SemaDecl.cpp revision d553d4cb957f23bb129d3174108a1ee6d54a1e4a
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 /*hasPrototype=*/true); 339 New->setImplicit(); 340 341 // Create Decl objects for each parameter, adding them to the 342 // FunctionDecl. 343 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 344 llvm::SmallVector<ParmVarDecl*, 16> Params; 345 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 346 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 347 FT->getArgType(i), VarDecl::None, 0)); 348 New->setParams(Context, &Params[0], Params.size()); 349 } 350 351 AddKnownFunctionAttributes(New); 352 353 // TUScope is the translation-unit scope to insert this function into. 354 // FIXME: This is hideous. We need to teach PushOnScopeChains to 355 // relate Scopes to DeclContexts, and probably eliminate CurContext 356 // entirely, but we're not there yet. 357 DeclContext *SavedContext = CurContext; 358 CurContext = Context.getTranslationUnitDecl(); 359 PushOnScopeChains(New, TUScope); 360 CurContext = SavedContext; 361 return New; 362} 363 364/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 365/// everything from the standard library is defined. 366NamespaceDecl *Sema::GetStdNamespace() { 367 if (!StdNamespace) { 368 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 369 DeclContext *Global = Context.getTranslationUnitDecl(); 370 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 371 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 372 } 373 return StdNamespace; 374} 375 376/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 377/// same name and scope as a previous declaration 'Old'. Figure out 378/// how to resolve this situation, merging decls or emitting 379/// diagnostics as appropriate. Returns true if there was an error, 380/// false otherwise. 381/// 382bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 383 bool objc_types = false; 384 // Allow multiple definitions for ObjC built-in typedefs. 385 // FIXME: Verify the underlying types are equivalent! 386 if (getLangOptions().ObjC1) { 387 const IdentifierInfo *TypeID = New->getIdentifier(); 388 switch (TypeID->getLength()) { 389 default: break; 390 case 2: 391 if (!TypeID->isStr("id")) 392 break; 393 Context.setObjCIdType(New); 394 objc_types = true; 395 break; 396 case 5: 397 if (!TypeID->isStr("Class")) 398 break; 399 Context.setObjCClassType(New); 400 objc_types = true; 401 return false; 402 case 3: 403 if (!TypeID->isStr("SEL")) 404 break; 405 Context.setObjCSelType(New); 406 objc_types = true; 407 return false; 408 case 8: 409 if (!TypeID->isStr("Protocol")) 410 break; 411 Context.setObjCProtoType(New->getUnderlyingType()); 412 objc_types = true; 413 return false; 414 } 415 // Fall through - the typedef name was not a builtin type. 416 } 417 // Verify the old decl was also a type. 418 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 419 if (!Old) { 420 Diag(New->getLocation(), diag::err_redefinition_different_kind) 421 << New->getDeclName(); 422 if (!objc_types) 423 Diag(OldD->getLocation(), diag::note_previous_definition); 424 return true; 425 } 426 427 // Determine the "old" type we'll use for checking and diagnostics. 428 QualType OldType; 429 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 430 OldType = OldTypedef->getUnderlyingType(); 431 else 432 OldType = Context.getTypeDeclType(Old); 433 434 // If the typedef types are not identical, reject them in all languages and 435 // with any extensions enabled. 436 437 if (OldType != New->getUnderlyingType() && 438 Context.getCanonicalType(OldType) != 439 Context.getCanonicalType(New->getUnderlyingType())) { 440 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 441 << New->getUnderlyingType() << OldType; 442 if (!objc_types) 443 Diag(Old->getLocation(), diag::note_previous_definition); 444 return true; 445 } 446 if (objc_types) return false; 447 if (getLangOptions().Microsoft) return false; 448 449 // C++ [dcl.typedef]p2: 450 // In a given non-class scope, a typedef specifier can be used to 451 // redefine the name of any type declared in that scope to refer 452 // to the type to which it already refers. 453 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 454 return false; 455 456 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 457 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 458 // *either* declaration is in a system header. The code below implements 459 // this adhoc compatibility rule. FIXME: The following code will not 460 // work properly when compiling ".i" files (containing preprocessed output). 461 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 462 SourceManager &SrcMgr = Context.getSourceManager(); 463 if (SrcMgr.isInSystemHeader(Old->getLocation())) 464 return false; 465 if (SrcMgr.isInSystemHeader(New->getLocation())) 466 return false; 467 } 468 469 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 470 Diag(Old->getLocation(), diag::note_previous_definition); 471 return true; 472} 473 474/// DeclhasAttr - returns true if decl Declaration already has the target 475/// attribute. 476static bool DeclHasAttr(const Decl *decl, const Attr *target) { 477 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 478 if (attr->getKind() == target->getKind()) 479 return true; 480 481 return false; 482} 483 484/// MergeAttributes - append attributes from the Old decl to the New one. 485static void MergeAttributes(Decl *New, Decl *Old) { 486 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 487 488 while (attr) { 489 tmp = attr; 490 attr = attr->getNext(); 491 492 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 493 tmp->setInherited(true); 494 New->addAttr(tmp); 495 } else { 496 tmp->setNext(0); 497 delete(tmp); 498 } 499 } 500 501 Old->invalidateAttrs(); 502} 503 504/// MergeFunctionDecl - We just parsed a function 'New' from 505/// declarator D which has the same name and scope as a previous 506/// declaration 'Old'. Figure out how to resolve this situation, 507/// merging decls or emitting diagnostics as appropriate. 508/// 509/// In C++, New and Old must be declarations that are not 510/// overloaded. Use IsOverload to determine whether New and Old are 511/// overloaded, and to select the Old declaration that New should be 512/// merged with. 513/// 514/// Returns true if there was an error, false otherwise. 515bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 516 assert(!isa<OverloadedFunctionDecl>(OldD) && 517 "Cannot merge with an overloaded function declaration"); 518 519 // Verify the old decl was also a function. 520 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 521 if (!Old) { 522 Diag(New->getLocation(), diag::err_redefinition_different_kind) 523 << New->getDeclName(); 524 Diag(OldD->getLocation(), diag::note_previous_definition); 525 return true; 526 } 527 528 // Determine whether the previous declaration was a definition, 529 // implicit declaration, or a declaration. 530 diag::kind PrevDiag; 531 if (Old->isThisDeclarationADefinition()) 532 PrevDiag = diag::note_previous_definition; 533 else if (Old->isImplicit()) 534 PrevDiag = diag::note_previous_implicit_declaration; 535 else 536 PrevDiag = diag::note_previous_declaration; 537 538 QualType OldQType = Context.getCanonicalType(Old->getType()); 539 QualType NewQType = Context.getCanonicalType(New->getType()); 540 541 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 542 New->getStorageClass() == FunctionDecl::Static && 543 Old->getStorageClass() != FunctionDecl::Static) { 544 Diag(New->getLocation(), diag::err_static_non_static) 545 << New; 546 Diag(Old->getLocation(), PrevDiag); 547 return true; 548 } 549 550 if (getLangOptions().CPlusPlus) { 551 // (C++98 13.1p2): 552 // Certain function declarations cannot be overloaded: 553 // -- Function declarations that differ only in the return type 554 // cannot be overloaded. 555 QualType OldReturnType 556 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 557 QualType NewReturnType 558 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 559 if (OldReturnType != NewReturnType) { 560 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 561 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 562 return true; 563 } 564 565 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 566 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 567 if (OldMethod && NewMethod) { 568 // -- Member function declarations with the same name and the 569 // same parameter types cannot be overloaded if any of them 570 // is a static member function declaration. 571 if (OldMethod->isStatic() || NewMethod->isStatic()) { 572 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 573 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 574 return true; 575 } 576 577 // C++ [class.mem]p1: 578 // [...] A member shall not be declared twice in the 579 // member-specification, except that a nested class or member 580 // class template can be declared and then later defined. 581 if (OldMethod->getLexicalDeclContext() == 582 NewMethod->getLexicalDeclContext()) { 583 unsigned NewDiag; 584 if (isa<CXXConstructorDecl>(OldMethod)) 585 NewDiag = diag::err_constructor_redeclared; 586 else if (isa<CXXDestructorDecl>(NewMethod)) 587 NewDiag = diag::err_destructor_redeclared; 588 else if (isa<CXXConversionDecl>(NewMethod)) 589 NewDiag = diag::err_conv_function_redeclared; 590 else 591 NewDiag = diag::err_member_redeclared; 592 593 Diag(New->getLocation(), NewDiag); 594 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 595 } 596 } 597 598 // (C++98 8.3.5p3): 599 // All declarations for a function shall agree exactly in both the 600 // return type and the parameter-type-list. 601 if (OldQType == NewQType) 602 return MergeCompatibleFunctionDecls(New, Old); 603 604 // Fall through for conflicting redeclarations and redefinitions. 605 } 606 607 // C: Function types need to be compatible, not identical. This handles 608 // duplicate function decls like "void f(int); void f(enum X);" properly. 609 if (!getLangOptions().CPlusPlus && 610 Context.typesAreCompatible(OldQType, NewQType)) { 611 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 612 const FunctionTypeProto *OldProto = 0; 613 if (isa<FunctionTypeNoProto>(NewFuncType) && 614 (OldProto = OldQType->getAsFunctionTypeProto())) { 615 // The old declaration provided a function prototype, but the 616 // new declaration does not. Merge in the prototype. 617 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 618 OldProto->arg_type_end()); 619 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 620 &ParamTypes[0], ParamTypes.size(), 621 OldProto->isVariadic(), 622 OldProto->getTypeQuals()); 623 New->setType(NewQType); 624 New->setInheritedPrototype(); 625 626 // Synthesize a parameter for each argument type. 627 llvm::SmallVector<ParmVarDecl*, 16> Params; 628 for (FunctionTypeProto::arg_type_iterator 629 ParamType = OldProto->arg_type_begin(), 630 ParamEnd = OldProto->arg_type_end(); 631 ParamType != ParamEnd; ++ParamType) { 632 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 633 SourceLocation(), 0, 634 *ParamType, VarDecl::None, 635 0); 636 Param->setImplicit(); 637 Params.push_back(Param); 638 } 639 640 New->setParams(Context, &Params[0], Params.size()); 641 642 } 643 644 return MergeCompatibleFunctionDecls(New, Old); 645 } 646 647 // A function that has already been declared has been redeclared or defined 648 // with a different type- show appropriate diagnostic 649 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 650 // The user has declared a builtin function with an incompatible 651 // signature. 652 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 653 // The function the user is redeclaring is a library-defined 654 // function like 'malloc' or 'printf'. Warn about the 655 // redeclaration, then ignore it. 656 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 657 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 658 << Old << Old->getType(); 659 return true; 660 } 661 662 PrevDiag = diag::note_previous_builtin_declaration; 663 } 664 665 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 666 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 667 return true; 668} 669 670/// \brief Completes the merge of two function declarations that are 671/// known to be compatible. 672/// 673/// This routine handles the merging of attributes and other 674/// properties of function declarations form the old declaration to 675/// the new declaration, once we know that New is in fact a 676/// redeclaration of Old. 677/// 678/// \returns false 679bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 680 // Merge the attributes 681 MergeAttributes(New, Old); 682 683 // Merge the storage class. 684 New->setStorageClass(Old->getStorageClass()); 685 686 // FIXME: need to implement inline semantics 687 688 // Merge "pure" flag. 689 if (Old->isPure()) 690 New->setPure(); 691 692 // Merge the "deleted" flag. 693 if (Old->isDeleted()) 694 New->setDeleted(); 695 696 if (getLangOptions().CPlusPlus) 697 return MergeCXXFunctionDecl(New, Old); 698 699 return false; 700} 701 702/// Predicate for C "tentative" external object definitions (C99 6.9.2). 703static bool isTentativeDefinition(VarDecl *VD) { 704 if (VD->isFileVarDecl()) 705 return (!VD->getInit() && 706 (VD->getStorageClass() == VarDecl::None || 707 VD->getStorageClass() == VarDecl::Static)); 708 return false; 709} 710 711/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 712/// when dealing with C "tentative" external object definitions (C99 6.9.2). 713void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 714 bool VDIsTentative = isTentativeDefinition(VD); 715 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 716 717 // FIXME: I don't think this will actually see all of the 718 // redefinitions. Can't we check this property on-the-fly? 719 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 720 E = IdResolver.end(); 721 I != E; ++I) { 722 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 723 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 724 725 // Handle the following case: 726 // int a[10]; 727 // int a[]; - the code below makes sure we set the correct type. 728 // int a[11]; - this is an error, size isn't 10. 729 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 730 OldDecl->getType()->isConstantArrayType()) 731 VD->setType(OldDecl->getType()); 732 733 // Check for "tentative" definitions. We can't accomplish this in 734 // MergeVarDecl since the initializer hasn't been attached. 735 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 736 continue; 737 738 // Handle __private_extern__ just like extern. 739 if (OldDecl->getStorageClass() != VarDecl::Extern && 740 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 741 VD->getStorageClass() != VarDecl::Extern && 742 VD->getStorageClass() != VarDecl::PrivateExtern) { 743 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 744 Diag(OldDecl->getLocation(), diag::note_previous_definition); 745 // One redefinition error is enough. 746 break; 747 } 748 } 749 } 750} 751 752/// MergeVarDecl - We just parsed a variable 'New' which has the same name 753/// and scope as a previous declaration 'Old'. Figure out how to resolve this 754/// situation, merging decls or emitting diagnostics as appropriate. 755/// 756/// Tentative definition rules (C99 6.9.2p2) are checked by 757/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 758/// definitions here, since the initializer hasn't been attached. 759/// 760bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 761 // Verify the old decl was also a variable. 762 VarDecl *Old = dyn_cast<VarDecl>(OldD); 763 if (!Old) { 764 Diag(New->getLocation(), diag::err_redefinition_different_kind) 765 << New->getDeclName(); 766 Diag(OldD->getLocation(), diag::note_previous_definition); 767 return true; 768 } 769 770 MergeAttributes(New, Old); 771 772 // Merge the types 773 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 774 if (MergedT.isNull()) { 775 Diag(New->getLocation(), diag::err_redefinition_different_type) 776 << New->getDeclName(); 777 Diag(Old->getLocation(), diag::note_previous_definition); 778 return true; 779 } 780 New->setType(MergedT); 781 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 782 if (New->getStorageClass() == VarDecl::Static && 783 (Old->getStorageClass() == VarDecl::None || 784 Old->getStorageClass() == VarDecl::Extern)) { 785 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 786 Diag(Old->getLocation(), diag::note_previous_definition); 787 return true; 788 } 789 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 790 if (New->getStorageClass() != VarDecl::Static && 791 Old->getStorageClass() == VarDecl::Static) { 792 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 793 Diag(Old->getLocation(), diag::note_previous_definition); 794 return true; 795 } 796 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 797 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 798 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 799 Diag(Old->getLocation(), diag::note_previous_definition); 800 return true; 801 } 802 return false; 803} 804 805/// CheckParmsForFunctionDef - Check that the parameters of the given 806/// function are appropriate for the definition of a function. This 807/// takes care of any checks that cannot be performed on the 808/// declaration itself, e.g., that the types of each of the function 809/// parameters are complete. 810bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 811 bool HasInvalidParm = false; 812 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 813 ParmVarDecl *Param = FD->getParamDecl(p); 814 815 // C99 6.7.5.3p4: the parameters in a parameter type list in a 816 // function declarator that is part of a function definition of 817 // that function shall not have incomplete type. 818 if (!Param->isInvalidDecl() && 819 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 820 diag::err_typecheck_decl_incomplete_type)) { 821 Param->setInvalidDecl(); 822 HasInvalidParm = true; 823 } 824 825 // C99 6.9.1p5: If the declarator includes a parameter type list, the 826 // declaration of each parameter shall include an identifier. 827 if (Param->getIdentifier() == 0 && 828 !Param->isImplicit() && 829 !getLangOptions().CPlusPlus) 830 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 831 } 832 833 return HasInvalidParm; 834} 835 836/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 837/// no declarator (e.g. "struct foo;") is parsed. 838Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 839 TagDecl *Tag = 0; 840 if (DS.getTypeSpecType() == DeclSpec::TST_class || 841 DS.getTypeSpecType() == DeclSpec::TST_struct || 842 DS.getTypeSpecType() == DeclSpec::TST_union || 843 DS.getTypeSpecType() == DeclSpec::TST_enum) 844 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 845 846 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 847 if (!Record->getDeclName() && Record->isDefinition() && 848 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 849 return BuildAnonymousStructOrUnion(S, DS, Record); 850 851 // Microsoft allows unnamed struct/union fields. Don't complain 852 // about them. 853 // FIXME: Should we support Microsoft's extensions in this area? 854 if (Record->getDeclName() && getLangOptions().Microsoft) 855 return Tag; 856 } 857 858 if (!DS.isMissingDeclaratorOk() && 859 DS.getTypeSpecType() != DeclSpec::TST_error) { 860 // Warn about typedefs of enums without names, since this is an 861 // extension in both Microsoft an GNU. 862 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 863 Tag && isa<EnumDecl>(Tag)) { 864 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 865 << DS.getSourceRange(); 866 return Tag; 867 } 868 869 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 870 << DS.getSourceRange(); 871 return 0; 872 } 873 874 return Tag; 875} 876 877/// InjectAnonymousStructOrUnionMembers - Inject the members of the 878/// anonymous struct or union AnonRecord into the owning context Owner 879/// and scope S. This routine will be invoked just after we realize 880/// that an unnamed union or struct is actually an anonymous union or 881/// struct, e.g., 882/// 883/// @code 884/// union { 885/// int i; 886/// float f; 887/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 888/// // f into the surrounding scope.x 889/// @endcode 890/// 891/// This routine is recursive, injecting the names of nested anonymous 892/// structs/unions into the owning context and scope as well. 893bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 894 RecordDecl *AnonRecord) { 895 bool Invalid = false; 896 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 897 FEnd = AnonRecord->field_end(); 898 F != FEnd; ++F) { 899 if ((*F)->getDeclName()) { 900 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 901 LookupOrdinaryName, true); 902 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 903 // C++ [class.union]p2: 904 // The names of the members of an anonymous union shall be 905 // distinct from the names of any other entity in the 906 // scope in which the anonymous union is declared. 907 unsigned diagKind 908 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 909 : diag::err_anonymous_struct_member_redecl; 910 Diag((*F)->getLocation(), diagKind) 911 << (*F)->getDeclName(); 912 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 913 Invalid = true; 914 } else { 915 // C++ [class.union]p2: 916 // For the purpose of name lookup, after the anonymous union 917 // definition, the members of the anonymous union are 918 // considered to have been defined in the scope in which the 919 // anonymous union is declared. 920 Owner->makeDeclVisibleInContext(*F); 921 S->AddDecl(*F); 922 IdResolver.AddDecl(*F); 923 } 924 } else if (const RecordType *InnerRecordType 925 = (*F)->getType()->getAsRecordType()) { 926 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 927 if (InnerRecord->isAnonymousStructOrUnion()) 928 Invalid = Invalid || 929 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 930 } 931 } 932 933 return Invalid; 934} 935 936/// ActOnAnonymousStructOrUnion - Handle the declaration of an 937/// anonymous structure or union. Anonymous unions are a C++ feature 938/// (C++ [class.union]) and a GNU C extension; anonymous structures 939/// are a GNU C and GNU C++ extension. 940Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 941 RecordDecl *Record) { 942 DeclContext *Owner = Record->getDeclContext(); 943 944 // Diagnose whether this anonymous struct/union is an extension. 945 if (Record->isUnion() && !getLangOptions().CPlusPlus) 946 Diag(Record->getLocation(), diag::ext_anonymous_union); 947 else if (!Record->isUnion()) 948 Diag(Record->getLocation(), diag::ext_anonymous_struct); 949 950 // C and C++ require different kinds of checks for anonymous 951 // structs/unions. 952 bool Invalid = false; 953 if (getLangOptions().CPlusPlus) { 954 const char* PrevSpec = 0; 955 // C++ [class.union]p3: 956 // Anonymous unions declared in a named namespace or in the 957 // global namespace shall be declared static. 958 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 959 (isa<TranslationUnitDecl>(Owner) || 960 (isa<NamespaceDecl>(Owner) && 961 cast<NamespaceDecl>(Owner)->getDeclName()))) { 962 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 963 Invalid = true; 964 965 // Recover by adding 'static'. 966 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 967 } 968 // C++ [class.union]p3: 969 // A storage class is not allowed in a declaration of an 970 // anonymous union in a class scope. 971 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 972 isa<RecordDecl>(Owner)) { 973 Diag(DS.getStorageClassSpecLoc(), 974 diag::err_anonymous_union_with_storage_spec); 975 Invalid = true; 976 977 // Recover by removing the storage specifier. 978 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 979 PrevSpec); 980 } 981 982 // C++ [class.union]p2: 983 // The member-specification of an anonymous union shall only 984 // define non-static data members. [Note: nested types and 985 // functions cannot be declared within an anonymous union. ] 986 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 987 MemEnd = Record->decls_end(); 988 Mem != MemEnd; ++Mem) { 989 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 990 // C++ [class.union]p3: 991 // An anonymous union shall not have private or protected 992 // members (clause 11). 993 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 994 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 995 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 996 Invalid = true; 997 } 998 } else if ((*Mem)->isImplicit()) { 999 // Any implicit members are fine. 1000 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1001 // This is a type that showed up in an 1002 // elaborated-type-specifier inside the anonymous struct or 1003 // union, but which actually declares a type outside of the 1004 // anonymous struct or union. It's okay. 1005 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1006 if (!MemRecord->isAnonymousStructOrUnion() && 1007 MemRecord->getDeclName()) { 1008 // This is a nested type declaration. 1009 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1010 << (int)Record->isUnion(); 1011 Invalid = true; 1012 } 1013 } else { 1014 // We have something that isn't a non-static data 1015 // member. Complain about it. 1016 unsigned DK = diag::err_anonymous_record_bad_member; 1017 if (isa<TypeDecl>(*Mem)) 1018 DK = diag::err_anonymous_record_with_type; 1019 else if (isa<FunctionDecl>(*Mem)) 1020 DK = diag::err_anonymous_record_with_function; 1021 else if (isa<VarDecl>(*Mem)) 1022 DK = diag::err_anonymous_record_with_static; 1023 Diag((*Mem)->getLocation(), DK) 1024 << (int)Record->isUnion(); 1025 Invalid = true; 1026 } 1027 } 1028 } else { 1029 // FIXME: Check GNU C semantics 1030 if (Record->isUnion() && !Owner->isRecord()) { 1031 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 1032 << (int)getLangOptions().CPlusPlus; 1033 Invalid = true; 1034 } 1035 } 1036 1037 if (!Record->isUnion() && !Owner->isRecord()) { 1038 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1039 << (int)getLangOptions().CPlusPlus; 1040 Invalid = true; 1041 } 1042 1043 // Create a declaration for this anonymous struct/union. 1044 NamedDecl *Anon = 0; 1045 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1046 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1047 /*IdentifierInfo=*/0, 1048 Context.getTypeDeclType(Record), 1049 /*BitWidth=*/0, /*Mutable=*/false); 1050 Anon->setAccess(AS_public); 1051 if (getLangOptions().CPlusPlus) 1052 FieldCollector->Add(cast<FieldDecl>(Anon)); 1053 } else { 1054 VarDecl::StorageClass SC; 1055 switch (DS.getStorageClassSpec()) { 1056 default: assert(0 && "Unknown storage class!"); 1057 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1058 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1059 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1060 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1061 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1062 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1063 case DeclSpec::SCS_mutable: 1064 // mutable can only appear on non-static class members, so it's always 1065 // an error here 1066 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1067 Invalid = true; 1068 SC = VarDecl::None; 1069 break; 1070 } 1071 1072 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1073 /*IdentifierInfo=*/0, 1074 Context.getTypeDeclType(Record), 1075 SC, DS.getSourceRange().getBegin()); 1076 } 1077 Anon->setImplicit(); 1078 1079 // Add the anonymous struct/union object to the current 1080 // context. We'll be referencing this object when we refer to one of 1081 // its members. 1082 Owner->addDecl(Anon); 1083 1084 // Inject the members of the anonymous struct/union into the owning 1085 // context and into the identifier resolver chain for name lookup 1086 // purposes. 1087 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1088 Invalid = true; 1089 1090 // Mark this as an anonymous struct/union type. Note that we do not 1091 // do this until after we have already checked and injected the 1092 // members of this anonymous struct/union type, because otherwise 1093 // the members could be injected twice: once by DeclContext when it 1094 // builds its lookup table, and once by 1095 // InjectAnonymousStructOrUnionMembers. 1096 Record->setAnonymousStructOrUnion(true); 1097 1098 if (Invalid) 1099 Anon->setInvalidDecl(); 1100 1101 return Anon; 1102} 1103 1104 1105/// GetNameForDeclarator - Determine the full declaration name for the 1106/// given Declarator. 1107DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1108 switch (D.getKind()) { 1109 case Declarator::DK_Abstract: 1110 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1111 return DeclarationName(); 1112 1113 case Declarator::DK_Normal: 1114 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1115 return DeclarationName(D.getIdentifier()); 1116 1117 case Declarator::DK_Constructor: { 1118 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1119 Ty = Context.getCanonicalType(Ty); 1120 return Context.DeclarationNames.getCXXConstructorName(Ty); 1121 } 1122 1123 case Declarator::DK_Destructor: { 1124 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1125 Ty = Context.getCanonicalType(Ty); 1126 return Context.DeclarationNames.getCXXDestructorName(Ty); 1127 } 1128 1129 case Declarator::DK_Conversion: { 1130 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1131 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1132 Ty = Context.getCanonicalType(Ty); 1133 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1134 } 1135 1136 case Declarator::DK_Operator: 1137 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1138 return Context.DeclarationNames.getCXXOperatorName( 1139 D.getOverloadedOperator()); 1140 } 1141 1142 assert(false && "Unknown name kind"); 1143 return DeclarationName(); 1144} 1145 1146/// isNearlyMatchingFunction - Determine whether the C++ functions 1147/// Declaration and Definition are "nearly" matching. This heuristic 1148/// is used to improve diagnostics in the case where an out-of-line 1149/// function definition doesn't match any declaration within 1150/// the class or namespace. 1151static bool isNearlyMatchingFunction(ASTContext &Context, 1152 FunctionDecl *Declaration, 1153 FunctionDecl *Definition) { 1154 if (Declaration->param_size() != Definition->param_size()) 1155 return false; 1156 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1157 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1158 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1159 1160 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1161 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1162 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1163 return false; 1164 } 1165 1166 return true; 1167} 1168 1169Sema::DeclTy * 1170Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1171 bool IsFunctionDefinition) { 1172 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1173 DeclarationName Name = GetNameForDeclarator(D); 1174 1175 // All of these full declarators require an identifier. If it doesn't have 1176 // one, the ParsedFreeStandingDeclSpec action should be used. 1177 if (!Name) { 1178 if (!D.getInvalidType()) // Reject this if we think it is valid. 1179 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1180 diag::err_declarator_need_ident) 1181 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1182 return 0; 1183 } 1184 1185 // The scope passed in may not be a decl scope. Zip up the scope tree until 1186 // we find one that is. 1187 while ((S->getFlags() & Scope::DeclScope) == 0 || 1188 (S->getFlags() & Scope::TemplateParamScope) != 0) 1189 S = S->getParent(); 1190 1191 DeclContext *DC; 1192 NamedDecl *PrevDecl; 1193 NamedDecl *New; 1194 bool InvalidDecl = false; 1195 1196 QualType R = GetTypeForDeclarator(D, S); 1197 if (R.isNull()) { 1198 InvalidDecl = true; 1199 R = Context.IntTy; 1200 } 1201 1202 // See if this is a redefinition of a variable in the same scope. 1203 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1204 LookupNameKind NameKind = LookupOrdinaryName; 1205 1206 // If the declaration we're planning to build will be a function 1207 // or object with linkage, then look for another declaration with 1208 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1209 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1210 /* Do nothing*/; 1211 else if (R->isFunctionType()) { 1212 if (CurContext->isFunctionOrMethod()) 1213 NameKind = LookupRedeclarationWithLinkage; 1214 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1215 NameKind = LookupRedeclarationWithLinkage; 1216 1217 DC = CurContext; 1218 PrevDecl = LookupName(S, Name, NameKind, true, 1219 D.getDeclSpec().getStorageClassSpec() != 1220 DeclSpec::SCS_static, 1221 D.getIdentifierLoc()); 1222 } else { // Something like "int foo::x;" 1223 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1224 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1225 1226 // C++ 7.3.1.2p2: 1227 // Members (including explicit specializations of templates) of a named 1228 // namespace can also be defined outside that namespace by explicit 1229 // qualification of the name being defined, provided that the entity being 1230 // defined was already declared in the namespace and the definition appears 1231 // after the point of declaration in a namespace that encloses the 1232 // declarations namespace. 1233 // 1234 // Note that we only check the context at this point. We don't yet 1235 // have enough information to make sure that PrevDecl is actually 1236 // the declaration we want to match. For example, given: 1237 // 1238 // class X { 1239 // void f(); 1240 // void f(float); 1241 // }; 1242 // 1243 // void X::f(int) { } // ill-formed 1244 // 1245 // In this case, PrevDecl will point to the overload set 1246 // containing the two f's declared in X, but neither of them 1247 // matches. 1248 1249 // First check whether we named the global scope. 1250 if (isa<TranslationUnitDecl>(DC)) { 1251 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1252 << Name << D.getCXXScopeSpec().getRange(); 1253 } else if (!CurContext->Encloses(DC)) { 1254 // The qualifying scope doesn't enclose the original declaration. 1255 // Emit diagnostic based on current scope. 1256 SourceLocation L = D.getIdentifierLoc(); 1257 SourceRange R = D.getCXXScopeSpec().getRange(); 1258 if (isa<FunctionDecl>(CurContext)) 1259 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1260 else 1261 Diag(L, diag::err_invalid_declarator_scope) 1262 << Name << cast<NamedDecl>(DC) << R; 1263 InvalidDecl = true; 1264 } 1265 } 1266 1267 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1268 // Maybe we will complain about the shadowed template parameter. 1269 InvalidDecl = InvalidDecl 1270 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1271 // Just pretend that we didn't see the previous declaration. 1272 PrevDecl = 0; 1273 } 1274 1275 // In C++, the previous declaration we find might be a tag type 1276 // (class or enum). In this case, the new declaration will hide the 1277 // tag type. Note that this does does not apply if we're declaring a 1278 // typedef (C++ [dcl.typedef]p4). 1279 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1280 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1281 PrevDecl = 0; 1282 1283 bool Redeclaration = false; 1284 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1285 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1286 InvalidDecl, Redeclaration); 1287 } else if (R->isFunctionType()) { 1288 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1289 IsFunctionDefinition, InvalidDecl, 1290 Redeclaration); 1291 } else { 1292 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1293 InvalidDecl, Redeclaration); 1294 } 1295 1296 if (New == 0) 1297 return 0; 1298 1299 // Set the lexical context. If the declarator has a C++ scope specifier, the 1300 // lexical context will be different from the semantic context. 1301 New->setLexicalDeclContext(CurContext); 1302 1303 // If this has an identifier and is not an invalid redeclaration, 1304 // add it to the scope stack. 1305 if (Name && !(Redeclaration && InvalidDecl)) 1306 PushOnScopeChains(New, S); 1307 // If any semantic error occurred, mark the decl as invalid. 1308 if (D.getInvalidType() || InvalidDecl) 1309 New->setInvalidDecl(); 1310 1311 return New; 1312} 1313 1314/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1315/// types into constant array types in certain situations which would otherwise 1316/// be errors (for GCC compatibility). 1317static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1318 ASTContext &Context, 1319 bool &SizeIsNegative) { 1320 // This method tries to turn a variable array into a constant 1321 // array even when the size isn't an ICE. This is necessary 1322 // for compatibility with code that depends on gcc's buggy 1323 // constant expression folding, like struct {char x[(int)(char*)2];} 1324 SizeIsNegative = false; 1325 1326 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1327 QualType Pointee = PTy->getPointeeType(); 1328 QualType FixedType = 1329 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1330 if (FixedType.isNull()) return FixedType; 1331 FixedType = Context.getPointerType(FixedType); 1332 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1333 return FixedType; 1334 } 1335 1336 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1337 if (!VLATy) 1338 return QualType(); 1339 // FIXME: We should probably handle this case 1340 if (VLATy->getElementType()->isVariablyModifiedType()) 1341 return QualType(); 1342 1343 Expr::EvalResult EvalResult; 1344 if (!VLATy->getSizeExpr() || 1345 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1346 !EvalResult.Val.isInt()) 1347 return QualType(); 1348 1349 llvm::APSInt &Res = EvalResult.Val.getInt(); 1350 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1351 return Context.getConstantArrayType(VLATy->getElementType(), 1352 Res, ArrayType::Normal, 0); 1353 1354 SizeIsNegative = true; 1355 return QualType(); 1356} 1357 1358NamedDecl* 1359Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1360 QualType R, Decl* LastDeclarator, 1361 Decl* PrevDecl, bool& InvalidDecl, 1362 bool &Redeclaration) { 1363 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1364 if (D.getCXXScopeSpec().isSet()) { 1365 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1366 << D.getCXXScopeSpec().getRange(); 1367 InvalidDecl = true; 1368 // Pretend we didn't see the scope specifier. 1369 DC = 0; 1370 } 1371 1372 // Check that there are no default arguments (C++ only). 1373 if (getLangOptions().CPlusPlus) 1374 CheckExtraCXXDefaultArguments(D); 1375 1376 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1377 if (!NewTD) return 0; 1378 1379 // Handle attributes prior to checking for duplicates in MergeVarDecl 1380 ProcessDeclAttributes(NewTD, D); 1381 // Merge the decl with the existing one if appropriate. If the decl is 1382 // in an outer scope, it isn't the same thing. 1383 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1384 Redeclaration = true; 1385 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1386 InvalidDecl = true; 1387 } 1388 1389 if (S->getFnParent() == 0) { 1390 QualType T = NewTD->getUnderlyingType(); 1391 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1392 // then it shall have block scope. 1393 if (T->isVariablyModifiedType()) { 1394 bool SizeIsNegative; 1395 QualType FixedTy = 1396 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1397 if (!FixedTy.isNull()) { 1398 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1399 NewTD->setUnderlyingType(FixedTy); 1400 } else { 1401 if (SizeIsNegative) 1402 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1403 else if (T->isVariableArrayType()) 1404 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1405 else 1406 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1407 InvalidDecl = true; 1408 } 1409 } 1410 } 1411 return NewTD; 1412} 1413 1414/// \brief Determines whether the given declaration is an out-of-scope 1415/// previous declaration. 1416/// 1417/// This routine should be invoked when name lookup has found a 1418/// previous declaration (PrevDecl) that is not in the scope where a 1419/// new declaration by the same name is being introduced. If the new 1420/// declaration occurs in a local scope, previous declarations with 1421/// linkage may still be considered previous declarations (C99 1422/// 6.2.2p4-5, C++ [basic.link]p6). 1423/// 1424/// \param PrevDecl the previous declaration found by name 1425/// lookup 1426/// 1427/// \param DC the context in which the new declaration is being 1428/// declared. 1429/// 1430/// \returns true if PrevDecl is an out-of-scope previous declaration 1431/// for a new delcaration with the same name. 1432static bool 1433isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1434 ASTContext &Context) { 1435 if (!PrevDecl) 1436 return 0; 1437 1438 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1439 // case we need to check each of the overloaded functions. 1440 if (!PrevDecl->hasLinkage()) 1441 return false; 1442 1443 if (Context.getLangOptions().CPlusPlus) { 1444 // C++ [basic.link]p6: 1445 // If there is a visible declaration of an entity with linkage 1446 // having the same name and type, ignoring entities declared 1447 // outside the innermost enclosing namespace scope, the block 1448 // scope declaration declares that same entity and receives the 1449 // linkage of the previous declaration. 1450 DeclContext *OuterContext = DC->getLookupContext(); 1451 if (!OuterContext->isFunctionOrMethod()) 1452 // This rule only applies to block-scope declarations. 1453 return false; 1454 else { 1455 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1456 if (PrevOuterContext->isRecord()) 1457 // We found a member function: ignore it. 1458 return false; 1459 else { 1460 // Find the innermost enclosing namespace for the new and 1461 // previous declarations. 1462 while (!OuterContext->isFileContext()) 1463 OuterContext = OuterContext->getParent(); 1464 while (!PrevOuterContext->isFileContext()) 1465 PrevOuterContext = PrevOuterContext->getParent(); 1466 1467 // The previous declaration is in a different namespace, so it 1468 // isn't the same function. 1469 if (OuterContext->getPrimaryContext() != 1470 PrevOuterContext->getPrimaryContext()) 1471 return false; 1472 } 1473 } 1474 } 1475 1476 return true; 1477} 1478 1479/// \brief Inject a locally-scoped declaration with external linkage 1480/// into the appropriate namespace scope. 1481/// 1482/// Given a declaration of an entity with linkage that occurs within a 1483/// local scope, this routine inject that declaration into top-level 1484/// scope so that it will be visible for later uses and declarations 1485/// of the same entity. 1486void Sema::InjectLocallyScopedExternalDeclaration(ValueDecl *VD) { 1487 // FIXME: We don't do this in C++ because, although we would like 1488 // to get the extra checking that this operation implies, 1489 // the declaration itself is not visible according to C++'s rules. 1490 assert(!getLangOptions().CPlusPlus && 1491 "Can't inject locally-scoped declarations in C++"); 1492 IdentifierResolver::iterator I = IdResolver.begin(VD->getDeclName()), 1493 IEnd = IdResolver.end(); 1494 NamedDecl *PrevDecl = 0; 1495 while (I != IEnd && !isa<TranslationUnitDecl>((*I)->getDeclContext())) { 1496 PrevDecl = *I; 1497 ++I; 1498 } 1499 1500 if (I == IEnd) { 1501 // No name with this identifier has been declared at translation 1502 // unit scope. Add this name into the appropriate scope. 1503 if (PrevDecl) 1504 IdResolver.AddShadowedDecl(VD, PrevDecl); 1505 else 1506 IdResolver.AddDecl(VD); 1507 TUScope->AddDecl(VD); 1508 return; 1509 } 1510 1511 if (isa<TagDecl>(*I)) { 1512 // The first thing we found was a tag declaration, so insert 1513 // this function so that it will be found before the tag 1514 // declaration. 1515 if (PrevDecl) 1516 IdResolver.AddShadowedDecl(VD, PrevDecl); 1517 else 1518 IdResolver.AddDecl(VD); 1519 TUScope->AddDecl(VD); 1520 return; 1521 } 1522 1523 if (VD->declarationReplaces(*I)) { 1524 // We found a previous declaration of the same entity. Replace 1525 // that declaration with this one. 1526 TUScope->RemoveDecl(*I); 1527 TUScope->AddDecl(VD); 1528 IdResolver.RemoveDecl(*I); 1529 if (PrevDecl) 1530 IdResolver.AddShadowedDecl(VD, PrevDecl); 1531 else 1532 IdResolver.AddDecl(VD); 1533 } 1534} 1535 1536NamedDecl* 1537Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1538 QualType R, Decl* LastDeclarator, 1539 NamedDecl* PrevDecl, bool& InvalidDecl, 1540 bool &Redeclaration) { 1541 DeclarationName Name = GetNameForDeclarator(D); 1542 1543 // Check that there are no default arguments (C++ only). 1544 if (getLangOptions().CPlusPlus) 1545 CheckExtraCXXDefaultArguments(D); 1546 1547 if (R.getTypePtr()->isObjCInterfaceType()) { 1548 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object); 1549 InvalidDecl = true; 1550 } 1551 1552 VarDecl *NewVD; 1553 VarDecl::StorageClass SC; 1554 switch (D.getDeclSpec().getStorageClassSpec()) { 1555 default: assert(0 && "Unknown storage class!"); 1556 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1557 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1558 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1559 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1560 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1561 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1562 case DeclSpec::SCS_mutable: 1563 // mutable can only appear on non-static class members, so it's always 1564 // an error here 1565 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1566 InvalidDecl = true; 1567 SC = VarDecl::None; 1568 break; 1569 } 1570 1571 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1572 if (!II) { 1573 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1574 << Name.getAsString(); 1575 return 0; 1576 } 1577 1578 if (DC->isRecord()) { 1579 // This is a static data member for a C++ class. 1580 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1581 D.getIdentifierLoc(), II, 1582 R); 1583 } else { 1584 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1585 if (S->getFnParent() == 0) { 1586 // C99 6.9p2: The storage-class specifiers auto and register shall not 1587 // appear in the declaration specifiers in an external declaration. 1588 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1589 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1590 InvalidDecl = true; 1591 } 1592 } 1593 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1594 II, R, SC, 1595 // FIXME: Move to DeclGroup... 1596 D.getDeclSpec().getSourceRange().getBegin()); 1597 NewVD->setThreadSpecified(ThreadSpecified); 1598 } 1599 NewVD->setNextDeclarator(LastDeclarator); 1600 1601 // Handle attributes prior to checking for duplicates in MergeVarDecl 1602 ProcessDeclAttributes(NewVD, D); 1603 1604 // Handle GNU asm-label extension (encoded as an attribute). 1605 if (Expr *E = (Expr*) D.getAsmLabel()) { 1606 // The parser guarantees this is a string. 1607 StringLiteral *SE = cast<StringLiteral>(E); 1608 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1609 SE->getByteLength()))); 1610 } 1611 1612 // Emit an error if an address space was applied to decl with local storage. 1613 // This includes arrays of objects with address space qualifiers, but not 1614 // automatic variables that point to other address spaces. 1615 // ISO/IEC TR 18037 S5.1.2 1616 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1617 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1618 InvalidDecl = true; 1619 } 1620 1621 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1622 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1623 } 1624 1625 // If name lookup finds a previous declaration that is not in the 1626 // same scope as the new declaration, this may still be an 1627 // acceptable redeclaration. 1628 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1629 !(NewVD->hasLinkage() && 1630 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1631 PrevDecl = 0; 1632 1633 // Merge the decl with the existing one if appropriate. 1634 if (PrevDecl) { 1635 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1636 // The user tried to define a non-static data member 1637 // out-of-line (C++ [dcl.meaning]p1). 1638 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1639 << D.getCXXScopeSpec().getRange(); 1640 NewVD->Destroy(Context); 1641 return 0; 1642 } 1643 1644 Redeclaration = true; 1645 if (MergeVarDecl(NewVD, PrevDecl)) 1646 InvalidDecl = true; 1647 1648 if (D.getCXXScopeSpec().isSet()) { 1649 // No previous declaration in the qualifying scope. 1650 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1651 << Name << D.getCXXScopeSpec().getRange(); 1652 InvalidDecl = true; 1653 } 1654 } 1655 1656 // If this is a locally-scoped extern variable in C, inject a 1657 // declaration into translation unit scope so that all external 1658 // declarations are visible. 1659 if (!getLangOptions().CPlusPlus && CurContext->isFunctionOrMethod() && 1660 NewVD->hasLinkage()) 1661 InjectLocallyScopedExternalDeclaration(NewVD); 1662 1663 return NewVD; 1664} 1665 1666NamedDecl* 1667Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1668 QualType R, Decl *LastDeclarator, 1669 NamedDecl* PrevDecl, bool IsFunctionDefinition, 1670 bool& InvalidDecl, bool &Redeclaration) { 1671 assert(R.getTypePtr()->isFunctionType()); 1672 1673 DeclarationName Name = GetNameForDeclarator(D); 1674 FunctionDecl::StorageClass SC = FunctionDecl::None; 1675 switch (D.getDeclSpec().getStorageClassSpec()) { 1676 default: assert(0 && "Unknown storage class!"); 1677 case DeclSpec::SCS_auto: 1678 case DeclSpec::SCS_register: 1679 case DeclSpec::SCS_mutable: 1680 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1681 diag::err_typecheck_sclass_func); 1682 InvalidDecl = true; 1683 break; 1684 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1685 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1686 case DeclSpec::SCS_static: { 1687 if (DC->getLookupContext()->isFunctionOrMethod()) { 1688 // C99 6.7.1p5: 1689 // The declaration of an identifier for a function that has 1690 // block scope shall have no explicit storage-class specifier 1691 // other than extern 1692 // See also (C++ [dcl.stc]p4). 1693 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1694 diag::err_static_block_func); 1695 SC = FunctionDecl::None; 1696 } else 1697 SC = FunctionDecl::Static; 1698 break; 1699 } 1700 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1701 } 1702 1703 bool isInline = D.getDeclSpec().isInlineSpecified(); 1704 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1705 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1706 1707 FunctionDecl *NewFD; 1708 if (D.getKind() == Declarator::DK_Constructor) { 1709 // This is a C++ constructor declaration. 1710 assert(DC->isRecord() && 1711 "Constructors can only be declared in a member context"); 1712 1713 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1714 1715 // Create the new declaration 1716 NewFD = CXXConstructorDecl::Create(Context, 1717 cast<CXXRecordDecl>(DC), 1718 D.getIdentifierLoc(), Name, R, 1719 isExplicit, isInline, 1720 /*isImplicitlyDeclared=*/false); 1721 1722 if (InvalidDecl) 1723 NewFD->setInvalidDecl(); 1724 } else if (D.getKind() == Declarator::DK_Destructor) { 1725 // This is a C++ destructor declaration. 1726 if (DC->isRecord()) { 1727 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1728 1729 NewFD = CXXDestructorDecl::Create(Context, 1730 cast<CXXRecordDecl>(DC), 1731 D.getIdentifierLoc(), Name, R, 1732 isInline, 1733 /*isImplicitlyDeclared=*/false); 1734 1735 if (InvalidDecl) 1736 NewFD->setInvalidDecl(); 1737 } else { 1738 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1739 1740 // Create a FunctionDecl to satisfy the function definition parsing 1741 // code path. 1742 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1743 Name, R, SC, isInline, 1744 /*hasPrototype=*/true, 1745 // FIXME: Move to DeclGroup... 1746 D.getDeclSpec().getSourceRange().getBegin()); 1747 InvalidDecl = true; 1748 NewFD->setInvalidDecl(); 1749 } 1750 } else if (D.getKind() == Declarator::DK_Conversion) { 1751 if (!DC->isRecord()) { 1752 Diag(D.getIdentifierLoc(), 1753 diag::err_conv_function_not_member); 1754 return 0; 1755 } else { 1756 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1757 1758 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1759 D.getIdentifierLoc(), Name, R, 1760 isInline, isExplicit); 1761 1762 if (InvalidDecl) 1763 NewFD->setInvalidDecl(); 1764 } 1765 } else if (DC->isRecord()) { 1766 // This is a C++ method declaration. 1767 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1768 D.getIdentifierLoc(), Name, R, 1769 (SC == FunctionDecl::Static), isInline); 1770 } else { 1771 NewFD = FunctionDecl::Create(Context, DC, 1772 D.getIdentifierLoc(), 1773 Name, R, SC, isInline, 1774 /*hasPrototype=*/ 1775 (getLangOptions().CPlusPlus || 1776 (D.getNumTypeObjects() && 1777 D.getTypeObject(0).Fun.hasPrototype)), 1778 // FIXME: Move to DeclGroup... 1779 D.getDeclSpec().getSourceRange().getBegin()); 1780 } 1781 NewFD->setNextDeclarator(LastDeclarator); 1782 1783 // Set the lexical context. If the declarator has a C++ 1784 // scope specifier, the lexical context will be different 1785 // from the semantic context. 1786 NewFD->setLexicalDeclContext(CurContext); 1787 1788 // Handle GNU asm-label extension (encoded as an attribute). 1789 if (Expr *E = (Expr*) D.getAsmLabel()) { 1790 // The parser guarantees this is a string. 1791 StringLiteral *SE = cast<StringLiteral>(E); 1792 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1793 SE->getByteLength()))); 1794 } 1795 1796 // Copy the parameter declarations from the declarator D to 1797 // the function declaration NewFD, if they are available. 1798 if (D.getNumTypeObjects() > 0) { 1799 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1800 1801 // Create Decl objects for each parameter, adding them to the 1802 // FunctionDecl. 1803 llvm::SmallVector<ParmVarDecl*, 16> Params; 1804 1805 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1806 // function that takes no arguments, not a function that takes a 1807 // single void argument. 1808 // We let through "const void" here because Sema::GetTypeForDeclarator 1809 // already checks for that case. 1810 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1811 FTI.ArgInfo[0].Param && 1812 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1813 // empty arg list, don't push any params. 1814 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1815 1816 // In C++, the empty parameter-type-list must be spelled "void"; a 1817 // typedef of void is not permitted. 1818 if (getLangOptions().CPlusPlus && 1819 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1820 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1821 } 1822 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1823 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1824 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1825 } 1826 1827 NewFD->setParams(Context, &Params[0], Params.size()); 1828 } else if (R->getAsTypedefType()) { 1829 // When we're declaring a function with a typedef, as in the 1830 // following example, we'll need to synthesize (unnamed) 1831 // parameters for use in the declaration. 1832 // 1833 // @code 1834 // typedef void fn(int); 1835 // fn f; 1836 // @endcode 1837 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1838 if (!FT) { 1839 // This is a typedef of a function with no prototype, so we 1840 // don't need to do anything. 1841 } else if ((FT->getNumArgs() == 0) || 1842 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1843 FT->getArgType(0)->isVoidType())) { 1844 // This is a zero-argument function. We don't need to do anything. 1845 } else { 1846 // Synthesize a parameter for each argument type. 1847 llvm::SmallVector<ParmVarDecl*, 16> Params; 1848 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1849 ArgType != FT->arg_type_end(); ++ArgType) { 1850 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1851 SourceLocation(), 0, 1852 *ArgType, VarDecl::None, 1853 0); 1854 Param->setImplicit(); 1855 Params.push_back(Param); 1856 } 1857 1858 NewFD->setParams(Context, &Params[0], Params.size()); 1859 } 1860 } 1861 1862 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1863 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1864 else if (isa<CXXDestructorDecl>(NewFD)) { 1865 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1866 Record->setUserDeclaredDestructor(true); 1867 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1868 // user-defined destructor. 1869 Record->setPOD(false); 1870 } else if (CXXConversionDecl *Conversion = 1871 dyn_cast<CXXConversionDecl>(NewFD)) 1872 ActOnConversionDeclarator(Conversion); 1873 1874 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1875 if (NewFD->isOverloadedOperator() && 1876 CheckOverloadedOperatorDeclaration(NewFD)) 1877 NewFD->setInvalidDecl(); 1878 1879 // If name lookup finds a previous declaration that is not in the 1880 // same scope as the new declaration, this may still be an 1881 // acceptable redeclaration. 1882 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1883 !(NewFD->hasLinkage() && 1884 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1885 PrevDecl = 0; 1886 1887 // Merge or overload the declaration with an existing declaration of 1888 // the same name, if appropriate. 1889 bool OverloadableAttrRequired = false; 1890 if (PrevDecl) { 1891 // Determine whether NewFD is an overload of PrevDecl or 1892 // a declaration that requires merging. If it's an overload, 1893 // there's no more work to do here; we'll just add the new 1894 // function to the scope. 1895 OverloadedFunctionDecl::function_iterator MatchedDecl; 1896 1897 if (!getLangOptions().CPlusPlus && 1898 AllowOverloadingOfFunction(PrevDecl, Context)) { 1899 OverloadableAttrRequired = true; 1900 1901 // Functions marked "overloadable" must have a prototype (that 1902 // we can't get through declaration merging). 1903 if (!R->getAsFunctionTypeProto()) { 1904 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 1905 << NewFD; 1906 InvalidDecl = true; 1907 Redeclaration = true; 1908 1909 // Turn this into a variadic function with no parameters. 1910 R = Context.getFunctionType(R->getAsFunctionType()->getResultType(), 1911 0, 0, true, 0); 1912 NewFD->setType(R); 1913 } 1914 } 1915 1916 if (PrevDecl && 1917 (!AllowOverloadingOfFunction(PrevDecl, Context) || 1918 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 1919 Redeclaration = true; 1920 Decl *OldDecl = PrevDecl; 1921 1922 // If PrevDecl was an overloaded function, extract the 1923 // FunctionDecl that matched. 1924 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1925 OldDecl = *MatchedDecl; 1926 1927 // NewFD and PrevDecl represent declarations that need to be 1928 // merged. 1929 if (MergeFunctionDecl(NewFD, OldDecl)) 1930 InvalidDecl = true; 1931 1932 if (!InvalidDecl) { 1933 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1934 1935 // An out-of-line member function declaration must also be a 1936 // definition (C++ [dcl.meaning]p1). 1937 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1938 !InvalidDecl) { 1939 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1940 << D.getCXXScopeSpec().getRange(); 1941 NewFD->setInvalidDecl(); 1942 } 1943 } 1944 } 1945 } 1946 1947 if (D.getCXXScopeSpec().isSet() && 1948 (!PrevDecl || !Redeclaration)) { 1949 // The user tried to provide an out-of-line definition for a 1950 // function that is a member of a class or namespace, but there 1951 // was no such member function declared (C++ [class.mfct]p2, 1952 // C++ [namespace.memdef]p2). For example: 1953 // 1954 // class X { 1955 // void f() const; 1956 // }; 1957 // 1958 // void X::f() { } // ill-formed 1959 // 1960 // Complain about this problem, and attempt to suggest close 1961 // matches (e.g., those that differ only in cv-qualifiers and 1962 // whether the parameter types are references). 1963 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1964 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 1965 InvalidDecl = true; 1966 1967 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1968 true); 1969 assert(!Prev.isAmbiguous() && 1970 "Cannot have an ambiguity in previous-declaration lookup"); 1971 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1972 Func != FuncEnd; ++Func) { 1973 if (isa<FunctionDecl>(*Func) && 1974 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 1975 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1976 } 1977 1978 PrevDecl = 0; 1979 } 1980 1981 // Handle attributes. We need to have merged decls when handling attributes 1982 // (for example to check for conflicts, etc). 1983 ProcessDeclAttributes(NewFD, D); 1984 AddKnownFunctionAttributes(NewFD); 1985 1986 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 1987 // If a function name is overloadable in C, then every function 1988 // with that name must be marked "overloadable". 1989 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 1990 << Redeclaration << NewFD; 1991 if (PrevDecl) 1992 Diag(PrevDecl->getLocation(), 1993 diag::note_attribute_overloadable_prev_overload); 1994 NewFD->addAttr(new OverloadableAttr); 1995 } 1996 1997 if (getLangOptions().CPlusPlus) { 1998 // In C++, check default arguments now that we have merged decls. Unless 1999 // the lexical context is the class, because in this case this is done 2000 // during delayed parsing anyway. 2001 if (!CurContext->isRecord()) 2002 CheckCXXDefaultArguments(NewFD); 2003 2004 // An out-of-line member function declaration must also be a 2005 // definition (C++ [dcl.meaning]p1). 2006 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2007 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2008 << D.getCXXScopeSpec().getRange(); 2009 InvalidDecl = true; 2010 } 2011 } 2012 2013 // If this is a locally-scoped function in C, inject a declaration 2014 // into translation unit scope so that all external declarations are 2015 // visible. 2016 if (!getLangOptions().CPlusPlus && CurContext->isFunctionOrMethod()) 2017 InjectLocallyScopedExternalDeclaration(NewFD); 2018 2019 return NewFD; 2020} 2021 2022void Sema::InitializerElementNotConstant(const Expr *Init) { 2023 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2024 << Init->getSourceRange(); 2025} 2026 2027bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 2028 switch (Init->getStmtClass()) { 2029 default: 2030 InitializerElementNotConstant(Init); 2031 return true; 2032 case Expr::ParenExprClass: { 2033 const ParenExpr* PE = cast<ParenExpr>(Init); 2034 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 2035 } 2036 case Expr::CompoundLiteralExprClass: 2037 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 2038 case Expr::DeclRefExprClass: 2039 case Expr::QualifiedDeclRefExprClass: { 2040 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2041 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 2042 if (VD->hasGlobalStorage()) 2043 return false; 2044 InitializerElementNotConstant(Init); 2045 return true; 2046 } 2047 if (isa<FunctionDecl>(D)) 2048 return false; 2049 InitializerElementNotConstant(Init); 2050 return true; 2051 } 2052 case Expr::MemberExprClass: { 2053 const MemberExpr *M = cast<MemberExpr>(Init); 2054 if (M->isArrow()) 2055 return CheckAddressConstantExpression(M->getBase()); 2056 return CheckAddressConstantExpressionLValue(M->getBase()); 2057 } 2058 case Expr::ArraySubscriptExprClass: { 2059 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 2060 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 2061 return CheckAddressConstantExpression(ASE->getBase()) || 2062 CheckArithmeticConstantExpression(ASE->getIdx()); 2063 } 2064 case Expr::StringLiteralClass: 2065 case Expr::ObjCEncodeExprClass: 2066 case Expr::PredefinedExprClass: 2067 return false; 2068 case Expr::UnaryOperatorClass: { 2069 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2070 2071 // C99 6.6p9 2072 if (Exp->getOpcode() == UnaryOperator::Deref) 2073 return CheckAddressConstantExpression(Exp->getSubExpr()); 2074 2075 InitializerElementNotConstant(Init); 2076 return true; 2077 } 2078 } 2079} 2080 2081bool Sema::CheckAddressConstantExpression(const Expr* Init) { 2082 switch (Init->getStmtClass()) { 2083 default: 2084 InitializerElementNotConstant(Init); 2085 return true; 2086 case Expr::ParenExprClass: 2087 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 2088 case Expr::StringLiteralClass: 2089 case Expr::ObjCEncodeExprClass: 2090 case Expr::ObjCStringLiteralClass: 2091 return false; 2092 case Expr::CallExprClass: 2093 case Expr::CXXOperatorCallExprClass: 2094 // __builtin___CFStringMakeConstantString is a valid constant l-value. 2095 if (cast<CallExpr>(Init)->isBuiltinCall(Context) == 2096 Builtin::BI__builtin___CFStringMakeConstantString) 2097 return false; 2098 2099 InitializerElementNotConstant(Init); 2100 return true; 2101 2102 case Expr::UnaryOperatorClass: { 2103 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2104 2105 // C99 6.6p9 2106 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2107 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 2108 2109 if (Exp->getOpcode() == UnaryOperator::Extension) 2110 return CheckAddressConstantExpression(Exp->getSubExpr()); 2111 2112 InitializerElementNotConstant(Init); 2113 return true; 2114 } 2115 case Expr::BinaryOperatorClass: { 2116 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 2117 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2118 2119 Expr *PExp = Exp->getLHS(); 2120 Expr *IExp = Exp->getRHS(); 2121 if (IExp->getType()->isPointerType()) 2122 std::swap(PExp, IExp); 2123 2124 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 2125 return CheckAddressConstantExpression(PExp) || 2126 CheckArithmeticConstantExpression(IExp); 2127 } 2128 case Expr::ImplicitCastExprClass: 2129 case Expr::CStyleCastExprClass: { 2130 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2131 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 2132 // Check for implicit promotion 2133 if (SubExpr->getType()->isFunctionType() || 2134 SubExpr->getType()->isArrayType()) 2135 return CheckAddressConstantExpressionLValue(SubExpr); 2136 } 2137 2138 // Check for pointer->pointer cast 2139 if (SubExpr->getType()->isPointerType()) 2140 return CheckAddressConstantExpression(SubExpr); 2141 2142 if (SubExpr->getType()->isIntegralType()) { 2143 // Check for the special-case of a pointer->int->pointer cast; 2144 // this isn't standard, but some code requires it. See 2145 // PR2720 for an example. 2146 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 2147 if (SubCast->getSubExpr()->getType()->isPointerType()) { 2148 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 2149 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2150 if (IntWidth >= PointerWidth) { 2151 return CheckAddressConstantExpression(SubCast->getSubExpr()); 2152 } 2153 } 2154 } 2155 } 2156 if (SubExpr->getType()->isArithmeticType()) { 2157 return CheckArithmeticConstantExpression(SubExpr); 2158 } 2159 2160 InitializerElementNotConstant(Init); 2161 return true; 2162 } 2163 case Expr::ConditionalOperatorClass: { 2164 // FIXME: Should we pedwarn here? 2165 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2166 if (!Exp->getCond()->getType()->isArithmeticType()) { 2167 InitializerElementNotConstant(Init); 2168 return true; 2169 } 2170 if (CheckArithmeticConstantExpression(Exp->getCond())) 2171 return true; 2172 if (Exp->getLHS() && 2173 CheckAddressConstantExpression(Exp->getLHS())) 2174 return true; 2175 return CheckAddressConstantExpression(Exp->getRHS()); 2176 } 2177 case Expr::AddrLabelExprClass: 2178 return false; 2179 } 2180} 2181 2182static const Expr* FindExpressionBaseAddress(const Expr* E); 2183 2184static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 2185 switch (E->getStmtClass()) { 2186 default: 2187 return E; 2188 case Expr::ParenExprClass: { 2189 const ParenExpr* PE = cast<ParenExpr>(E); 2190 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 2191 } 2192 case Expr::MemberExprClass: { 2193 const MemberExpr *M = cast<MemberExpr>(E); 2194 if (M->isArrow()) 2195 return FindExpressionBaseAddress(M->getBase()); 2196 return FindExpressionBaseAddressLValue(M->getBase()); 2197 } 2198 case Expr::ArraySubscriptExprClass: { 2199 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 2200 return FindExpressionBaseAddress(ASE->getBase()); 2201 } 2202 case Expr::UnaryOperatorClass: { 2203 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2204 2205 if (Exp->getOpcode() == UnaryOperator::Deref) 2206 return FindExpressionBaseAddress(Exp->getSubExpr()); 2207 2208 return E; 2209 } 2210 } 2211} 2212 2213static const Expr* FindExpressionBaseAddress(const Expr* E) { 2214 switch (E->getStmtClass()) { 2215 default: 2216 return E; 2217 case Expr::ParenExprClass: { 2218 const ParenExpr* PE = cast<ParenExpr>(E); 2219 return FindExpressionBaseAddress(PE->getSubExpr()); 2220 } 2221 case Expr::UnaryOperatorClass: { 2222 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2223 2224 // C99 6.6p9 2225 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2226 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 2227 2228 if (Exp->getOpcode() == UnaryOperator::Extension) 2229 return FindExpressionBaseAddress(Exp->getSubExpr()); 2230 2231 return E; 2232 } 2233 case Expr::BinaryOperatorClass: { 2234 const BinaryOperator *Exp = cast<BinaryOperator>(E); 2235 2236 Expr *PExp = Exp->getLHS(); 2237 Expr *IExp = Exp->getRHS(); 2238 if (IExp->getType()->isPointerType()) 2239 std::swap(PExp, IExp); 2240 2241 return FindExpressionBaseAddress(PExp); 2242 } 2243 case Expr::ImplicitCastExprClass: { 2244 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2245 2246 // Check for implicit promotion 2247 if (SubExpr->getType()->isFunctionType() || 2248 SubExpr->getType()->isArrayType()) 2249 return FindExpressionBaseAddressLValue(SubExpr); 2250 2251 // Check for pointer->pointer cast 2252 if (SubExpr->getType()->isPointerType()) 2253 return FindExpressionBaseAddress(SubExpr); 2254 2255 // We assume that we have an arithmetic expression here; 2256 // if we don't, we'll figure it out later 2257 return 0; 2258 } 2259 case Expr::CStyleCastExprClass: { 2260 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2261 2262 // Check for pointer->pointer cast 2263 if (SubExpr->getType()->isPointerType()) 2264 return FindExpressionBaseAddress(SubExpr); 2265 2266 // We assume that we have an arithmetic expression here; 2267 // if we don't, we'll figure it out later 2268 return 0; 2269 } 2270 } 2271} 2272 2273bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2274 switch (Init->getStmtClass()) { 2275 default: 2276 InitializerElementNotConstant(Init); 2277 return true; 2278 case Expr::ParenExprClass: { 2279 const ParenExpr* PE = cast<ParenExpr>(Init); 2280 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2281 } 2282 case Expr::FloatingLiteralClass: 2283 case Expr::IntegerLiteralClass: 2284 case Expr::CharacterLiteralClass: 2285 case Expr::ImaginaryLiteralClass: 2286 case Expr::TypesCompatibleExprClass: 2287 case Expr::CXXBoolLiteralExprClass: 2288 return false; 2289 case Expr::CallExprClass: 2290 case Expr::CXXOperatorCallExprClass: { 2291 const CallExpr *CE = cast<CallExpr>(Init); 2292 2293 // Allow any constant foldable calls to builtins. 2294 if (CE->isBuiltinCall(Context) && CE->isEvaluatable(Context)) 2295 return false; 2296 2297 InitializerElementNotConstant(Init); 2298 return true; 2299 } 2300 case Expr::DeclRefExprClass: 2301 case Expr::QualifiedDeclRefExprClass: { 2302 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2303 if (isa<EnumConstantDecl>(D)) 2304 return false; 2305 InitializerElementNotConstant(Init); 2306 return true; 2307 } 2308 case Expr::CompoundLiteralExprClass: 2309 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2310 // but vectors are allowed to be magic. 2311 if (Init->getType()->isVectorType()) 2312 return false; 2313 InitializerElementNotConstant(Init); 2314 return true; 2315 case Expr::UnaryOperatorClass: { 2316 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2317 2318 switch (Exp->getOpcode()) { 2319 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2320 // See C99 6.6p3. 2321 default: 2322 InitializerElementNotConstant(Init); 2323 return true; 2324 case UnaryOperator::OffsetOf: 2325 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2326 return false; 2327 InitializerElementNotConstant(Init); 2328 return true; 2329 case UnaryOperator::Extension: 2330 case UnaryOperator::LNot: 2331 case UnaryOperator::Plus: 2332 case UnaryOperator::Minus: 2333 case UnaryOperator::Not: 2334 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2335 } 2336 } 2337 case Expr::SizeOfAlignOfExprClass: { 2338 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2339 // Special check for void types, which are allowed as an extension 2340 if (Exp->getTypeOfArgument()->isVoidType()) 2341 return false; 2342 // alignof always evaluates to a constant. 2343 // FIXME: is sizeof(int[3.0]) a constant expression? 2344 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2345 InitializerElementNotConstant(Init); 2346 return true; 2347 } 2348 return false; 2349 } 2350 case Expr::BinaryOperatorClass: { 2351 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2352 2353 if (Exp->getLHS()->getType()->isArithmeticType() && 2354 Exp->getRHS()->getType()->isArithmeticType()) { 2355 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2356 CheckArithmeticConstantExpression(Exp->getRHS()); 2357 } 2358 2359 if (Exp->getLHS()->getType()->isPointerType() && 2360 Exp->getRHS()->getType()->isPointerType()) { 2361 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2362 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2363 2364 // Only allow a null (constant integer) base; we could 2365 // allow some additional cases if necessary, but this 2366 // is sufficient to cover offsetof-like constructs. 2367 if (!LHSBase && !RHSBase) { 2368 return CheckAddressConstantExpression(Exp->getLHS()) || 2369 CheckAddressConstantExpression(Exp->getRHS()); 2370 } 2371 } 2372 2373 InitializerElementNotConstant(Init); 2374 return true; 2375 } 2376 case Expr::ImplicitCastExprClass: 2377 case Expr::CStyleCastExprClass: { 2378 const CastExpr *CE = cast<CastExpr>(Init); 2379 const Expr *SubExpr = CE->getSubExpr(); 2380 2381 if (SubExpr->getType()->isArithmeticType()) 2382 return CheckArithmeticConstantExpression(SubExpr); 2383 2384 if (SubExpr->getType()->isPointerType()) { 2385 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2386 if (Base) { 2387 // the cast is only valid if done to a wide enough type 2388 if (Context.getTypeSize(CE->getType()) >= 2389 Context.getTypeSize(SubExpr->getType())) 2390 return false; 2391 } else { 2392 // If the pointer has a null base, this is an offsetof-like construct 2393 return CheckAddressConstantExpression(SubExpr); 2394 } 2395 } 2396 2397 InitializerElementNotConstant(Init); 2398 return true; 2399 } 2400 case Expr::ConditionalOperatorClass: { 2401 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2402 2403 // If GNU extensions are disabled, we require all operands to be arithmetic 2404 // constant expressions. 2405 if (getLangOptions().NoExtensions) { 2406 return CheckArithmeticConstantExpression(Exp->getCond()) || 2407 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2408 CheckArithmeticConstantExpression(Exp->getRHS()); 2409 } 2410 2411 // Otherwise, we have to emulate some of the behavior of fold here. 2412 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2413 // because it can constant fold things away. To retain compatibility with 2414 // GCC code, we see if we can fold the condition to a constant (which we 2415 // should always be able to do in theory). If so, we only require the 2416 // specified arm of the conditional to be a constant. This is a horrible 2417 // hack, but is require by real world code that uses __builtin_constant_p. 2418 Expr::EvalResult EvalResult; 2419 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2420 EvalResult.HasSideEffects) { 2421 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2422 // won't be able to either. Use it to emit the diagnostic though. 2423 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2424 assert(Res && "Evaluate couldn't evaluate this constant?"); 2425 return Res; 2426 } 2427 2428 // Verify that the side following the condition is also a constant. 2429 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2430 if (EvalResult.Val.getInt() == 0) 2431 std::swap(TrueSide, FalseSide); 2432 2433 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2434 return true; 2435 2436 // Okay, the evaluated side evaluates to a constant, so we accept this. 2437 // Check to see if the other side is obviously not a constant. If so, 2438 // emit a warning that this is a GNU extension. 2439 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2440 Diag(Init->getExprLoc(), 2441 diag::ext_typecheck_expression_not_constant_but_accepted) 2442 << FalseSide->getSourceRange(); 2443 return false; 2444 } 2445 } 2446} 2447 2448bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2449 if (Init->isConstantInitializer(Context)) 2450 return false; 2451 InitializerElementNotConstant(Init); 2452 return true; 2453 2454 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2455 Init = DIE->getInit(); 2456 2457 Init = Init->IgnoreParens(); 2458 2459 if (Init->isEvaluatable(Context)) 2460 return false; 2461 2462 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2463 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2464 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2465 2466 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2467 return CheckForConstantInitializer(e->getInitializer(), DclT); 2468 2469 if (isa<ImplicitValueInitExpr>(Init)) { 2470 // FIXME: In C++, check for non-POD types. 2471 return false; 2472 } 2473 2474 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2475 unsigned numInits = Exp->getNumInits(); 2476 for (unsigned i = 0; i < numInits; i++) { 2477 // FIXME: Need to get the type of the declaration for C++, 2478 // because it could be a reference? 2479 2480 if (CheckForConstantInitializer(Exp->getInit(i), 2481 Exp->getInit(i)->getType())) 2482 return true; 2483 } 2484 return false; 2485 } 2486 2487 // FIXME: We can probably remove some of this code below, now that 2488 // Expr::Evaluate is doing the heavy lifting for scalars. 2489 2490 if (Init->isNullPointerConstant(Context)) 2491 return false; 2492 if (Init->getType()->isArithmeticType()) { 2493 QualType InitTy = Context.getCanonicalType(Init->getType()) 2494 .getUnqualifiedType(); 2495 if (InitTy == Context.BoolTy) { 2496 // Special handling for pointers implicitly cast to bool; 2497 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2498 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2499 Expr* SubE = ICE->getSubExpr(); 2500 if (SubE->getType()->isPointerType() || 2501 SubE->getType()->isArrayType() || 2502 SubE->getType()->isFunctionType()) { 2503 return CheckAddressConstantExpression(Init); 2504 } 2505 } 2506 } else if (InitTy->isIntegralType()) { 2507 Expr* SubE = 0; 2508 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2509 SubE = CE->getSubExpr(); 2510 // Special check for pointer cast to int; we allow as an extension 2511 // an address constant cast to an integer if the integer 2512 // is of an appropriate width (this sort of code is apparently used 2513 // in some places). 2514 // FIXME: Add pedwarn? 2515 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2516 if (SubE && (SubE->getType()->isPointerType() || 2517 SubE->getType()->isArrayType() || 2518 SubE->getType()->isFunctionType())) { 2519 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2520 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2521 if (IntWidth >= PointerWidth) 2522 return CheckAddressConstantExpression(Init); 2523 } 2524 } 2525 2526 return CheckArithmeticConstantExpression(Init); 2527 } 2528 2529 if (Init->getType()->isPointerType()) 2530 return CheckAddressConstantExpression(Init); 2531 2532 // An array type at the top level that isn't an init-list must 2533 // be a string literal 2534 if (Init->getType()->isArrayType()) 2535 return false; 2536 2537 if (Init->getType()->isFunctionType()) 2538 return false; 2539 2540 // Allow block exprs at top level. 2541 if (Init->getType()->isBlockPointerType()) 2542 return false; 2543 2544 // GCC cast to union extension 2545 // note: the validity of the cast expr is checked by CheckCastTypes() 2546 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2547 QualType T = C->getType(); 2548 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2549 } 2550 2551 InitializerElementNotConstant(Init); 2552 return true; 2553} 2554 2555void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2556 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2557} 2558 2559/// AddInitializerToDecl - Adds the initializer Init to the 2560/// declaration dcl. If DirectInit is true, this is C++ direct 2561/// initialization rather than copy initialization. 2562void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2563 Decl *RealDecl = static_cast<Decl *>(dcl); 2564 Expr *Init = static_cast<Expr *>(init.release()); 2565 assert(Init && "missing initializer"); 2566 2567 // If there is no declaration, there was an error parsing it. Just ignore 2568 // the initializer. 2569 if (RealDecl == 0) { 2570 Init->Destroy(Context); 2571 return; 2572 } 2573 2574 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2575 if (!VDecl) { 2576 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2577 RealDecl->setInvalidDecl(); 2578 return; 2579 } 2580 // Get the decls type and save a reference for later, since 2581 // CheckInitializerTypes may change it. 2582 QualType DclT = VDecl->getType(), SavT = DclT; 2583 if (VDecl->isBlockVarDecl()) { 2584 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2585 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2586 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2587 VDecl->setInvalidDecl(); 2588 } else if (!VDecl->isInvalidDecl()) { 2589 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2590 VDecl->getDeclName(), DirectInit)) 2591 VDecl->setInvalidDecl(); 2592 2593 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2594 // Don't check invalid declarations to avoid emitting useless diagnostics. 2595 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2596 if (SC == VarDecl::Static) // C99 6.7.8p4. 2597 CheckForConstantInitializer(Init, DclT); 2598 } 2599 } 2600 } else if (VDecl->isFileVarDecl()) { 2601 if (VDecl->getStorageClass() == VarDecl::Extern) 2602 Diag(VDecl->getLocation(), diag::warn_extern_init); 2603 if (!VDecl->isInvalidDecl()) 2604 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2605 VDecl->getDeclName(), DirectInit)) 2606 VDecl->setInvalidDecl(); 2607 2608 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2609 // Don't check invalid declarations to avoid emitting useless diagnostics. 2610 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2611 // C99 6.7.8p4. All file scoped initializers need to be constant. 2612 CheckForConstantInitializer(Init, DclT); 2613 } 2614 } 2615 // If the type changed, it means we had an incomplete type that was 2616 // completed by the initializer. For example: 2617 // int ary[] = { 1, 3, 5 }; 2618 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2619 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2620 VDecl->setType(DclT); 2621 Init->setType(DclT); 2622 } 2623 2624 // Attach the initializer to the decl. 2625 VDecl->setInit(Init); 2626 return; 2627} 2628 2629void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2630 Decl *RealDecl = static_cast<Decl *>(dcl); 2631 2632 // If there is no declaration, there was an error parsing it. Just ignore it. 2633 if (RealDecl == 0) 2634 return; 2635 2636 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2637 QualType Type = Var->getType(); 2638 // C++ [dcl.init.ref]p3: 2639 // The initializer can be omitted for a reference only in a 2640 // parameter declaration (8.3.5), in the declaration of a 2641 // function return type, in the declaration of a class member 2642 // within its class declaration (9.2), and where the extern 2643 // specifier is explicitly used. 2644 if (Type->isReferenceType() && 2645 Var->getStorageClass() != VarDecl::Extern && 2646 Var->getStorageClass() != VarDecl::PrivateExtern) { 2647 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2648 << Var->getDeclName() 2649 << SourceRange(Var->getLocation(), Var->getLocation()); 2650 Var->setInvalidDecl(); 2651 return; 2652 } 2653 2654 // C++ [dcl.init]p9: 2655 // 2656 // If no initializer is specified for an object, and the object 2657 // is of (possibly cv-qualified) non-POD class type (or array 2658 // thereof), the object shall be default-initialized; if the 2659 // object is of const-qualified type, the underlying class type 2660 // shall have a user-declared default constructor. 2661 if (getLangOptions().CPlusPlus) { 2662 QualType InitType = Type; 2663 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2664 InitType = Array->getElementType(); 2665 if (Var->getStorageClass() != VarDecl::Extern && 2666 Var->getStorageClass() != VarDecl::PrivateExtern && 2667 InitType->isRecordType()) { 2668 const CXXConstructorDecl *Constructor 2669 = PerformInitializationByConstructor(InitType, 0, 0, 2670 Var->getLocation(), 2671 SourceRange(Var->getLocation(), 2672 Var->getLocation()), 2673 Var->getDeclName(), 2674 IK_Default); 2675 if (!Constructor) 2676 Var->setInvalidDecl(); 2677 } 2678 } 2679 2680#if 0 2681 // FIXME: Temporarily disabled because we are not properly parsing 2682 // linkage specifications on declarations, e.g., 2683 // 2684 // extern "C" const CGPoint CGPointerZero; 2685 // 2686 // C++ [dcl.init]p9: 2687 // 2688 // If no initializer is specified for an object, and the 2689 // object is of (possibly cv-qualified) non-POD class type (or 2690 // array thereof), the object shall be default-initialized; if 2691 // the object is of const-qualified type, the underlying class 2692 // type shall have a user-declared default 2693 // constructor. Otherwise, if no initializer is specified for 2694 // an object, the object and its subobjects, if any, have an 2695 // indeterminate initial value; if the object or any of its 2696 // subobjects are of const-qualified type, the program is 2697 // ill-formed. 2698 // 2699 // This isn't technically an error in C, so we don't diagnose it. 2700 // 2701 // FIXME: Actually perform the POD/user-defined default 2702 // constructor check. 2703 if (getLangOptions().CPlusPlus && 2704 Context.getCanonicalType(Type).isConstQualified() && 2705 Var->getStorageClass() != VarDecl::Extern) 2706 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2707 << Var->getName() 2708 << SourceRange(Var->getLocation(), Var->getLocation()); 2709#endif 2710 } 2711} 2712 2713/// The declarators are chained together backwards, reverse the list. 2714Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2715 // Often we have single declarators, handle them quickly. 2716 Decl *Group = static_cast<Decl*>(group); 2717 if (Group == 0) 2718 return 0; 2719 2720 Decl *NewGroup = 0; 2721 if (Group->getNextDeclarator() == 0) 2722 NewGroup = Group; 2723 else { // reverse the list. 2724 while (Group) { 2725 Decl *Next = Group->getNextDeclarator(); 2726 Group->setNextDeclarator(NewGroup); 2727 NewGroup = Group; 2728 Group = Next; 2729 } 2730 } 2731 // Perform semantic analysis that depends on having fully processed both 2732 // the declarator and initializer. 2733 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2734 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2735 if (!IDecl) 2736 continue; 2737 QualType T = IDecl->getType(); 2738 2739 bool isIllegalVLA = T->isVariableArrayType() && IDecl->hasGlobalStorage(); 2740 bool isIllegalVM = T->isVariablyModifiedType() && IDecl->hasLinkage(); 2741 if (isIllegalVLA || isIllegalVM) { 2742 bool SizeIsNegative; 2743 QualType FixedTy = 2744 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2745 if (!FixedTy.isNull()) { 2746 Diag(IDecl->getLocation(), diag::warn_illegal_constant_array_size); 2747 IDecl->setType(FixedTy); 2748 } else if (T->isVariableArrayType()) { 2749 IDecl->setInvalidDecl(); 2750 2751 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2752 // FIXME: This won't give the correct result for 2753 // int a[10][n]; 2754 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2755 2756 if (IDecl->isFileVarDecl()) 2757 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) 2758 << SizeRange; 2759 else if (IDecl->getStorageClass() == VarDecl::Static) 2760 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2761 << SizeRange; 2762 else 2763 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2764 << SizeRange; 2765 } else { 2766 IDecl->setInvalidDecl(); 2767 2768 if (IDecl->isFileVarDecl()) 2769 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2770 else 2771 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2772 } 2773 } 2774 2775 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2776 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2777 if (IDecl->isBlockVarDecl() && 2778 IDecl->getStorageClass() != VarDecl::Extern) { 2779 if (!IDecl->isInvalidDecl() && 2780 DiagnoseIncompleteType(IDecl->getLocation(), T, 2781 diag::err_typecheck_decl_incomplete_type)) 2782 IDecl->setInvalidDecl(); 2783 } 2784 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2785 // object that has file scope without an initializer, and without a 2786 // storage-class specifier or with the storage-class specifier "static", 2787 // constitutes a tentative definition. Note: A tentative definition with 2788 // external linkage is valid (C99 6.2.2p5). 2789 if (isTentativeDefinition(IDecl)) { 2790 if (T->isIncompleteArrayType()) { 2791 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2792 // array to be completed. Don't issue a diagnostic. 2793 } else if (!IDecl->isInvalidDecl() && 2794 DiagnoseIncompleteType(IDecl->getLocation(), T, 2795 diag::err_typecheck_decl_incomplete_type)) 2796 // C99 6.9.2p3: If the declaration of an identifier for an object is 2797 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2798 // declared type shall not be an incomplete type. 2799 IDecl->setInvalidDecl(); 2800 } 2801 if (IDecl->isFileVarDecl()) 2802 CheckForFileScopedRedefinitions(S, IDecl); 2803 } 2804 return NewGroup; 2805} 2806 2807/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2808/// to introduce parameters into function prototype scope. 2809Sema::DeclTy * 2810Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2811 const DeclSpec &DS = D.getDeclSpec(); 2812 2813 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2814 VarDecl::StorageClass StorageClass = VarDecl::None; 2815 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2816 StorageClass = VarDecl::Register; 2817 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2818 Diag(DS.getStorageClassSpecLoc(), 2819 diag::err_invalid_storage_class_in_func_decl); 2820 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2821 } 2822 if (DS.isThreadSpecified()) { 2823 Diag(DS.getThreadSpecLoc(), 2824 diag::err_invalid_storage_class_in_func_decl); 2825 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2826 } 2827 2828 // Check that there are no default arguments inside the type of this 2829 // parameter (C++ only). 2830 if (getLangOptions().CPlusPlus) 2831 CheckExtraCXXDefaultArguments(D); 2832 2833 // In this context, we *do not* check D.getInvalidType(). If the declarator 2834 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2835 // though it will not reflect the user specified type. 2836 QualType parmDeclType = GetTypeForDeclarator(D, S); 2837 2838 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2839 2840 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2841 // Can this happen for params? We already checked that they don't conflict 2842 // among each other. Here they can only shadow globals, which is ok. 2843 IdentifierInfo *II = D.getIdentifier(); 2844 if (II) { 2845 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2846 if (PrevDecl->isTemplateParameter()) { 2847 // Maybe we will complain about the shadowed template parameter. 2848 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2849 // Just pretend that we didn't see the previous declaration. 2850 PrevDecl = 0; 2851 } else if (S->isDeclScope(PrevDecl)) { 2852 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2853 2854 // Recover by removing the name 2855 II = 0; 2856 D.SetIdentifier(0, D.getIdentifierLoc()); 2857 } 2858 } 2859 } 2860 2861 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2862 // Doing the promotion here has a win and a loss. The win is the type for 2863 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2864 // code generator). The loss is the orginal type isn't preserved. For example: 2865 // 2866 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2867 // int blockvardecl[5]; 2868 // sizeof(parmvardecl); // size == 4 2869 // sizeof(blockvardecl); // size == 20 2870 // } 2871 // 2872 // For expressions, all implicit conversions are captured using the 2873 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2874 // 2875 // FIXME: If a source translation tool needs to see the original type, then 2876 // we need to consider storing both types (in ParmVarDecl)... 2877 // 2878 if (parmDeclType->isArrayType()) { 2879 // int x[restrict 4] -> int *restrict 2880 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2881 } else if (parmDeclType->isFunctionType()) 2882 parmDeclType = Context.getPointerType(parmDeclType); 2883 2884 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2885 D.getIdentifierLoc(), II, 2886 parmDeclType, StorageClass, 2887 0); 2888 2889 if (D.getInvalidType()) 2890 New->setInvalidDecl(); 2891 2892 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2893 if (D.getCXXScopeSpec().isSet()) { 2894 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2895 << D.getCXXScopeSpec().getRange(); 2896 New->setInvalidDecl(); 2897 } 2898 // Parameter declarators cannot be interface types. All ObjC objects are 2899 // passed by reference. 2900 if (parmDeclType->isObjCInterfaceType()) { 2901 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2902 << "passed"; 2903 New->setInvalidDecl(); 2904 } 2905 2906 // Add the parameter declaration into this scope. 2907 S->AddDecl(New); 2908 if (II) 2909 IdResolver.AddDecl(New); 2910 2911 ProcessDeclAttributes(New, D); 2912 return New; 2913 2914} 2915 2916void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2917 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2918 "Not a function declarator!"); 2919 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2920 2921 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2922 // for a K&R function. 2923 if (!FTI.hasPrototype) { 2924 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2925 if (FTI.ArgInfo[i].Param == 0) { 2926 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2927 << FTI.ArgInfo[i].Ident; 2928 // Implicitly declare the argument as type 'int' for lack of a better 2929 // type. 2930 DeclSpec DS; 2931 const char* PrevSpec; // unused 2932 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2933 PrevSpec); 2934 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2935 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2936 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2937 } 2938 } 2939 } 2940} 2941 2942Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2943 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2944 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2945 "Not a function declarator!"); 2946 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2947 2948 if (FTI.hasPrototype) { 2949 // FIXME: Diagnose arguments without names in C. 2950 } 2951 2952 Scope *ParentScope = FnBodyScope->getParent(); 2953 2954 return ActOnStartOfFunctionDef(FnBodyScope, 2955 ActOnDeclarator(ParentScope, D, 0, 2956 /*IsFunctionDefinition=*/true)); 2957} 2958 2959Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2960 Decl *decl = static_cast<Decl*>(D); 2961 FunctionDecl *FD = cast<FunctionDecl>(decl); 2962 2963 // See if this is a redefinition. 2964 const FunctionDecl *Definition; 2965 if (FD->getBody(Definition)) { 2966 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2967 Diag(Definition->getLocation(), diag::note_previous_definition); 2968 } 2969 2970 // Builtin functions cannot be defined. 2971 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2972 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2973 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2974 FD->setInvalidDecl(); 2975 } 2976 } 2977 2978 PushDeclContext(FnBodyScope, FD); 2979 2980 // Check the validity of our function parameters 2981 CheckParmsForFunctionDef(FD); 2982 2983 // Introduce our parameters into the function scope 2984 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2985 ParmVarDecl *Param = FD->getParamDecl(p); 2986 Param->setOwningFunction(FD); 2987 2988 // If this has an identifier, add it to the scope stack. 2989 if (Param->getIdentifier()) 2990 PushOnScopeChains(Param, FnBodyScope); 2991 } 2992 2993 // Checking attributes of current function definition 2994 // dllimport attribute. 2995 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2996 // dllimport attribute cannot be applied to definition. 2997 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2998 Diag(FD->getLocation(), 2999 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3000 << "dllimport"; 3001 FD->setInvalidDecl(); 3002 return FD; 3003 } else { 3004 // If a symbol previously declared dllimport is later defined, the 3005 // attribute is ignored in subsequent references, and a warning is 3006 // emitted. 3007 Diag(FD->getLocation(), 3008 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3009 << FD->getNameAsCString() << "dllimport"; 3010 } 3011 } 3012 return FD; 3013} 3014 3015Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 3016 Decl *dcl = static_cast<Decl *>(D); 3017 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 3018 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3019 FD->setBody(Body); 3020 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3021 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3022 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3023 MD->setBody((Stmt*)Body); 3024 } else { 3025 Body->Destroy(Context); 3026 return 0; 3027 } 3028 PopDeclContext(); 3029 // Verify and clean out per-function state. 3030 3031 // Check goto/label use. 3032 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3033 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 3034 // Verify that we have no forward references left. If so, there was a goto 3035 // or address of a label taken, but no definition of it. Label fwd 3036 // definitions are indicated with a null substmt. 3037 if (I->second->getSubStmt() == 0) { 3038 LabelStmt *L = I->second; 3039 // Emit error. 3040 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3041 3042 // At this point, we have gotos that use the bogus label. Stitch it into 3043 // the function body so that they aren't leaked and that the AST is well 3044 // formed. 3045 if (Body) { 3046#if 0 3047 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 3048 // and the AST is malformed anyway. We should just blow away 'L'. 3049 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3050 cast<CompoundStmt>(Body)->push_back(L); 3051#else 3052 L->Destroy(Context); 3053#endif 3054 } else { 3055 // The whole function wasn't parsed correctly, just delete this. 3056 L->Destroy(Context); 3057 } 3058 } 3059 } 3060 LabelMap.clear(); 3061 3062 return D; 3063} 3064 3065/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3066/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3067NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3068 IdentifierInfo &II, Scope *S) { 3069 // Extension in C99. Legal in C90, but warn about it. 3070 if (getLangOptions().C99) 3071 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3072 else 3073 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3074 3075 // FIXME: handle stuff like: 3076 // void foo() { extern float X(); } 3077 // void bar() { X(); } <-- implicit decl for X in another scope. 3078 3079 // Set a Declarator for the implicit definition: int foo(); 3080 const char *Dummy; 3081 DeclSpec DS; 3082 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3083 Error = Error; // Silence warning. 3084 assert(!Error && "Error setting up implicit decl!"); 3085 Declarator D(DS, Declarator::BlockContext); 3086 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3087 0, 0, 0, Loc, D), 3088 SourceLocation()); 3089 D.SetIdentifier(&II, Loc); 3090 3091 // Insert this function into translation-unit scope. 3092 3093 DeclContext *PrevDC = CurContext; 3094 CurContext = Context.getTranslationUnitDecl(); 3095 3096 FunctionDecl *FD = 3097 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 3098 FD->setImplicit(); 3099 3100 CurContext = PrevDC; 3101 3102 AddKnownFunctionAttributes(FD); 3103 3104 return FD; 3105} 3106 3107/// \brief Adds any function attributes that we know a priori based on 3108/// the declaration of this function. 3109/// 3110/// These attributes can apply both to implicitly-declared builtins 3111/// (like __builtin___printf_chk) or to library-declared functions 3112/// like NSLog or printf. 3113void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3114 if (FD->isInvalidDecl()) 3115 return; 3116 3117 // If this is a built-in function, map its builtin attributes to 3118 // actual attributes. 3119 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3120 // Handle printf-formatting attributes. 3121 unsigned FormatIdx; 3122 bool HasVAListArg; 3123 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3124 if (!FD->getAttr<FormatAttr>()) 3125 FD->addAttr(new FormatAttr("printf", FormatIdx + 1, FormatIdx + 2)); 3126 } 3127 3128 // Mark const if we don't care about errno and that is the only 3129 // thing preventing the function from being const. This allows 3130 // IRgen to use LLVM intrinsics for such functions. 3131 if (!getLangOptions().MathErrno && 3132 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3133 if (!FD->getAttr<ConstAttr>()) 3134 FD->addAttr(new ConstAttr()); 3135 } 3136 } 3137 3138 IdentifierInfo *Name = FD->getIdentifier(); 3139 if (!Name) 3140 return; 3141 if ((!getLangOptions().CPlusPlus && 3142 FD->getDeclContext()->isTranslationUnit()) || 3143 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3144 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3145 LinkageSpecDecl::lang_c)) { 3146 // Okay: this could be a libc/libm/Objective-C function we know 3147 // about. 3148 } else 3149 return; 3150 3151 unsigned KnownID; 3152 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3153 if (KnownFunctionIDs[KnownID] == Name) 3154 break; 3155 3156 switch (KnownID) { 3157 case id_NSLog: 3158 case id_NSLogv: 3159 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3160 // FIXME: We known better than our headers. 3161 const_cast<FormatAttr *>(Format)->setType("printf"); 3162 } else 3163 FD->addAttr(new FormatAttr("printf", 1, 2)); 3164 break; 3165 3166 case id_asprintf: 3167 case id_vasprintf: 3168 if (!FD->getAttr<FormatAttr>()) 3169 FD->addAttr(new FormatAttr("printf", 2, 3)); 3170 break; 3171 3172 default: 3173 // Unknown function or known function without any attributes to 3174 // add. Do nothing. 3175 break; 3176 } 3177} 3178 3179TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 3180 Decl *LastDeclarator) { 3181 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3182 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3183 3184 // Scope manipulation handled by caller. 3185 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3186 D.getIdentifierLoc(), 3187 D.getIdentifier(), 3188 T); 3189 NewTD->setNextDeclarator(LastDeclarator); 3190 if (D.getInvalidType()) 3191 NewTD->setInvalidDecl(); 3192 return NewTD; 3193} 3194 3195/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3196/// former case, Name will be non-null. In the later case, Name will be null. 3197/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3198/// reference/declaration/definition of a tag. 3199Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3200 SourceLocation KWLoc, const CXXScopeSpec &SS, 3201 IdentifierInfo *Name, SourceLocation NameLoc, 3202 AttributeList *Attr) { 3203 // If this is not a definition, it must have a name. 3204 assert((Name != 0 || TK == TK_Definition) && 3205 "Nameless record must be a definition!"); 3206 3207 TagDecl::TagKind Kind; 3208 switch (TagSpec) { 3209 default: assert(0 && "Unknown tag type!"); 3210 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3211 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3212 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3213 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3214 } 3215 3216 DeclContext *SearchDC = CurContext; 3217 DeclContext *DC = CurContext; 3218 NamedDecl *PrevDecl = 0; 3219 3220 bool Invalid = false; 3221 3222 if (Name && SS.isNotEmpty()) { 3223 // We have a nested-name tag ('struct foo::bar'). 3224 3225 // Check for invalid 'foo::'. 3226 if (SS.isInvalid()) { 3227 Name = 0; 3228 goto CreateNewDecl; 3229 } 3230 3231 DC = static_cast<DeclContext*>(SS.getScopeRep()); 3232 SearchDC = DC; 3233 // Look-up name inside 'foo::'. 3234 PrevDecl = dyn_cast_or_null<TagDecl>( 3235 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3236 3237 // A tag 'foo::bar' must already exist. 3238 if (PrevDecl == 0) { 3239 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3240 Name = 0; 3241 goto CreateNewDecl; 3242 } 3243 } else if (Name) { 3244 // If this is a named struct, check to see if there was a previous forward 3245 // declaration or definition. 3246 // FIXME: We're looking into outer scopes here, even when we 3247 // shouldn't be. Doing so can result in ambiguities that we 3248 // shouldn't be diagnosing. 3249 LookupResult R = LookupName(S, Name, LookupTagName, 3250 /*RedeclarationOnly=*/(TK != TK_Reference)); 3251 if (R.isAmbiguous()) { 3252 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3253 // FIXME: This is not best way to recover from case like: 3254 // 3255 // struct S s; 3256 // 3257 // causes needless err_ovl_no_viable_function_in_init latter. 3258 Name = 0; 3259 PrevDecl = 0; 3260 Invalid = true; 3261 } 3262 else 3263 PrevDecl = R; 3264 3265 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3266 // FIXME: This makes sure that we ignore the contexts associated 3267 // with C structs, unions, and enums when looking for a matching 3268 // tag declaration or definition. See the similar lookup tweak 3269 // in Sema::LookupName; is there a better way to deal with this? 3270 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3271 SearchDC = SearchDC->getParent(); 3272 } 3273 } 3274 3275 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3276 // Maybe we will complain about the shadowed template parameter. 3277 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3278 // Just pretend that we didn't see the previous declaration. 3279 PrevDecl = 0; 3280 } 3281 3282 if (PrevDecl) { 3283 // Check whether the previous declaration is usable. 3284 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3285 3286 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3287 // If this is a use of a previous tag, or if the tag is already declared 3288 // in the same scope (so that the definition/declaration completes or 3289 // rementions the tag), reuse the decl. 3290 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3291 // Make sure that this wasn't declared as an enum and now used as a 3292 // struct or something similar. 3293 if (PrevTagDecl->getTagKind() != Kind) { 3294 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3295 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3296 // Recover by making this an anonymous redefinition. 3297 Name = 0; 3298 PrevDecl = 0; 3299 Invalid = true; 3300 } else { 3301 // If this is a use, just return the declaration we found. 3302 3303 // FIXME: In the future, return a variant or some other clue 3304 // for the consumer of this Decl to know it doesn't own it. 3305 // For our current ASTs this shouldn't be a problem, but will 3306 // need to be changed with DeclGroups. 3307 if (TK == TK_Reference) 3308 return PrevDecl; 3309 3310 // Diagnose attempts to redefine a tag. 3311 if (TK == TK_Definition) { 3312 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3313 Diag(NameLoc, diag::err_redefinition) << Name; 3314 Diag(Def->getLocation(), diag::note_previous_definition); 3315 // If this is a redefinition, recover by making this 3316 // struct be anonymous, which will make any later 3317 // references get the previous definition. 3318 Name = 0; 3319 PrevDecl = 0; 3320 Invalid = true; 3321 } else { 3322 // If the type is currently being defined, complain 3323 // about a nested redefinition. 3324 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3325 if (Tag->isBeingDefined()) { 3326 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3327 Diag(PrevTagDecl->getLocation(), 3328 diag::note_previous_definition); 3329 Name = 0; 3330 PrevDecl = 0; 3331 Invalid = true; 3332 } 3333 } 3334 3335 // Okay, this is definition of a previously declared or referenced 3336 // tag PrevDecl. We're going to create a new Decl for it. 3337 } 3338 } 3339 // If we get here we have (another) forward declaration or we 3340 // have a definition. Just create a new decl. 3341 } else { 3342 // If we get here, this is a definition of a new tag type in a nested 3343 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3344 // new decl/type. We set PrevDecl to NULL so that the entities 3345 // have distinct types. 3346 PrevDecl = 0; 3347 } 3348 // If we get here, we're going to create a new Decl. If PrevDecl 3349 // is non-NULL, it's a definition of the tag declared by 3350 // PrevDecl. If it's NULL, we have a new definition. 3351 } else { 3352 // PrevDecl is a namespace, template, or anything else 3353 // that lives in the IDNS_Tag identifier namespace. 3354 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3355 // The tag name clashes with a namespace name, issue an error and 3356 // recover by making this tag be anonymous. 3357 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3358 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3359 Name = 0; 3360 PrevDecl = 0; 3361 Invalid = true; 3362 } else { 3363 // The existing declaration isn't relevant to us; we're in a 3364 // new scope, so clear out the previous declaration. 3365 PrevDecl = 0; 3366 } 3367 } 3368 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3369 (Kind != TagDecl::TK_enum)) { 3370 // C++ [basic.scope.pdecl]p5: 3371 // -- for an elaborated-type-specifier of the form 3372 // 3373 // class-key identifier 3374 // 3375 // if the elaborated-type-specifier is used in the 3376 // decl-specifier-seq or parameter-declaration-clause of a 3377 // function defined in namespace scope, the identifier is 3378 // declared as a class-name in the namespace that contains 3379 // the declaration; otherwise, except as a friend 3380 // declaration, the identifier is declared in the smallest 3381 // non-class, non-function-prototype scope that contains the 3382 // declaration. 3383 // 3384 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3385 // C structs and unions. 3386 3387 // Find the context where we'll be declaring the tag. 3388 // FIXME: We would like to maintain the current DeclContext as the 3389 // lexical context, 3390 while (SearchDC->isRecord()) 3391 SearchDC = SearchDC->getParent(); 3392 3393 // Find the scope where we'll be declaring the tag. 3394 while (S->isClassScope() || 3395 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3396 ((S->getFlags() & Scope::DeclScope) == 0) || 3397 (S->getEntity() && 3398 ((DeclContext *)S->getEntity())->isTransparentContext())) 3399 S = S->getParent(); 3400 } 3401 3402CreateNewDecl: 3403 3404 // If there is an identifier, use the location of the identifier as the 3405 // location of the decl, otherwise use the location of the struct/union 3406 // keyword. 3407 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3408 3409 // Otherwise, create a new declaration. If there is a previous 3410 // declaration of the same entity, the two will be linked via 3411 // PrevDecl. 3412 TagDecl *New; 3413 3414 if (Kind == TagDecl::TK_enum) { 3415 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3416 // enum X { A, B, C } D; D should chain to X. 3417 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3418 cast_or_null<EnumDecl>(PrevDecl)); 3419 // If this is an undefined enum, warn. 3420 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3421 } else { 3422 // struct/union/class 3423 3424 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3425 // struct X { int A; } D; D should chain to X. 3426 if (getLangOptions().CPlusPlus) 3427 // FIXME: Look for a way to use RecordDecl for simple structs. 3428 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3429 cast_or_null<CXXRecordDecl>(PrevDecl)); 3430 else 3431 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3432 cast_or_null<RecordDecl>(PrevDecl)); 3433 } 3434 3435 if (Kind != TagDecl::TK_enum) { 3436 // Handle #pragma pack: if the #pragma pack stack has non-default 3437 // alignment, make up a packed attribute for this decl. These 3438 // attributes are checked when the ASTContext lays out the 3439 // structure. 3440 // 3441 // It is important for implementing the correct semantics that this 3442 // happen here (in act on tag decl). The #pragma pack stack is 3443 // maintained as a result of parser callbacks which can occur at 3444 // many points during the parsing of a struct declaration (because 3445 // the #pragma tokens are effectively skipped over during the 3446 // parsing of the struct). 3447 if (unsigned Alignment = getPragmaPackAlignment()) 3448 New->addAttr(new PackedAttr(Alignment * 8)); 3449 } 3450 3451 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3452 // C++ [dcl.typedef]p3: 3453 // [...] Similarly, in a given scope, a class or enumeration 3454 // shall not be declared with the same name as a typedef-name 3455 // that is declared in that scope and refers to a type other 3456 // than the class or enumeration itself. 3457 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3458 TypedefDecl *PrevTypedef = 0; 3459 if (Lookup.getKind() == LookupResult::Found) 3460 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3461 3462 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3463 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3464 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3465 Diag(Loc, diag::err_tag_definition_of_typedef) 3466 << Context.getTypeDeclType(New) 3467 << PrevTypedef->getUnderlyingType(); 3468 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3469 Invalid = true; 3470 } 3471 } 3472 3473 if (Invalid) 3474 New->setInvalidDecl(); 3475 3476 if (Attr) 3477 ProcessDeclAttributeList(New, Attr); 3478 3479 // If we're declaring or defining a tag in function prototype scope 3480 // in C, note that this type can only be used within the function. 3481 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3482 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3483 3484 // Set the lexical context. If the tag has a C++ scope specifier, the 3485 // lexical context will be different from the semantic context. 3486 New->setLexicalDeclContext(CurContext); 3487 3488 if (TK == TK_Definition) 3489 New->startDefinition(); 3490 3491 // If this has an identifier, add it to the scope stack. 3492 if (Name) { 3493 S = getNonFieldDeclScope(S); 3494 PushOnScopeChains(New, S); 3495 } else { 3496 CurContext->addDecl(New); 3497 } 3498 3499 return New; 3500} 3501 3502void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3503 AdjustDeclIfTemplate(TagD); 3504 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3505 3506 // Enter the tag context. 3507 PushDeclContext(S, Tag); 3508 3509 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3510 FieldCollector->StartClass(); 3511 3512 if (Record->getIdentifier()) { 3513 // C++ [class]p2: 3514 // [...] The class-name is also inserted into the scope of the 3515 // class itself; this is known as the injected-class-name. For 3516 // purposes of access checking, the injected-class-name is treated 3517 // as if it were a public member name. 3518 RecordDecl *InjectedClassName 3519 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3520 CurContext, Record->getLocation(), 3521 Record->getIdentifier(), Record); 3522 InjectedClassName->setImplicit(); 3523 PushOnScopeChains(InjectedClassName, S); 3524 } 3525 } 3526} 3527 3528void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3529 AdjustDeclIfTemplate(TagD); 3530 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3531 3532 if (isa<CXXRecordDecl>(Tag)) 3533 FieldCollector->FinishClass(); 3534 3535 // Exit this scope of this tag's definition. 3536 PopDeclContext(); 3537 3538 // Notify the consumer that we've defined a tag. 3539 Consumer.HandleTagDeclDefinition(Tag); 3540} 3541 3542bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3543 QualType FieldTy, const Expr *BitWidth) { 3544 // FIXME: 6.7.2.1p4 - verify the field type. 3545 3546 llvm::APSInt Value; 3547 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3548 return true; 3549 3550 // Zero-width bitfield is ok for anonymous field. 3551 if (Value == 0 && FieldName) 3552 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3553 3554 if (Value.isNegative()) 3555 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3556 3557 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3558 // FIXME: We won't need the 0 size once we check that the field type is valid. 3559 if (TypeSize && Value.getZExtValue() > TypeSize) 3560 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3561 << FieldName << (unsigned)TypeSize; 3562 3563 return false; 3564} 3565 3566/// ActOnField - Each field of a struct/union/class is passed into this in order 3567/// to create a FieldDecl object for it. 3568Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3569 SourceLocation DeclStart, 3570 Declarator &D, ExprTy *BitfieldWidth) { 3571 IdentifierInfo *II = D.getIdentifier(); 3572 Expr *BitWidth = (Expr*)BitfieldWidth; 3573 SourceLocation Loc = DeclStart; 3574 RecordDecl *Record = (RecordDecl *)TagD; 3575 if (II) Loc = D.getIdentifierLoc(); 3576 3577 // FIXME: Unnamed fields can be handled in various different ways, for 3578 // example, unnamed unions inject all members into the struct namespace! 3579 3580 QualType T = GetTypeForDeclarator(D, S); 3581 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3582 bool InvalidDecl = false; 3583 3584 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3585 // than a variably modified type. 3586 if (T->isVariablyModifiedType()) { 3587 bool SizeIsNegative; 3588 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3589 SizeIsNegative); 3590 if (!FixedTy.isNull()) { 3591 Diag(Loc, diag::warn_illegal_constant_array_size); 3592 T = FixedTy; 3593 } else { 3594 if (SizeIsNegative) 3595 Diag(Loc, diag::err_typecheck_negative_array_size); 3596 else 3597 Diag(Loc, diag::err_typecheck_field_variable_size); 3598 T = Context.IntTy; 3599 InvalidDecl = true; 3600 } 3601 } 3602 3603 if (BitWidth) { 3604 if (VerifyBitField(Loc, II, T, BitWidth)) 3605 InvalidDecl = true; 3606 } else { 3607 // Not a bitfield. 3608 3609 // validate II. 3610 3611 } 3612 3613 FieldDecl *NewFD = FieldDecl::Create(Context, Record, 3614 Loc, II, T, BitWidth, 3615 D.getDeclSpec().getStorageClassSpec() == 3616 DeclSpec::SCS_mutable); 3617 3618 if (II) { 3619 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3620 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3621 && !isa<TagDecl>(PrevDecl)) { 3622 Diag(Loc, diag::err_duplicate_member) << II; 3623 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3624 NewFD->setInvalidDecl(); 3625 Record->setInvalidDecl(); 3626 } 3627 } 3628 3629 if (getLangOptions().CPlusPlus) { 3630 CheckExtraCXXDefaultArguments(D); 3631 if (!T->isPODType()) 3632 cast<CXXRecordDecl>(Record)->setPOD(false); 3633 } 3634 3635 ProcessDeclAttributes(NewFD, D); 3636 if (T.isObjCGCWeak()) 3637 Diag(Loc, diag::warn_attribute_weak_on_field); 3638 3639 if (D.getInvalidType() || InvalidDecl) 3640 NewFD->setInvalidDecl(); 3641 3642 if (II) { 3643 PushOnScopeChains(NewFD, S); 3644 } else 3645 Record->addDecl(NewFD); 3646 3647 return NewFD; 3648} 3649 3650/// TranslateIvarVisibility - Translate visibility from a token ID to an 3651/// AST enum value. 3652static ObjCIvarDecl::AccessControl 3653TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3654 switch (ivarVisibility) { 3655 default: assert(0 && "Unknown visitibility kind"); 3656 case tok::objc_private: return ObjCIvarDecl::Private; 3657 case tok::objc_public: return ObjCIvarDecl::Public; 3658 case tok::objc_protected: return ObjCIvarDecl::Protected; 3659 case tok::objc_package: return ObjCIvarDecl::Package; 3660 } 3661} 3662 3663/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3664/// in order to create an IvarDecl object for it. 3665Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3666 SourceLocation DeclStart, 3667 Declarator &D, ExprTy *BitfieldWidth, 3668 tok::ObjCKeywordKind Visibility) { 3669 3670 IdentifierInfo *II = D.getIdentifier(); 3671 Expr *BitWidth = (Expr*)BitfieldWidth; 3672 SourceLocation Loc = DeclStart; 3673 if (II) Loc = D.getIdentifierLoc(); 3674 3675 // FIXME: Unnamed fields can be handled in various different ways, for 3676 // example, unnamed unions inject all members into the struct namespace! 3677 3678 QualType T = GetTypeForDeclarator(D, S); 3679 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3680 bool InvalidDecl = false; 3681 3682 if (BitWidth) { 3683 // 6.7.2.1p3, 6.7.2.1p4 3684 if (VerifyBitField(Loc, II, T, BitWidth)) 3685 InvalidDecl = true; 3686 } else { 3687 // Not a bitfield. 3688 3689 // validate II. 3690 3691 } 3692 3693 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3694 // than a variably modified type. 3695 if (T->isVariablyModifiedType()) { 3696 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3697 InvalidDecl = true; 3698 } 3699 3700 // Get the visibility (access control) for this ivar. 3701 ObjCIvarDecl::AccessControl ac = 3702 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3703 : ObjCIvarDecl::None; 3704 3705 // Construct the decl. 3706 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3707 (Expr *)BitfieldWidth); 3708 3709 if (II) { 3710 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3711 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3712 && !isa<TagDecl>(PrevDecl)) { 3713 Diag(Loc, diag::err_duplicate_member) << II; 3714 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3715 NewID->setInvalidDecl(); 3716 } 3717 } 3718 3719 // Process attributes attached to the ivar. 3720 ProcessDeclAttributes(NewID, D); 3721 3722 if (D.getInvalidType() || InvalidDecl) 3723 NewID->setInvalidDecl(); 3724 3725 if (II) { 3726 // FIXME: When interfaces are DeclContexts, we'll need to add 3727 // these to the interface. 3728 S->AddDecl(NewID); 3729 IdResolver.AddDecl(NewID); 3730 } 3731 3732 return NewID; 3733} 3734 3735void Sema::ActOnFields(Scope* S, 3736 SourceLocation RecLoc, DeclTy *RecDecl, 3737 DeclTy **Fields, unsigned NumFields, 3738 SourceLocation LBrac, SourceLocation RBrac, 3739 AttributeList *Attr) { 3740 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3741 assert(EnclosingDecl && "missing record or interface decl"); 3742 3743 // If the decl this is being inserted into is invalid, then it may be a 3744 // redeclaration or some other bogus case. Don't try to add fields to it. 3745 if (EnclosingDecl->isInvalidDecl()) { 3746 // FIXME: Deallocate fields? 3747 return; 3748 } 3749 3750 3751 // Verify that all the fields are okay. 3752 unsigned NumNamedMembers = 0; 3753 llvm::SmallVector<FieldDecl*, 32> RecFields; 3754 3755 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3756 for (unsigned i = 0; i != NumFields; ++i) { 3757 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3758 assert(FD && "missing field decl"); 3759 3760 // Get the type for the field. 3761 Type *FDTy = FD->getType().getTypePtr(); 3762 3763 if (!FD->isAnonymousStructOrUnion()) { 3764 // Remember all fields written by the user. 3765 RecFields.push_back(FD); 3766 } 3767 3768 // C99 6.7.2.1p2 - A field may not be a function type. 3769 if (FDTy->isFunctionType()) { 3770 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3771 << FD->getDeclName(); 3772 FD->setInvalidDecl(); 3773 EnclosingDecl->setInvalidDecl(); 3774 continue; 3775 } 3776 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3777 if (FDTy->isIncompleteType()) { 3778 if (!Record) { // Incomplete ivar type is always an error. 3779 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3780 diag::err_field_incomplete); 3781 FD->setInvalidDecl(); 3782 EnclosingDecl->setInvalidDecl(); 3783 continue; 3784 } 3785 if (i != NumFields-1 || // ... that the last member ... 3786 !Record->isStruct() || // ... of a structure ... 3787 !FDTy->isArrayType()) { //... may have incomplete array type. 3788 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3789 diag::err_field_incomplete); 3790 FD->setInvalidDecl(); 3791 EnclosingDecl->setInvalidDecl(); 3792 continue; 3793 } 3794 if (NumNamedMembers < 1) { //... must have more than named member ... 3795 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3796 << FD->getDeclName(); 3797 FD->setInvalidDecl(); 3798 EnclosingDecl->setInvalidDecl(); 3799 continue; 3800 } 3801 // Okay, we have a legal flexible array member at the end of the struct. 3802 if (Record) 3803 Record->setHasFlexibleArrayMember(true); 3804 } 3805 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3806 /// field of another structure or the element of an array. 3807 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3808 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3809 // If this is a member of a union, then entire union becomes "flexible". 3810 if (Record && Record->isUnion()) { 3811 Record->setHasFlexibleArrayMember(true); 3812 } else { 3813 // If this is a struct/class and this is not the last element, reject 3814 // it. Note that GCC supports variable sized arrays in the middle of 3815 // structures. 3816 if (i != NumFields-1) { 3817 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3818 << FD->getDeclName(); 3819 FD->setInvalidDecl(); 3820 EnclosingDecl->setInvalidDecl(); 3821 continue; 3822 } 3823 // We support flexible arrays at the end of structs in other structs 3824 // as an extension. 3825 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3826 << FD->getDeclName(); 3827 if (Record) 3828 Record->setHasFlexibleArrayMember(true); 3829 } 3830 } 3831 } 3832 /// A field cannot be an Objective-c object 3833 if (FDTy->isObjCInterfaceType()) { 3834 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3835 FD->setInvalidDecl(); 3836 EnclosingDecl->setInvalidDecl(); 3837 continue; 3838 } 3839 // Keep track of the number of named members. 3840 if (FD->getIdentifier()) 3841 ++NumNamedMembers; 3842 } 3843 3844 // Okay, we successfully defined 'Record'. 3845 if (Record) { 3846 Record->completeDefinition(Context); 3847 } else { 3848 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3849 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3850 ID->setIVarList(ClsFields, RecFields.size(), Context); 3851 ID->setLocEnd(RBrac); 3852 3853 // Must enforce the rule that ivars in the base classes may not be 3854 // duplicates. 3855 if (ID->getSuperClass()) { 3856 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3857 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3858 ObjCIvarDecl* Ivar = (*IVI); 3859 IdentifierInfo *II = Ivar->getIdentifier(); 3860 ObjCIvarDecl* prevIvar = ID->getSuperClass()->lookupInstanceVariable(II); 3861 if (prevIvar) { 3862 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3863 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3864 } 3865 } 3866 } 3867 } else if (ObjCImplementationDecl *IMPDecl = 3868 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3869 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3870 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3871 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3872 } 3873 } 3874 3875 if (Attr) 3876 ProcessDeclAttributeList(Record, Attr); 3877} 3878 3879Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3880 DeclTy *lastEnumConst, 3881 SourceLocation IdLoc, IdentifierInfo *Id, 3882 SourceLocation EqualLoc, ExprTy *val) { 3883 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3884 EnumConstantDecl *LastEnumConst = 3885 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3886 Expr *Val = static_cast<Expr*>(val); 3887 3888 // The scope passed in may not be a decl scope. Zip up the scope tree until 3889 // we find one that is. 3890 S = getNonFieldDeclScope(S); 3891 3892 // Verify that there isn't already something declared with this name in this 3893 // scope. 3894 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3895 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3896 // Maybe we will complain about the shadowed template parameter. 3897 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3898 // Just pretend that we didn't see the previous declaration. 3899 PrevDecl = 0; 3900 } 3901 3902 if (PrevDecl) { 3903 // When in C++, we may get a TagDecl with the same name; in this case the 3904 // enum constant will 'hide' the tag. 3905 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3906 "Received TagDecl when not in C++!"); 3907 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3908 if (isa<EnumConstantDecl>(PrevDecl)) 3909 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3910 else 3911 Diag(IdLoc, diag::err_redefinition) << Id; 3912 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3913 Val->Destroy(Context); 3914 return 0; 3915 } 3916 } 3917 3918 llvm::APSInt EnumVal(32); 3919 QualType EltTy; 3920 if (Val) { 3921 // Make sure to promote the operand type to int. 3922 UsualUnaryConversions(Val); 3923 3924 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3925 SourceLocation ExpLoc; 3926 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3927 Val->Destroy(Context); 3928 Val = 0; // Just forget about it. 3929 } else { 3930 EltTy = Val->getType(); 3931 } 3932 } 3933 3934 if (!Val) { 3935 if (LastEnumConst) { 3936 // Assign the last value + 1. 3937 EnumVal = LastEnumConst->getInitVal(); 3938 ++EnumVal; 3939 3940 // Check for overflow on increment. 3941 if (EnumVal < LastEnumConst->getInitVal()) 3942 Diag(IdLoc, diag::warn_enum_value_overflow); 3943 3944 EltTy = LastEnumConst->getType(); 3945 } else { 3946 // First value, set to zero. 3947 EltTy = Context.IntTy; 3948 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3949 } 3950 } 3951 3952 EnumConstantDecl *New = 3953 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3954 Val, EnumVal); 3955 3956 // Register this decl in the current scope stack. 3957 PushOnScopeChains(New, S); 3958 3959 return New; 3960} 3961 3962// FIXME: For consistency with ActOnFields(), we should have the parser 3963// pass in the source location for the left/right braces. 3964void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3965 DeclTy **Elements, unsigned NumElements) { 3966 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3967 QualType EnumType = Context.getTypeDeclType(Enum); 3968 3969 // TODO: If the result value doesn't fit in an int, it must be a long or long 3970 // long value. ISO C does not support this, but GCC does as an extension, 3971 // emit a warning. 3972 unsigned IntWidth = Context.Target.getIntWidth(); 3973 3974 // Verify that all the values are okay, compute the size of the values, and 3975 // reverse the list. 3976 unsigned NumNegativeBits = 0; 3977 unsigned NumPositiveBits = 0; 3978 3979 // Keep track of whether all elements have type int. 3980 bool AllElementsInt = true; 3981 3982 for (unsigned i = 0; i != NumElements; ++i) { 3983 EnumConstantDecl *ECD = 3984 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3985 if (!ECD) continue; // Already issued a diagnostic. 3986 3987 // If the enum value doesn't fit in an int, emit an extension warning. 3988 const llvm::APSInt &InitVal = ECD->getInitVal(); 3989 assert(InitVal.getBitWidth() >= IntWidth && 3990 "Should have promoted value to int"); 3991 if (InitVal.getBitWidth() > IntWidth) { 3992 llvm::APSInt V(InitVal); 3993 V.trunc(IntWidth); 3994 V.extend(InitVal.getBitWidth()); 3995 if (V != InitVal) 3996 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3997 << InitVal.toString(10); 3998 } 3999 4000 // Keep track of the size of positive and negative values. 4001 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4002 NumPositiveBits = std::max(NumPositiveBits, 4003 (unsigned)InitVal.getActiveBits()); 4004 else 4005 NumNegativeBits = std::max(NumNegativeBits, 4006 (unsigned)InitVal.getMinSignedBits()); 4007 4008 // Keep track of whether every enum element has type int (very commmon). 4009 if (AllElementsInt) 4010 AllElementsInt = ECD->getType() == Context.IntTy; 4011 } 4012 4013 // Figure out the type that should be used for this enum. 4014 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4015 QualType BestType; 4016 unsigned BestWidth; 4017 4018 if (NumNegativeBits) { 4019 // If there is a negative value, figure out the smallest integer type (of 4020 // int/long/longlong) that fits. 4021 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4022 BestType = Context.IntTy; 4023 BestWidth = IntWidth; 4024 } else { 4025 BestWidth = Context.Target.getLongWidth(); 4026 4027 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4028 BestType = Context.LongTy; 4029 else { 4030 BestWidth = Context.Target.getLongLongWidth(); 4031 4032 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4033 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4034 BestType = Context.LongLongTy; 4035 } 4036 } 4037 } else { 4038 // If there is no negative value, figure out which of uint, ulong, ulonglong 4039 // fits. 4040 if (NumPositiveBits <= IntWidth) { 4041 BestType = Context.UnsignedIntTy; 4042 BestWidth = IntWidth; 4043 } else if (NumPositiveBits <= 4044 (BestWidth = Context.Target.getLongWidth())) { 4045 BestType = Context.UnsignedLongTy; 4046 } else { 4047 BestWidth = Context.Target.getLongLongWidth(); 4048 assert(NumPositiveBits <= BestWidth && 4049 "How could an initializer get larger than ULL?"); 4050 BestType = Context.UnsignedLongLongTy; 4051 } 4052 } 4053 4054 // Loop over all of the enumerator constants, changing their types to match 4055 // the type of the enum if needed. 4056 for (unsigned i = 0; i != NumElements; ++i) { 4057 EnumConstantDecl *ECD = 4058 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 4059 if (!ECD) continue; // Already issued a diagnostic. 4060 4061 // Standard C says the enumerators have int type, but we allow, as an 4062 // extension, the enumerators to be larger than int size. If each 4063 // enumerator value fits in an int, type it as an int, otherwise type it the 4064 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4065 // that X has type 'int', not 'unsigned'. 4066 if (ECD->getType() == Context.IntTy) { 4067 // Make sure the init value is signed. 4068 llvm::APSInt IV = ECD->getInitVal(); 4069 IV.setIsSigned(true); 4070 ECD->setInitVal(IV); 4071 4072 if (getLangOptions().CPlusPlus) 4073 // C++ [dcl.enum]p4: Following the closing brace of an 4074 // enum-specifier, each enumerator has the type of its 4075 // enumeration. 4076 ECD->setType(EnumType); 4077 continue; // Already int type. 4078 } 4079 4080 // Determine whether the value fits into an int. 4081 llvm::APSInt InitVal = ECD->getInitVal(); 4082 bool FitsInInt; 4083 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4084 FitsInInt = InitVal.getActiveBits() < IntWidth; 4085 else 4086 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4087 4088 // If it fits into an integer type, force it. Otherwise force it to match 4089 // the enum decl type. 4090 QualType NewTy; 4091 unsigned NewWidth; 4092 bool NewSign; 4093 if (FitsInInt) { 4094 NewTy = Context.IntTy; 4095 NewWidth = IntWidth; 4096 NewSign = true; 4097 } else if (ECD->getType() == BestType) { 4098 // Already the right type! 4099 if (getLangOptions().CPlusPlus) 4100 // C++ [dcl.enum]p4: Following the closing brace of an 4101 // enum-specifier, each enumerator has the type of its 4102 // enumeration. 4103 ECD->setType(EnumType); 4104 continue; 4105 } else { 4106 NewTy = BestType; 4107 NewWidth = BestWidth; 4108 NewSign = BestType->isSignedIntegerType(); 4109 } 4110 4111 // Adjust the APSInt value. 4112 InitVal.extOrTrunc(NewWidth); 4113 InitVal.setIsSigned(NewSign); 4114 ECD->setInitVal(InitVal); 4115 4116 // Adjust the Expr initializer and type. 4117 if (ECD->getInitExpr()) 4118 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4119 /*isLvalue=*/false)); 4120 if (getLangOptions().CPlusPlus) 4121 // C++ [dcl.enum]p4: Following the closing brace of an 4122 // enum-specifier, each enumerator has the type of its 4123 // enumeration. 4124 ECD->setType(EnumType); 4125 else 4126 ECD->setType(NewTy); 4127 } 4128 4129 Enum->completeDefinition(Context, BestType); 4130} 4131 4132Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4133 ExprArg expr) { 4134 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4135 4136 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 4137} 4138 4139