl(); 358 PushOnScopeChains(New, TUScope); 359 CurContext = SavedContext; 360 return New; 361} 362 363/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 364/// everything from the standard library is defined. 365NamespaceDecl *Sema::GetStdNamespace() { 366 if (!StdNamespace) { 367 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 368 DeclContext *Global = Context.getTranslationUnitDecl(); 369 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 370 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 371 } 372 return StdNamespace; 373} 374 375/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 376/// same name and scope as a previous declaration 'Old'. Figure out 377/// how to resolve this situation, merging decls or emitting 378/// diagnostics as appropriate. Returns true if there was an error, 379/// false otherwise. 380/// 381bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 382 bool objc_types = false; 383 // Allow multiple definitions for ObjC built-in typedefs. 384 // FIXME: Verify the underlying types are equivalent! 385 if (getLangOptions().ObjC1) { 386 const IdentifierInfo *TypeID = New->getIdentifier(); 387 switch (TypeID->getLength()) { 388 default: break; 389 case 2: 390 if (!TypeID->isStr("id")) 391 break; 392 Context.setObjCIdType(New); 393 objc_types = true; 394 break; 395 case 5: 396 if (!TypeID->isStr("Class")) 397 break; 398 Context.setObjCClassType(New); 399 objc_types = true; 400 return false; 401 case 3: 402 if (!TypeID->isStr("SEL")) 403 break; 404 Context.setObjCSelType(New); 405 objc_types = true; 406 return false; 407 case 8: 408 if (!TypeID->isStr("Protocol")) 409 break; 410 Context.setObjCProtoType(New->getUnderlyingType()); 411 objc_types = true; 412 return false; 413 } 414 // Fall through - the typedef name was not a builtin type. 415 } 416 // Verify the old decl was also a type. 417 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 418 if (!Old) { 419 Diag(New->getLocation(), diag::err_redefinition_different_kind) 420 << New->getDeclName(); 421 if (!objc_types) 422 Diag(OldD->getLocation(), diag::note_previous_definition); 423 return true; 424 } 425 426 // Determine the "old" type we'll use for checking and diagnostics. 427 QualType OldType; 428 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 429 OldType = OldTypedef->getUnderlyingType(); 430 else 431 OldType = Context.getTypeDeclType(Old); 432 433 // If the typedef types are not identical, reject them in all languages and 434 // with any extensions enabled. 435 436 if (OldType != New->getUnderlyingType() && 437 Context.getCanonicalType(OldType) != 438 Context.getCanonicalType(New->getUnderlyingType())) { 439 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 440 << New->getUnderlyingType() << OldType; 441 if (!objc_types) 442 Diag(Old->getLocation(), diag::note_previous_definition); 443 return true; 444 } 445 if (objc_types) return false; 446 if (getLangOptions().Microsoft) return false; 447 448 // C++ [dcl.typedef]p2: 449 // In a given non-class scope, a typedef specifier can be used to 450 // redefine the name of any type declared in that scope to refer 451 // to the type to which it already refers. 452 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 453 return false; 454 455 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 456 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 457 // *either* declaration is in a system header. The code below implements 458 // this adhoc compatibility rule. FIXME: The following code will not 459 // work properly when compiling ".i" files (containing preprocessed output). 460 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 461 SourceManager &SrcMgr = Context.getSourceManager(); 462 if (SrcMgr.isInSystemHeader(Old->getLocation())) 463 return false; 464 if (SrcMgr.isInSystemHeader(New->getLocation())) 465 return false; 466 } 467 468 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 469 Diag(Old->getLocation(), diag::note_previous_definition); 470 return true; 471} 472 473/// DeclhasAttr - returns true if decl Declaration already has the target 474/// attribute. 475static bool DeclHasAttr(const Decl *decl, const Attr *target) { 476 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 477 if (attr->getKind() == target->getKind()) 478 return true; 479 480 return false; 481} 482 483/// MergeAttributes - append attributes from the Old decl to the New one. 484static void MergeAttributes(Decl *New, Decl *Old) { 485 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 486 487 while (attr) { 488 tmp = attr; 489 attr = attr->getNext(); 490 491 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 492 tmp->setInherited(true); 493 New->addAttr(tmp); 494 } else { 495 tmp->setNext(0); 496 delete(tmp); 497 } 498 } 499 500 Old->invalidateAttrs(); 501} 502 503/// MergeFunctionDecl - We just parsed a function 'New' from 504/// declarator D which has the same name and scope as a previous 505/// declaration 'Old'. Figure out how to resolve this situation, 506/// merging decls or emitting diagnostics as appropriate. 507/// 508/// In C++, New and Old must be declarations that are not 509/// overloaded. Use IsOverload to determine whether New and Old are 510/// overloaded, and to select the Old declaration that New should be 511/// merged with. 512/// 513/// Returns true if there was an error, false otherwise. 514bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 515 assert(!isa<OverloadedFunctionDecl>(OldD) && 516 "Cannot merge with an overloaded function declaration"); 517 518 // Verify the old decl was also a function. 519 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 520 if (!Old) { 521 Diag(New->getLocation(), diag::err_redefinition_different_kind) 522 << New->getDeclName(); 523 Diag(OldD->getLocation(), diag::note_previous_definition); 524 return true; 525 } 526 527 // Determine whether the previous declaration was a definition, 528 // implicit declaration, or a declaration. 529 diag::kind PrevDiag; 530 if (Old->isThisDeclarationADefinition()) 531 PrevDiag = diag::note_previous_definition; 532 else if (Old->isImplicit()) 533 PrevDiag = diag::note_previous_implicit_declaration; 534 else 535 PrevDiag = diag::note_previous_declaration; 536 537 QualType OldQType = Context.getCanonicalType(Old->getType()); 538 QualType NewQType = Context.getCanonicalType(New->getType()); 539 540 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 541 New->getStorageClass() == FunctionDecl::Static && 542 Old->getStorageClass() != FunctionDecl::Static) { 543 Diag(New->getLocation(), diag::err_static_non_static) 544 << New; 545 Diag(Old->getLocation(), PrevDiag); 546 return true; 547 } 548 549 if (getLangOptions().CPlusPlus) { 550 // (C++98 13.1p2): 551 // Certain function declarations cannot be overloaded: 552 // -- Function declarations that differ only in the return type 553 // cannot be overloaded. 554 QualType OldReturnType 555 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 556 QualType NewReturnType 557 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 558 if (OldReturnType != NewReturnType) { 559 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 560 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 561 return true; 562 } 563 564 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 565 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 566 if (OldMethod && NewMethod) { 567 // -- Member function declarations with the same name and the 568 // same parameter types cannot be overloaded if any of them 569 // is a static member function declaration. 570 if (OldMethod->isStatic() || NewMethod->isStatic()) { 571 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 572 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 573 return true; 574 } 575 576 // C++ [class.mem]p1: 577 // [...] A member shall not be declared twice in the 578 // member-specification, except that a nested class or member 579 // class template can be declared and then later defined. 580 if (OldMethod->getLexicalDeclContext() == 581 NewMethod->getLexicalDeclContext()) { 582 unsigned NewDiag; 583 if (isa<CXXConstructorDecl>(OldMethod)) 584 NewDiag = diag::err_constructor_redeclared; 585 else if (isa<CXXDestructorDecl>(NewMethod)) 586 NewDiag = diag::err_destructor_redeclared; 587 else if (isa<CXXConversionDecl>(NewMethod)) 588 NewDiag = diag::err_conv_function_redeclared; 589 else 590 NewDiag = diag::err_member_redeclared; 591 592 Diag(New->getLocation(), NewDiag); 593 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 594 } 595 } 596 597 // (C++98 8.3.5p3): 598 // All declarations for a function shall agree exactly in both the 599 // return type and the parameter-type-list. 600 if (OldQType == NewQType) 601 return MergeCompatibleFunctionDecls(New, Old); 602 603 // Fall through for conflicting redeclarations and redefinitions. 604 } 605 606 // C: Function types need to be compatible, not identical. This handles 607 // duplicate function decls like "void f(int); void f(enum X);" properly. 608 if (!getLangOptions().CPlusPlus && 609 Context.typesAreCompatible(OldQType, NewQType)) { 610 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 611 const FunctionTypeProto *OldProto = 0; 612 if (isa<FunctionTypeNoProto>(NewFuncType) && 613 (OldProto = OldQType->getAsFunctionTypeProto())) { 614 // The old declaration provided a function prototype, but the 615 // new declaration does not. Merge in the prototype. 616 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 617 OldProto->arg_type_end()); 618 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 619 &ParamTypes[0], ParamTypes.size(), 620 OldProto->isVariadic(), 621 OldProto->getTypeQuals()); 622 New->setType(NewQType); 623 New->setInheritedPrototype(); 624 625 // Synthesize a parameter for each argument type. 626 llvm::SmallVector<ParmVarDecl*, 16> Params; 627 for (FunctionTypeProto::arg_type_iterator 628 ParamType = OldProto->arg_type_begin(), 629 ParamEnd = OldProto->arg_type_end(); 630 ParamType != ParamEnd; ++ParamType) { 631 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 632 SourceLocation(), 0, 633 *ParamType, VarDecl::None, 634 0); 635 Param->setImplicit(); 636 Params.push_back(Param); 637 } 638 639 New->setParams(Context, &Params[0], Params.size()); 640 641 } 642 643 return MergeCompatibleFunctionDecls(New, Old); 644 } 645 646 // A function that has already been declared has been redeclared or defined 647 // with a different type- show appropriate diagnostic 648 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 649 // The user has declared a builtin function with an incompatible 650 // signature. 651 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 652 // The function the user is redeclaring is a library-defined 653 // function like 'malloc' or 'printf'. Warn about the 654 // redeclaration, then ignore it. 655 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 656 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 657 << Old << Old->getType(); 658 return true; 659 } 660 661 PrevDiag = diag::note_previous_builtin_declaration; 662 } 663 664 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 665 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 666 return true; 667} 668 669/// \brief Completes the merge of two function declarations that are 670/// known to be compatible. 671/// 672/// This routine handles the merging of attributes and other 673/// properties of function declarations form the old declaration to 674/// the new declaration, once we know that New is in fact a 675/// redeclaration of Old. 676/// 677/// \returns false 678bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 679 // Merge the attributes 680 MergeAttributes(New, Old); 681 682 // Merge the storage class. 683 New->setStorageClass(Old->getStorageClass()); 684 685 // FIXME: need to implement inline semantics 686 687 // Merge "pure" flag. 688 if (Old->isPure()) 689 New->setPure(); 690 691 // Merge the "deleted" flag. 692 if (Old->isDeleted()) 693 New->setDeleted(); 694 695 if (getLangOptions().CPlusPlus) 696 return MergeCXXFunctionDecl(New, Old); 697 698 return false; 699} 700 701/// Predicate for C "tentative" external object definitions (C99 6.9.2). 702static bool isTentativeDefinition(VarDecl *VD) { 703 if (VD->isFileVarDecl()) 704 return (!VD->getInit() && 705 (VD->getStorageClass() == VarDecl::None || 706 VD->getStorageClass() == VarDecl::Static)); 707 return false; 708} 709 710/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 711/// when dealing with C "tentative" external object definitions (C99 6.9.2). 712void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 713 bool VDIsTentative = isTentativeDefinition(VD); 714 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 715 716 // FIXME: I don't think this will actually see all of the 717 // redefinitions. Can't we check this property on-the-fly? 718 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 719 E = IdResolver.end(); 720 I != E; ++I) { 721 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 722 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 723 724 // Handle the following case: 725 // int a[10]; 726 // int a[]; - the code below makes sure we set the correct type. 727 // int a[11]; - this is an error, size isn't 10. 728 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 729 OldDecl->getType()->isConstantArrayType()) 730 VD->setType(OldDecl->getType()); 731 732 // Check for "tentative" definitions. We can't accomplish this in 733 // MergeVarDecl since the initializer hasn't been attached. 734 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 735 continue; 736 737 // Handle __private_extern__ just like extern. 738 if (OldDecl->getStorageClass() != VarDecl::Extern && 739 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 740 VD->getStorageClass() != VarDecl::Extern && 741 VD->getStorageClass() != VarDecl::PrivateExtern) { 742 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 743 Diag(OldDecl->getLocation(), diag::note_previous_definition); 744 // One redefinition error is enough. 745 break; 746 } 747 } 748 } 749} 750 751/// MergeVarDecl - We just parsed a variable 'New' which has the same name 752/// and scope as a previous declaration 'Old'. Figure out how to resolve this 753/// situation, merging decls or emitting diagnostics as appropriate. 754/// 755/// Tentative definition rules (C99 6.9.2p2) are checked by 756/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 757/// definitions here, since the initializer hasn't been attached. 758/// 759bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 760 // Verify the old decl was also a variable. 761 VarDecl *Old = dyn_cast<VarDecl>(OldD); 762 if (!Old) { 763 Diag(New->getLocation(), diag::err_redefinition_different_kind) 764 << New->getDeclName(); 765 Diag(OldD->getLocation(), diag::note_previous_definition); 766 return true; 767 } 768 769 MergeAttributes(New, Old); 770 771 // Merge the types 772 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 773 if (MergedT.isNull()) { 774 Diag(New->getLocation(), diag::err_redefinition_different_type) 775 << New->getDeclName(); 776 Diag(Old->getLocation(), diag::note_previous_definition); 777 return true; 778 } 779 New->setType(MergedT); 780 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 781 if (New->getStorageClass() == VarDecl::Static && 782 (Old->getStorageClass() == VarDecl::None || 783 Old->getStorageClass() == VarDecl::Extern)) { 784 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 785 Diag(Old->getLocation(), diag::note_previous_definition); 786 return true; 787 } 788 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 789 if (New->getStorageClass() != VarDecl::Static && 790 Old->getStorageClass() == VarDecl::Static) { 791 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 792 Diag(Old->getLocation(), diag::note_previous_definition); 793 return true; 794 } 795 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 796 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 797 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 798 Diag(Old->getLocation(), diag::note_previous_definition); 799 return true; 800 } 801 return false; 802} 803 804/// CheckParmsForFunctionDef - Check that the parameters of the given 805/// function are appropriate for the definition of a function. This 806/// takes care of any checks that cannot be performed on the 807/// declaration itself, e.g., that the types of each of the function 808/// parameters are complete. 809bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 810 bool HasInvalidParm = false; 811 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 812 ParmVarDecl *Param = FD->getParamDecl(p); 813 814 // C99 6.7.5.3p4: the parameters in a parameter type list in a 815 // function declarator that is part of a function definition of 816 // that function shall not have incomplete type. 817 if (!Param->isInvalidDecl() && 818 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 819 diag::err_typecheck_decl_incomplete_type)) { 820 Param->setInvalidDecl(); 821 HasInvalidParm = true; 822 } 823 824 // C99 6.9.1p5: If the declarator includes a parameter type list, the 825 // declaration of each parameter shall include an identifier. 826 if (Param->getIdentifier() == 0 && 827 !Param->isImplicit() && 828 !getLangOptions().CPlusPlus) 829 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 830 } 831 832 return HasInvalidParm; 833} 834 835/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 836/// no declarator (e.g. "struct foo;") is parsed. 837Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 838 TagDecl *Tag = 0; 839 if (DS.getTypeSpecType() == DeclSpec::TST_class || 840 DS.getTypeSpecType() == DeclSpec::TST_struct || 841 DS.getTypeSpecType() == DeclSpec::TST_union || 842 DS.getTypeSpecType() == DeclSpec::TST_enum) 843 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 844 845 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 846 if (!Record->getDeclName() && Record->isDefinition() && 847 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 848 return BuildAnonymousStructOrUnion(S, DS, Record); 849 850 // Microsoft allows unnamed struct/union fields. Don't complain 851 // about them. 852 // FIXME: Should we support Microsoft's extensions in this area? 853 if (Record->getDeclName() && getLangOptions().Microsoft) 854 return Tag; 855 } 856 857 if (!DS.isMissingDeclaratorOk() && 858 DS.getTypeSpecType() != DeclSpec::TST_error) { 859 // Warn about typedefs of enums without names, since this is an 860 // extension in both Microsoft an GNU. 861 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 862 Tag && isa<EnumDecl>(Tag)) { 863 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 864 << DS.getSourceRange(); 865 return Tag; 866 } 867 868 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 869 << DS.getSourceRange(); 870 return 0; 871 } 872 873 return Tag; 874} 875 876/// InjectAnonymousStructOrUnionMembers - Inject the members of the 877/// anonymous struct or union AnonRecord into the owning context Owner 878/// and scope S. This routine will be invoked just after we realize 879/// that an unnamed union or struct is actually an anonymous union or 880/// struct, e.g., 881/// 882/// @code 883/// union { 884/// int i; 885/// float f; 886/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 887/// // f into the surrounding scope.x 888/// @endcode 889/// 890/// This routine is recursive, injecting the names of nested anonymous 891/// structs/unions into the owning context and scope as well. 892bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 893 RecordDecl *AnonRecord) { 894 bool Invalid = false; 895 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 896 FEnd = AnonRecord->field_end(); 897 F != FEnd; ++F) { 898 if ((*F)->getDeclName()) { 899 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 900 LookupOrdinaryName, true); 901 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 902 // C++ [class.union]p2: 903 // The names of the members of an anonymous union shall be 904 // distinct from the names of any other entity in the 905 // scope in which the anonymous union is declared. 906 unsigned diagKind 907 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 908 : diag::err_anonymous_struct_member_redecl; 909 Diag((*F)->getLocation(), diagKind) 910 << (*F)->getDeclName(); 911 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 912 Invalid = true; 913 } else { 914 // C++ [class.union]p2: 915 // For the purpose of name lookup, after the anonymous union 916 // definition, the members of the anonymous union are 917 // considered to have been defined in the scope in which the 918 // anonymous union is declared. 919 Owner->makeDeclVisibleInContext(*F); 920 S->AddDecl(*F); 921 IdResolver.AddDecl(*F); 922 } 923 } else if (const RecordType *InnerRecordType 924 = (*F)->getType()->getAsRecordType()) { 925 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 926 if (InnerRecord->isAnonymousStructOrUnion()) 927 Invalid = Invalid || 928 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 929 } 930 } 931 932 return Invalid; 933} 934 935/// ActOnAnonymousStructOrUnion - Handle the declaration of an 936/// anonymous structure or union. Anonymous unions are a C++ feature 937/// (C++ [class.union]) and a GNU C extension; anonymous structures 938/// are a GNU C and GNU C++ extension. 939Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 940 RecordDecl *Record) { 941 DeclContext *Owner = Record->getDeclContext(); 942 943 // Diagnose whether this anonymous struct/union is an extension. 944 if (Record->isUnion() && !getLangOptions().CPlusPlus) 945 Diag(Record->getLocation(), diag::ext_anonymous_union); 946 else if (!Record->isUnion()) 947 Diag(Record->getLocation(), diag::ext_anonymous_struct); 948 949 // C and C++ require different kinds of checks for anonymous 950 // structs/unions. 951 bool Invalid = false; 952 if (getLangOptions().CPlusPlus) { 953 const char* PrevSpec = 0; 954 // C++ [class.union]p3: 955 // Anonymous unions declared in a named namespace or in the 956 // global namespace shall be declared static. 957 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 958 (isa<TranslationUnitDecl>(Owner) || 959 (isa<NamespaceDecl>(Owner) && 960 cast<NamespaceDecl>(Owner)->getDeclName()))) { 961 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 962 Invalid = true; 963 964 // Recover by adding 'static'. 965 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 966 } 967 // C++ [class.union]p3: 968 // A storage class is not allowed in a declaration of an 969 // anonymous union in a class scope. 970 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 971 isa<RecordDecl>(Owner)) { 972 Diag(DS.getStorageClassSpecLoc(), 973 diag::err_anonymous_union_with_storage_spec); 974 Invalid = true; 975 976 // Recover by removing the storage specifier. 977 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 978 PrevSpec); 979 } 980 981 // C++ [class.union]p2: 982 // The member-specification of an anonymous union shall only 983 // define non-static data members. [Note: nested types and 984 // functions cannot be declared within an anonymous union. ] 985 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 986 MemEnd = Record->decls_end(); 987 Mem != MemEnd; ++Mem) { 988 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 989 // C++ [class.union]p3: 990 // An anonymous union shall not have private or protected 991 // members (clause 11). 992 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 993 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 994 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 995 Invalid = true; 996 } 997 } else if ((*Mem)->isImplicit()) { 998 // Any implicit members are fine. 999 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1000 // This is a type that showed up in an 1001 // elaborated-type-specifier inside the anonymous struct or 1002 // union, but which actually declares a type outside of the 1003 // anonymous struct or union. It's okay. 1004 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1005 if (!MemRecord->isAnonymousStructOrUnion() && 1006 MemRecord->getDeclName()) { 1007 // This is a nested type declaration. 1008 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1009 << (int)Record->isUnion(); 1010 Invalid = true; 1011 } 1012 } else { 1013 // We have something that isn't a non-static data 1014 // member. Complain about it. 1015 unsigned DK = diag::err_anonymous_record_bad_member; 1016 if (isa<TypeDecl>(*Mem)) 1017 DK = diag::err_anonymous_record_with_type; 1018 else if (isa<FunctionDecl>(*Mem)) 1019 DK = diag::err_anonymous_record_with_function; 1020 else if (isa<VarDecl>(*Mem)) 1021 DK = diag::err_anonymous_record_with_static; 1022 Diag((*Mem)->getLocation(), DK) 1023 << (int)Record->isUnion(); 1024 Invalid = true; 1025 } 1026 } 1027 } else { 1028 // FIXME: Check GNU C semantics 1029 if (Record->isUnion() && !Owner->isRecord()) { 1030 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 1031 << (int)getLangOptions().CPlusPlus; 1032 Invalid = true; 1033 } 1034 } 1035 1036 if (!Record->isUnion() && !Owner->isRecord()) { 1037 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1038 << (int)getLangOptions().CPlusPlus; 1039 Invalid = true; 1040 } 1041 1042 // Create a declaration for this anonymous struct/union. 1043 NamedDecl *Anon = 0; 1044 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1045 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1046 /*IdentifierInfo=*/0, 1047 Context.getTypeDeclType(Record), 1048 /*BitWidth=*/0, /*Mutable=*/false); 1049 Anon->setAccess(AS_public); 1050 if (getLangOptions().CPlusPlus) 1051 FieldCollector->Add(cast<FieldDecl>(Anon)); 1052 } else { 1053 VarDecl::StorageClass SC; 1054 switch (DS.getStorageClassSpec()) { 1055 default: assert(0 && "Unknown storage class!"); 1056 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1057 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1058 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1059 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1060 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1061 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1062 case DeclSpec::SCS_mutable: 1063 // mutable can only appear on non-static class members, so it's always 1064 // an error here 1065 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1066 Invalid = true; 1067 SC = VarDecl::None; 1068 break; 1069 } 1070 1071 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1072 /*IdentifierInfo=*/0, 1073 Context.getTypeDeclType(Record), 1074 SC, DS.getSourceRange().getBegin()); 1075 } 1076 Anon->setImplicit(); 1077 1078 // Add the anonymous struct/union object to the current 1079 // context. We'll be referencing this object when we refer to one of 1080 // its members. 1081 Owner->addDecl(Anon); 1082 1083 // Inject the members of the anonymous struct/union into the owning 1084 // context and into the identifier resolver chain for name lookup 1085 // purposes. 1086 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1087 Invalid = true; 1088 1089 // Mark this as an anonymous struct/union type. Note that we do not 1090 // do this until after we have already checked and injected the 1091 // members of this anonymous struct/union type, because otherwise 1092 // the members could be injected twice: once by DeclContext when it 1093 // builds its lookup table, and once by 1094 // InjectAnonymousStructOrUnionMembers. 1095 Record->setAnonymousStructOrUnion(true); 1096 1097 if (Invalid) 1098 Anon->setInvalidDecl(); 1099 1100 return Anon; 1101} 1102 1103 1104/// GetNameForDeclarator - Determine the full declaration name for the 1105/// given Declarator. 1106DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1107 switch (D.getKind()) { 1108 case Declarator::DK_Abstract: 1109 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1110 return DeclarationName(); 1111 1112 case Declarator::DK_Normal: 1113 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1114 return DeclarationName(D.getIdentifier()); 1115 1116 case Declarator::DK_Constructor: { 1117 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1118 Ty = Context.getCanonicalType(Ty); 1119 return Context.DeclarationNames.getCXXConstructorName(Ty); 1120 } 1121 1122 case Declarator::DK_Destructor: { 1123 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1124 Ty = Context.getCanonicalType(Ty); 1125 return Context.DeclarationNames.getCXXDestructorName(Ty); 1126 } 1127 1128 case Declarator::DK_Conversion: { 1129 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1130 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1131 Ty = Context.getCanonicalType(Ty); 1132 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1133 } 1134 1135 case Declarator::DK_Operator: 1136 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1137 return Context.DeclarationNames.getCXXOperatorName( 1138 D.getOverloadedOperator()); 1139 } 1140 1141 assert(false && "Unknown name kind"); 1142 return DeclarationName(); 1143} 1144 1145/// isNearlyMatchingFunction - Determine whether the C++ functions 1146/// Declaration and Definition are "nearly" matching. This heuristic 1147/// is used to improve diagnostics in the case where an out-of-line 1148/// function definition doesn't match any declaration within 1149/// the class or namespace. 1150static bool isNearlyMatchingFunction(ASTContext &Context, 1151 FunctionDecl *Declaration, 1152 FunctionDecl *Definition) { 1153 if (Declaration->param_size() != Definition->param_size()) 1154 return false; 1155 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1156 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1157 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1158 1159 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1160 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1161 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1162 return false; 1163 } 1164 1165 return true; 1166} 1167 1168Sema::DeclTy * 1169Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1170 bool IsFunctionDefinition) { 1171 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1172 DeclarationName Name = GetNameForDeclarator(D); 1173 1174 // All of these full declarators require an identifier. If it doesn't have 1175 // one, the ParsedFreeStandingDeclSpec action should be used. 1176 if (!Name) { 1177 if (!D.getInvalidType()) // Reject this if we think it is valid. 1178 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1179 diag::err_declarator_need_ident) 1180 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1181 return 0; 1182 } 1183 1184 // The scope passed in may not be a decl scope. Zip up the scope tree until 1185 // we find one that is. 1186 while ((S->getFlags() & Scope::DeclScope) == 0 || 1187 (S->getFlags() & Scope::TemplateParamScope) != 0) 1188 S = S->getParent(); 1189 1190 DeclContext *DC; 1191 NamedDecl *PrevDecl; 1192 NamedDecl *New; 1193 bool InvalidDecl = false; 1194 1195 QualType R = GetTypeForDeclarator(D, S); 1196 if (R.isNull()) { 1197 InvalidDecl = true; 1198 R = Context.IntTy; 1199 } 1200 1201 // See if this is a redefinition of a variable in the same scope. 1202 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1203 LookupNameKind NameKind = LookupOrdinaryName; 1204 1205 // If the declaration we're planning to build will be a function 1206 // or object with linkage, then look for another declaration with 1207 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1208 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1209 /* Do nothing*/; 1210 else if (R->isFunctionType()) { 1211 if (CurContext->isFunctionOrMethod()) 1212 NameKind = LookupRedeclarationWithLinkage; 1213 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1214 NameKind = LookupRedeclarationWithLinkage; 1215 1216 DC = CurContext; 1217 PrevDecl = LookupName(S, Name, NameKind, true, 1218 D.getDeclSpec().getStorageClassSpec() != 1219 DeclSpec::SCS_static, 1220 D.getIdentifierLoc()); 1221 } else { // Something like "int foo::x;" 1222 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1223 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1224 1225 // C++ 7.3.1.2p2: 1226 // Members (including explicit specializations of templates) of a named 1227 // namespace can also be defined outside that namespace by explicit 1228 // qualification of the name being defined, provided that the entity being 1229 // defined was already declared in the namespace and the definition appears 1230 // after the point of declaration in a namespace that encloses the 1231 // declarations namespace. 1232 // 1233 // Note that we only check the context at this point. We don't yet 1234 // have enough information to make sure that PrevDecl is actually 1235 // the declaration we want to match. For example, given: 1236 // 1237 // class X { 1238 // void f(); 1239 // void f(float); 1240 // }; 1241 // 1242 // void X::f(int) { } // ill-formed 1243 // 1244 // In this case, PrevDecl will point to the overload set 1245 // containing the two f's declared in X, but neither of them 1246 // matches. 1247 1248 // First check whether we named the global scope. 1249 if (isa<TranslationUnitDecl>(DC)) { 1250 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1251 << Name << D.getCXXScopeSpec().getRange(); 1252 } else if (!CurContext->Encloses(DC)) { 1253 // The qualifying scope doesn't enclose the original declaration. 1254 // Emit diagnostic based on current scope. 1255 SourceLocation L = D.getIdentifierLoc(); 1256 SourceRange R = D.getCXXScopeSpec().getRange(); 1257 if (isa<FunctionDecl>(CurContext)) 1258 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1259 else 1260 Diag(L, diag::err_invalid_declarator_scope) 1261 << Name << cast<NamedDecl>(DC) << R; 1262 InvalidDecl = true; 1263 } 1264 } 1265 1266 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1267 // Maybe we will complain about the shadowed template parameter. 1268 InvalidDecl = InvalidDecl 1269 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1270 // Just pretend that we didn't see the previous declaration. 1271 PrevDecl = 0; 1272 } 1273 1274 // In C++, the previous declaration we find might be a tag type 1275 // (class or enum). In this case, the new declaration will hide the 1276 // tag type. Note that this does does not apply if we're declaring a 1277 // typedef (C++ [dcl.typedef]p4). 1278 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1279 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1280 PrevDecl = 0; 1281 1282 bool Redeclaration = false; 1283 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1284 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1285 InvalidDecl, Redeclaration); 1286 } else if (R->isFunctionType()) { 1287 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1288 IsFunctionDefinition, InvalidDecl, 1289 Redeclaration); 1290 } else { 1291 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1292 InvalidDecl, Redeclaration); 1293 } 1294 1295 if (New == 0) 1296 return 0; 1297 1298 // Set the lexical context. If the declarator has a C++ scope specifier, the 1299 // lexical context will be different from the semantic context. 1300 New->setLexicalDeclContext(CurContext); 1301 1302 // If this has an identifier and is not an invalid redeclaration, 1303 // add it to the scope stack. 1304 if (Name && !(Redeclaration && InvalidDecl)) 1305 PushOnScopeChains(New, S); 1306 // If any semantic error occurred, mark the decl as invalid. 1307 if (D.getInvalidType() || InvalidDecl) 1308 New->setInvalidDecl(); 1309 1310 return New; 1311} 1312 1313/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1314/// types into constant array types in certain situations which would otherwise 1315/// be errors (for GCC compatibility). 1316static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1317 ASTContext &Context, 1318 bool &SizeIsNegative) { 1319 // This method tries to turn a variable array into a constant 1320 // array even when the size isn't an ICE. This is necessary 1321 // for compatibility with code that depends on gcc's buggy 1322 // constant expression folding, like struct {char x[(int)(char*)2];} 1323 SizeIsNegative = false; 1324 1325 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1326 QualType Pointee = PTy->getPointeeType(); 1327 QualType FixedType = 1328 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1329 if (FixedType.isNull()) return FixedType; 1330 FixedType = Context.getPointerType(FixedType); 1331 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1332 return FixedType; 1333 } 1334 1335 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1336 if (!VLATy) return QualType(); 1337 1338 Expr::EvalResult EvalResult; 1339 if (!VLATy->getSizeExpr() || 1340 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 1341 return QualType(); 1342 1343 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 1344 llvm::APSInt &Res = EvalResult.Val.getInt(); 1345 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1346 return Context.getConstantArrayType(VLATy->getElementType(), 1347 Res, ArrayType::Normal, 0); 1348 1349 SizeIsNegative = true; 1350 return QualType(); 1351} 1352 1353NamedDecl* 1354Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1355 QualType R, Decl* LastDeclarator, 1356 Decl* PrevDecl, bool& InvalidDecl, 1357 bool &Redeclaration) { 1358 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1359 if (D.getCXXScopeSpec().isSet()) { 1360 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1361 << D.getCXXScopeSpec().getRange(); 1362 InvalidDecl = true; 1363 // Pretend we didn't see the scope specifier. 1364 DC = 0; 1365 } 1366 1367 // Check that there are no default arguments (C++ only). 1368 if (getLangOptions().CPlusPlus) 1369 CheckExtraCXXDefaultArguments(D); 1370 1371 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1372 if (!NewTD) return 0; 1373 1374 // Handle attributes prior to checking for duplicates in MergeVarDecl 1375 ProcessDeclAttributes(NewTD, D); 1376 // Merge the decl with the existing one if appropriate. If the decl is 1377 // in an outer scope, it isn't the same thing. 1378 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1379 Redeclaration = true; 1380 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1381 InvalidDecl = true; 1382 } 1383 1384 if (S->getFnParent() == 0) { 1385 QualType T = NewTD->getUnderlyingType(); 1386 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1387 // then it shall have block scope. 1388 if (T->isVariablyModifiedType()) { 1389 bool SizeIsNegative; 1390 QualType FixedTy = 1391 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1392 if (!FixedTy.isNull()) { 1393 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1394 NewTD->setUnderlyingType(FixedTy); 1395 } else { 1396 if (SizeIsNegative) 1397 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1398 else if (T->isVariableArrayType()) 1399 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1400 else 1401 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1402 InvalidDecl = true; 1403 } 1404 } 1405 } 1406 return NewTD; 1407} 1408 1409/// \brief Determines whether the given declaration is an out-of-scope 1410/// previous declaration. 1411/// 1412/// This routine should be invoked when name lookup has found a 1413/// previous declaration (PrevDecl) that is not in the scope where a 1414/// new declaration by the same name is being introduced. If the new 1415/// declaration occurs in a local scope, previous declarations with 1416/// linkage may still be considered previous declarations (C99 1417/// 6.2.2p4-5, C++ [basic.link]p6). 1418/// 1419/// \param PrevDecl the previous declaration found by name 1420/// lookup 1421/// 1422/// \param DC the context in which the new declaration is being 1423/// declared. 1424/// 1425/// \returns true if PrevDecl is an out-of-scope previous declaration 1426/// for a new delcaration with the same name. 1427static bool 1428isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1429 ASTContext &Context) { 1430 if (!PrevDecl) 1431 return 0; 1432 1433 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1434 // case we need to check each of the overloaded functions. 1435 if (!PrevDecl->hasLinkage()) 1436 return false; 1437 1438 if (Context.getLangOptions().CPlusPlus) { 1439 // C++ [basic.link]p6: 1440 // If there is a visible declaration of an entity with linkage 1441 // having the same name and type, ignoring entities declared 1442 // outside the innermost enclosing namespace scope, the block 1443 // scope declaration declares that same entity and receives the 1444 // linkage of the previous declaration. 1445 DeclContext *OuterContext = DC->getLookupContext(); 1446 if (!OuterContext->isFunctionOrMethod()) 1447 // This rule only applies to block-scope declarations. 1448 return false; 1449 else { 1450 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1451 if (PrevOuterContext->isRecord()) 1452 // We found a member function: ignore it. 1453 return false; 1454 else { 1455 // Find the innermost enclosing namespace for the new and 1456 // previous declarations. 1457 while (!OuterContext->isFileContext()) 1458 OuterContext = OuterContext->getParent(); 1459 while (!PrevOuterContext->isFileContext()) 1460 PrevOuterContext = PrevOuterContext->getParent(); 1461 1462 // The previous declaration is in a different namespace, so it 1463 // isn't the same function. 1464 if (OuterContext->getPrimaryContext() != 1465 PrevOuterContext->getPrimaryContext()) 1466 return false; 1467 } 1468 } 1469 } 1470 1471 return true; 1472} 1473 1474/// \brief Inject a locally-scoped declaration with external linkage 1475/// into the appropriate namespace scope. 1476/// 1477/// Given a declaration of an entity with linkage that occurs within a 1478/// local scope, this routine inject that declaration into top-level 1479/// scope so that it will be visible for later uses and declarations 1480/// of the same entity. 1481void Sema::InjectLocallyScopedExternalDeclaration(ValueDecl *VD) { 1482 // FIXME: We don't do this in C++ because, although we would like 1483 // to get the extra checking that this operation implies, 1484 // the declaration itself is not visible according to C++'s rules. 1485 assert(!getLangOptions().CPlusPlus && 1486 "Can't inject locally-scoped declarations in C++"); 1487 IdentifierResolver::iterator I = IdResolver.begin(VD->getDeclName()), 1488 IEnd = IdResolver.end(); 1489 NamedDecl *PrevDecl = 0; 1490 while (I != IEnd && !isa<TranslationUnitDecl>((*I)->getDeclContext())) { 1491 PrevDecl = *I; 1492 ++I; 1493 } 1494 1495 if (I == IEnd) { 1496 // No name with this identifier has been declared at translation 1497 // unit scope. Add this name into the appropriate scope. 1498 if (PrevDecl) 1499 IdResolver.AddShadowedDecl(VD, PrevDecl); 1500 else 1501 IdResolver.AddDecl(VD); 1502 TUScope->AddDecl(VD); 1503 return; 1504 } 1505 1506 if (isa<TagDecl>(*I)) { 1507 // The first thing we found was a tag declaration, so insert 1508 // this function so that it will be found before the tag 1509 // declaration. 1510 if (PrevDecl) 1511 IdResolver.AddShadowedDecl(VD, PrevDecl); 1512 else 1513 IdResolver.AddDecl(VD); 1514 TUScope->AddDecl(VD); 1515 return; 1516 } 1517 1518 if (VD->declarationReplaces(*I)) { 1519 // We found a previous declaration of the same entity. Replace 1520 // that declaration with this one. 1521 TUScope->RemoveDecl(*I); 1522 TUScope->AddDecl(VD); 1523 IdResolver.RemoveDecl(*I); 1524 if (PrevDecl) 1525 IdResolver.AddShadowedDecl(VD, PrevDecl); 1526 else 1527 IdResolver.AddDecl(VD); 1528 } 1529} 1530 1531NamedDecl* 1532Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1533 QualType R, Decl* LastDeclarator, 1534 NamedDecl* PrevDecl, bool& InvalidDecl, 1535 bool &Redeclaration) { 1536 DeclarationName Name = GetNameForDeclarator(D); 1537 1538 // Check that there are no default arguments (C++ only). 1539 if (getLangOptions().CPlusPlus) 1540 CheckExtraCXXDefaultArguments(D); 1541 1542 if (R.getTypePtr()->isObjCInterfaceType()) { 1543 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object); 1544 InvalidDecl = true; 1545 } 1546 1547 VarDecl *NewVD; 1548 VarDecl::StorageClass SC; 1549 switch (D.getDeclSpec().getStorageClassSpec()) { 1550 default: assert(0 && "Unknown storage class!"); 1551 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1552 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1553 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1554 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1555 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1556 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1557 case DeclSpec::SCS_mutable: 1558 // mutable can only appear on non-static class members, so it's always 1559 // an error here 1560 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1561 InvalidDecl = true; 1562 SC = VarDecl::None; 1563 break; 1564 } 1565 1566 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1567 if (!II) { 1568 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1569 << Name.getAsString(); 1570 return 0; 1571 } 1572 1573 if (DC->isRecord()) { 1574 // This is a static data member for a C++ class. 1575 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1576 D.getIdentifierLoc(), II, 1577 R); 1578 } else { 1579 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1580 if (S->getFnParent() == 0) { 1581 // C99 6.9p2: The storage-class specifiers auto and register shall not 1582 // appear in the declaration specifiers in an external declaration. 1583 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1584 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1585 InvalidDecl = true; 1586 } 1587 } 1588 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1589 II, R, SC, 1590 // FIXME: Move to DeclGroup... 1591 D.getDeclSpec().getSourceRange().getBegin()); 1592 NewVD->setThreadSpecified(ThreadSpecified); 1593 } 1594 NewVD->setNextDeclarator(LastDeclarator); 1595 1596 // Handle attributes prior to checking for duplicates in MergeVarDecl 1597 ProcessDeclAttributes(NewVD, D); 1598 1599 // Handle GNU asm-label extension (encoded as an attribute). 1600 if (Expr *E = (Expr*) D.getAsmLabel()) { 1601 // The parser guarantees this is a string. 1602 StringLiteral *SE = cast<StringLiteral>(E); 1603 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1604 SE->getByteLength()))); 1605 } 1606 1607 // Emit an error if an address space was applied to decl with local storage. 1608 // This includes arrays of objects with address space qualifiers, but not 1609 // automatic variables that point to other address spaces. 1610 // ISO/IEC TR 18037 S5.1.2 1611 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1612 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1613 InvalidDecl = true; 1614 } 1615 1616 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1617 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1618 } 1619 1620 // If name lookup finds a previous declaration that is not in the 1621 // same scope as the new declaration, this may still be an 1622 // acceptable redeclaration. 1623 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1624 !(NewVD->hasLinkage() && 1625 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1626 PrevDecl = 0; 1627 1628 // Merge the decl with the existing one if appropriate. 1629 if (PrevDecl) { 1630 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1631 // The user tried to define a non-static data member 1632 // out-of-line (C++ [dcl.meaning]p1). 1633 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1634 << D.getCXXScopeSpec().getRange(); 1635 NewVD->Destroy(Context); 1636 return 0; 1637 } 1638 1639 Redeclaration = true; 1640 if (MergeVarDecl(NewVD, PrevDecl)) 1641 InvalidDecl = true; 1642 1643 if (D.getCXXScopeSpec().isSet()) { 1644 // No previous declaration in the qualifying scope. 1645 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1646 << Name << D.getCXXScopeSpec().getRange(); 1647 InvalidDecl = true; 1648 } 1649 } 1650 1651 // If this is a locally-scoped extern variable in C, inject a 1652 // declaration into translation unit scope so that all external 1653 // declarations are visible. 1654 if (!getLangOptions().CPlusPlus && CurContext->isFunctionOrMethod() && 1655 NewVD->hasLinkage()) 1656 InjectLocallyScopedExternalDeclaration(NewVD); 1657 1658 return NewVD; 1659} 1660 1661NamedDecl* 1662Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1663 QualType R, Decl *LastDeclarator, 1664 NamedDecl* PrevDecl, bool IsFunctionDefinition, 1665 bool& InvalidDecl, bool &Redeclaration) { 1666 assert(R.getTypePtr()->isFunctionType()); 1667 1668 DeclarationName Name = GetNameForDeclarator(D); 1669 FunctionDecl::StorageClass SC = FunctionDecl::None; 1670 switch (D.getDeclSpec().getStorageClassSpec()) { 1671 default: assert(0 && "Unknown storage class!"); 1672 case DeclSpec::SCS_auto: 1673 case DeclSpec::SCS_register: 1674 case DeclSpec::SCS_mutable: 1675 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1676 diag::err_typecheck_sclass_func); 1677 InvalidDecl = true; 1678 break; 1679 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1680 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1681 case DeclSpec::SCS_static: { 1682 if (DC->getLookupContext()->isFunctionOrMethod()) { 1683 // C99 6.7.1p5: 1684 // The declaration of an identifier for a function that has 1685 // block scope shall have no explicit storage-class specifier 1686 // other than extern 1687 // See also (C++ [dcl.stc]p4). 1688 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1689 diag::err_static_block_func); 1690 SC = FunctionDecl::None; 1691 } else 1692 SC = FunctionDecl::Static; 1693 break; 1694 } 1695 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1696 } 1697 1698 bool isInline = D.getDeclSpec().isInlineSpecified(); 1699 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1700 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1701 1702 FunctionDecl *NewFD; 1703 if (D.getKind() == Declarator::DK_Constructor) { 1704 // This is a C++ constructor declaration. 1705 assert(DC->isRecord() && 1706 "Constructors can only be declared in a member context"); 1707 1708 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1709 1710 // Create the new declaration 1711 NewFD = CXXConstructorDecl::Create(Context, 1712 cast<CXXRecordDecl>(DC), 1713 D.getIdentifierLoc(), Name, R, 1714 isExplicit, isInline, 1715 /*isImplicitlyDeclared=*/false); 1716 1717 if (InvalidDecl) 1718 NewFD->setInvalidDecl(); 1719 } else if (D.getKind() == Declarator::DK_Destructor) { 1720 // This is a C++ destructor declaration. 1721 if (DC->isRecord()) { 1722 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1723 1724 NewFD = CXXDestructorDecl::Create(Context, 1725 cast<CXXRecordDecl>(DC), 1726 D.getIdentifierLoc(), Name, R, 1727 isInline, 1728 /*isImplicitlyDeclared=*/false); 1729 1730 if (InvalidDecl) 1731 NewFD->setInvalidDecl(); 1732 } else { 1733 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1734 1735 // Create a FunctionDecl to satisfy the function definition parsing 1736 // code path. 1737 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1738 Name, R, SC, isInline, 1739 // FIXME: Move to DeclGroup... 1740 D.getDeclSpec().getSourceRange().getBegin()); 1741 InvalidDecl = true; 1742 NewFD->setInvalidDecl(); 1743 } 1744 } else if (D.getKind() == Declarator::DK_Conversion) { 1745 if (!DC->isRecord()) { 1746 Diag(D.getIdentifierLoc(), 1747 diag::err_conv_function_not_member); 1748 return 0; 1749 } else { 1750 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1751 1752 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1753 D.getIdentifierLoc(), Name, R, 1754 isInline, isExplicit); 1755 1756 if (InvalidDecl) 1757 NewFD->setInvalidDecl(); 1758 } 1759 } else if (DC->isRecord()) { 1760 // This is a C++ method declaration. 1761 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1762 D.getIdentifierLoc(), Name, R, 1763 (SC == FunctionDecl::Static), isInline); 1764 } else { 1765 NewFD = FunctionDecl::Create(Context, DC, 1766 D.getIdentifierLoc(), 1767 Name, R, SC, isInline, 1768 // FIXME: Move to DeclGroup... 1769 D.getDeclSpec().getSourceRange().getBegin()); 1770 } 1771 NewFD->setNextDeclarator(LastDeclarator); 1772 1773 // Set the lexical context. If the declarator has a C++ 1774 // scope specifier, the lexical context will be different 1775 // from the semantic context. 1776 NewFD->setLexicalDeclContext(CurContext); 1777 1778 // Handle GNU asm-label extension (encoded as an attribute). 1779 if (Expr *E = (Expr*) D.getAsmLabel()) { 1780 // The parser guarantees this is a string. 1781 StringLiteral *SE = cast<StringLiteral>(E); 1782 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1783 SE->getByteLength()))); 1784 } 1785 1786 // Copy the parameter declarations from the declarator D to 1787 // the function declaration NewFD, if they are available. 1788 if (D.getNumTypeObjects() > 0) { 1789 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1790 1791 // Create Decl objects for each parameter, adding them to the 1792 // FunctionDecl. 1793 llvm::SmallVector<ParmVarDecl*, 16> Params; 1794 1795 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1796 // function that takes no arguments, not a function that takes a 1797 // single void argument. 1798 // We let through "const void" here because Sema::GetTypeForDeclarator 1799 // already checks for that case. 1800 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1801 FTI.ArgInfo[0].Param && 1802 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1803 // empty arg list, don't push any params. 1804 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1805 1806 // In C++, the empty parameter-type-list must be spelled "void"; a 1807 // typedef of void is not permitted. 1808 if (getLangOptions().CPlusPlus && 1809 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1810 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1811 } 1812 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1813 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1814 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1815 } 1816 1817 NewFD->setParams(Context, &Params[0], Params.size()); 1818 } else if (R->getAsTypedefType()) { 1819 // When we're declaring a function with a typedef, as in the 1820 // following example, we'll need to synthesize (unnamed) 1821 // parameters for use in the declaration. 1822 // 1823 // @code 1824 // typedef void fn(int); 1825 // fn f; 1826 // @endcode 1827 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1828 if (!FT) { 1829 // This is a typedef of a function with no prototype, so we 1830 // don't need to do anything. 1831 } else if ((FT->getNumArgs() == 0) || 1832 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1833 FT->getArgType(0)->isVoidType())) { 1834 // This is a zero-argument function. We don't need to do anything. 1835 } else { 1836 // Synthesize a parameter for each argument type. 1837 llvm::SmallVector<ParmVarDecl*, 16> Params; 1838 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1839 ArgType != FT->arg_type_end(); ++ArgType) { 1840 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1841 SourceLocation(), 0, 1842 *ArgType, VarDecl::None, 1843 0); 1844 Param->setImplicit(); 1845 Params.push_back(Param); 1846 } 1847 1848 NewFD->setParams(Context, &Params[0], Params.size()); 1849 } 1850 } 1851 1852 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1853 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1854 else if (isa<CXXDestructorDecl>(NewFD)) { 1855 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1856 Record->setUserDeclaredDestructor(true); 1857 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1858 // user-defined destructor. 1859 Record->setPOD(false); 1860 } else if (CXXConversionDecl *Conversion = 1861 dyn_cast<CXXConversionDecl>(NewFD)) 1862 ActOnConversionDeclarator(Conversion); 1863 1864 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1865 if (NewFD->isOverloadedOperator() && 1866 CheckOverloadedOperatorDeclaration(NewFD)) 1867 NewFD->setInvalidDecl(); 1868 1869 // If name lookup finds a previous declaration that is not in the 1870 // same scope as the new declaration, this may still be an 1871 // acceptable redeclaration. 1872 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1873 !(NewFD->hasLinkage() && 1874 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1875 PrevDecl = 0; 1876 1877 // Merge or overload the declaration with an existing declaration of 1878 // the same name, if appropriate. 1879 bool OverloadableAttrRequired = false; 1880 if (PrevDecl) { 1881 // Determine whether NewFD is an overload of PrevDecl or 1882 // a declaration that requires merging. If it's an overload, 1883 // there's no more work to do here; we'll just add the new 1884 // function to the scope. 1885 OverloadedFunctionDecl::function_iterator MatchedDecl; 1886 1887 if (!getLangOptions().CPlusPlus && 1888 AllowOverloadingOfFunction(PrevDecl, Context)) { 1889 OverloadableAttrRequired = true; 1890 1891 // Functions marked "overloadable" must have a prototype (that 1892 // we can't get through declaration merging). 1893 if (!R->getAsFunctionTypeProto()) { 1894 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 1895 << NewFD; 1896 InvalidDecl = true; 1897 Redeclaration = true; 1898 1899 // Turn this into a variadic function with no parameters. 1900 R = Context.getFunctionType(R->getAsFunctionType()->getResultType(), 1901 0, 0, true, 0); 1902 NewFD->setType(R); 1903 } 1904 } 1905 1906 if (PrevDecl && 1907 (!AllowOverloadingOfFunction(PrevDecl, Context) || 1908 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 1909 Redeclaration = true; 1910 Decl *OldDecl = PrevDecl; 1911 1912 // If PrevDecl was an overloaded function, extract the 1913 // FunctionDecl that matched. 1914 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1915 OldDecl = *MatchedDecl; 1916 1917 // NewFD and PrevDecl represent declarations that need to be 1918 // merged. 1919 if (MergeFunctionDecl(NewFD, OldDecl)) 1920 InvalidDecl = true; 1921 1922 if (!InvalidDecl) { 1923 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1924 1925 // An out-of-line member function declaration must also be a 1926 // definition (C++ [dcl.meaning]p1). 1927 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1928 !InvalidDecl) { 1929 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1930 << D.getCXXScopeSpec().getRange(); 1931 NewFD->setInvalidDecl(); 1932 } 1933 } 1934 } 1935 } 1936 1937 if (D.getCXXScopeSpec().isSet() && 1938 (!PrevDecl || !Redeclaration)) { 1939 // The user tried to provide an out-of-line definition for a 1940 // function that is a member of a class or namespace, but there 1941 // was no such member function declared (C++ [class.mfct]p2, 1942 // C++ [namespace.memdef]p2). For example: 1943 // 1944 // class X { 1945 // void f() const; 1946 // }; 1947 // 1948 // void X::f() { } // ill-formed 1949 // 1950 // Complain about this problem, and attempt to suggest close 1951 // matches (e.g., those that differ only in cv-qualifiers and 1952 // whether the parameter types are references). 1953 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1954 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 1955 InvalidDecl = true; 1956 1957 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1958 true); 1959 assert(!Prev.isAmbiguous() && 1960 "Cannot have an ambiguity in previous-declaration lookup"); 1961 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1962 Func != FuncEnd; ++Func) { 1963 if (isa<FunctionDecl>(*Func) && 1964 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 1965 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1966 } 1967 1968 PrevDecl = 0; 1969 } 1970 1971 // Handle attributes. We need to have merged decls when handling attributes 1972 // (for example to check for conflicts, etc). 1973 ProcessDeclAttributes(NewFD, D); 1974 AddKnownFunctionAttributes(NewFD); 1975 1976 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 1977 // If a function name is overloadable in C, then every function 1978 // with that name must be marked "overloadable". 1979 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 1980 << Redeclaration << NewFD; 1981 if (PrevDecl) 1982 Diag(PrevDecl->getLocation(), 1983 diag::note_attribute_overloadable_prev_overload); 1984 NewFD->addAttr(new OverloadableAttr); 1985 } 1986 1987 if (getLangOptions().CPlusPlus) { 1988 // In C++, check default arguments now that we have merged decls. Unless 1989 // the lexical context is the class, because in this case this is done 1990 // during delayed parsing anyway. 1991 if (!CurContext->isRecord()) 1992 CheckCXXDefaultArguments(NewFD); 1993 1994 // An out-of-line member function declaration must also be a 1995 // definition (C++ [dcl.meaning]p1). 1996 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1997 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1998 << D.getCXXScopeSpec().getRange(); 1999 InvalidDecl = true; 2000 } 2001 } 2002 2003 // If this is a locally-scoped function in C, inject a declaration 2004 // into translation unit scope so that all external declarations are 2005 // visible. 2006 if (!getLangOptions().CPlusPlus && CurContext->isFunctionOrMethod()) 2007 InjectLocallyScopedExternalDeclaration(NewFD); 2008 2009 return NewFD; 2010} 2011 2012void Sema::InitializerElementNotConstant(const Expr *Init) { 2013 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2014 << Init->getSourceRange(); 2015} 2016 2017bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 2018 switch (Init->getStmtClass()) { 2019 default: 2020 InitializerElementNotConstant(Init); 2021 return true; 2022 case Expr::ParenExprClass: { 2023 const ParenExpr* PE = cast<ParenExpr>(Init); 2024 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 2025 } 2026 case Expr::CompoundLiteralExprClass: 2027 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 2028 case Expr::DeclRefExprClass: 2029 case Expr::QualifiedDeclRefExprClass: { 2030 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2031 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 2032 if (VD->hasGlobalStorage()) 2033 return false; 2034 InitializerElementNotConstant(Init); 2035 return true; 2036 } 2037 if (isa<FunctionDecl>(D)) 2038 return false; 2039 InitializerElementNotConstant(Init); 2040 return true; 2041 } 2042 case Expr::MemberExprClass: { 2043 const MemberExpr *M = cast<MemberExpr>(Init); 2044 if (M->isArrow()) 2045 return CheckAddressConstantExpression(M->getBase()); 2046 return CheckAddressConstantExpressionLValue(M->getBase()); 2047 } 2048 case Expr::ArraySubscriptExprClass: { 2049 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 2050 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 2051 return CheckAddressConstantExpression(ASE->getBase()) || 2052 CheckArithmeticConstantExpression(ASE->getIdx()); 2053 } 2054 case Expr::StringLiteralClass: 2055 case Expr::ObjCEncodeExprClass: 2056 case Expr::PredefinedExprClass: 2057 return false; 2058 case Expr::UnaryOperatorClass: { 2059 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2060 2061 // C99 6.6p9 2062 if (Exp->getOpcode() == UnaryOperator::Deref) 2063 return CheckAddressConstantExpression(Exp->getSubExpr()); 2064 2065 InitializerElementNotConstant(Init); 2066 return true; 2067 } 2068 } 2069} 2070 2071bool Sema::CheckAddressConstantExpression(const Expr* Init) { 2072 switch (Init->getStmtClass()) { 2073 default: 2074 InitializerElementNotConstant(Init); 2075 return true; 2076 case Expr::ParenExprClass: 2077 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 2078 case Expr::StringLiteralClass: 2079 case Expr::ObjCEncodeExprClass: 2080 case Expr::ObjCStringLiteralClass: 2081 return false; 2082 case Expr::CallExprClass: 2083 case Expr::CXXOperatorCallExprClass: 2084 // __builtin___CFStringMakeConstantString is a valid constant l-value. 2085 if (cast<CallExpr>(Init)->isBuiltinCall(Context) == 2086 Builtin::BI__builtin___CFStringMakeConstantString) 2087 return false; 2088 2089 InitializerElementNotConstant(Init); 2090 return true; 2091 2092 case Expr::UnaryOperatorClass: { 2093 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2094 2095 // C99 6.6p9 2096 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2097 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 2098 2099 if (Exp->getOpcode() == UnaryOperator::Extension) 2100 return CheckAddressConstantExpression(Exp->getSubExpr()); 2101 2102 InitializerElementNotConstant(Init); 2103 return true; 2104 } 2105 case Expr::BinaryOperatorClass: { 2106 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 2107 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2108 2109 Expr *PExp = Exp->getLHS(); 2110 Expr *IExp = Exp->getRHS(); 2111 if (IExp->getType()->isPointerType()) 2112 std::swap(PExp, IExp); 2113 2114 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 2115 return CheckAddressConstantExpression(PExp) || 2116 CheckArithmeticConstantExpression(IExp); 2117 } 2118 case Expr::ImplicitCastExprClass: 2119 case Expr::CStyleCastExprClass: { 2120 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2121 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 2122 // Check for implicit promotion 2123 if (SubExpr->getType()->isFunctionType() || 2124 SubExpr->getType()->isArrayType()) 2125 return CheckAddressConstantExpressionLValue(SubExpr); 2126 } 2127 2128 // Check for pointer->pointer cast 2129 if (SubExpr->getType()->isPointerType()) 2130 return CheckAddressConstantExpression(SubExpr); 2131 2132 if (SubExpr->getType()->isIntegralType()) { 2133 // Check for the special-case of a pointer->int->pointer cast; 2134 // this isn't standard, but some code requires it. See 2135 // PR2720 for an example. 2136 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 2137 if (SubCast->getSubExpr()->getType()->isPointerType()) { 2138 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 2139 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2140 if (IntWidth >= PointerWidth) { 2141 return CheckAddressConstantExpression(SubCast->getSubExpr()); 2142 } 2143 } 2144 } 2145 } 2146 if (SubExpr->getType()->isArithmeticType()) { 2147 return CheckArithmeticConstantExpression(SubExpr); 2148 } 2149 2150 InitializerElementNotConstant(Init); 2151 return true; 2152 } 2153 case Expr::ConditionalOperatorClass: { 2154 // FIXME: Should we pedwarn here? 2155 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2156 if (!Exp->getCond()->getType()->isArithmeticType()) { 2157 InitializerElementNotConstant(Init); 2158 return true; 2159 } 2160 if (CheckArithmeticConstantExpression(Exp->getCond())) 2161 return true; 2162 if (Exp->getLHS() && 2163 CheckAddressConstantExpression(Exp->getLHS())) 2164 return true; 2165 return CheckAddressConstantExpression(Exp->getRHS()); 2166 } 2167 case Expr::AddrLabelExprClass: 2168 return false; 2169 } 2170} 2171 2172static const Expr* FindExpressionBaseAddress(const Expr* E); 2173 2174static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 2175 switch (E->getStmtClass()) { 2176 default: 2177 return E; 2178 case Expr::ParenExprClass: { 2179 const ParenExpr* PE = cast<ParenExpr>(E); 2180 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 2181 } 2182 case Expr::MemberExprClass: { 2183 const MemberExpr *M = cast<MemberExpr>(E); 2184 if (M->isArrow()) 2185 return FindExpressionBaseAddress(M->getBase()); 2186 return FindExpressionBaseAddressLValue(M->getBase()); 2187 } 2188 case Expr::ArraySubscriptExprClass: { 2189 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 2190 return FindExpressionBaseAddress(ASE->getBase()); 2191 } 2192 case Expr::UnaryOperatorClass: { 2193 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2194 2195 if (Exp->getOpcode() == UnaryOperator::Deref) 2196 return FindExpressionBaseAddress(Exp->getSubExpr()); 2197 2198 return E; 2199 } 2200 } 2201} 2202 2203static const Expr* FindExpressionBaseAddress(const Expr* E) { 2204 switch (E->getStmtClass()) { 2205 default: 2206 return E; 2207 case Expr::ParenExprClass: { 2208 const ParenExpr* PE = cast<ParenExpr>(E); 2209 return FindExpressionBaseAddress(PE->getSubExpr()); 2210 } 2211 case Expr::UnaryOperatorClass: { 2212 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2213 2214 // C99 6.6p9 2215 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2216 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 2217 2218 if (Exp->getOpcode() == UnaryOperator::Extension) 2219 return FindExpressionBaseAddress(Exp->getSubExpr()); 2220 2221 return E; 2222 } 2223 case Expr::BinaryOperatorClass: { 2224 const BinaryOperator *Exp = cast<BinaryOperator>(E); 2225 2226 Expr *PExp = Exp->getLHS(); 2227 Expr *IExp = Exp->getRHS(); 2228 if (IExp->getType()->isPointerType()) 2229 std::swap(PExp, IExp); 2230 2231 return FindExpressionBaseAddress(PExp); 2232 } 2233 case Expr::ImplicitCastExprClass: { 2234 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2235 2236 // Check for implicit promotion 2237 if (SubExpr->getType()->isFunctionType() || 2238 SubExpr->getType()->isArrayType()) 2239 return FindExpressionBaseAddressLValue(SubExpr); 2240 2241 // Check for pointer->pointer cast 2242 if (SubExpr->getType()->isPointerType()) 2243 return FindExpressionBaseAddress(SubExpr); 2244 2245 // We assume that we have an arithmetic expression here; 2246 // if we don't, we'll figure it out later 2247 return 0; 2248 } 2249 case Expr::CStyleCastExprClass: { 2250 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2251 2252 // Check for pointer->pointer cast 2253 if (SubExpr->getType()->isPointerType()) 2254 return FindExpressionBaseAddress(SubExpr); 2255 2256 // We assume that we have an arithmetic expression here; 2257 // if we don't, we'll figure it out later 2258 return 0; 2259 } 2260 } 2261} 2262 2263bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2264 switch (Init->getStmtClass()) { 2265 default: 2266 InitializerElementNotConstant(Init); 2267 return true; 2268 case Expr::ParenExprClass: { 2269 const ParenExpr* PE = cast<ParenExpr>(Init); 2270 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2271 } 2272 case Expr::FloatingLiteralClass: 2273 case Expr::IntegerLiteralClass: 2274 case Expr::CharacterLiteralClass: 2275 case Expr::ImaginaryLiteralClass: 2276 case Expr::TypesCompatibleExprClass: 2277 case Expr::CXXBoolLiteralExprClass: 2278 return false; 2279 case Expr::CallExprClass: 2280 case Expr::CXXOperatorCallExprClass: { 2281 const CallExpr *CE = cast<CallExpr>(Init); 2282 2283 // Allow any constant foldable calls to builtins. 2284 if (CE->isBuiltinCall(Context) && CE->isEvaluatable(Context)) 2285 return false; 2286 2287 InitializerElementNotConstant(Init); 2288 return true; 2289 } 2290 case Expr::DeclRefExprClass: 2291 case Expr::QualifiedDeclRefExprClass: { 2292 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2293 if (isa<EnumConstantDecl>(D)) 2294 return false; 2295 InitializerElementNotConstant(Init); 2296 return true; 2297 } 2298 case Expr::CompoundLiteralExprClass: 2299 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2300 // but vectors are allowed to be magic. 2301 if (Init->getType()->isVectorType()) 2302 return false; 2303 InitializerElementNotConstant(Init); 2304 return true; 2305 case Expr::UnaryOperatorClass: { 2306 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2307 2308 switch (Exp->getOpcode()) { 2309 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2310 // See C99 6.6p3. 2311 default: 2312 InitializerElementNotConstant(Init); 2313 return true; 2314 case UnaryOperator::OffsetOf: 2315 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2316 return false; 2317 InitializerElementNotConstant(Init); 2318 return true; 2319 case UnaryOperator::Extension: 2320 case UnaryOperator::LNot: 2321 case UnaryOperator::Plus: 2322 case UnaryOperator::Minus: 2323 case UnaryOperator::Not: 2324 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2325 } 2326 } 2327 case Expr::SizeOfAlignOfExprClass: { 2328 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2329 // Special check for void types, which are allowed as an extension 2330 if (Exp->getTypeOfArgument()->isVoidType()) 2331 return false; 2332 // alignof always evaluates to a constant. 2333 // FIXME: is sizeof(int[3.0]) a constant expression? 2334 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2335 InitializerElementNotConstant(Init); 2336 return true; 2337 } 2338 return false; 2339 } 2340 case Expr::BinaryOperatorClass: { 2341 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2342 2343 if (Exp->getLHS()->getType()->isArithmeticType() && 2344 Exp->getRHS()->getType()->isArithmeticType()) { 2345 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2346 CheckArithmeticConstantExpression(Exp->getRHS()); 2347 } 2348 2349 if (Exp->getLHS()->getType()->isPointerType() && 2350 Exp->getRHS()->getType()->isPointerType()) { 2351 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2352 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2353 2354 // Only allow a null (constant integer) base; we could 2355 // allow some additional cases if necessary, but this 2356 // is sufficient to cover offsetof-like constructs. 2357 if (!LHSBase && !RHSBase) { 2358 return CheckAddressConstantExpression(Exp->getLHS()) || 2359 CheckAddressConstantExpression(Exp->getRHS()); 2360 } 2361 } 2362 2363 InitializerElementNotConstant(Init); 2364 return true; 2365 } 2366 case Expr::ImplicitCastExprClass: 2367 case Expr::CStyleCastExprClass: { 2368 const CastExpr *CE = cast<CastExpr>(Init); 2369 const Expr *SubExpr = CE->getSubExpr(); 2370 2371 if (SubExpr->getType()->isArithmeticType()) 2372 return CheckArithmeticConstantExpression(SubExpr); 2373 2374 if (SubExpr->getType()->isPointerType()) { 2375 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2376 if (Base) { 2377 // the cast is only valid if done to a wide enough type 2378 if (Context.getTypeSize(CE->getType()) >= 2379 Context.getTypeSize(SubExpr->getType())) 2380 return false; 2381 } else { 2382 // If the pointer has a null base, this is an offsetof-like construct 2383 return CheckAddressConstantExpression(SubExpr); 2384 } 2385 } 2386 2387 InitializerElementNotConstant(Init); 2388 return true; 2389 } 2390 case Expr::ConditionalOperatorClass: { 2391 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2392 2393 // If GNU extensions are disabled, we require all operands to be arithmetic 2394 // constant expressions. 2395 if (getLangOptions().NoExtensions) { 2396 return CheckArithmeticConstantExpression(Exp->getCond()) || 2397 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2398 CheckArithmeticConstantExpression(Exp->getRHS()); 2399 } 2400 2401 // Otherwise, we have to emulate some of the behavior of fold here. 2402 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2403 // because it can constant fold things away. To retain compatibility with 2404 // GCC code, we see if we can fold the condition to a constant (which we 2405 // should always be able to do in theory). If so, we only require the 2406 // specified arm of the conditional to be a constant. This is a horrible 2407 // hack, but is require by real world code that uses __builtin_constant_p. 2408 Expr::EvalResult EvalResult; 2409 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2410 EvalResult.HasSideEffects) { 2411 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2412 // won't be able to either. Use it to emit the diagnostic though. 2413 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2414 assert(Res && "Evaluate couldn't evaluate this constant?"); 2415 return Res; 2416 } 2417 2418 // Verify that the side following the condition is also a constant. 2419 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2420 if (EvalResult.Val.getInt() == 0) 2421 std::swap(TrueSide, FalseSide); 2422 2423 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2424 return true; 2425 2426 // Okay, the evaluated side evaluates to a constant, so we accept this. 2427 // Check to see if the other side is obviously not a constant. If so, 2428 // emit a warning that this is a GNU extension. 2429 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2430 Diag(Init->getExprLoc(), 2431 diag::ext_typecheck_expression_not_constant_but_accepted) 2432 << FalseSide->getSourceRange(); 2433 return false; 2434 } 2435 } 2436} 2437 2438bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2439 if (Init->isConstantInitializer(Context)) 2440 return false; 2441 InitializerElementNotConstant(Init); 2442 return true; 2443 2444 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2445 Init = DIE->getInit(); 2446 2447 Init = Init->IgnoreParens(); 2448 2449 if (Init->isEvaluatable(Context)) 2450 return false; 2451 2452 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2453 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2454 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2455 2456 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2457 return CheckForConstantInitializer(e->getInitializer(), DclT); 2458 2459 if (isa<ImplicitValueInitExpr>(Init)) { 2460 // FIXME: In C++, check for non-POD types. 2461 return false; 2462 } 2463 2464 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2465 unsigned numInits = Exp->getNumInits(); 2466 for (unsigned i = 0; i < numInits; i++) { 2467 // FIXME: Need to get the type of the declaration for C++, 2468 // because it could be a reference? 2469 2470 if (CheckForConstantInitializer(Exp->getInit(i), 2471 Exp->getInit(i)->getType())) 2472 return true; 2473 } 2474 return false; 2475 } 2476 2477 // FIXME: We can probably remove some of this code below, now that 2478 // Expr::Evaluate is doing the heavy lifting for scalars. 2479 2480 if (Init->isNullPointerConstant(Context)) 2481 return false; 2482 if (Init->getType()->isArithmeticType()) { 2483 QualType InitTy = Context.getCanonicalType(Init->getType()) 2484 .getUnqualifiedType(); 2485 if (InitTy == Context.BoolTy) { 2486 // Special handling for pointers implicitly cast to bool; 2487 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2488 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2489 Expr* SubE = ICE->getSubExpr(); 2490 if (SubE->getType()->isPointerType() || 2491 SubE->getType()->isArrayType() || 2492 SubE->getType()->isFunctionType()) { 2493 return CheckAddressConstantExpression(Init); 2494 } 2495 } 2496 } else if (InitTy->isIntegralType()) { 2497 Expr* SubE = 0; 2498 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2499 SubE = CE->getSubExpr(); 2500 // Special check for pointer cast to int; we allow as an extension 2501 // an address constant cast to an integer if the integer 2502 // is of an appropriate width (this sort of code is apparently used 2503 // in some places). 2504 // FIXME: Add pedwarn? 2505 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2506 if (SubE && (SubE->getType()->isPointerType() || 2507 SubE->getType()->isArrayType() || 2508 SubE->getType()->isFunctionType())) { 2509 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2510 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2511 if (IntWidth >= PointerWidth) 2512 return CheckAddressConstantExpression(Init); 2513 } 2514 } 2515 2516 return CheckArithmeticConstantExpression(Init); 2517 } 2518 2519 if (Init->getType()->isPointerType()) 2520 return CheckAddressConstantExpression(Init); 2521 2522 // An array type at the top level that isn't an init-list must 2523 // be a string literal 2524 if (Init->getType()->isArrayType()) 2525 return false; 2526 2527 if (Init->getType()->isFunctionType()) 2528 return false; 2529 2530 // Allow block exprs at top level. 2531 if (Init->getType()->isBlockPointerType()) 2532 return false; 2533 2534 // GCC cast to union extension 2535 // note: the validity of the cast expr is checked by CheckCastTypes() 2536 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2537 QualType T = C->getType(); 2538 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2539 } 2540 2541 InitializerElementNotConstant(Init); 2542 return true; 2543} 2544 2545void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2546 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2547} 2548 2549/// AddInitializerToDecl - Adds the initializer Init to the 2550/// declaration dcl. If DirectInit is true, this is C++ direct 2551/// initialization rather than copy initialization. 2552void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2553 Decl *RealDecl = static_cast<Decl *>(dcl); 2554 Expr *Init = static_cast<Expr *>(init.release()); 2555 assert(Init && "missing initializer"); 2556 2557 // If there is no declaration, there was an error parsing it. Just ignore 2558 // the initializer. 2559 if (RealDecl == 0) { 2560 Init->Destroy(Context); 2561 return; 2562 } 2563 2564 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2565 if (!VDecl) { 2566 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2567 RealDecl->setInvalidDecl(); 2568 return; 2569 } 2570 // Get the decls type and save a reference for later, since 2571 // CheckInitializerTypes may change it. 2572 QualType DclT = VDecl->getType(), SavT = DclT; 2573 if (VDecl->isBlockVarDecl()) { 2574 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2575 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2576 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2577 VDecl->setInvalidDecl(); 2578 } else if (!VDecl->isInvalidDecl()) { 2579 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2580 VDecl->getDeclName(), DirectInit)) 2581 VDecl->setInvalidDecl(); 2582 2583 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2584 // Don't check invalid declarations to avoid emitting useless diagnostics. 2585 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2586 if (SC == VarDecl::Static) // C99 6.7.8p4. 2587 CheckForConstantInitializer(Init, DclT); 2588 } 2589 } 2590 } else if (VDecl->isFileVarDecl()) { 2591 if (VDecl->getStorageClass() == VarDecl::Extern) 2592 Diag(VDecl->getLocation(), diag::warn_extern_init); 2593 if (!VDecl->isInvalidDecl()) 2594 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2595 VDecl->getDeclName(), DirectInit)) 2596 VDecl->setInvalidDecl(); 2597 2598 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2599 // Don't check invalid declarations to avoid emitting useless diagnostics. 2600 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2601 // C99 6.7.8p4. All file scoped initializers need to be constant. 2602 CheckForConstantInitializer(Init, DclT); 2603 } 2604 } 2605 // If the type changed, it means we had an incomplete type that was 2606 // completed by the initializer. For example: 2607 // int ary[] = { 1, 3, 5 }; 2608 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2609 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2610 VDecl->setType(DclT); 2611 Init->setType(DclT); 2612 } 2613 2614 // Attach the initializer to the decl. 2615 VDecl->setInit(Init); 2616 return; 2617} 2618 2619void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2620 Decl *RealDecl = static_cast<Decl *>(dcl); 2621 2622 // If there is no declaration, there was an error parsing it. Just ignore it. 2623 if (RealDecl == 0) 2624 return; 2625 2626 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2627 QualType Type = Var->getType(); 2628 // C++ [dcl.init.ref]p3: 2629 // The initializer can be omitted for a reference only in a 2630 // parameter declaration (8.3.5), in the declaration of a 2631 // function return type, in the declaration of a class member 2632 // within its class declaration (9.2), and where the extern 2633 // specifier is explicitly used. 2634 if (Type->isReferenceType() && 2635 Var->getStorageClass() != VarDecl::Extern && 2636 Var->getStorageClass() != VarDecl::PrivateExtern) { 2637 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2638 << Var->getDeclName() 2639 << SourceRange(Var->getLocation(), Var->getLocation()); 2640 Var->setInvalidDecl(); 2641 return; 2642 } 2643 2644 // C++ [dcl.init]p9: 2645 // 2646 // If no initializer is specified for an object, and the object 2647 // is of (possibly cv-qualified) non-POD class type (or array 2648 // thereof), the object shall be default-initialized; if the 2649 // object is of const-qualified type, the underlying class type 2650 // shall have a user-declared default constructor. 2651 if (getLangOptions().CPlusPlus) { 2652 QualType InitType = Type; 2653 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2654 InitType = Array->getElementType(); 2655 if (Var->getStorageClass() != VarDecl::Extern && 2656 Var->getStorageClass() != VarDecl::PrivateExtern && 2657 InitType->isRecordType()) { 2658 const CXXConstructorDecl *Constructor 2659 = PerformInitializationByConstructor(InitType, 0, 0, 2660 Var->getLocation(), 2661 SourceRange(Var->getLocation(), 2662 Var->getLocation()), 2663 Var->getDeclName(), 2664 IK_Default); 2665 if (!Constructor) 2666 Var->setInvalidDecl(); 2667 } 2668 } 2669 2670#if 0 2671 // FIXME: Temporarily disabled because we are not properly parsing 2672 // linkage specifications on declarations, e.g., 2673 // 2674 // extern "C" const CGPoint CGPointerZero; 2675 // 2676 // C++ [dcl.init]p9: 2677 // 2678 // If no initializer is specified for an object, and the 2679 // object is of (possibly cv-qualified) non-POD class type (or 2680 // array thereof), the object shall be default-initialized; if 2681 // the object is of const-qualified type, the underlying class 2682 // type shall have a user-declared default 2683 // constructor. Otherwise, if no initializer is specified for 2684 // an object, the object and its subobjects, if any, have an 2685 // indeterminate initial value; if the object or any of its 2686 // subobjects are of const-qualified type, the program is 2687 // ill-formed. 2688 // 2689 // This isn't technically an error in C, so we don't diagnose it. 2690 // 2691 // FIXME: Actually perform the POD/user-defined default 2692 // constructor check. 2693 if (getLangOptions().CPlusPlus && 2694 Context.getCanonicalType(Type).isConstQualified() && 2695 Var->getStorageClass() != VarDecl::Extern) 2696 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2697 << Var->getName() 2698 << SourceRange(Var->getLocation(), Var->getLocation()); 2699#endif 2700 } 2701} 2702 2703/// The declarators are chained together backwards, reverse the list. 2704Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2705 // Often we have single declarators, handle them quickly. 2706 Decl *Group = static_cast<Decl*>(group); 2707 if (Group == 0) 2708 return 0; 2709 2710 Decl *NewGroup = 0; 2711 if (Group->getNextDeclarator() == 0) 2712 NewGroup = Group; 2713 else { // reverse the list. 2714 while (Group) { 2715 Decl *Next = Group->getNextDeclarator(); 2716 Group->setNextDeclarator(NewGroup); 2717 NewGroup = Group; 2718 Group = Next; 2719 } 2720 } 2721 // Perform semantic analysis that depends on having fully processed both 2722 // the declarator and initializer. 2723 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2724 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2725 if (!IDecl) 2726 continue; 2727 QualType T = IDecl->getType(); 2728 2729 if (T->isVariableArrayType()) { 2730 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2731 2732 // FIXME: This won't give the correct result for 2733 // int a[10][n]; 2734 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2735 if (IDecl->isFileVarDecl()) { 2736 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2737 SizeRange; 2738 2739 IDecl->setInvalidDecl(); 2740 } else { 2741 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2742 // static storage duration, it shall not have a variable length array. 2743 if (IDecl->getStorageClass() == VarDecl::Static) { 2744 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2745 << SizeRange; 2746 IDecl->setInvalidDecl(); 2747 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2748 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2749 << SizeRange; 2750 IDecl->setInvalidDecl(); 2751 } 2752 } 2753 } else if (T->isVariablyModifiedType()) { 2754 if (IDecl->isFileVarDecl()) { 2755 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2756 IDecl->setInvalidDecl(); 2757 } else { 2758 if (IDecl->getStorageClass() == VarDecl::Extern) { 2759 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2760 IDecl->setInvalidDecl(); 2761 } 2762 } 2763 } 2764 2765 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2766 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2767 if (IDecl->isBlockVarDecl() && 2768 IDecl->getStorageClass() != VarDecl::Extern) { 2769 if (!IDecl->isInvalidDecl() && 2770 DiagnoseIncompleteType(IDecl->getLocation(), T, 2771 diag::err_typecheck_decl_incomplete_type)) 2772 IDecl->setInvalidDecl(); 2773 } 2774 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2775 // object that has file scope without an initializer, and without a 2776 // storage-class specifier or with the storage-class specifier "static", 2777 // constitutes a tentative definition. Note: A tentative definition with 2778 // external linkage is valid (C99 6.2.2p5). 2779 if (isTentativeDefinition(IDecl)) { 2780 if (T->isIncompleteArrayType()) { 2781 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2782 // array to be completed. Don't issue a diagnostic. 2783 } else if (!IDecl->isInvalidDecl() && 2784 DiagnoseIncompleteType(IDecl->getLocation(), T, 2785 diag::err_typecheck_decl_incomplete_type)) 2786 // C99 6.9.2p3: If the declaration of an identifier for an object is 2787 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2788 // declared type shall not be an incomplete type. 2789 IDecl->setInvalidDecl(); 2790 } 2791 if (IDecl->isFileVarDecl()) 2792 CheckForFileScopedRedefinitions(S, IDecl); 2793 } 2794 return NewGroup; 2795} 2796 2797/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2798/// to introduce parameters into function prototype scope. 2799Sema::DeclTy * 2800Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2801 const DeclSpec &DS = D.getDeclSpec(); 2802 2803 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2804 VarDecl::StorageClass StorageClass = VarDecl::None; 2805 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2806 StorageClass = VarDecl::Register; 2807 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2808 Diag(DS.getStorageClassSpecLoc(), 2809 diag::err_invalid_storage_class_in_func_decl); 2810 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2811 } 2812 if (DS.isThreadSpecified()) { 2813 Diag(DS.getThreadSpecLoc(), 2814 diag::err_invalid_storage_class_in_func_decl); 2815 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2816 } 2817 2818 // Check that there are no default arguments inside the type of this 2819 // parameter (C++ only). 2820 if (getLangOptions().CPlusPlus) 2821 CheckExtraCXXDefaultArguments(D); 2822 2823 // In this context, we *do not* check D.getInvalidType(). If the declarator 2824 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2825 // though it will not reflect the user specified type. 2826 QualType parmDeclType = GetTypeForDeclarator(D, S); 2827 2828 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2829 2830 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2831 // Can this happen for params? We already checked that they don't conflict 2832 // among each other. Here they can only shadow globals, which is ok. 2833 IdentifierInfo *II = D.getIdentifier(); 2834 if (II) { 2835 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2836 if (PrevDecl->isTemplateParameter()) { 2837 // Maybe we will complain about the shadowed template parameter. 2838 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2839 // Just pretend that we didn't see the previous declaration. 2840 PrevDecl = 0; 2841 } else if (S->isDeclScope(PrevDecl)) { 2842 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2843 2844 // Recover by removing the name 2845 II = 0; 2846 D.SetIdentifier(0, D.getIdentifierLoc()); 2847 } 2848 } 2849 } 2850 2851 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2852 // Doing the promotion here has a win and a loss. The win is the type for 2853 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2854 // code generator). The loss is the orginal type isn't preserved. For example: 2855 // 2856 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2857 // int blockvardecl[5]; 2858 // sizeof(parmvardecl); // size == 4 2859 // sizeof(blockvardecl); // size == 20 2860 // } 2861 // 2862 // For expressions, all implicit conversions are captured using the 2863 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2864 // 2865 // FIXME: If a source translation tool needs to see the original type, then 2866 // we need to consider storing both types (in ParmVarDecl)... 2867 // 2868 if (parmDeclType->isArrayType()) { 2869 // int x[restrict 4] -> int *restrict 2870 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2871 } else if (parmDeclType->isFunctionType()) 2872 parmDeclType = Context.getPointerType(parmDeclType); 2873 2874 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2875 D.getIdentifierLoc(), II, 2876 parmDeclType, StorageClass, 2877 0); 2878 2879 if (D.getInvalidType()) 2880 New->setInvalidDecl(); 2881 2882 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2883 if (D.getCXXScopeSpec().isSet()) { 2884 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2885 << D.getCXXScopeSpec().getRange(); 2886 New->setInvalidDecl(); 2887 } 2888 // Parameter declarators cannot be interface types. All ObjC objects are 2889 // passed by reference. 2890 if (parmDeclType->isObjCInterfaceType()) { 2891 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2892 << "passed"; 2893 New->setInvalidDecl(); 2894 } 2895 2896 // Add the parameter declaration into this scope. 2897 S->AddDecl(New); 2898 if (II) 2899 IdResolver.AddDecl(New); 2900 2901 ProcessDeclAttributes(New, D); 2902 return New; 2903 2904} 2905 2906void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2907 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2908 "Not a function declarator!"); 2909 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2910 2911 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2912 // for a K&R function. 2913 if (!FTI.hasPrototype) { 2914 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2915 if (FTI.ArgInfo[i].Param == 0) { 2916 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2917 << FTI.ArgInfo[i].Ident; 2918 // Implicitly declare the argument as type 'int' for lack of a better 2919 // type. 2920 DeclSpec DS; 2921 const char* PrevSpec; // unused 2922 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2923 PrevSpec); 2924 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2925 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2926 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2927 } 2928 } 2929 } 2930} 2931 2932Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2933 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2934 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2935 "Not a function declarator!"); 2936 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2937 2938 if (FTI.hasPrototype) { 2939 // FIXME: Diagnose arguments without names in C. 2940 } 2941 2942 Scope *ParentScope = FnBodyScope->getParent(); 2943 2944 return ActOnStartOfFunctionDef(FnBodyScope, 2945 ActOnDeclarator(ParentScope, D, 0, 2946 /*IsFunctionDefinition=*/true)); 2947} 2948 2949Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2950 Decl *decl = static_cast<Decl*>(D); 2951 FunctionDecl *FD = cast<FunctionDecl>(decl); 2952 2953 // See if this is a redefinition. 2954 const FunctionDecl *Definition; 2955 if (FD->getBody(Definition)) { 2956 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2957 Diag(Definition->getLocation(), diag::note_previous_definition); 2958 } 2959 2960 // Builtin functions cannot be defined. 2961 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2962 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2963 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2964 FD->setInvalidDecl(); 2965 } 2966 } 2967 2968 PushDeclContext(FnBodyScope, FD); 2969 2970 // Check the validity of our function parameters 2971 CheckParmsForFunctionDef(FD); 2972 2973 // Introduce our parameters into the function scope 2974 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2975 ParmVarDecl *Param = FD->getParamDecl(p); 2976 Param->setOwningFunction(FD); 2977 2978 // If this has an identifier, add it to the scope stack. 2979 if (Param->getIdentifier()) 2980 PushOnScopeChains(Param, FnBodyScope); 2981 } 2982 2983 // Checking attributes of current function definition 2984 // dllimport attribute. 2985 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2986 // dllimport attribute cannot be applied to definition. 2987 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2988 Diag(FD->getLocation(), 2989 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2990 << "dllimport"; 2991 FD->setInvalidDecl(); 2992 return FD; 2993 } else { 2994 // If a symbol previously declared dllimport is later defined, the 2995 // attribute is ignored in subsequent references, and a warning is 2996 // emitted. 2997 Diag(FD->getLocation(), 2998 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2999 << FD->getNameAsCString() << "dllimport"; 3000 } 3001 } 3002 return FD; 3003} 3004 3005Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 3006 Decl *dcl = static_cast<Decl *>(D); 3007 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 3008 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3009 FD->setBody(Body); 3010 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3011 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3012 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3013 MD->setBody((Stmt*)Body); 3014 } else { 3015 Body->Destroy(Context); 3016 return 0; 3017 } 3018 PopDeclContext(); 3019 // Verify and clean out per-function state. 3020 3021 // Check goto/label use. 3022 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3023 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 3024 // Verify that we have no forward references left. If so, there was a goto 3025 // or address of a label taken, but no definition of it. Label fwd 3026 // definitions are indicated with a null substmt. 3027 if (I->second->getSubStmt() == 0) { 3028 LabelStmt *L = I->second; 3029 // Emit error. 3030 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3031 3032 // At this point, we have gotos that use the bogus label. Stitch it into 3033 // the function body so that they aren't leaked and that the AST is well 3034 // formed. 3035 if (Body) { 3036#if 0 3037 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 3038 // and the AST is malformed anyway. We should just blow away 'L'. 3039 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3040 cast<CompoundStmt>(Body)->push_back(L); 3041#else 3042 L->Destroy(Context); 3043#endif 3044 } else { 3045 // The whole function wasn't parsed correctly, just delete this. 3046 L->Destroy(Context); 3047 } 3048 } 3049 } 3050 LabelMap.clear(); 3051 3052 return D; 3053} 3054 3055/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3056/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3057NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3058 IdentifierInfo &II, Scope *S) { 3059 // Extension in C99. Legal in C90, but warn about it. 3060 if (getLangOptions().C99) 3061 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3062 else 3063 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3064 3065 // FIXME: handle stuff like: 3066 // void foo() { extern float X(); } 3067 // void bar() { X(); } <-- implicit decl for X in another scope. 3068 3069 // Set a Declarator for the implicit definition: int foo(); 3070 const char *Dummy; 3071 DeclSpec DS; 3072 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3073 Error = Error; // Silence warning. 3074 assert(!Error && "Error setting up implicit decl!"); 3075 Declarator D(DS, Declarator::BlockContext); 3076 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3077 0, 0, 0, Loc, D), 3078 SourceLocation()); 3079 D.SetIdentifier(&II, Loc); 3080 3081 // Insert this function into translation-unit scope. 3082 3083 DeclContext *PrevDC = CurContext; 3084 CurContext = Context.getTranslationUnitDecl(); 3085 3086 FunctionDecl *FD = 3087 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 3088 FD->setImplicit(); 3089 3090 CurContext = PrevDC; 3091 3092 AddKnownFunctionAttributes(FD); 3093 3094 return FD; 3095} 3096 3097/// \brief Adds any function attributes that we know a priori based on 3098/// the declaration of this function. 3099/// 3100/// These attributes can apply both to implicitly-declared builtins 3101/// (like __builtin___printf_chk) or to library-declared functions 3102/// like NSLog or printf. 3103void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3104 if (FD->isInvalidDecl()) 3105 return; 3106 3107 // If this is a built-in function, map its builtin attributes to 3108 // actual attributes. 3109 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3110 // Handle printf-formatting attributes. 3111 unsigned FormatIdx; 3112 bool HasVAListArg; 3113 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3114 if (!FD->getAttr<FormatAttr>()) 3115 FD->addAttr(new FormatAttr("printf", FormatIdx + 1, FormatIdx + 2)); 3116 } 3117 3118 // Mark const if we don't care about errno and that is the only 3119 // thing preventing the function from being const. This allows 3120 // IRgen to use LLVM intrinsics for such functions. 3121 if (!getLangOptions().MathErrno && 3122 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3123 if (!FD->getAttr<ConstAttr>()) 3124 FD->addAttr(new ConstAttr()); 3125 } 3126 } 3127 3128 IdentifierInfo *Name = FD->getIdentifier(); 3129 if (!Name) 3130 return; 3131 if ((!getLangOptions().CPlusPlus && 3132 FD->getDeclContext()->isTranslationUnit()) || 3133 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3134 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3135 LinkageSpecDecl::lang_c)) { 3136 // Okay: this could be a libc/libm/Objective-C function we know 3137 // about. 3138 } else 3139 return; 3140 3141 unsigned KnownID; 3142 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3143 if (KnownFunctionIDs[KnownID] == Name) 3144 break; 3145 3146 switch (KnownID) { 3147 case id_NSLog: 3148 case id_NSLogv: 3149 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3150 // FIXME: We known better than our headers. 3151 const_cast<FormatAttr *>(Format)->setType("printf"); 3152 } else 3153 FD->addAttr(new FormatAttr("printf", 1, 2)); 3154 break; 3155 3156 case id_asprintf: 3157 case id_vasprintf: 3158 if (!FD->getAttr<FormatAttr>()) 3159 FD->addAttr(new FormatAttr("printf", 2, 3)); 3160 break; 3161 3162 default: 3163 // Unknown function or known function without any attributes to 3164 // add. Do nothing. 3165 break; 3166 } 3167} 3168 3169TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 3170 Decl *LastDeclarator) { 3171 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3172 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3173 3174 // Scope manipulation handled by caller. 3175 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3176 D.getIdentifierLoc(), 3177 D.getIdentifier(), 3178 T); 3179 NewTD->setNextDeclarator(LastDeclarator); 3180 if (D.getInvalidType()) 3181 NewTD->setInvalidDecl(); 3182 return NewTD; 3183} 3184 3185/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3186/// former case, Name will be non-null. In the later case, Name will be null. 3187/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3188/// reference/declaration/definition of a tag. 3189Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3190 SourceLocation KWLoc, const CXXScopeSpec &SS, 3191 IdentifierInfo *Name, SourceLocation NameLoc, 3192 AttributeList *Attr) { 3193 // If this is not a definition, it must have a name. 3194 assert((Name != 0 || TK == TK_Definition) && 3195 "Nameless record must be a definition!"); 3196 3197 TagDecl::TagKind Kind; 3198 switch (TagSpec) { 3199 default: assert(0 && "Unknown tag type!"); 3200 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3201 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3202 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3203 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3204 } 3205 3206 DeclContext *SearchDC = CurContext; 3207 DeclContext *DC = CurContext; 3208 NamedDecl *PrevDecl = 0; 3209 3210 bool Invalid = false; 3211 3212 if (Name && SS.isNotEmpty()) { 3213 // We have a nested-name tag ('struct foo::bar'). 3214 3215 // Check for invalid 'foo::'. 3216 if (SS.isInvalid()) { 3217 Name = 0; 3218 goto CreateNewDecl; 3219 } 3220 3221 DC = static_cast<DeclContext*>(SS.getScopeRep()); 3222 SearchDC = DC; 3223 // Look-up name inside 'foo::'. 3224 PrevDecl = dyn_cast_or_null<TagDecl>( 3225 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3226 3227 // A tag 'foo::bar' must already exist. 3228 if (PrevDecl == 0) { 3229 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3230 Name = 0; 3231 goto CreateNewDecl; 3232 } 3233 } else if (Name) { 3234 // If this is a named struct, check to see if there was a previous forward 3235 // declaration or definition. 3236 // FIXME: We're looking into outer scopes here, even when we 3237 // shouldn't be. Doing so can result in ambiguities that we 3238 // shouldn't be diagnosing. 3239 LookupResult R = LookupName(S, Name, LookupTagName, 3240 /*RedeclarationOnly=*/(TK != TK_Reference)); 3241 if (R.isAmbiguous()) { 3242 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3243 // FIXME: This is not best way to recover from case like: 3244 // 3245 // struct S s; 3246 // 3247 // causes needless err_ovl_no_viable_function_in_init latter. 3248 Name = 0; 3249 PrevDecl = 0; 3250 Invalid = true; 3251 } 3252 else 3253 PrevDecl = R; 3254 3255 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3256 // FIXME: This makes sure that we ignore the contexts associated 3257 // with C structs, unions, and enums when looking for a matching 3258 // tag declaration or definition. See the similar lookup tweak 3259 // in Sema::LookupName; is there a better way to deal with this? 3260 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3261 SearchDC = SearchDC->getParent(); 3262 } 3263 } 3264 3265 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3266 // Maybe we will complain about the shadowed template parameter. 3267 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3268 // Just pretend that we didn't see the previous declaration. 3269 PrevDecl = 0; 3270 } 3271 3272 if (PrevDecl) { 3273 // Check whether the previous declaration is usable. 3274 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3275 3276 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3277 // If this is a use of a previous tag, or if the tag is already declared 3278 // in the same scope (so that the definition/declaration completes or 3279 // rementions the tag), reuse the decl. 3280 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3281 // Make sure that this wasn't declared as an enum and now used as a 3282 // struct or something similar. 3283 if (PrevTagDecl->getTagKind() != Kind) { 3284 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3285 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3286 // Recover by making this an anonymous redefinition. 3287 Name = 0; 3288 PrevDecl = 0; 3289 Invalid = true; 3290 } else { 3291 // If this is a use, just return the declaration we found. 3292 3293 // FIXME: In the future, return a variant or some other clue 3294 // for the consumer of this Decl to know it doesn't own it. 3295 // For our current ASTs this shouldn't be a problem, but will 3296 // need to be changed with DeclGroups. 3297 if (TK == TK_Reference) 3298 return PrevDecl; 3299 3300 // Diagnose attempts to redefine a tag. 3301 if (TK == TK_Definition) { 3302 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3303 Diag(NameLoc, diag::err_redefinition) << Name; 3304 Diag(Def->getLocation(), diag::note_previous_definition); 3305 // If this is a redefinition, recover by making this 3306 // struct be anonymous, which will make any later 3307 // references get the previous definition. 3308 Name = 0; 3309 PrevDecl = 0; 3310 Invalid = true; 3311 } else { 3312 // If the type is currently being defined, complain 3313 // about a nested redefinition. 3314 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3315 if (Tag->isBeingDefined()) { 3316 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3317 Diag(PrevTagDecl->getLocation(), 3318 diag::note_previous_definition); 3319 Name = 0; 3320 PrevDecl = 0; 3321 Invalid = true; 3322 } 3323 } 3324 3325 // Okay, this is definition of a previously declared or referenced 3326 // tag PrevDecl. We're going to create a new Decl for it. 3327 } 3328 } 3329 // If we get here we have (another) forward declaration or we 3330 // have a definition. Just create a new decl. 3331 } else { 3332 // If we get here, this is a definition of a new tag type in a nested 3333 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3334 // new decl/type. We set PrevDecl to NULL so that the entities 3335 // have distinct types. 3336 PrevDecl = 0; 3337 } 3338 // If we get here, we're going to create a new Decl. If PrevDecl 3339 // is non-NULL, it's a definition of the tag declared by 3340 // PrevDecl. If it's NULL, we have a new definition. 3341 } else { 3342 // PrevDecl is a namespace, template, or anything else 3343 // that lives in the IDNS_Tag identifier namespace. 3344 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3345 // The tag name clashes with a namespace name, issue an error and 3346 // recover by making this tag be anonymous. 3347 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3348 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3349 Name = 0; 3350 PrevDecl = 0; 3351 Invalid = true; 3352 } else { 3353 // The existing declaration isn't relevant to us; we're in a 3354 // new scope, so clear out the previous declaration. 3355 PrevDecl = 0; 3356 } 3357 } 3358 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3359 (Kind != TagDecl::TK_enum)) { 3360 // C++ [basic.scope.pdecl]p5: 3361 // -- for an elaborated-type-specifier of the form 3362 // 3363 // class-key identifier 3364 // 3365 // if the elaborated-type-specifier is used in the 3366 // decl-specifier-seq or parameter-declaration-clause of a 3367 // function defined in namespace scope, the identifier is 3368 // declared as a class-name in the namespace that contains 3369 // the declaration; otherwise, except as a friend 3370 // declaration, the identifier is declared in the smallest 3371 // non-class, non-function-prototype scope that contains the 3372 // declaration. 3373 // 3374 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3375 // C structs and unions. 3376 3377 // Find the context where we'll be declaring the tag. 3378 // FIXME: We would like to maintain the current DeclContext as the 3379 // lexical context, 3380 while (SearchDC->isRecord()) 3381 SearchDC = SearchDC->getParent(); 3382 3383 // Find the scope where we'll be declaring the tag. 3384 while (S->isClassScope() || 3385 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3386 ((S->getFlags() & Scope::DeclScope) == 0) || 3387 (S->getEntity() && 3388 ((DeclContext *)S->getEntity())->isTransparentContext())) 3389 S = S->getParent(); 3390 } 3391 3392CreateNewDecl: 3393 3394 // If there is an identifier, use the location of the identifier as the 3395 // location of the decl, otherwise use the location of the struct/union 3396 // keyword. 3397 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3398 3399 // Otherwise, create a new declaration. If there is a previous 3400 // declaration of the same entity, the two will be linked via 3401 // PrevDecl. 3402 TagDecl *New; 3403 3404 if (Kind == TagDecl::TK_enum) { 3405 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3406 // enum X { A, B, C } D; D should chain to X. 3407 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3408 cast_or_null<EnumDecl>(PrevDecl)); 3409 // If this is an undefined enum, warn. 3410 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3411 } else { 3412 // struct/union/class 3413 3414 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3415 // struct X { int A; } D; D should chain to X. 3416 if (getLangOptions().CPlusPlus) 3417 // FIXME: Look for a way to use RecordDecl for simple structs. 3418 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3419 cast_or_null<CXXRecordDecl>(PrevDecl)); 3420 else 3421 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3422 cast_or_null<RecordDecl>(PrevDecl)); 3423 } 3424 3425 if (Kind != TagDecl::TK_enum) { 3426 // Handle #pragma pack: if the #pragma pack stack has non-default 3427 // alignment, make up a packed attribute for this decl. These 3428 // attributes are checked when the ASTContext lays out the 3429 // structure. 3430 // 3431 // It is important for implementing the correct semantics that this 3432 // happen here (in act on tag decl). The #pragma pack stack is 3433 // maintained as a result of parser callbacks which can occur at 3434 // many points during the parsing of a struct declaration (because 3435 // the #pragma tokens are effectively skipped over during the 3436 // parsing of the struct). 3437 if (unsigned Alignment = getPragmaPackAlignment()) 3438 New->addAttr(new PackedAttr(Alignment * 8)); 3439 } 3440 3441 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3442 // C++ [dcl.typedef]p3: 3443 // [...] Similarly, in a given scope, a class or enumeration 3444 // shall not be declared with the same name as a typedef-name 3445 // that is declared in that scope and refers to a type other 3446 // than the class or enumeration itself. 3447 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3448 TypedefDecl *PrevTypedef = 0; 3449 if (Lookup.getKind() == LookupResult::Found) 3450 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3451 3452 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3453 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3454 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3455 Diag(Loc, diag::err_tag_definition_of_typedef) 3456 << Context.getTypeDeclType(New) 3457 << PrevTypedef->getUnderlyingType(); 3458 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3459 Invalid = true; 3460 } 3461 } 3462 3463 if (Invalid) 3464 New->setInvalidDecl(); 3465 3466 if (Attr) 3467 ProcessDeclAttributeList(New, Attr); 3468 3469 // If we're declaring or defining a tag in function prototype scope 3470 // in C, note that this type can only be used within the function. 3471 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3472 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3473 3474 // Set the lexical context. If the tag has a C++ scope specifier, the 3475 // lexical context will be different from the semantic context. 3476 New->setLexicalDeclContext(CurContext); 3477 3478 if (TK == TK_Definition) 3479 New->startDefinition(); 3480 3481 // If this has an identifier, add it to the scope stack. 3482 if (Name) { 3483 S = getNonFieldDeclScope(S); 3484 PushOnScopeChains(New, S); 3485 } else { 3486 CurContext->addDecl(New); 3487 } 3488 3489 return New; 3490} 3491 3492void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3493 AdjustDeclIfTemplate(TagD); 3494 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3495 3496 // Enter the tag context. 3497 PushDeclContext(S, Tag); 3498 3499 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3500 FieldCollector->StartClass(); 3501 3502 if (Record->getIdentifier()) { 3503 // C++ [class]p2: 3504 // [...] The class-name is also inserted into the scope of the 3505 // class itself; this is known as the injected-class-name. For 3506 // purposes of access checking, the injected-class-name is treated 3507 // as if it were a public member name. 3508 RecordDecl *InjectedClassName 3509 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3510 CurContext, Record->getLocation(), 3511 Record->getIdentifier(), Record); 3512 InjectedClassName->setImplicit(); 3513 PushOnScopeChains(InjectedClassName, S); 3514 } 3515 } 3516} 3517 3518void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3519 AdjustDeclIfTemplate(TagD); 3520 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3521 3522 if (isa<CXXRecordDecl>(Tag)) 3523 FieldCollector->FinishClass(); 3524 3525 // Exit this scope of this tag's definition. 3526 PopDeclContext(); 3527 3528 // Notify the consumer that we've defined a tag. 3529 Consumer.HandleTagDeclDefinition(Tag); 3530} 3531 3532bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3533 QualType FieldTy, const Expr *BitWidth) { 3534 // FIXME: 6.7.2.1p4 - verify the field type. 3535 3536 llvm::APSInt Value; 3537 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3538 return true; 3539 3540 // Zero-width bitfield is ok for anonymous field. 3541 if (Value == 0 && FieldName) 3542 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3543 3544 if (Value.isNegative()) 3545 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3546 3547 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3548 // FIXME: We won't need the 0 size once we check that the field type is valid. 3549 if (TypeSize && Value.getZExtValue() > TypeSize) 3550 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3551 << FieldName << (unsigned)TypeSize; 3552 3553 return false; 3554} 3555 3556/// ActOnField - Each field of a struct/union/class is passed into this in order 3557/// to create a FieldDecl object for it. 3558Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3559 SourceLocation DeclStart, 3560 Declarator &D, ExprTy *BitfieldWidth) { 3561 IdentifierInfo *II = D.getIdentifier(); 3562 Expr *BitWidth = (Expr*)BitfieldWidth; 3563 SourceLocation Loc = DeclStart; 3564 RecordDecl *Record = (RecordDecl *)TagD; 3565 if (II) Loc = D.getIdentifierLoc(); 3566 3567 // FIXME: Unnamed fields can be handled in various different ways, for 3568 // example, unnamed unions inject all members into the struct namespace! 3569 3570 QualType T = GetTypeForDeclarator(D, S); 3571 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3572 bool InvalidDecl = false; 3573 3574 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3575 // than a variably modified type. 3576 if (T->isVariablyModifiedType()) { 3577 bool SizeIsNegative; 3578 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3579 SizeIsNegative); 3580 if (!FixedTy.isNull()) { 3581 Diag(Loc, diag::warn_illegal_constant_array_size); 3582 T = FixedTy; 3583 } else { 3584 if (SizeIsNegative) 3585 Diag(Loc, diag::err_typecheck_negative_array_size); 3586 else 3587 Diag(Loc, diag::err_typecheck_field_variable_size); 3588 T = Context.IntTy; 3589 InvalidDecl = true; 3590 } 3591 } 3592 3593 if (BitWidth) { 3594 if (VerifyBitField(Loc, II, T, BitWidth)) 3595 InvalidDecl = true; 3596 } else { 3597 // Not a bitfield. 3598 3599 // validate II. 3600 3601 } 3602 3603 FieldDecl *NewFD = FieldDecl::Create(Context, Record, 3604 Loc, II, T, BitWidth, 3605 D.getDeclSpec().getStorageClassSpec() == 3606 DeclSpec::SCS_mutable); 3607 3608 if (II) { 3609 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3610 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3611 && !isa<TagDecl>(PrevDecl)) { 3612 Diag(Loc, diag::err_duplicate_member) << II; 3613 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3614 NewFD->setInvalidDecl(); 3615 Record->setInvalidDecl(); 3616 } 3617 } 3618 3619 if (getLangOptions().CPlusPlus) { 3620 CheckExtraCXXDefaultArguments(D); 3621 if (!T->isPODType()) 3622 cast<CXXRecordDecl>(Record)->setPOD(false); 3623 } 3624 3625 ProcessDeclAttributes(NewFD, D); 3626 if (T.isObjCGCWeak()) 3627 Diag(Loc, diag::warn_attribute_weak_on_field); 3628 3629 if (D.getInvalidType() || InvalidDecl) 3630 NewFD->setInvalidDecl(); 3631 3632 if (II) { 3633 PushOnScopeChains(NewFD, S); 3634 } else 3635 Record->addDecl(NewFD); 3636 3637 return NewFD; 3638} 3639 3640/// TranslateIvarVisibility - Translate visibility from a token ID to an 3641/// AST enum value. 3642static ObjCIvarDecl::AccessControl 3643TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3644 switch (ivarVisibility) { 3645 default: assert(0 && "Unknown visitibility kind"); 3646 case tok::objc_private: return ObjCIvarDecl::Private; 3647 case tok::objc_public: return ObjCIvarDecl::Public; 3648 case tok::objc_protected: return ObjCIvarDecl::Protected; 3649 case tok::objc_package: return ObjCIvarDecl::Package; 3650 } 3651} 3652 3653/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3654/// in order to create an IvarDecl object for it. 3655Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3656 SourceLocation DeclStart, 3657 Declarator &D, ExprTy *BitfieldWidth, 3658 tok::ObjCKeywordKind Visibility) { 3659 3660 IdentifierInfo *II = D.getIdentifier(); 3661 Expr *BitWidth = (Expr*)BitfieldWidth; 3662 SourceLocation Loc = DeclStart; 3663 if (II) Loc = D.getIdentifierLoc(); 3664 3665 // FIXME: Unnamed fields can be handled in various different ways, for 3666 // example, unnamed unions inject all members into the struct namespace! 3667 3668 QualType T = GetTypeForDeclarator(D, S); 3669 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3670 bool InvalidDecl = false; 3671 3672 if (BitWidth) { 3673 // 6.7.2.1p3, 6.7.2.1p4 3674 if (VerifyBitField(Loc, II, T, BitWidth)) 3675 InvalidDecl = true; 3676 } else { 3677 // Not a bitfield. 3678 3679 // validate II. 3680 3681 } 3682 3683 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3684 // than a variably modified type. 3685 if (T->isVariablyModifiedType()) { 3686 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3687 InvalidDecl = true; 3688 } 3689 3690 // Get the visibility (access control) for this ivar. 3691 ObjCIvarDecl::AccessControl ac = 3692 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3693 : ObjCIvarDecl::None; 3694 3695 // Construct the decl. 3696 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3697 (Expr *)BitfieldWidth); 3698 3699 if (II) { 3700 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3701 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3702 && !isa<TagDecl>(PrevDecl)) { 3703 Diag(Loc, diag::err_duplicate_member) << II; 3704 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3705 NewID->setInvalidDecl(); 3706 } 3707 } 3708 3709 // Process attributes attached to the ivar. 3710 ProcessDeclAttributes(NewID, D); 3711 3712 if (D.getInvalidType() || InvalidDecl) 3713 NewID->setInvalidDecl(); 3714 3715 if (II) { 3716 // FIXME: When interfaces are DeclContexts, we'll need to add 3717 // these to the interface. 3718 S->AddDecl(NewID); 3719 IdResolver.AddDecl(NewID); 3720 } 3721 3722 return NewID; 3723} 3724 3725void Sema::ActOnFields(Scope* S, 3726 SourceLocation RecLoc, DeclTy *RecDecl, 3727 DeclTy **Fields, unsigned NumFields, 3728 SourceLocation LBrac, SourceLocation RBrac, 3729 AttributeList *Attr) { 3730 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3731 assert(EnclosingDecl && "missing record or interface decl"); 3732 3733 // If the decl this is being inserted into is invalid, then it may be a 3734 // redeclaration or some other bogus case. Don't try to add fields to it. 3735 if (EnclosingDecl->isInvalidDecl()) { 3736 // FIXME: Deallocate fields? 3737 return; 3738 } 3739 3740 3741 // Verify that all the fields are okay. 3742 unsigned NumNamedMembers = 0; 3743 llvm::SmallVector<FieldDecl*, 32> RecFields; 3744 3745 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3746 for (unsigned i = 0; i != NumFields; ++i) { 3747 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3748 assert(FD && "missing field decl"); 3749 3750 // Get the type for the field. 3751 Type *FDTy = FD->getType().getTypePtr(); 3752 3753 if (!FD->isAnonymousStructOrUnion()) { 3754 // Remember all fields written by the user. 3755 RecFields.push_back(FD); 3756 } 3757 3758 // C99 6.7.2.1p2 - A field may not be a function type. 3759 if (FDTy->isFunctionType()) { 3760 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3761 << FD->getDeclName(); 3762 FD->setInvalidDecl(); 3763 EnclosingDecl->setInvalidDecl(); 3764 continue; 3765 } 3766 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3767 if (FDTy->isIncompleteType()) { 3768 if (!Record) { // Incomplete ivar type is always an error. 3769 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3770 diag::err_field_incomplete); 3771 FD->setInvalidDecl(); 3772 EnclosingDecl->setInvalidDecl(); 3773 continue; 3774 } 3775 if (i != NumFields-1 || // ... that the last member ... 3776 !Record->isStruct() || // ... of a structure ... 3777 !FDTy->isArrayType()) { //... may have incomplete array type. 3778 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3779 diag::err_field_incomplete); 3780 FD->setInvalidDecl(); 3781 EnclosingDecl->setInvalidDecl(); 3782 continue; 3783 } 3784 if (NumNamedMembers < 1) { //... must have more than named member ... 3785 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3786 << FD->getDeclName(); 3787 FD->setInvalidDecl(); 3788 EnclosingDecl->setInvalidDecl(); 3789 continue; 3790 } 3791 // Okay, we have a legal flexible array member at the end of the struct. 3792 if (Record) 3793 Record->setHasFlexibleArrayMember(true); 3794 } 3795 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3796 /// field of another structure or the element of an array. 3797 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3798 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3799 // If this is a member of a union, then entire union becomes "flexible". 3800 if (Record && Record->isUnion()) { 3801 Record->setHasFlexibleArrayMember(true); 3802 } else { 3803 // If this is a struct/class and this is not the last element, reject 3804 // it. Note that GCC supports variable sized arrays in the middle of 3805 // structures. 3806 if (i != NumFields-1) { 3807 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3808 << FD->getDeclName(); 3809 FD->setInvalidDecl(); 3810 EnclosingDecl->setInvalidDecl(); 3811 continue; 3812 } 3813 // We support flexible arrays at the end of structs in other structs 3814 // as an extension. 3815 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3816 << FD->getDeclName(); 3817 if (Record) 3818 Record->setHasFlexibleArrayMember(true); 3819 } 3820 } 3821 } 3822 /// A field cannot be an Objective-c object 3823 if (FDTy->isObjCInterfaceType()) { 3824 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3825 FD->setInvalidDecl(); 3826 EnclosingDecl->setInvalidDecl(); 3827 continue; 3828 } 3829 // Keep track of the number of named members. 3830 if (FD->getIdentifier()) 3831 ++NumNamedMembers; 3832 } 3833 3834 // Okay, we successfully defined 'Record'. 3835 if (Record) { 3836 Record->completeDefinition(Context); 3837 } else { 3838 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3839 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3840 ID->setIVarList(ClsFields, RecFields.size(), Context); 3841 ID->setLocEnd(RBrac); 3842 3843 // Must enforce the rule that ivars in the base classes may not be 3844 // duplicates. 3845 if (ID->getSuperClass()) { 3846 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3847 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3848 ObjCIvarDecl* Ivar = (*IVI); 3849 IdentifierInfo *II = Ivar->getIdentifier(); 3850 ObjCIvarDecl* prevIvar = ID->getSuperClass()->lookupInstanceVariable(II); 3851 if (prevIvar) { 3852 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3853 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3854 } 3855 } 3856 } 3857 } else if (ObjCImplementationDecl *IMPDecl = 3858 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3859 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3860 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3861 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3862 } 3863 } 3864 3865 if (Attr) 3866 ProcessDeclAttributeList(Record, Attr); 3867} 3868 3869Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3870 DeclTy *lastEnumConst, 3871 SourceLocation IdLoc, IdentifierInfo *Id, 3872 SourceLocation EqualLoc, ExprTy *val) { 3873 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3874 EnumConstantDecl *LastEnumConst = 3875 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3876 Expr *Val = static_cast<Expr*>(val); 3877 3878 // The scope passed in may not be a decl scope. Zip up the scope tree until 3879 // we find one that is. 3880 S = getNonFieldDeclScope(S); 3881 3882 // Verify that there isn't already something declared with this name in this 3883 // scope. 3884 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3885 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3886 // Maybe we will complain about the shadowed template parameter. 3887 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3888 // Just pretend that we didn't see the previous declaration. 3889 PrevDecl = 0; 3890 } 3891 3892 if (PrevDecl) { 3893 // When in C++, we may get a TagDecl with the same name; in this case the 3894 // enum constant will 'hide' the tag. 3895 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3896 "Received TagDecl when not in C++!"); 3897 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3898 if (isa<EnumConstantDecl>(PrevDecl)) 3899 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3900 else 3901 Diag(IdLoc, diag::err_redefinition) << Id; 3902 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3903 Val->Destroy(Context); 3904 return 0; 3905 } 3906 } 3907 3908 llvm::APSInt EnumVal(32); 3909 QualType EltTy; 3910 if (Val) { 3911 // Make sure to promote the operand type to int. 3912 UsualUnaryConversions(Val); 3913 3914 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3915 SourceLocation ExpLoc; 3916 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3917 Val->Destroy(Context); 3918 Val = 0; // Just forget about it. 3919 } else { 3920 EltTy = Val->getType(); 3921 } 3922 } 3923 3924 if (!Val) { 3925 if (LastEnumConst) { 3926 // Assign the last value + 1. 3927 EnumVal = LastEnumConst->getInitVal(); 3928 ++EnumVal; 3929 3930 // Check for overflow on increment. 3931 if (EnumVal < LastEnumConst->getInitVal()) 3932 Diag(IdLoc, diag::warn_enum_value_overflow); 3933 3934 EltTy = LastEnumConst->getType(); 3935 } else { 3936 // First value, set to zero. 3937 EltTy = Context.IntTy; 3938 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3939 } 3940 } 3941 3942 EnumConstantDecl *New = 3943 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3944 Val, EnumVal); 3945 3946 // Register this decl in the current scope stack. 3947 PushOnScopeChains(New, S); 3948 3949 return New; 3950} 3951 3952// FIXME: For consistency with ActOnFields(), we should have the parser 3953// pass in the source location for the left/right braces. 3954void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3955 DeclTy **Elements, unsigned NumElements) { 3956 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3957 QualType EnumType = Context.getTypeDeclType(Enum); 3958 3959 // TODO: If the result value doesn't fit in an int, it must be a long or long 3960 // long value. ISO C does not support this, but GCC does as an extension, 3961 // emit a warning. 3962 unsigned IntWidth = Context.Target.getIntWidth(); 3963 3964 // Verify that all the values are okay, compute the size of the values, and 3965 // reverse the list. 3966 unsigned NumNegativeBits = 0; 3967 unsigned NumPositiveBits = 0; 3968 3969 // Keep track of whether all elements have type int. 3970 bool AllElementsInt = true; 3971 3972 for (unsigned i = 0; i != NumElements; ++i) { 3973 EnumConstantDecl *ECD = 3974 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3975 if (!ECD) continue; // Already issued a diagnostic. 3976 3977 // If the enum value doesn't fit in an int, emit an extension warning. 3978 const llvm::APSInt &InitVal = ECD->getInitVal(); 3979 assert(InitVal.getBitWidth() >= IntWidth && 3980 "Should have promoted value to int"); 3981 if (InitVal.getBitWidth() > IntWidth) { 3982 llvm::APSInt V(InitVal); 3983 V.trunc(IntWidth); 3984 V.extend(InitVal.getBitWidth()); 3985 if (V != InitVal) 3986 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3987 << InitVal.toString(10); 3988 } 3989 3990 // Keep track of the size of positive and negative values. 3991 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3992 NumPositiveBits = std::max(NumPositiveBits, 3993 (unsigned)InitVal.getActiveBits()); 3994 else 3995 NumNegativeBits = std::max(NumNegativeBits, 3996 (unsigned)InitVal.getMinSignedBits()); 3997 3998 // Keep track of whether every enum element has type int (very commmon). 3999 if (AllElementsInt) 4000 AllElementsInt = ECD->getType() == Context.IntTy; 4001 } 4002 4003 // Figure out the type that should be used for this enum. 4004 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4005 QualType BestType; 4006 unsigned BestWidth; 4007 4008 if (NumNegativeBits) { 4009 // If there is a negative value, figure out the smallest integer type (of 4010 // int/long/longlong) that fits. 4011 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4012 BestType = Context.IntTy; 4013 BestWidth = IntWidth; 4014 } else { 4015 BestWidth = Context.Target.getLongWidth(); 4016 4017 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4018 BestType = Context.LongTy; 4019 else { 4020 BestWidth = Context.Target.getLongLongWidth(); 4021 4022 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4023 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4024 BestType = Context.LongLongTy; 4025 } 4026 } 4027 } else { 4028 // If there is no negative value, figure out which of uint, ulong, ulonglong 4029 // fits. 4030 if (NumPositiveBits <= IntWidth) { 4031 BestType = Context.UnsignedIntTy; 4032 BestWidth = IntWidth; 4033 } else if (NumPositiveBits <= 4034 (BestWidth = Context.Target.getLongWidth())) { 4035 BestType = Context.UnsignedLongTy; 4036 } else { 4037 BestWidth = Context.Target.getLongLongWidth(); 4038 assert(NumPositiveBits <= BestWidth && 4039 "How could an initializer get larger than ULL?"); 4040 BestType = Context.UnsignedLongLongTy; 4041 } 4042 } 4043 4044 // Loop over all of the enumerator constants, changing their types to match 4045 // the type of the enum if needed. 4046 for (unsigned i = 0; i != NumElements; ++i) { 4047 EnumConstantDecl *ECD = 4048 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 4049 if (!ECD) continue; // Already issued a diagnostic. 4050 4051 // Standard C says the enumerators have int type, but we allow, as an 4052 // extension, the enumerators to be larger than int size. If each 4053 // enumerator value fits in an int, type it as an int, otherwise type it the 4054 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4055 // that X has type 'int', not 'unsigned'. 4056 if (ECD->getType() == Context.IntTy) { 4057 // Make sure the init value is signed. 4058 llvm::APSInt IV = ECD->getInitVal(); 4059 IV.setIsSigned(true); 4060 ECD->setInitVal(IV); 4061 4062 if (getLangOptions().CPlusPlus) 4063 // C++ [dcl.enum]p4: Following the closing brace of an 4064 // enum-specifier, each enumerator has the type of its 4065 // enumeration. 4066 ECD->setType(EnumType); 4067 continue; // Already int type. 4068 } 4069 4070 // Determine whether the value fits into an int. 4071 llvm::APSInt InitVal = ECD->getInitVal(); 4072 bool FitsInInt; 4073 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4074 FitsInInt = InitVal.getActiveBits() < IntWidth; 4075 else 4076 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4077 4078 // If it fits into an integer type, force it. Otherwise force it to match 4079 // the enum decl type. 4080 QualType NewTy; 4081 unsigned NewWidth; 4082 bool NewSign; 4083 if (FitsInInt) { 4084 NewTy = Context.IntTy; 4085 NewWidth = IntWidth; 4086 NewSign = true; 4087 } else if (ECD->getType() == BestType) { 4088 // Already the right type! 4089 if (getLangOptions().CPlusPlus) 4090 // C++ [dcl.enum]p4: Following the closing brace of an 4091 // enum-specifier, each enumerator has the type of its 4092 // enumeration. 4093 ECD->setType(EnumType); 4094 continue; 4095 } else { 4096 NewTy = BestType; 4097 NewWidth = BestWidth; 4098 NewSign = BestType->isSignedIntegerType(); 4099 } 4100 4101 // Adjust the APSInt value. 4102 InitVal.extOrTrunc(NewWidth); 4103 InitVal.setIsSigned(NewSign); 4104 ECD->setInitVal(InitVal); 4105 4106 // Adjust the Expr initializer and type. 4107 if (ECD->getInitExpr()) 4108 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4109 /*isLvalue=*/false)); 4110 if (getLangOptions().CPlusPlus) 4111 // C++ [dcl.enum]p4: Following the closing brace of an 4112 // enum-specifier, each enumerator has the type of its 4113 // enumeration. 4114 ECD->setType(EnumType); 4115 else 4116 ECD->setType(NewTy); 4117 } 4118 4119 Enum->completeDefinition(Context, BestType); 4120} 4121 4122Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4123 ExprArg expr) { 4124 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4125 4126 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 4127} 4128 4129